# digital-driver

A photoreactor driver board designed to be controlled digitally over I2C. For fabrication instructions, please see the fabrication and operation guide.

The digital driver is recommended for users who are experienced with electronics and interested in automating WPP devices.

## PCB

This PCB was designed using KiCAD version 5.
Refer to `driver.pdf` for schematic.
PCB images generated with [tracespace](https://github.com/tracespace/tracespace) follow.

<img src="./driver-.top.svg" width="100%"/>
<img src="./driver-.bottom.svg" width="100%"/>

Bill of Materials

| reference      | value         | manufacturer | part number          | price | vendors |
| :------------- | :------------ | :----------- | :------------------- | :---- | :------ |
|                | dip socket    | Mill-Max     | 110-93-308-61-001000 | $1.00 | [DigiKey](https://www.digikey.com/en/products/detail/mill-max-manufacturing-corp/110-93-308-61-001000/7734612) |
| C2             | 10u           | Yageo        | CC1206KKX7R8BB106    | $0.25 | [DigiKey](https://www.digikey.com/en/products/detail/yageo/CC1206KKX7R8BB106/5195365?s=N4IgTCBcDaIMJwIxgAwDYDSGAaB2ASgBwBCxi6IAugL5A) [Mouser](https://www.mouser.com/ProductDetail/Yageo/CC1206KKX7R8BB106/?qs=%2Fha2pyFadujG%252BB25mNGWlTAfaj3wXYmzjlPMfFLRNq4azOfH13S4tw%3D%3D) |
| C3             | 22u           | Yageo        | CC1206MKX7R7BB226    | $0.75 | [DigiKey](https://www.digikey.com/en/products/detail/yageo/cc1206mkx7r7bb226/7071713) |
| D1             | (red)         | Lite-On      | LTST-C230KRKT        | $0.25 | [DigiKey](https://www.digikey.com/en/products/detail/lite-on-inc/LTST-C230KRKT/386857?s=N4IgTCBcDaIDIBUDKCC0BhMBmADAaQCU8EQBdAXyA) [Mouser](https://www.mouser.com/ProductDetail/Lite-On/LTST-C230KRKT/?qs=%2Fha2pyFadujtt9TjjkxDnLsTSvKz5QHldTfy80PY7mPtEP7ka44l7w%3D%3D) |
| D2             | (blue)        | Lite-On      | LTST-C150TBKT        | $0.50 | [DigiKey](https://www.digikey.com/en/products/detail/lite-on-inc/LTST-C150TBKT/388526?s=N4IgTCBcDaIDIBUDKCC0BhAjAVgAwICEBpBEAXQF8g) |
| J1, J2         | i2c connector | JST          | S4B-PH-K-S(LF)(SN)   | $0.50 | [DigiKey](https://www.digikey.com/en/products/detail/jst-sales-america-inc/S4B-PH-K-S-LF-SN/926628) [Newark](https://www.newark.com/jst-japan-solderless-terminals/s4b-ph-k-s-lf-sn/connector-header-2mm-4-position/dp/38K8074) |
| J3, J4         | power input   | CUI          | PJ-002A              | $1.50 | [DigiKey](https://www.digikey.com/en/products/detail/cui-devices/PJ-002A/96962) [Mouser](https://www.mouser.com/ProductDetail/CUI-Devices/PJ-002A/?qs=WyjlAZoYn51CKfAix9Mngw%3D%3D) |
| J5             | fan connector |
| J7             | LED connector |
| PS1            | regulator     | CUI          | VXO7805-500-M-TR     | $3.00 | [DigiKey](https://www.digikey.com/en/products/detail/cui-inc/VXO7805-500-M-TR/11569188) [Newark](https://www.newark.com/cui/vxo7805-500-m-tr/non-isolated-dc-switching-regulator/dp/13AJ1536) |
| R1, R4, R6, R7 | 4.7k          | Yageo        | RC1206DR-074K7L      | $0.10 | [DigiKey](https://www.digikey.com/en/products/detail/yageo/rc1206dr-074k7l/5919134) |
| R2, R5         | 470           | Yageo        | RC1206FR-07470RL     | $0.10 | [DigiKey](https://www.digikey.com/en/products/detail/yageo/RC1206FR-07470RL/728934) |
| R3             | 10k           | Yageo        | RC1206FR-0710KL      | $0.10 | [DigiKey](https://www.digikey.com/en/products/detail/yageo/RC1206FR-0710KL/728483)  |
| U1             | microcontrol. | Microchip    | ATTINY85-20PU        | $1.50 | [DigiKey](https://www.digikey.com/en/products/detail/microchip-technology/attiny85-20pu/735469) [Newark](https://www.newark.com/microchip/attiny85-20pu/microcontroller-mcu-8-bit-attiny/dp/68T3808) |
| U2             | LED driver    | Mean Well    | LDD-1000L            | $6.00 | [DigiKey](https://www.digikey.com/en/products/detail/mean-well-usa-inc/LDD-1000L/7704722) [Allied](https://www.alliedelec.com/product/mean-well/ldd-1000l/70345765/) |

## I2C Interface

`<byte FAN SPEED>` `<byte LED INTENSITY>`

## Firmware

Find in "firmware" folder.

Use Arduino IDE.

We programmed the ATtiny85 using the sparkfun Tiny AVR Programmer: [PGM-11801](https://www.sparkfun.com/products/11801).

## Changelog

### Unprinted

#### Changed
- removed wisconsin crest logo

### Revision B

#### Fixed
- silk screen polarity markings for LED
- backwards I2C connectors

### Revision A

#### Added
- initial design