See general assembly instructions
Note: this module does have one surface mount component. It is possible to do by hand but can be a little tricky. See U1/U6 in the bill of materials for details.
Most parts are available on Tayda (cart link, quick-order CSV).
See general components notes for more info about acquiring parts.
| Board | Reference | Part | Value | Source | Comment | |
|---|---|---|---|---|---|---|
| Front | R1, R20 | Resistor | 100kΩ | Tayda | ||
| Front | R2, R3 | Resistor | 1kΩ | Tayda | Determines output impedance. Any value is fine. | |
| Front | R4-R7 | Resistor | 10kΩ | Tayda | Determines LED brightness. You may want to use a different value if you have different LEDs. A lower value means less resistance and brighter LEDs | |
| Front | RV1-RV3 | Potentiometer | B50kΩ | Tayda, Thonk | Linear. Any value is ok – just match R13. | |
| Front | D1-D11 | LED | 3mm | Tayda | Any standard 3mm LED will work here. | |
| Front | SW1 | Rotary Encoder | EC11 series | Tayda, Amazon | ||
| Front | SW2, SW3 | Switch | TAIWAY 200CWMSP1T3B4M2 or equivalent | Tayda, Love My Switches, Thonk | SPDT ON-ON | |
| Front | J1-J6 | 3.5mm Jack | THONKICONN (a.k.a PJ398SM or PJ301M-12) | Tayda, Thonk | ||
| Both | J8-J10 | Pin headers | 2x3, 1x8, 1x8 | Tayda (Male, Female), Amazon | Solder the two boards directly together using the male headers or (recommended) make them detachable using a male/female pair. | |
| Back | J7 | - | - | Not used. Expansion points for future features | ||
| Back | J12 | IDC connector | 2x8 | Tayda | Eurorack power header. Can use two rows of male pin headers or (recommended) a shrouded connector. | |
| Back | R8-R11, R14-R15, R21 | Resistor | 100kΩ | Tayda | ||
| Back | R12, R13, R16 | Resistor | 50kΩ | Tayda | 51k is fine. R13 should be the same as RV2. | |
| Back | R17 | Resistor | 1kΩ | Tayda | Determines output impedance. Any value is fine. | |
| Back | R18 | Resistor | 15kΩ | Tayda | R18 was incorrectly labelled as a 2nd R2 in one print run. Controls the LED brightness for the 7-LED display. Unlike the bottom LEDs, which are in series with R4-R7 (at 5v), this resistor is just used as a current reference (at 5v) by the TLC5940. To match the current across all the LEDs (and therefore the brightness), R18 is calculated by R18 = 5 / ((5 - V_LED) / R4), where V_LED is the voltage drop across one of the LEDs (at the current they will receive). This can be measured or will probably be in the LED datasheet. Then, round to the nearest available resistor value; it doesn’t have to be exact. | |
| Back | R19 | Resistor | 15kΩ | Controls the available current at the -5v ref regulator. You could probably go a little higher to be more power efficient, but if the -5v voltage sags you can decrease the value. | ||
| Back | C1-C5 | Capacitor | 100nF | Tayda | Optional. Power supply noise filtering/decoupling capacitors | |
| Back | C6-C8 | Capacitor | 10uF | Tayda | Optional. Power supply noise filtering capacitors | |
| Back | A1 | Arduino Nano | v3.0 | Tayda | ||
| 🔴 | Back | U1 OR U6 | LED driver | TLC5940NT OR TLC5940PWPR | DigiKey (THT), Octopart (THT), Mouser (SMD) | TLC5940NT, the through-hole version of this part, has been discontinued and is getting somewhat hard to find at a reasonable price. The surface-mount (HTSSOP) version of this part is still in production. It is a little harder to solder than the through-hole parts but not impossible to do by hand. See this tutorial. There are footprints on the PCB for both the through-hole and surface-mount parts. Either will work. Use one or the other, not both. The TLC5941NT (also obsolete, also through-hole) should be a drop-in replacement if that is easier to find, but I haven’t tested it yet. |
| 🔴 | Back | U2 | DAC | MCP4922-E/P | DigiKey, Mouser | |
| Back | U3 | Op-amp | MCP6004 | Tayda, DigiKey | ||
| Back | U4 | Op-amp | TL072 | Tayda, DigiKey | ||
| 🔴 | Back | U5 | Voltage regulator | LM4040BIZ-5 | DigiKey, Mouser | 5V, TO92-3 package. Alternatively, you can use the 10V version and double R9 and R14. |
🔴 = Missing from Tayda BOM