> For the complete documentation index, see [llms.txt](https://khalil-lab.gitbook.io/evolver/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://khalil-lab.gitbook.io/evolver/hardware/smart-sleeve/vial-board.md).

# Vial Board

## Version D

<figure><img src="/files/WLJCcPxtyqnnwG8ku1AY" alt=""><figcaption><p>Picture of version D vial board in KiCAD</p></figcaption></figure>

### Pin Map

*Differences to Version C bolded*

1. Fan
2. Unused; linked to fan for future fan tachometer
3. Heating resistor
4. Thermistor
5. OD IR LED
6. **OD 135 photodiode**
7. **OD 90 photodiode / Spare A**
8. Spare B

<figure><img src="/files/5vDVzBPQhjQ0nryrreMJ" alt=""><figcaption><p>Differences to vial board revision C inside box.</p></figcaption></figure>

## Version C

<figure><img src="/files/6w1mfUJBDWKqpLaxed9P" alt=""><figcaption><p>Picture of version C vial board in KiCAD</p></figcaption></figure>

### Pin Map

*Differences to Version D bolded*

1. Fan
2. Unused; linked to fan for future fan tachometer
3. Heating resistor
4. Thermistor
5. OD IR LED
6. **OD 90 photodiode**
7. **OD 135 photodiode / Spare A**
8. Spare B

<figure><img src="/files/KeYSbDBipJzc57qrIHpR" alt=""><figcaption><p>Differences to vial board revision D inside box.</p></figcaption></figure>