Difference between revisions of "Big Digit Driver Assembly Instructions"

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|Type
 
|Type
 
|Vendor
 
|Vendor
|Vendor Part Number
+
|Part Number
|Quantity per Board
+
|Quantity/Board
 
|----
 
|----
 
|1
 
|1
 
|N/A
 
|N/A
|PCB
+
|Printed circuit board
 
|Big Digit Driver board
 
|Big Digit Driver board
|EMS
+
|Evil Mad Scientist LLC
 
|N/A
 
|N/A
 
|1
 
|1
Line 22: Line 22:
 
|2
 
|2
 
|R25
 
|R25
|Current Sense Resistor for DP
+
|24 ohm resistor
|22 ohm, substituting 24 ohm 1/4 watt carbon film resistor
+
|Carbon film resistor, 1/4 watt
 
|Digikey
 
|Digikey
 
|24QBK-ND
 
|24QBK-ND
Line 29: Line 29:
 
|----
 
|----
 
|3
 
|3
|R1 through R5
+
|R1 - R5
|DP Load Resistors
+
|68 ohm resistor
|68 ohm 1/4 watt carbon film resistors
+
|Carbon film resistor, 1/4 watt
 
|DigiKey
 
|DigiKey
 
|68QBK-ND
 
|68QBK-ND
Line 38: Line 38:
 
|4
 
|4
 
|R11,R13,R15,R17,R19,R21,R23
 
|R11,R13,R15,R17,R19,R21,R23
|Current Sense Resistors
+
|16 ohm resistor
|16 ohm 1/4 watt carbon film resistors
+
|Carbon film resistor, 1/4 watt
 
|Digikey
 
|Digikey
 
|16QBK-ND
 
|16QBK-ND
Line 46: Line 46:
 
|5
 
|5
 
|R12,R14,R16,R18,R20,R22,R24,R26,R27
 
|R12,R14,R16,R18,R20,R22,R24,R26,R27
|Base Resistors, Power LED Resistor
+
|1 k resistor
|1k ohm 1/4 watt carbon film resistors
+
|Carbon film resistor, 1/4 watt
 
|Digikey
 
|Digikey
 
|1.0KQBK-ND
 
|1.0KQBK-ND
Line 54: Line 54:
 
|6
 
|6
 
|D1, D2
 
|D1, D2
|Linear Regulator Load, DP Load (Diodes)
+
|10 V, 1 W zener diode
|1N4740A, 10V, 1 watt
+
|1N4740A
 
|Digikey
 
|Digikey
 
|1N4740A-ND
 
|1N4740A-ND
Line 62: Line 62:
 
|7
 
|7
 
|U9
 
|U9
|Shift Register Socket
+
|IC Socket for shift register
|16 pin 0.3" Socket
+
|16 pin DIP, 0.3" spacing
 
|Digikey
 
|Digikey
 
|A100206-ND
 
|A100206-ND
Line 70: Line 70:
 
|8
 
|8
 
|U10
 
|U10
|Schmitt Trigger Socket
+
|IC Socket for buffer IC
|14 pin 0.3" Socket
+
|14 pin DIP, 0.3" spacing
 
|Digikey
 
|Digikey
 
|3M5462-ND
 
|3M5462-ND
 
|1
 
|1
 
|----
 
|----
|9
+
|rowspan="2"|9
|JP1 thru JP5
+
|JP1 - JP3: DO NOT POPULATE
|Data Out Schmitt Trigger Bypass
+
|Leave Empty!
|Zero ohm 'Resistors'
+
|rowspan="2"|Zero ohm jumpers
|Digikey
+
|rowspan="2"|Digikey
|0.0QTR-ND
+
|rowspan="2"|0.0QTR-ND
|5
+
|rowspan="2"|2
 +
|----
 +
|JP4, JP5
 +
|SPI Ground Jumpers
 
|----
 
|----
 
|10
 
|10
|Q1 thru Q8
+
|Q1 - Q8
|Digital Control Transistors
+
|40V NPN Transistor
|2N3904, NPN Transistor, 40V, TO-92
+
|2N3904, 40V
 
|Digikey
 
|Digikey
 
|2N3904-APCT-ND
 
|2N3904-APCT-ND
Line 94: Line 97:
 
|11
 
|11
 
|U1 thru U8
 
|U1 thru U8
|Current Regulators
+
|Adjustable Linear Regulator
|LM317L, Adjustable Linear Regulator, 0.1A, TO-92
+
|LM317L, 100 mA
 
|Digikey
 
|Digikey
 
|LM317LZ-ND
 
|LM317LZ-ND
Line 102: Line 105:
 
|12
 
|12
 
|U11
 
|U11
|Linear Regulator
+
|5V Linear Regulator
|TL750L05, 5V, 150mA, TO-92
+
|TL750L05, 150 mA
 
|Digikey
 
|Digikey
 
|296-8002-5-ND
 
|296-8002-5-ND
Line 110: Line 113:
 
|13
 
|13
 
|C2
 
|C2
|Bypass Capacitor
+
|Bypass Capacitor, 10 uF
|10uF Ceramic Capacitor
+
|Ceramic Capacitor
 
|Digikey
 
|Digikey
 
|445-4816-ND
 
|445-4816-ND
Line 118: Line 121:
 
|14
 
|14
 
|C1, C3, C4
 
|C1, C3, C4
|Bypass Capacitors
+
|Bypass Capacitors, 0.1 uF
|0.1uF Ceramic Capacitor
+
|Ceramic Capacitor, 25 V
 
|Digikey
 
|Digikey
 
|BC1148TR-ND  
 
|BC1148TR-ND  
Line 126: Line 129:
 
|15
 
|15
 
|LED1
 
|LED1
|Power LED
+
|Indicator LED
|3mm Yellow LED
+
|3mm yellow diffused-lens
 
|Digikey
 
|Digikey
 
|754-1212-ND
 
|754-1212-ND
Line 135: Line 138:
 
