# DCS2.Default Expansion

<details>

<summary><strong>Release notes</strong></summary>

**rev.1.1**

* Configuration connector slightly moved (mechanical conflict with SSD)

</details>

<figure><img src="/files/TMXrV6rNTd9L8U2UwcCc" alt=""><figcaption></figcaption></figure>

## Description <a href="#description" id="description"></a>

DCS2.Default Expansion acts as the primary interface between the Pilot Board and external drone hardware. It exposes a range of connectors and communication interfaces that allow integration with motors, sensors, payloads, and other mission-specific equipment. The board simplifies wiring and system integration by consolidating external component connections into a single expansion layer.

#### Altium sample project

{% file src="/files/3TXUL36GgF9l1K1YIORA" %}

***

## Mechanical / environmental specifications

| Attribute                       | Value/Note        |
| ------------------------------- | ----------------- |
| **Weight**                      | 51g               |
| **Dimensions** *L*×*W*×*H (mm)* | 120.5 × 52 × 14.7 |
| **Temperature rating**          | -40°C / +85°C     |
| **Conformal coating**           | Yes               |

### Dimensions <a href="#dimensions" id="dimensions"></a>

<figure><img src="/files/UJ4R734IlHHQqXKJCTid" alt=""><figcaption></figcaption></figure>

{% file src="/files/isSg1bhvauAhcaEw3v8A" %}

***

## Power supply <a href="#power-supply" id="power-supply"></a>

{% hint style="danger" %}
**WARNING - Do not exceed the maximum input voltage**

Exceeding the maximum input voltage of 60 V may result in permanent damage to the device. Ensure that the input voltage remains within the specified limits at all times.\
Special care has to be taken if voltage transients and oscillations are present, as these may cause the maximum rating to be exceeded. This can occur in systems with high inductance, during switching events, or when using motor controllers with active braking. Appropriate suppression and protection measures must be implemented.
{% endhint %}

{% hint style="danger" %}
**WARNING - Beware of excess heat**

Heat is generated by all onboard voltage regulators during operation, with dissipation increasing at higher load current and total power consumption. Adequate thermal management, such as airflow or passive cooling, is recommended when operating the board at higher load conditions to ensure proper thermal performance and prevent overheating.\
Onboard power monitoring can be used to provide a precise overview of power consumption across the whole system.
{% endhint %}

**Recommended Input Voltage Range:** 14–55 V

**Maximum Input Voltage:** 60 V

**Monitoring:** Input power rail is monitored and reported via CAN2 (DroneCAN)

### Onboard supply rails

<details>

<summary><strong>5V_CRUC/SAFE</strong></summary>

**Output voltage:** 5.13V

**Maximum current load:** 5A

Power rail monitored and reported via CAN2 (DroneCAN)

</details>

<details>

<summary><strong>5V_PERIPH</strong></summary>

**Output voltage:** 5.08V

**Maximum current load:** 8A

Controllable by onboard MCU

Power rail monitored and reported via CAN2 (DroneCAN)

</details>

<details>

<summary><strong>3V3_SOM</strong></summary>

**Output voltage:** 3.35V

**Maximum current load:** 5A

Controllable by onboard MCU

Power rail monitored and reported via CAN2 (DroneCAN)

</details>

<details>

<summary><strong>VDD_SOM</strong></summary>

**Output voltage:** 5.05V / 12.39V

(If Jetson has 5V input only, the board automatically selects lower voltage)

**Maximum current load:** 4A/3.5A

Controllable by onboard MCU

Power rail monitored and reported via CAN2 (DroneCAN)

</details>

<figure><img src="/files/XXBPx8nkvAOsBL4mXw5G" alt=""><figcaption></figcaption></figure>

***

## Peripherals <a href="#peripherals" id="peripherals"></a>

<figure><img src="/files/jTJqn6rXYq6fpXyOGZ9H" alt=""><figcaption></figcaption></figure>

***

## Connectors, controls and indicators

### Top side

<figure><img src="/files/ZElROtpodZeOp9KmxIIb" alt=""><figcaption></figcaption></figure>

