Assembly for v0.4-1.1
Assembling the circuit board
Note: These assembly instructions can also be used for Pulse Pal v1.X. Simply skip addition of the four 1k resistors in step 2.
Before assembly, ensure that you have all parts specified in the bill of materials in appropriate quantities. You will also need a soldering iron, solder, wire cutters, water, a soldering sponge, a small Phillips head screwdriver, a 4-40 tap and about one hour if this is your first time building a Pulse Pal. For one step, a small amount of krazy glue is recommended.
The order of assembly below is determined by height of the components on the board, for easy positioning during soldering.
If you are new to soldering a circuit board with ICs, see this < 2-minute video tutorial for power-tips.
First, we will solder components into the printed circuit board. It looks like this:
Figure 1: The Pulse Pal r0.4 printed circuit board
Step 1: Add filtering capacitors
Required components:
68pf Capacitors x 4. (BOM Part#8)
Instructions:
Solder the capacitors into the holes labeled C1-C4.
The board should now appear as illustrated in Figure 2.
Figure 2: The PCB after adding capacitors.
Step 2: Add resistors
Required components:
100-ohm resistors x 2...(BOM Part#4)
10K resistors x 2............(BOM Part#5)
Instructions:
Solder the 100-ohm resistors into the board holes labeled 100 (above and to the right of the input channels)
v0.4 only: Solder the 1k resistors into the board holes labeled 1k in the diagram (750-ohm in some revisions)
Solder the 10k resistors into the board holes labeled 10k (on either side of the Optocoupler)
The board should now appear as illustrated in Figure 3.
Figure 3: The PCB after adding through-hole resistors.
Step 3: Add resistor network and LEDs
Required components:
470-ohm resistor array x 1...(BOM Part#7)
Blue 3mm LEDs x6.............. (BOM Part#3)
Instructions:
Solder the resistor array into the hole labeled RN1 (below the output channels). Ensure that the dotted end of the resistor array matches the end of the silkscreen outline labeled "1"
Solder the LEDs into the holes labeled LED1 - LED6 (above each input or output channel)
The board should now appear as illustrated in Figure 4.
Figure 4: The PCB after adding the 470-ohm resistor array and LEDs.
Step 4: Add ICs
Required components: Figure 5 designation
Voltage regulator L78S10CV x1.......(BOM Part#2). Drawn in black.
Photocoupler IC TLP2530 x1................(BOM Part#13) Drawn in green.
EEPROM IC 25LC640A x1...............(BOM Part#12) Drawn in red.
DAC MAX500BCPE+ x1...................(BOM Part#10) Drawn in purple.
Op Amp TL084ACN x1.......................(BOM Part#11) Drawn in orange.
10K resistor array x1...........................(BOM Part#6) Drawn in blue.
Instructions:
Solder the ICs into their places as shown in Figure 5.
Be careful to ensure that the notch in each IC aligns with the notch drawn on the chip's white outline on the board.
If an IC does not have a notch, the "notch" end of the chip is indicated by a circular indentation.
The board should now appear as illustrated in Figure 5.
Figure 5: The PCB after adding ICs.
Step 5: Add voltage converter and 2x4 male header
Required components:
12V bipolar step-up converter x1...(BOM Part#1)
2x4 male header x1.........................(BOM Part#20)
Instructions:
Solder the voltage converter to the place indicated on the BACK FACE of the board.
This means you will be soldering leads on the front face of the board, while the voltage converter resides on its back face.
Solder the male header to the back face of the board as well. Its 2x4 array of holes is located between the DAC and the EEPROM.
The top side of the board should now appear as illustrated in Figure 6.
Figure 6: The PCB after adding the voltage converter and 2x4 male header to the board's back face.
Step 6: Add Arduino headers
Required components:
Arduino stackable header, 6-pin x2.........(BOM Part#28)
Arduino stackable header, 8-pin x4...(BOM Part#29)
Instructions:
Solder two 8-pin connectors in the row of 16 holes labeled "oLED Display i/o" (upper left of board).
Cut the leads on the back side.
For the next step, DO NOT cut the leads. These plug into the microcontroller.
Solder two 8-pin and two 6-pin headers from the header kit. The 8-pin headers are below the oLED headers, and the 6-pin headers are above the input channels.
The top side of the board should now appear as illustrated in Figure 7.
Figure 7: The PCB after adding the oLED and Arduino-kit headers.
Step 7: Add thumb joystick and BNC connectors
Required components:
Thumb joystick x1.........(BOM Part#26)
BNC connectors x6......(BOM Part#15)
Instructions:
Solder the thumb joystick (upper right of board). Aligning the pins with the holes may appear challenging at first, but can be done with a little practice.
Solder BNC connectors for input and output channels. For ideal resilience, solder only the signal (central) pin to the board, and check to ensure the connector's plastic support ridges are flush with the board. Re-melt the solder and press the connector to adjust as necessary. Once the connector is flush with the board, solder the ground and support pins.
The board should now appear as illustrated in Figure 8.
Figure 8: The PCB after adding the thumb joystick and BNC connectors.
Step 8: Add oLED stand-offs
Required components:
0.5" Male-Female stand-off x2...............(BOM Part#17)
0.625" Female-Female stand-off x2......(BOM Part#18)
Instructions:
Place the 0.5" M-F stand-offs in the holes to the upper-left and lower-left of the thumb joystick (see Figure 9). The threaded male end should pass through the board.