|J2, J3
 
|J2, J3
 
|Screw Terminal
 
|Screw Terminal
|2 position euro-style screw terminal
+
|2 position euro-style 3. 5mm
 
|DigiKey
 
|DigiKey
 
|ED2635-ND
 
|ED2635-ND
Line 142: Line 145:
 
|17
 
|17
 
|J5, J6
 
|J5, J6
|SPI Headers
+
|6-pin SPI interface headers
|6 pin (2x3 DIL) 0.1" Header
+
|0.1" DIL Header
 
|Digikey
 
|Digikey
 
|609-3202-ND
 
|609-3202-ND
Line 150: Line 153:
 
|18
 
|18
 
|J4
 
|J4
|Power Jack
+
|Power Jack, high current
|2.1mm ID Barrel Jack
+
|2.1 mm ID Barrel Jack
 
|Digikey
 
|Digikey
 
|CP-002AH-ND
 
|CP-002AH-ND
Line 158: Line 161:
 
|19
 
|19
 
|U9
 
|U9
|Shift Register
+
|Shift Register IC
|74HCT595, 8-bit 16DIP
+
|74HCT595, DIP-16
 
|Digikey
 
|Digikey
 
|568-1560-5-ND
 
|568-1560-5-ND
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|20
 
|20
 
|U10
 
|U10
|Schmitt Trigger
+
|Schmitt-input "buffer" IC
|74ACT14, 16DIP
+
|74ACT14, DIP-16
 
|Digikey
 
|Digikey
 
|296-4368-5-ND
 
|296-4368-5-ND
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|21
 
|21
 
|J1
 
|J1
|Display Connector
+
|Display Connector (card edge)
|11 Position/22 Contact 0.156" pitch board edge connector
+
|11 Position/22 Contact 0.156" pitch
 
|Digikey
 
|Digikey
 
|EBM11DSAN-ND
 
|EBM11DSAN-ND
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|22
 
|22
 
|N/A
 
|N/A
|Display Top Standoffs
+
|Standoffs (for digit top)
|Standoff, 7/8" round
+
|Round, threaded 6-32 x 7/8"
 
|Digikey
 
|Digikey
 
|1848K-ND
 
|1848K-ND
Line 190: Line 193:
 
|23
 
|23
 
|N/A
 
|N/A
|Display Bottom Standoffs
+
|Display/Driver Board Standoffs
|Standoff, round, 3/4"
+
|Round, threaded 6-32 x 3/4"
 
|DigiKey
 
|DigiKey
 
|3488K-ND
 
|3488K-ND
Line 198: Line 201:
 
|24
 
|24
 
|N/A
 
|N/A
|Display Top Standoff Washers
+
|Spacers (for digit top)
|1/16" thick Nylon Washers, #6 screw
+
|#6 x 1/16" nylon washers
|McMaster
+
|McMaster-Carr
 
|90295A090
 
|90295A090
 
|2
 
|2
Line 206: Line 209:
 
|25
 
|25
 
|N/A
 
|N/A
|Display Bottom/Driver Board Standoffs
+
|Display/Driver Board spacer
|1/8" tall Nylon standoff
+
|#6 x 1/8" nylon washer
|McMaster
+
|McMaster-Carr
 
|94639A407
 
|94639A407
 
|2
 
|2
Line 214: Line 217:
 
|26
 
|26
 
|N/A
 
|N/A
|Display Bottom/Driver Board/Mounting Screws
+
|Mounting Screws
|Screw, Button Socket Cap 6-32 x 1/2"
+
|Button Socket Cap Screw, 6-32 x 1/2"
 
|McMaster
 
|McMaster
 
|92949A148
 
|92949A148
|6
+
|8
|----
+
|----  
 
|27
 
|27
 
|N/A
 
|N/A
|Display Top
+
|Delrin Insulator
|Screw, Button socket Cap 6-32 x 3/8"
+
|Delrin Insulator
|McMaster
+
|Evil Mad Scientist LLC
|92949A146
+
|N/A
|2
+
|1
 
|----
 
|----
 
|28
 
|28
 
|N/A
 
|N/A
|Delrin Insulator
+
|Ribbon Cable
|Delrin Insulator
+
|12 inch 6-pin Ribbon cable
|EMS
+
|Evil Mad Scientist LLC
|N/A
+
|562
 
|1
 
|1
 
|----
 
|----
 
|}
 
|}
 
 
  
 
== Assembly procedure ==
 
== Assembly procedure ==
  
Looks a bit imposing, huh? Don't worry, looks can be deceiving. We'll show you where each part goes.
+
This document will show you where each part goes.
  
 
This guide assumes that you have had some soldering experience.  If not, or it's been a while, you may also want to look at pages 2 and 5-7 of the [http://wiki.evilmadscience.com/Bulbdial Bulbdial clock] assembly instructions, which go over basic tools and technique.  And, if you really are a beginner, there are plenty of good tutorials on line, like [http://www.instructables.com/id/How-to-solder/ this one].
 
This guide assumes that you have had some soldering experience.  If not, or it's been a while, you may also want to look at pages 2 and 5-7 of the [http://wiki.evilmadscience.com/Bulbdial Bulbdial clock] assembly instructions, which go over basic tools and technique.  And, if you really are a beginner, there are plenty of good tutorials on line, like [http://www.instructables.com/id/How-to-solder/ this one].
Line 248: Line 249:
  
 
=== 1. The circuit board ===
 
=== 1. The circuit board ===
Here's what the bare circuit board looks like:
+
Here's what the empty printed circuit board looks like:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_001.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_001.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_002.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_002.jpg
  
Line 268: Line 270:
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_004.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_004.jpg
  
This will go in location R25 - it's right above the power jack footprint on the right-hand side of the board.
+
This will go in location R25 - it's right above the power jack footprint on the right-hand side of the board (location J4).
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_005.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_005.jpg
Line 279: Line 281:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_007.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_007.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_008.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_008.jpg
  
Line 288: Line 291:
  
 
=== 3.  Decimal Point Load Resistors ===
 
=== 3.  Decimal Point Load Resistors ===
Let's finish off the decimal point resistors.
+
Next, we'll be installing 68 ohm resistors (color code: Blue/Gray/Black/Gold) in locations R1 through R5.
 