#### Connectors

<details>

<summary><strong>VDD_MAIN</strong></summary>

<figure><img src="/files/wwPCr1CCoiIkruzwllFc" alt="" width="133"><figcaption></figcaption></figure>

* Matching connector XT30
* Voltage range 20-55VDC

</details>

<details>

<summary><strong>PAYLOAD SIGNALS</strong></summary>

<figure><img src="/files/AUPwI5Mas8dGMSY9WZdM" alt="" width="232"><figcaption></figcaption></figure>

Matching connector Hirose DF36-50P-0.4SD

<table><thead><tr><th width="245">pin</th><th>function</th></tr></thead><tbody><tr><td>1</td><td>GbE_DA_N</td></tr><tr><td>2</td><td>GbE_DA_P</td></tr><tr><td>3</td><td>GbE_DB_N</td></tr><tr><td>4</td><td>GbE_DB_P</td></tr><tr><td>5</td><td>GbE_DC_N</td></tr><tr><td>6</td><td>GbE_DC_P</td></tr><tr><td>7</td><td>GbE_DD_N</td></tr><tr><td>8</td><td>GbE_DD_P</td></tr><tr><td>9</td><td>CAM3_I2C_SDA</td></tr><tr><td>10</td><td>CAM3_I2C_SCL</td></tr><tr><td>11</td><td>CAM3_MCLK</td></tr><tr><td>12</td><td>CAM3_PWDN</td></tr><tr><td>13</td><td>CAM3_CLK_P</td></tr><tr><td>14</td><td>CAM3_CLK_N</td></tr><tr><td>15</td><td>CAM3_D1_P</td></tr><tr><td>16</td><td>CAM3_D1_N</td></tr><tr><td>17</td><td>CAM3_D0_P</td></tr><tr><td>18</td><td>CAM3_D0_N</td></tr><tr><td>19</td><td>CAM2_I2C_SDA</td></tr><tr><td>20</td><td>CAM2_I2C_SCL</td></tr><tr><td>21</td><td>CAM2_MCLK</td></tr><tr><td>22</td><td>CAM2_PWDN</td></tr><tr><td>23</td><td>CAM2_CLK_P</td></tr><tr><td>24</td><td>CAM2_CLK_N</td></tr><tr><td>25</td><td>CAM2_D1_P</td></tr><tr><td>26</td><td>CAM2_D1_N</td></tr><tr><td>27</td><td>CAM2_D0_P</td></tr><tr><td>28</td><td>CAM2_D0_N</td></tr><tr><td>29</td><td>USB1_PWRCTL</td></tr><tr><td>30</td><td>USB1_OC</td></tr><tr><td>31</td><td>USB1_D_P</td></tr><tr><td>32</td><td>USB1_D_N</td></tr><tr><td>33</td><td>USB1_SSTX_P</td></tr><tr><td>34</td><td>USB1_SSTX_N</td></tr><tr><td>35</td><td>USB1_SSRX_P</td></tr><tr><td>36</td><td>USB1_SSRX_N</td></tr><tr><td>37</td><td>USB0_SSTX_P</td></tr><tr><td>38</td><td>USB0_SSTX_N</td></tr><tr><td>39</td><td>USB0_SSRX_P</td></tr><tr><td>40</td><td>USB0_SSRX_N</td></tr><tr><td>41</td><td>CAN1_H (available through solder bridges)</td></tr><tr><td>42</td><td>CAN1_L (available through solder bridges)</td></tr><tr><td>43</td><td>CAN2_H (available through solder bridges)</td></tr><tr><td>44</td><td>CAN2_L (available through solder bridges)</td></tr><tr><td>45</td><td>UART_JET_TX</td></tr><tr><td>46</td><td>UART_JET_RX</td></tr><tr><td>47</td><td>JETSON_GPIOx</td></tr><tr><td>48</td><td>JETSON_GPIOx</td></tr><tr><td>49</td><td>SERIAL1_TX (available through solder bridges)</td></tr><tr><td>50</td><td>SERIAL1_RX (available through solder bridges)</td></tr></tbody></table>

