1. MCU

Looks like the **ESP32-WROOM-32** will work swimmingly. Pinout is as follows:

| Peripheral       | Pin Assignment | GPIO Number | Notes/Functions                      |
| ---------------- | -------------- | ----------- | ------------------------------------ |
| Analog Input 1   | SENSOR_VP      | 36          | ADC1_CH0, input-only                 |
| Analog Input 2   | SENSOR_CAPP    | 37          | ADC1_CH1, input-only                 |
| Analog Input 3   | SENSOR_CAPN    | 38          | ADC1_CH2, input-only                 |
| Analog Input 4   | SENSOR_VN      | 39          | ADC1_CH3, input-only                 |
| Digital Output 1 | IO25           | 25          | General I/O, output-capable          |
| Digital Output 2 | IO26           | 26          | General I/O, output-capable          |
| Digital Output 3 | IO27           | 27          | General I/O, output-capable          |
| Digital Output 4 | MTCK/IO13      | 13          | General I/O, output-capable          |
| Digital Output 5 | MTMS/IO14      | 14          | General I/O, output-capable          |
| Digital Output 6 | MTDO/IO15      | 15          | General I/O, output-capable          |
| Digital Input 1  | VDET_1         | 34          | General input, input-only            |
| Digital Input 2  | VDET_2         | 35          | General input, input-only            |
| I2C SDA          | IO21           | 21          | I2C data, configurable               |
| I2C SCL          | IO22           | 22          | I2C clock, configurable              |
| CAN TX           | IO4            | 4           | TWAI TX, connects to transceiver TXD |
| CAN RX           | IO5            | 5           | TWAI RX, connects to transceiver RXD |
| RTC Crystal XP   | 32K_XP         | 32          | 32.768 kHz crystal for RTC           |
| RTC Crystal XN   | 32K_XN         | 33          | 32.768 kHz crystal for RTC           |

GPIO0, 2, 12, 16, 17, 18, 19, 23 are available for future expansion.

2. CAN Bus
	1. Just need a 3.3V CAN Transceiver - **SN65HVD231DR** 
	2. Connector - M12 bulkhead? BoardLock bulkhead?
		1. https://www.digikey.com/en/products/filter/circular-connectors/circular-connector-assemblies/436?s=N4IgjCBcoGwJxVAYygMwIYBsDOBTANCAPZQDaIAzABwUDscMIh1dcEAuoQA4AuUIAZR4AnAJYA7AOYgAvoXi1EIFJAw4CxMpQCscOFUXNdegCxMdeveYowADLe1Vrd2zAjMXMAEzP7MRh62YGBOgWBe7pR24WZhdL5g2toJdr5etoZRtukI8tq0XibJnCC8-EJiUrKEALQ%2B0MpQIgCuGiSQ5MUyciCMDaIAJvw1YEHmZZAg5jwAnly4-OjYKN1AA
		2. T4140012081-000 $13.09
		3. RTS712ND4S03 $15.97
		4. https://www.digikey.com/en/products/filter/circular-connector-assemblies/436?s=N4IgjCBcoGwJxVAYygMwIYBsDOBTANCAPZQDaIAzABwUDscMIhALGGFXLSALqEAOAFyggAygIBOASwB2AcxABfQgFpmiECkgYcBEADdpaLHkIlI5GOwo9%2BQyCEUqATOs0SArrrPkArDwVKIIzQIJIAJsLKYAAMELbCTCACAJ58uMLo2CgBQA
		5. 54-00216 $4.80 (4p male)
		6. 54-00235 $5.05 (4p female)
		7. I think we're gonna end up at M12 connectors for sensors and flying pigtails for motors

3. Voltage Regulator
	1. Most of the time will be spent sleeping. A low quiescent current, then, is actually more important than live current, perhaps?
	2. **TLV1117-33IDCYR** would work but emits 4.35W at 500mA - thermals need looked into for this.
	3. **TPS629210DRLR** is also good. Just need 2 resistors and an inductor as well. Good cost. Probably better.
		1. 4.7 uF input cap
		2. 22 uF output cap
		3. 2.2 uH inductor - **BDCD002520122R2MS1** (1008 case)

4. RTC (use builtin to MCU)
	1. Need ext. osc: **CM315D32768DZFT** (2-SMD package)

5. Jack Motor  - 1 AI, 2 DO
	1. Motor:  **RP-785615**
	2. Motor connector:  **AT06-2S**
	3. Motor to cable connector:  **AT04-2P**
	4. Cable: **16/2 PVC jacket cable**
	5. Cable to Control Box: **PG9 Cord Grip + Faston Tabs**
	6. Relays (2):  **A161CS12VDC.64** (25A current, 53.3 mA coil)
	7. Relay driver: **2N7002AK-Q** (240 mA max) (TO-236AB, TO-236-3, SC-59, SOT-23-3 package)
	8. Fuse:  **20A ATO fuse**
	9. Current sensor: **ACS37042KLHBLT-030B3** (30A max, -030B5 exists which is a 5v variant)