 
We'll be installing 68 ohm resistors (color code: Blue/Gray/Black/Gold) in locations R1 through R5.
 
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_010.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_010.jpg
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Getting the hang of this? Great!
 
Getting the hang of this? Great!
  
Next, let's install the 16 ohms (color code: Brown/Blue/Black/Gold) current sense resistors. These come as a segment from a large spool. Just pull them straight out and straighten the leads as needed.
+
Next, let's install the 16 ohm (color code: Brown/Blue/Black/Gold) resistors. These come as a segment from a large spool. Just pull them straight out and straighten the leads as needed.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_016.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_016.jpg
  
Installation procedure for these is exactly the same as the resistors above. These will go in locations R11, R13, R15, R17, R19, R21, and R23 (in a big line across the middle of the board).
+
Installation procedure for these is exactly the same as the resistors above. These will go in locations R11, R13, R15, R17, R19, R21, and R23 (in a big line across the middle of the board). Here's what they look like when installed:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_017.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_017.jpg
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=== 5.  Base resistors ===
+
=== 5.  Base Resistors ===
Next, locate all the 1k ohm resistors (color code: Brown/Black/Red/Gold) and install them into locations R12, R14, R16, R18, R20, R22, R24, and R26 (again, in a big line across the middle of the board).
+
Next, locate all the 1k ohm resistors (color code: Brown/Black/Red/Gold).
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_018.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_018.jpg
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_019.jpg
 
  
You may have noticed that we didn't use all the 1k ohm resistors available. Thats okay, we'll use the last one in step 6!
+
Install them into locations R12, R14, R16, R18, R20, R22, R24, and R26 (again, in a line across the middle of the board, right above the resistors we installed in step 4). You may have noticed that we didn't use all the 1k ohm resistors available. Thats okay, we'll use the last one in step 6!
  
  
Line 340: Line 340:
 
Last resistor, we promise!
 
Last resistor, we promise!
  
It's a 1k ohm (Brown/Black/Red/Gold), exactly like the resistors in step five. This resistor goes in location R27, between the large IC footprint near the top-middle of the board.
+
It's a 1k ohm (Brown/Black/Red/Gold), exactly like the resistors in step 5. This resistor goes in location R27, between the large IC footprint near the top-middle of the board.
  
 
This is what your board should look like now:
 
This is what your board should look like now:
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http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_022.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_022.jpg
  
Take a look at the diodes. See how they have black lines wrapped around one end of the glass cylinder?
+
Take a look at the diodes. See how they have a black line wrapped around one end of the glass cylinder?
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_021.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_021.jpg
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=== 8. Optional: Schmitt Trigger Bypass ===
+
=== 8. SPI Header Ground Jumpers ===
Big Digit Drivers can be linked in series via the SPI ports on either side of the board. For long runs of digits (three or more) we've included a footprint for a Schmitt trigger - this IC will 'boost' the signals that run down the series of drivers and helps eliminate synchronization issues due to noise and attenuation.
+
Next, we will install the jumpers that connect the Big Digit Driver to the SPI ground line. For this we'll use zero ohm wire jumpers, which look like resistors with a single black stripe instead of four or more. (If you should need additional jumpers beyond those included with the kit, you can use plain wire as a substitute.)
 
 
If, for whatever reason, you don't want to use the Schmitt trigger you can instead install four jumpers in locations JP1, JP2, and JP3 (look in the upper right-hand side of the board).
 
 
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_025.jpg
 
 
 
For this we'll use zero-ohm 'resistors' - they have no real color code, they look like resistors with a single black stripe instead of five or more. They're not really resistors either (well, they do have a resistance - like all wire - but it is very low!) and each could actually be replaced with a length of wire if you prefer.
 
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_030.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_030.jpg
  
They go in like the resistors and diodes in the steps above.
+
We'll be installing them in locations JP5 (upper left-hand side of the board, just below the diodes) and JP4 (upper right-hand side of the board). Here is what they look like when installed.
  
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_032.jpg
+
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_031.jpg
 
 
(Note that in the photo above, jumper JP4 is also installed. Jumper JP4 is covered in step 9 - in this step we're only discussing the three jumpers above it.)
 
  
DO NOT use both the Schmitt trigger and bypass jumpers at the same time! Using both shouldn't cause any damage, but the behavior of digits down the line will be strange and unpredictable.
+
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_090.jpg
  
There is no harm is using the Schmitt trigger on short runs of digits, so unless you have a specific reason to not use it we recommend install the trigger instead of these jumpers.
 
  
 +
''Please note that locations JP1, JP2, and JP3 are normally left unpopulated.''
  
 +
(Aside: Jumpers at JP1-JP3 can be used to bypass the Schmitt-input "buffer" chip. Even though some of our photos do show these installed, please leave JP1-JP3 empty ''unless you really know what you're doing''.  If for a good reason you do install jumpers in JP1-JP3, you ''must not'' install the Schmitt-input "buffer" IC in location U10, and instead leave that socket empty.)
 +
  
=== 9. Optional: SPI header ground connections ===
 
Since Big Digit Drivers can be wired in series essentially indefinitely, we also include the option of isolating the board from the the ground line on the SPI headers. Isolating the ground lines will only be useful to people who are driving a large number of digits on multiple power supplies, so we recommend that you install these jumpers unless you are completely sure that you need to isolate drivers for some reason.
 
  
Once again we'll be using zero ohm 'resistors' - just like above in step 8. We'll be installing them in locations JP5 (upper left-hand side of the board, just below the diodes) and JP4 (upper right-hand side of the board, below the Schmitt trigger bypass).
+
=== 9. Shift Register and Schmitt-input "Buffer" Sockets  ===
 
+
Next, we will install the sockets for the ICs.
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_031.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_032.jpg
 
 
 
 
 
 
 
=== 10. Shift Register and Schmitt Trigger Sockets  ===
 
We don't recommend soldering chips directly to the board, and the kit include sockets for your convenience.
 