</details>

<details>

<summary><strong>PAYLOAD POWER</strong></summary>

<figure><img src="/files/EpZNMvkmubS1Xn0JigZl" alt="" width="148"><figcaption></figcaption></figure>

Matching connector Molex 502578-060x

{% hint style="info" %}
VDD\_BATT rail is fused with 1A fuse
{% endhint %}

{% hint style="info" %}
5V rail is internally limited to 2A
{% endhint %}

| pin | function   |
| --- | ---------- |
| 1   | VDD\_BATT  |
| 2   | N.C.       |
| 3   | 5V\_PERIPH |
| 4   | GND        |
| 5   | GND        |
| 6   | GND        |

</details>

<details>

<summary><strong>I2C2</strong></summary>

<figure><img src="/files/ySVqmHAO6EN5R7XVZ3Qa" alt="" width="95"><figcaption></figcaption></figure>

Matching connector JST GHR-04V-S

{% hint style="info" %}
I2C2, CAN1, CAN2, ADC connectors share the same power rail internally limited to 1A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | I2C2\_SCL   |
| 3   | I2C2\_SDA   |
| 4   | GND         |

</details>

<details>

<summary><strong>CAN1</strong></summary>

Matching connector JST GHR-04V-S

{% hint style="info" %}
I2C2, CAN1, CAN2, ADC connectors share the same power rail internally limited to 1A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | CAN1\_H     |
| 3   | CAN1\_L     |
| 4   | GND         |

</details>

<details>

<summary><strong>CAN2</strong></summary>

<figure><img src="/files/a8zLFGJercODDDnHgtOB" alt="" width="97"><figcaption></figcaption></figure>

Matching connector JST GHR-04V-S

{% hint style="info" %}
I2C2, CAN1, CAN2, ADC connectors share the same power rail internally limited to 1A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | CAN2\_H     |
| 3   | CAN2\_L     |
| 4   | GND         |

</details>

<details>

<summary><strong>ADC</strong></summary>

<figure><img src="/files/Wcly8NyCJtKjqQW3hOuK" alt="" width="119"><figcaption></figcaption></figure>

Matching connector JST GHR-06V-S

{% hint style="info" %}
I2C2, CAN1, CAN2, ADC connectors share the same power rail internally limited to 1A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | 5V\_CRUCIAL |
| 3   | BAT\_ISENSE |
| 4   | BAT\_VSENSE |
| 5   | GND         |
| 6   | GND         |

</details>

<details>

<summary><strong>SERIAL5</strong></summary>

<figure><img src="/files/0aEDfcBoLx9PImpFUxYd" alt="" width="120"><figcaption></figcaption></figure>

Matching connector JST GHR-06V-S

{% hint style="info" %}
SERIAL5, GPS1, GPS2, SPI shares the same power rail internally limited to 2A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | SERIAL5\_TX |
| 3   | SERIAL5\_RX |
| 4   | S.BUS\_OUT  |
| 5   | NC          |
| 6   | GND         |

</details>

<details>

<summary><strong>GPS1</strong></summary>

<figure><img src="/files/h7qdsense6lmBlIhSBiT" alt="" width="143"><figcaption></figcaption></figure>

Matching connector JST GHR-08V-S

{% hint style="info" %}
SERIAL5, GPS1, GPS2, SPI shares the same power rail internally limited to 2A
{% endhint %}

| pin | function             |
| --- | -------------------- |
| 1   | 5V\_CRUCIAL          |
| 2   | SERIAL3\_TX          |
| 3   | SERIAL3\_RX          |
| 4   | I2C1\_SCL            |
| 5   | I2C1\_SDA            |
| 6   | SAFETY               |
| 7   | IO-LED\_SAFETY\_PROT |
| 8   | GND                  |

</details>

<details>

<summary><strong>GPS2</strong></summary>

<figure><img src="/files/zblXU0QRgPPjYbe6m0FU" alt="" width="119"><figcaption></figcaption></figure>