Screw the 0.625 F-F stand-off to the protruding male threads on the back face of the board.
The board should now be sandwiched between the 0.5" and 0.625" stand-offs, with the 0.5" stand-off on the top face of the board.
The board should appear as illustrated in Figure 9.
Figure 9: The PCB after adding the oLED stand-offs
Step 9: Add oLED screen and supporting posts
Required components:
oLED screen x1..........................................(BOM Part#14)
1x16 Male strip header x1..........................(BOM Part#21)
1/4" 4-40 screws x2....................................(BOM Part#23)
0.625" Female-Female 4-40 standoff X3... (BOM Part#18)
0.625" Male-Female 4-40 standoff X3....... (BOM Part#19)
Instructions:
Use a 4-40 tap to tap the two right-most holes on the oLED screen, as viewed with the 16 interface holes facing up.
Solder the 1x16 male strip header to the oLED screen. Pins should point away from you if you are viewing the screen.
Plug the screen into the top row of pins on the board, indicated by the text "oLED Display i/o".
Screw the screen's right-side holes into the stand-offs. In this revision, the left holes are left unsupported. This will be easier if you do not tighten the first screw until the second is in place.
Pull the screen out of the header slightly to ensure its plane is parallel with the Pulse Pal PCB.
Under the three remaining holes in the PCB corners, insert the white nylon 0.625" M-F stand-off so that the male end emerges through the PCB top.
Screw the aluminum 0.625" F-F standoffs to the male ends of the M-F stand-offs, so that the F-F stand-offs are secured on the PCB top.
The board should appear as illustrated in Figure 10.
Figure 10: The PCB after adding the oLED screen
Conclusion
A tutorial for making similar board assembly guides was provided by Josh Siegle on the Open Ephys wiki. We thank him for this contribution!
Assembling the enclosure
Before assembly, ensure that you have all 7 components of the laser cut enclosure. Remove paper masking from the acrylic. For one of the assembly steps, a small amount of krazy glue is optional and recommended.
First, ensure you have all 7 panels. Place Pulse Pal on the rear panel as shown:
Figure 11: The pulse pal enclosure parts.
Step 1: Add light pipes to enclosure face
Required components:
Light pipe x6.........(BOM Part#16)
Instructions:
Press each light pipe fully into the light holes as indicated below. A firm press will be necessary, so that the rear lip the light pipe head is flush with the enclosure surface.
Turn the face plate around, and add a drop of krazy glue to the back side of each pipe where it joins the enclosure, to secure them in place (recommended)
If glue was added, ensure that it is tack dry before step 4 (below).
The light pipe and light holes are illustrated in Figure 12.
Figure 12: Light pipe placement.
Step 2: Secure the circuit board to the rear enclosure panel.
Required components:
1/4" 4-40 screw x5.........(BOM Part#23)
Instructions:
Using 1/4" 4-40 screws, secure the circuit board to the rear enclosure panel.
The appropriate screw holes are illustrated in Figure 13.
Figure 13: Rear panel screw placement.
Step 3: Add enclosure bottom and sides.
Required components:
None
Instructions:
Stand the bottom and side panels on the enclosure rear as shown in Figure 14.
Figure 14: Addition of side panels.
Step 4: Add the enclosure face panel and bottom T-slot screws.
Required components:
1/2" 4-40 screw x6.........(BOM Part#27)
4-40 nut x4.....................(BOM Part#24)
Instructions:
Place the enclosure face panel on the front of the device. Ensure that all tabs from the bottom and side panels snugly fit through rectangular holes in the face panel. Ensure that the oLED screen is flush with the front face of the enclosure face panel.
Screw the face panel in place with 1/2" 4-40 screws. For the bottom four screws, hold the nut in the T-slot securely with your pinched fingertips while adding the screw.
The appropriate screw holes are illustrated in Figure 15.
Figure 15: Addition of the face panel and bottom T-slot screws.
Step 5: Add the enclosure top panel
Required components:
1/2" 4-40 screw x3.........(BOM Part#27)
4-40 nut x2.....................(BOM Part#24)
Instructions:
Place the enclosure top panel on the top of the device. Ensure that all tabs from the back and face panels snugly fit through rectangular holes in the top panel.
Screw the top panel in place with 1/2" 4-40 screws. For the top two screws, hold the nut in the T-slot securely with your pinched fingertips while adding the screw.
The appropriate screw holes are illustrated in Figure 16.
Figure 16: Addition of the top panel.
Step 6: Add the rack mount wing
Required components:
1/2" 4-40 screw x6.........(BOM Part#27)
4-40 nut x6.....................(BOM Part#24)
Instructions:
Place the rack mount wing behind the front panel, aligning the two clusters of three scew holes with corresponding holes in the face panel.
Screw the rack mount wing into the face panel with 1/2" 4-40 screws, placing 4-40 nuts behind the wing.
The appropriate screw holes are illustrated in Figure 17.
Figure 17: Adding the rack mount wing
Conclusion
Tighten all screws, taking care not to crack the acrylic or strip the threads from the nylon stand-offs.
Congratulations! You have just finished assembling Pulse Pal. Next, load its firmware so you can bench-test it.