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_024.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_024.jpg
Line 409: Line 394:
 
There are two IC footprint (U9 and U10) and they are slightly different sizes (U9 is 16 pins, and U10 is 14 pins). Make sure you have the right socket for the right footprint! If it doesn't drop in, or if the socket doesn't seem to cover the entire footprint, double check that you have the correct socket.
 
There are two IC footprint (U9 and U10) and they are slightly different sizes (U9 is 16 pins, and U10 is 14 pins). Make sure you have the right socket for the right footprint! If it doesn't drop in, or if the socket doesn't seem to cover the entire footprint, double check that you have the correct socket.
  
Take a look at the board - notice the 'notch'/semicircle on one end of the footprint? This is a polarity marking. Match this mark with the notch in the end of of the socket.
+
Take a look at the board - notice the 'notch'/semicircle on one end of the footprint outline? This is a polarity marking. Match this mark with the notch in the end of of the socket.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_025.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_025.jpg
Line 422: Line 407:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_027.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_027.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_028.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_028.jpg
  
Line 429: Line 415:
  
  
=== 11. Digital Control Transistors ===
+
=== 10. Digital Control Transistors ===
 
These transistors are little black cylinders with one side flattened and have three leads coming out one end. They should come attached to a strip of paper tape, but double check their markings just to be sure. They should have the number '2N3904' on the flattened side of the cylinder.
 
These transistors are little black cylinders with one side flattened and have three leads coming out one end. They should come attached to a strip of paper tape, but double check their markings just to be sure. They should have the number '2N3904' on the flattened side of the cylinder.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_033.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_033.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_034.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_034.jpg
  
We will be installing these into locations Q1, Q2, Q3, Q4, Q5, Q6, Q7, and Q8 (in a line across the middle of the board). Note that orientation matters! Take a peek at the board. See how the footprint is a circle with a flat side? That flat side matches up with the flat side on the part itself (the side with the text on it) - in other words, the flat side of the part should be facing toward the top of the board.
+
We will be installing these into locations Q1, Q2, Q3, Q4, Q5, Q6, Q7, and Q8 (in a line across the middle of the board). Note that orientation matters! Take a look at the board. See how the footprint is a circle with a flat side? That flat side matches up with the flat side on the part itself (the side with the text on it) - in other words, the flat side of the part should be facing toward the top of the board.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_035.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_035.jpg
  
 
You may have noticed that the transistors also come with pre-bent leads - all you need to do is cut them loose from the paper strip and drop them in place.
 
You may have noticed that the transistors also come with pre-bent leads - all you need to do is cut them loose from the paper strip and drop them in place.
 +
 +
 +
 +
=== 11. Current Regulators  ===
 +
These will look similar to the transistors in step 10, except that they will have the number 'LM317' on them, do not come attached to paper tape, and do not have their leads pre-bent.
 +
 +
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_036.jpg
 +
 +
Install these in a line just below the transistors, in locations U1, U2, U3, U4, U5, U6, U7, and U8. Once again, orientation matters! Be sure to line up the flat side of the regulator with the flat side of the footprint on the board (the flat side should be facing toward the top of the board).
 +
 +
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_037.jpg
  
  
  
 
=== 12. Five Volt Linear Regulator ===
 
=== 12. Five Volt Linear Regulator ===
These will look similar to the transistors in step 11, except: they will have the number '750L05' on them, do not come attached to paper tape, and do not have their leads pre-bent.
+
This part will look look identical to the current regulators in step 11, except that they will have the number '750L05' on them.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_038.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_038.jpg
Line 455: Line 453:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_040.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_040.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_041.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_041.jpg
  
  
  
=== 13. Current Regulators  ===
+
=== 13.  Linear Regulator Output Capacitor  ===
These regulators will look very similar to the 5 Volt Regulator in step 12. Identical, in fact, except that they will have the number 'LM317' on them.
 
 
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_036.jpg
 
 
 
Install these in locations U1, U2, U3, U4, U5, U6, U7, and U8. Once again, orientation matter! Be sure to line up the flat side of the regulator with the flat side of the footprint on the board (the flat side should be facing toward the top of the board).
 
 
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_037.jpg
 
 
 
 
 
 
 
=== 14.  Linear Regulator Output Capacitor  ===
 
 
This part will be a little blue blob with two leads coming out of it.
 
This part will be a little blue blob with two leads coming out of it.
  
Line 478: Line 466:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_043.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_043.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_044.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_044.jpg
  
  
=== 15. Other Capacitors ===
+
=== 14. Other Capacitors ===
 
These parts will be yellow brown blobs with two wires coming out of them, and come on paper tape (similar to the tape the transistors came in).
 
These parts will be yellow brown blobs with two wires coming out of them, and come on paper tape (similar to the tape the transistors came in).
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_046.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_046.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_047.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_047.jpg
  
Line 490: Line 480:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_049.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_049.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_048.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_048.jpg
  
  
  
=== 16. Power Indicator Lamp ===
+
=== 15. Power Indicator Lamp ===
 
The Big Digit Driver board has a power light. Nothing fancy, just a yellow LED. It goes in location LED1 - between the two IC footprint in the upper middle of the board.
 
The Big Digit Driver board has a power light. Nothing fancy, just a yellow LED. It goes in location LED1 - between the two IC footprint in the upper middle of the board.
  
Line 500: Line 491:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_050.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_050.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_051.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_051.jpg
  
  
  
=== 17. Screw Terminal Power Connectors ===
+
=== 16. Screw Terminal Power Connectors ===
 
These are the green plastic blocks with screws in the top of them. You can install them in any orientation, but it's probably better to install them with the wire slots facing outwards.
 