Matching connector JST GHR-06V-S

{% hint style="info" %}
SERIAL5, GPS1, GPS2, SPI shares the same power rail internally limited to 2A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | SERIAL4\_TX |
| 3   | SERIAL4\_RX |
| 4   | I2C2\_SCL   |
| 5   | I2C2\_SDA   |
| 6   | GND         |

</details>

<details>

<summary><strong>SPI (FMU)</strong></summary>

<figure><img src="/files/GSkEgPhaslS0z1A8oGiv" alt="" width="130"><figcaption></figcaption></figure>

Matching connector JST GHR-07V-S

{% hint style="info" %}
SERIAL5, GPS1, GPS2, SPI shares the same power rail internally limited to 2A
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | 5V\_CRUCIAL |
| 2   | SPI\_SCK    |
| 3   | SPI\_MISO   |
| 4   | SPI\_MOSI   |
| 5   | SPI\_CS0    |
| 6   | SPI\_CS1    |
| 7   | GND         |

</details>

<details>

<summary><strong>SERIAL1</strong></summary>

<figure><img src="/files/SglqZwGjQ1rK5OlZTPqd" alt="" width="119"><figcaption></figcaption></figure>

Matching connector JST GHR-06V-S

{% hint style="info" %}
5V power rail internally limited to 1A
{% endhint %}

| pin | function     |
| --- | ------------ |
| 1   | 5V\_PERIPH   |
| 2   | SERIAL1\_TX  |
| 3   | SERIAL1\_RX  |
| 4   | SERIAL1\_CTS |
| 5   | SERIAL1\_RTS |
| 6   | GND          |

</details>

<details>

<summary><strong>I2S JET</strong></summary>

<figure><img src="/files/gmAooMXXxTUoiFAHVsjw" alt="" width="121"><figcaption></figcaption></figure>

Matching connector JST GHR-06V-S

{% hint style="info" %}
5V power rail internally limited to 0.5A
{% endhint %}

| pin | function       |
| --- | -------------- |
| 1   | 5V\_CRUCIAL    |
| 2   | I2S\_JET\_DOUT |
| 3   | I2S\_JET\_DIN  |
| 4   | I2S\_JET\_FS   |
| 5   | I2S\_JET\_SCLK |
| 6   | GND            |

</details>

<details>

<summary><strong>PWM1</strong></summary>

<figure><img src="/files/c23gfLCUMMDtVCtN8vGW" alt="" width="141"><figcaption></figcaption></figure>

Matching connector JST GHR-08V-S

| pin | function                              |
| --- | ------------------------------------- |
| 1   | IO-CH1-PROT ( "PX" -> SPI\_FMU\_MISO) |
| 2   | IO-CH2-PROT ( "PX" -> SPI\_FMU\_MOSI) |
| 3   | IO-CH3-PROT ( "PX" -> SPI\_FMU\_SCK)  |
| 4   | IO-CH4-PROT ( "PX" -> SPI\_FMU\_CS1)  |
| 5   | IO-CH5-PROT ( "PX" -> SPI\_FMU\_CS2)  |
| 6   | IO-CH6-PROT                           |
| 7   | IO-CH7-PROT ( "PX" -> FMU\_CH8 )      |
| 8   | GND                                   |

</details>

<details>

<summary><strong>PWM2</strong></summary>

<figure><img src="/files/RkL59fRxOO4gk5JawHw0" alt="" width="140"><figcaption></figcaption></figure>

Matching connector JST GHR-08V-S

| pin | function                         |
| --- | -------------------------------- |
| 1   | IO-CH8-PROT ( "PX" -> FMU\_CH8 ) |
| 2   | FMU\_CH1                         |
| 3   | FMU\_CH2                         |
| 4   | FMU\_CH3                         |
| 5   | FMU\_CH4                         |
| 6   | FMU\_CH5                         |
| 7   | FMU\_CH6                         |
| 8   | GND                              |