6. Fluffer (Accessory) Motor   - 1 AI, 2 DO
	1. Motor:  *TBD*
	2. Motor connector:  **AT06-2S**
	3. Motor to cable connector:  **AT04-2P**
	4. Cable: **16/2 PVC jacket cable**
	5. Cable to Control Box: **PG9 Cord Grip + Faston Tabs** ([1217861-1](https://www.digikey.com/en/products/detail/te-connectivity-amp-connectors/1217861-1/1148769))
	6. Relays (2):  **A161CS12VDC.64** (25A current, 53.3 mA coil)
	7. Relay driver: **2N7002AK-Q** (240 mA max)
	8. Fuse:  **20A ATO fuse** (3522-2 holder)
	9. Current sensor: **ACS37042KLHBLT-030B3** (30A max, -030B5 exists which is a 5v variant) (SOT-23W)

7. Drive Motor - 1 AI, 2 DO 
	1. Motor:  **80ZYT-12/JW-7** -OR-  **80ZYT-12/JW-3B** (50A)
	2. Motor connector:  **6mm Ring Terminals with Boots**
	3. Cable: **12/2 PVC jacket cable**  
	4. Cable to Control Box:  **PG9 Cord Grip + Faston Tabs**
	5. Relays (2):  **A31CSP12VDC2** (70A current, 150 mA coil)
	6. Relay driver: **2N7002AK-Q** (240 mA max)
	7. Fuse:  No fuse, just the fuse/breaker for the main battery
	8. Current sensor: **ACS37220LEZATR-100B3** (100A max, -100B5 exists which is a 5v variant) (7-PowerLQFN / 7-QFN)

8. Jack Limit Switch  - 1 DI
	1. Sensor:  **PBM6-AN-1H** (-1A exists also which is a 2m pigtail. -1H is a M12 connector)

9. Odometry Geartooth Sensor - 1 DI
	1. Sensor:  **PBM6-AN-1H** (-1A exists also which is a 2m pigtail. -1H is a M12 connector)

10. Solar Charging Circuit
	1. **BQ24650 charge controller**  
	2. N-channel MOSFETs (Q1 high-side, Q2 low-side): 40V-rated, low RDS(on) (e.g., 20mΩ), such as **AO3400** or equivalent, for synchronous rectification.  
	3. Inductor (L): 10µH, rated for at least 5A saturation current (e.g., Wurth **7447788220**) to support switching at 400kHz.  
	4. Current sense resistor (R\_SR): 10mΩ, 1% tolerance, 5W rating (e.g., **WSMS5515L1000FEK**) for \~4A maximum charge current (differential voltage of 40mV).  
	5. Input capacitors: 10µF ceramic (X7R, 35V) × 3, placed near MOSFETs.  
	6. Output capacitors: 4.7µF ceramic (X7R, 25V) × 2, near the battery connection.  
	7. Schottky diodes: For reverse protection (e.g., **1N5819**) and status indication.  
	8. Resistors for voltage setting: Precision 1% types (e.g., R1 \= 100kΩ, R2 \= 576kΩ for 14.4V regulation).  
	9. Optional: LEDs and resistors for charge status (e.g., bulk/absorption indication).

11. Battery - 1 AI
	1. Battery: **TL1212**
	2. Battery to cable conn: **Female Fastons**
	3. Cable: **12/2 PVC jacket cable with fuseholder**
	4. Cable to control box: **PG9 Cord Grip + Faston Tabs**
	5. Voltage divider to sense battery voltage (goes to ESP32) - **1M + 150k resistors**

12. Display
	1. Focus LCDs **C162A-FTW-DS23** (-30 to +80C operating range)
	2. This will be driven by an I/O Expander. It could be shared with the buttons.
		1. 8 bit: **PCF8574**
		2. 16 bit: **MCP23017** - pin 7 of each 8-bit bank can only be used as an output which is odd. or PCF8575 which is a little more $. Or best yet TCA9555PWR

13. Settings Adjust Buttons (4 buttons)
	1. Option (SMD): **TL3305BF260QG**
	2. Option (THT): **TS02-66-43-BK-260-SCR-D**

14. Manual Override Buttons (4 buttons)
    1. Option A: Hardwired, with an enclosed PCB
    2. Option B: Hardwired, with simple waterproof switches
    3. Option C: Remote


| Pros of Remote                       | Pros of Hardwire                           |
| ------------------------------------ | ------------------------------------------ |
| Can operate from all around the coop | Can't lose it                              |
| Easiest cable management             | Easy to repair                             |
|                                      | No pairing required                        |
|                                      | Easy interrupt (wake from sleep)           |
|                                      | If you need to make it custom, it's easier |
|                                      | No batteries to die                        |