These are the green plastic blocks with screws in the top of them. You can install them in any orientation, but it's probably better to install them with the wire slots facing outwards.
  
Line 512: Line 504:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_055.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_055.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_054.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_054.jpg
  
Line 521: Line 514:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_057.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_057.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_056.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_056.jpg
  
  
  
=== 18. SPI headers ===
+
=== 17. SPI Headers ===
 
These are also a bit tricky. The SPI header is a two by three block of straight pins. These should drop right into locations J5 and J6, on the left-hand and right-hand side of the board. Solder one pin on the back and then flip the board over. Make sure that the header is perpendicular to the board and the black plastic block is seated on the board. Once you're sure the header is seated properly, solder the rest of the pins on the back.  
 
These are also a bit tricky. The SPI header is a two by three block of straight pins. These should drop right into locations J5 and J6, on the left-hand and right-hand side of the board. Solder one pin on the back and then flip the board over. Make sure that the header is perpendicular to the board and the black plastic block is seated on the board. Once you're sure the header is seated properly, solder the rest of the pins on the back.  
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_060.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_060.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_059.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_059.jpg
  
  
  
=== 19. DC Power Barrel Jack ===
+
=== 18. DC Power Barrel Jack ===
 
This part goes in location J4, on the right-hand side of the board.
 
This part goes in location J4, on the right-hand side of the board.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_062.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_062.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_061.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_061.jpg
  
Line 542: Line 538:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_063.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_063.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_064.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_064.jpg
  
Line 548: Line 545:
  
  
=== 20. Insert Shift Register ===
+
=== 19. Insert Shift Register ===
 
The shift register is a 16 pin IC that has '74HCT595N' on it. It is the top chip in this photo:
 
The shift register is a 16 pin IC that has '74HCT595N' on it. It is the top chip in this photo:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_066.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_066.jpg
  
You may need to fiddle with the pins a bit to get it to plug into the socket at U9. Carefully pressing the side of the pins against a flat, hard surface is a good way to do this.
+
You may need to straighten the pins to get it to plug into the socket at U9. Carefully pressing the side of the pins against a flat, hard surface is a good way to do this.
  
Orientation matters with this part! See that notch on one end of the IC? That should line up with the notch/semi-circle on the IC footprint on the board.
+
''Orientation matters:'' Notice the half-moon shaped notch on one end of the IC-- on the left end in the photo. That notch must line up with the notch on the IC footprint on the board and socket.  Insert the chip firmly and fully into the socket.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_067.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_067.jpg
Line 561: Line 558:
  
  
=== 21. Optional: Insert Schmitt Trigger ===
+
=== 20. Insert Schmitt-input buffer IC ===
If you didn't install the Schmitt trigger bypass jumpers in step 8 you should install the Schmitt trigger at this point.
+
The Schmitt-input buffer IC is the 14 pin chip that has 'SN74ACT14N' written on it. It is the bottom chip in this photo.
 
 
The Schmitt trigger is the 14 pin IC that has 'SN74ACT14N' written on it. It is the bottom chip in this photo.
 
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_066.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_066.jpg
  
The schmitt trigger and it goes in location U10. Like the shift register, orientation matters: the notch on one end of the IC should line up with the notch/semi-circle on the IC footprint on the board.
+
Install this chip at location U10. ''Orientation matters:''  Again, the notch on the IC must line up with the notch on the IC footprint on the board and socket.  Insert the chip firmly and fully into the socket.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_068.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_068.jpg
Line 574: Line 569:
  
  
=== 22. Display connector ===
+
=== 21. Display connector ===
 
Almost done!
 
Almost done!
  
Line 580: Line 575:
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_069.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_069.jpg
 +
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_070.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_070.jpg
  
Line 591: Line 587:
  
  
=== 23. You're done with the electrical stuff! ===
+
 
 +
=== 22. You're done with the electrical stuff! ===
 
Good work, the board is finished. Now lets get it attached to a display, eh?
 
Good work, the board is finished. Now lets get it attached to a display, eh?
  
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_079.jpg
+
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_094.jpg
 +
 
 +
We'll be installing an insulator to prevent the Big Digit Driver board from coming on contact with the display and causing a short circuit. We'll also be attaching metal standoffs to the back of the display for mounting purposes.
  
  
=== 24. Attach The Display ===
+
=== 23. Attach The Display ===
 
The driver board slides onto the back of the display. Plugging the display into the edge connector should do a pretty good job lining up the mounting holes.
 
The driver board slides onto the back of the display. Plugging the display into the edge connector should do a pretty good job lining up the mounting holes.
  
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_080.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_080.jpg
  
=== 25. Delrin Insulator ===
+
 
 +
 
 +
=== 24. Delrin Insulator ===
 
The plastic insulator goes between the driver board and display. Note that the insulator has two holes - these line up with the middle pair of holes on the driver board (specifically, the holes that are slightly farther from the edges than the other four and line up with the mounting holes in the display).
 
The plastic insulator goes between the driver board and display. Note that the insulator has two holes - these line up with the middle pair of holes on the driver board (specifically, the holes that are slightly farther from the edges than the other four and line up with the mounting holes in the display).
  
Line 610: Line 611:
  
  
=== 26. Board Spacers And Standoffs - Bottom of Display ===
+
 
To secure the driver board to the display we use a 1/8 inch nylon washer, 1/2 inch long 6-32 screw, and a 3/4 inch threaded standoff. The washer goes between the display and the driver board, either on top of or under the Delrin insulator (your choice). Pass the 1/2 inch screw through the display board, insulator, washer, and driver board. Screw the standoff onto it.
+
=== 25. Board Spacers And Standoffs - Bottom of Display ===
 +
To secure the driver board to the display we use a 1/8 inch (3.2mm) thick nylon washer, 1/2 inch (12.7mm) long 6-32 screw, and a 3/4 inch (19mm) tall threaded standoff. On the bottom corners, pass a screw through the display board, insulator, washer, and driver board. Screw a standoff onto it.
 +
 
 +
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_091.jpg
 +
 
 +
 
 +
 
 +
=== 26. Board Spacers And Standoffs - Top of Display ===
 +
To match the height of the stack-up on the bottom of the display, use the 1/16 inch (1.6mm) thick nylon washer, 7/8 inch (22.2mm) tall threaded standoff, and 1/2 inch (12.7mm) long 6-32 threaded screw. On the top corners, pass a screw through the display board and washer. Screw a standoff onto it.
 +
 
 +
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_088.jpg
  
  
=== 27. Board Spacers And Standoffs - Top of Display ===
 
To match the height of the stack-up on the bottom of the display, use the 1/16 inch nylon washer, 7/8 inch threaded standoff, and 3/8 inch 6-32 threaded screw. Pass the 3/8 inch screw through the display board and washer, and screw the standoff onto it.
 