</details>

<details>

<summary><strong>SPI_JET</strong></summary>

<figure><img src="/files/lsPc0v7I8R0ysGR1TF1z" alt="" width="137"><figcaption></figcaption></figure>

* Matching connector JST GHR-07V-S
* 3V3 SPI voltage logic

{% hint style="info" %}
SPI\_JET and CAN\_JET share the same power supply rail, internally limited to 0.5A
{% endhint %}

| pin | function        |
| --- | --------------- |
| 1   | 5V\_JET\_PERIPH |
| 2   | SPI0\_CLK       |
| 3   | SPI0\_MISO      |
| 4   | SPI0\_MOSI      |
| 5   | SPI0\_CS0       |
| 6   | SPI0\_CS1       |
| 7   | GND             |

</details>

<details>

<summary><strong>CAN_JET</strong></summary>

<figure><img src="/files/l0iZzc30QulFlwWcQZfL" alt="" width="83"><figcaption></figcaption></figure>

Matching connector JST GHR-04V-S

{% hint style="info" %}
SPI\_JET and CAN\_JET share the same power supply rail, internally limited to 0.5A
{% endhint %}

| pin | function        |
| --- | --------------- |
| 1   | 5V\_JET\_PERIPH |
| 2   | CAN\_H          |
| 3   | CAN\_L          |
| 4   | GND             |

</details>

<details>

<summary><strong>ETH1</strong></summary>

<figure><img src="/files/Z0uEb8UGZqfyuCTaBLJf" alt="" width="109"><figcaption></figcaption></figure>

Matching connector JST GHR-05V-S

| pin | function   |
| --- | ---------- |
| 1   | ETH\_RX\_N |
| 2   | ETH\_RX\_P |
| 3   | GND        |
| 4   | ETH\_TX\_N |
| 5   | ETH\_TX\_P |

</details>

<details>

<summary><strong>USB2</strong></summary>

<figure><img src="/files/HGGNPzUSOWr42zHxlqJ7" alt="" width="95"><figcaption></figcaption></figure>

Matching connector JST GHR-04V-S

{% hint style="info" %}
5V power rail internally limited to 2A
{% endhint %}

| pin | function   |
| --- | ---------- |
| 1   | 5V\_PERIPH |
| 2   | USB\_D\_N  |
| 3   | USB\_D\_P  |
| 4   | GND        |

</details>

<details>

<summary><strong>PCIE EXT</strong></summary>

<figure><img src="/files/VhgHCeVkYjMsyQgg9Jiv" alt="" width="147"><figcaption></figcaption></figure>

* FH41-20S-0.5SH connector type
* PCIE x1 bus
* Possibility to use an expansion board to the M2\_keyM connector, and use another external NVME.

{% hint style="info" %}
3V3 power rail internally limited to 2A
{% endhint %}

| pin | function      |
| --- | ------------- |
| 1   | GND           |
| 2   | TX\_P         |
| 3   | TX\_N         |
| 4   | GND           |
| 5   | RX\_P         |
| 6   | RX\_N         |
| 7   | GND           |
| 8   | CLK\_P        |
| 9   | CLK\_N        |
| 10  | GND           |
| 11  | SUSCLK 32KHZ  |
| 12  | GND           |
| 13  | #PCIE\_RST    |
| 14  | #PCIE\_CLKREQ |
| 15  | #PCIE\_WAKE   |
| 16  | 3V3\_AD       |
| 17  | 3V3\_AD       |
| 18  | 3V3\_AD       |
| 19  | 3V3\_AD       |
| 20  | 3V3\_AD       |

</details>

<details>

<summary><strong>CSI0, CAM1 (2-lanes CSI)</strong></summary>

<figure><img src="/files/XYxIV18NA7EXY2ZwLwxh" alt="" width="144"><figcaption></figcaption></figure>

* 501951-2210 connector type
* 2 lanes MIPI CSI connectors
* I2C and PWDN are 3V3 logic

{% hint style="info" %}
**Notes:**

* CAM0, CAM1 share the same power rail, internally limited to 0.5A
* JET\_CAM\_SUPPLY is configurable by the [solder bridge on the bottom side of the board](#sb3-cam-supply-select-solder-bridge)
  {% endhint %}

{% hint style="danger" %}
**WARNING**

Pay attention to the cable pins' orientation (same/opposite side contacts).