  
 +
=== 27. Really done this time! ===
 +
That's it, you're completely done with assembly! You're ready to mount it and get started using it! The kit includes four extra 1/2 inch 6-32 screws for mounting purposes. Next you can head over to [[Using_The_Big_Digit_Driver|Using The Big Digit Driver]].
  
=== 28. Really done this time! ===
+
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_092.jpg
That's it, you're completely done! Hang it on a wall and plug it in! The kit includes four extra 1/2 inch 6-32 screws for mounting purposes.
 
  
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_082.jpg
 
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_083.jpg
 
http://evilmadscience.s3.amazonaws.com/wiki/bdd/v0.9/assy/bdd_083.jpg

Latest revision as of 14:03, 15 November 2012

This page walks through the basic assembly process for building the Big Digit Driver.

Bill of Materials, or, "What's in the kit?"[edit]

Line Ref Des Description Type Vendor Part Number Quantity/Board
1 N/A Printed circuit board Big Digit Driver board Evil Mad Scientist LLC N/A 1
2 R25 24 ohm resistor Carbon film resistor, 1/4 watt Digikey 24QBK-ND 1
3 R1 - R5 68 ohm resistor Carbon film resistor, 1/4 watt DigiKey 68QBK-ND 5
4 R11,R13,R15,R17,R19,R21,R23 16 ohm resistor Carbon film resistor, 1/4 watt Digikey 16QBK-ND 7
5 R12,R14,R16,R18,R20,R22,R24,R26,R27 1 k resistor Carbon film resistor, 1/4 watt Digikey 1.0KQBK-ND 9
6 D1, D2 10 V, 1 W zener diode 1N4740A Digikey 1N4740A-ND 2
7 U9 IC Socket for shift register 16 pin DIP, 0.3" spacing Digikey A100206-ND 1
8 U10 IC Socket for buffer IC 14 pin DIP, 0.3" spacing Digikey 3M5462-ND 1
9 JP1 - JP3: DO NOT POPULATE Leave Empty! Zero ohm jumpers Digikey 0.0QTR-ND 2
JP4, JP5 SPI Ground Jumpers
10 Q1 - Q8 40V NPN Transistor 2N3904, 40V Digikey 2N3904-APCT-ND 8
11 U1 thru U8 Adjustable Linear Regulator LM317L, 100 mA Digikey LM317LZ-ND 8
12 U11 5V Linear Regulator TL750L05, 150 mA Digikey 296-8002-5-ND 1
13 C2 Bypass Capacitor, 10 uF Ceramic Capacitor Digikey 445-4816-ND 1
14 C1, C3, C4 Bypass Capacitors, 0.1 uF Ceramic Capacitor, 25 V Digikey BC1148TR-ND 3
15 LED1 Indicator LED 3mm yellow diffused-lens Digikey 754-1212-ND 1
16 J2, J3 Screw Terminal 2 position euro-style 3. 5mm DigiKey ED2635-ND 2
17 J5, J6 6-pin SPI interface headers 0.1" DIL Header Digikey 609-3202-ND 2
18 J4 Power Jack, high current 2.1 mm ID Barrel Jack Digikey CP-002AH-ND 1
19 U9 Shift Register IC 74HCT595, DIP-16 Digikey 568-1560-5-ND 1
20 U10 Schmitt-input "buffer" IC 74ACT14, DIP-16 Digikey 296-4368-5-ND 1
21 J1 Display Connector (card edge) 11 Position/22 Contact 0.156" pitch Digikey EBM11DSAN-ND 1
22 N/A Standoffs (for digit top) Round, threaded 6-32 x 7/8" Digikey 1848K-ND 2
23 N/A Display/Driver Board Standoffs Round, threaded 6-32 x 3/4" DigiKey 3488K-ND 2
24 N/A Spacers (for digit top) #6 x 1/16" nylon washers McMaster-Carr 90295A090 2
25 N/A Display/Driver Board spacer #6 x 1/8" nylon washer McMaster-Carr 94639A407 2
26 N/A Mounting Screws Button Socket Cap Screw, 6-32 x 1/2" McMaster 92949A148 8
27 N/A Delrin Insulator Delrin Insulator Evil Mad Scientist LLC N/A 1
28 N/A Ribbon Cable 12 inch 6-pin Ribbon cable Evil Mad Scientist LLC 562 1

Assembly procedure[edit]

This document will show you where each part goes.

This guide assumes that you have had some soldering experience. If not, or it's been a while, you may also want to look at pages 2 and 5-7 of the Bulbdial clock assembly instructions, which go over basic tools and technique. And, if you really are a beginner, there are plenty of good tutorials on line, like this one.


1. The circuit board[edit]

Here's what the empty printed circuit board looks like:

bdd_001.jpg

bdd_002.jpg

We'll be adding components to the labeled locations there.

When we refer to locations on the board and say things like 'look on the left-hand side of the board', we assume the board is being held with the silk-screen side up (we'll be calling this the 'front side') and with the text right side up.


2. Decimal Point Current Sense Resistor[edit]

Let's start with an easy one! Locate the 24 ohm resistor (color code: Red/Yellow/Black/Gold).

bdd_003.jpg

Bend the leads as shown.

bdd_004.jpg

This will go in location R25 - it's right above the power jack footprint on the right-hand side of the board (location J4).

bdd_005.jpg

Drop it in place (location R25), and bend the leads over by about forty-five degrees on the back of the board. With these resistors the orientation doesn't matter.

bdd_006.jpg

Solder the leads and clip off the extra wire.

bdd_007.jpg

bdd_008.jpg

This is the general procedure we'll follow for all the parts in this kit.

bdd_009.jpg


3. Decimal Point Load Resistors[edit]

Next, we'll be installing 68 ohm resistors (color code: Blue/Gray/Black/Gold) in locations R1 through R5.

bdd_010.jpg

All of these locations are immediately to the left of the power jack footprint on the right-hand side of the board.

bdd_012.jpg

Bend the leads...

bdd_011.jpg

Drop in place, bend the leads over on the backside...

bdd_013.jpg

Solder and clip!

bdd_014.jpg

bdd_015.jpg


4. Other Current Sense Resistors[edit]

Getting the hang of this? Great!

Next, let's install the 16 ohm (color code: Brown/Blue/Black/Gold) resistors. These come as a segment from a large spool. Just pull them straight out and straighten the leads as needed.

bdd_016.jpg

Installation procedure for these is exactly the same as the resistors above. These will go in locations R11, R13, R15, R17, R19, R21, and R23 (in a big line across the middle of the board). Here's what they look like when installed:

bdd_017.jpg


5. Base Resistors[edit]

Next, locate all the 1k ohm resistors (color code: Brown/Black/Red/Gold).

bdd_018.jpg

Install them into locations R12, R14, R16, R18, R20, R22, R24, and R26 (again, in a line across the middle of the board, right above the resistors we installed in step 4). You may have noticed that we didn't use all the 1k ohm resistors available. Thats okay, we'll use the last one in step 6!


6. LED Resistor[edit]

Last resistor, we promise!

It's a 1k ohm (Brown/Black/Red/Gold), exactly like the resistors in step 5. This resistor goes in location R27, between the large IC footprint near the top-middle of the board.

This is what your board should look like now:

bdd_020.jpg


7. Zener Diodes[edit]

Be careful with these - the resistors we installed above could be installed in any orientation, but not so with these diodes!

Look at the board for a second, and locate locations D1 and D2 (upper left-hand side of the board). Notice the thick white lines inside the footprint, on the left of the box?

bdd_022.jpg

Take a look at the diodes. See how they have a black line wrapped around one end of the glass cylinder?

bdd_021.jpg

These are polarity markings - when installing these parts you need to match up the black line on the diode with the white line on the footprint, like so:

bdd_023.jpg

Installing the diode backward could cause your Big Digit Driver to be damaged when you plug it in! Double check the orientation of your diodes before you solder them.

Other than keeping an eye on the polarity, installing the diodes is pretty much the same as the resistors we installed above.


8. SPI Header Ground Jumpers[edit]

Next, we will install the jumpers that connect the Big Digit Driver to the SPI ground line. For this we'll use zero ohm wire jumpers, which look like resistors with a single black stripe instead of four or more. (If you should need additional jumpers beyond those included with the kit, you can use plain wire as a substitute.)

bdd_030.jpg

We'll be installing them in locations JP5 (upper left-hand side of the board, just below the diodes) and JP4 (upper right-hand side of the board). Here is what they look like when installed.

bdd_031.jpg

bdd_090.jpg


Please note that locations JP1, JP2, and JP3 are normally left unpopulated.

(Aside: Jumpers at JP1-JP3 can be used to bypass the Schmitt-input "buffer" chip. Even though some of our photos do show these installed, please leave JP1-JP3 empty unless you really know what you're doing. If for a good reason you do install jumpers in JP1-JP3, you must not install the Schmitt-input "buffer" IC in location U10, and instead leave that socket empty.)


9. Shift Register and Schmitt-input "Buffer" Sockets[edit]

Next, we will install the sockets for the ICs.

bdd_024.jpg

There are two IC footprint (U9 and U10) and they are slightly different sizes (U9 is 16 pins, and U10 is 14 pins). Make sure you have the right socket for the right footprint! If it doesn't drop in, or if the socket doesn't seem to cover the entire footprint, double check that you have the correct socket.

Take a look at the board - notice the 'notch'/semicircle on one end of the footprint outline? This is a polarity marking. Match this mark with the notch in the end of of the socket.

bdd_025.jpg

Drop the socket into its respective footprint and flip the board over (you can either hold the socket in place or use the surface of a table/desk/bench to hold it in place). Now there is a bit of a trick to getting the socket flush the with the board. First, we bend over two pins in order to hold the socket mostly in place - notice how the bent pins are on opposite rows and opposite ends of the footprint.

bdd_026.jpg

Then, solder TWO pins - either the two bent pins or the pins directly across from them. Flip the board over and check that the socket is flush with the board. If not, apply light pressure to the socket on the 'high' end and reheat the solder joint. The socket should 'snap' into place. Remember to give the solder a moment to cool before you take your hand away!

At this point you can solder the rest of the pins. Trim what excess you can - it'll save wear-and-tear on the insulator when you mount the display.

bdd_027.jpg

bdd_028.jpg

Then repeat for the other socket.

bdd_029.jpg


10. Digital Control Transistors[edit]

These transistors are little black cylinders with one side flattened and have three leads coming out one end. They should come attached to a strip of paper tape, but double check their markings just to be sure. They should have the number '2N3904' on the flattened side of the cylinder.

bdd_033.jpg

bdd_034.jpg

We will be installing these into locations Q1, Q2, Q3, Q4, Q5, Q6, Q7, and Q8 (in a line across the middle of the board). Note that orientation matters! Take a look at the board. See how the footprint is a circle with a flat side? That flat side matches up with the flat side on the part itself (the side with the text on it) - in other words, the flat side of the part should be facing toward the top of the board.

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You may have noticed that the transistors also come with pre-bent leads - all you need to do is cut them loose from the paper strip and drop them in place.


11. Current Regulators[edit]

These will look similar to the transistors in step 10, except that they will have the number 'LM317' on them, do not come attached to paper tape, and do not have their leads pre-bent.

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Install these in a line just below the transistors, in locations U1, U2, U3, U4, U5, U6, U7, and U8. Once again, orientation matters! Be sure to line up the flat side of the regulator with the flat side of the footprint on the board (the flat side should be facing toward the top of the board).

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12. Five Volt Linear Regulator[edit]

This part will look look identical to the current regulators in step 11, except that they will have the number '750L05' on them.

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Make sure you have the right part! There is only one voltage regulator and it will look very similar to the current regulators used in step 13. We will install this part in location U11 (upper left-hand side of the board, look for the words '5 Volt Regulator').

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Like with the transistors in step 11, orientation matters! Again, line up the flat side of the regulator with the flat side of the footprint on the board (the flat side should be facing toward the top of the board). Getting the leads into the proper holes may prove a bit tricky - you may want to pre-bend them yourself before attempting to install the part.

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13. Linear Regulator Output Capacitor[edit]

This part will be a little blue blob with two leads coming out of it.

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We'll be installing it in location C2 (look in the upper left-hand side of the board, under the '5 Volt Regulator' label). Don't worry about orientation.

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14. Other Capacitors[edit]

These parts will be yellow brown blobs with two wires coming out of them, and come on paper tape (similar to the tape the transistors came in).

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These will go in locations C1, C3, and C4. Orientation doesn't matter with these parts, so you can just drop them in.

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15. Power Indicator Lamp[edit]

The Big Digit Driver board has a power light. Nothing fancy, just a yellow LED. It goes in location LED1 - between the two IC footprint in the upper middle of the board.

Note that orientation matters for this part: the long lead goes into the square hole.

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16. Screw Terminal Power Connectors[edit]

These are the green plastic blocks with screws in the top of them. You can install them in any orientation, but it's probably better to install them with the wire slots facing outwards.

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These go in locations J2 and J3, on either sides of the board.

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Getting them to stay in place when solder is a bit tricky - we recommend placing the connector pins-up on a flat surface and laying the board onto it.

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Only solder one pin at first. Check to make sure the connector is lined up correctly before soldering the other pin.

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17. SPI Headers[edit]

These are also a bit tricky. The SPI header is a two by three block of straight pins. These should drop right into locations J5 and J6, on the left-hand and right-hand side of the board. Solder one pin on the back and then flip the board over. Make sure that the header is perpendicular to the board and the black plastic block is seated on the board. Once you're sure the header is seated properly, solder the rest of the pins on the back.

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18. DC Power Barrel Jack[edit]

This part goes in location J4, on the right-hand side of the board.

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Use the solder sparingly - just enough to tack it down. Flooding the holes may cause solder to bridge the gap between the holes and cause a short circuit.

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19. Insert Shift Register[edit]

The shift register is a 16 pin IC that has '74HCT595N' on it. It is the top chip in this photo:

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You may need to straighten the pins to get it to plug into the socket at U9. Carefully pressing the side of the pins against a flat, hard surface is a good way to do this.

Orientation matters: Notice the half-moon shaped notch on one end of the IC-- on the left end in the photo. That notch must line up with the notch on the IC footprint on the board and socket. Insert the chip firmly and fully into the socket.

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20. Insert Schmitt-input buffer IC[edit]

The Schmitt-input buffer IC is the 14 pin chip that has 'SN74ACT14N' written on it. It is the bottom chip in this photo.

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Install this chip at location U10. Orientation matters: Again, the notch on the IC must line up with the notch on the IC footprint on the board and socket. Insert the chip firmly and fully into the socket.

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21. Display connector[edit]

Almost done!

This part is the huge blue card edge socket with pins at a right angle. It goes in location J1.

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Make sure you put it in the correct side of the board! The socket actually sits on the back of the board, not the front (i.e. not the side with all the other components). The connector faces 'upwards', toward the top of the board.

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Make sure the socket is completely seated on the board before you solder it down. Clip off any excess wire.

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22. You're done with the electrical stuff![edit]

Good work, the board is finished. Now lets get it attached to a display, eh?

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We'll be installing an insulator to prevent the Big Digit Driver board from coming on contact with the display and causing a short circuit. We'll also be attaching metal standoffs to the back of the display for mounting purposes.


23. Attach The Display[edit]

The driver board slides onto the back of the display. Plugging the display into the edge connector should do a pretty good job lining up the mounting holes.

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24. Delrin Insulator[edit]

The plastic insulator goes between the driver board and display. Note that the insulator has two holes - these line up with the middle pair of holes on the driver board (specifically, the holes that are slightly farther from the edges than the other four and line up with the mounting holes in the display).

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Be careful with the insulator! It is resistant against punctures, but is actually rather brittle. Don't twist or warp it unnecessarily.


25. Board Spacers And Standoffs - Bottom of Display[edit]

To secure the driver board to the display we use a 1/8 inch (3.2mm) thick nylon washer, 1/2 inch (12.7mm) long 6-32 screw, and a 3/4 inch (19mm) tall threaded standoff. On the bottom corners, pass a screw through the display board, insulator, washer, and driver board. Screw a standoff onto it.

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26. Board Spacers And Standoffs - Top of Display[edit]

To match the height of the stack-up on the bottom of the display, use the 1/16 inch (1.6mm) thick nylon washer, 7/8 inch (22.2mm) tall threaded standoff, and 1/2 inch (12.7mm) long 6-32 threaded screw. On the top corners, pass a screw through the display board and washer. Screw a standoff onto it.

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27. Really done this time![edit]

That's it, you're completely done with assembly! You're ready to mount it and get started using it! The kit includes four extra 1/2 inch 6-32 screws for mounting purposes. Next you can head over to Using The Big Digit Driver.

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