Cameras from different manufacturers can have different pin orders, so a wrong cable can cause a short-circuit!
{% endhint %}

| pin | function    |
| --- | ----------- |
| 1   | CAM\_SUPPLY |
| 2   | I2C\_SDA    |
| 3   | I2C\_SCL    |
| 4   | GND         |
| 5   | MCLK        |
| 6   | PWDN        |
| 7   | GND         |
| 8   | NC          |
| 9   | NC          |
| 10  | GND         |
| 11  | NC          |
| 12  | NC          |
| 13  | GND         |
| 14  | CSI\_CLK\_P |
| 15  | CSI\_CLK\_N |
| 16  | GND         |
| 17  | CSI\_D1\_P  |
| 18  | CSI\_D1\_N  |
| 19  | GND         |
| 20  | CSI\_D0\_P  |
| 21  | CSI\_D0\_N  |
| 22  | GND         |

</details>

<details>

<summary><strong>LED_FR_L</strong></summary>

<figure><img src="/files/yiWYlkKmpLqemtWWIRYR" alt="" width="77"><figcaption></figcaption></figure>

Matching connector JST GHR-03V-S

{% hint style="info" %}
LED\_FR\_L, LED\_FR\_R connectors share the same power rail internally limited to 2A
{% endhint %}

| pin | function   |
| --- | ---------- |
| 1   | GND        |
| 2   | LED\_FL    |
| 3   | 5V\_PERIPH |

</details>

<details>

<summary><strong>LED_FR_R</strong></summary>

<figure><img src="/files/gbUmo598PBFyVobDokUe" alt="" width="72"><figcaption></figcaption></figure>

Matching connector JST GHR-03V-S

{% hint style="info" %}
LED\_FR\_L, LED\_FR\_R connectors share the same power rail internally limited to 2A
{% endhint %}

| pin | function   |
| --- | ---------- |
| 1   | GND        |
| 2   | LED\_FR    |
| 3   | 5V\_PERIPH |

</details>

<details>

<summary><strong>LED_BK_L</strong></summary>

<figure><img src="/files/an6wEcuWCCpmC0i5ucIK" alt="" width="77"><figcaption></figcaption></figure>

Matching connector JST GHR-03V-S

{% hint style="info" %}
LED\_BK\_L, LED\_BK\_R connectors share the same power rail internally limited to 2A
{% endhint %}

| pin | function   |
| --- | ---------- |
| 1   | GND        |
| 2   | LED\_RL    |
| 3   | 5V\_PERIPH |

</details>

<details>

<summary><strong>LED_BK_R</strong></summary>

<figure><img src="/files/QkcliT0GHtLuvrCeOlYK" alt="" width="73"><figcaption></figcaption></figure>

Matching connector JST GHR-03V-S

{% hint style="info" %}
LED\_BK\_L, LED\_BK\_R connectors share the same power rail internally limited to 2A
{% endhint %}

| pin | function   |
| --- | ---------- |
| 1   | GND        |
| 2   | LED\_RR    |
| 3   | 5V\_PERIPH |

</details>

#### Indicators

<details>

<summary><strong>LED1 /LED2</strong></summary>

<figure><img src="/files/avX7Tv6Nff8oybSBBC92" alt="" width="77"><figcaption></figcaption></figure>

Power management unit activity LEDs

</details>

#### Controls

<details>

<summary><strong>JP1</strong> (Jumper 0603 footprint)</summary>

<figure><img src="/files/3K7mTQvKtlojPJUBkPx5" alt="" width="46"><figcaption></figcaption></figure>

Soldered jumper connects CAN1 to Payload connector

</details>

<details>

<summary><strong>JP2</strong> (Jumper 0603 footprint)</summary>

<figure><img src="/files/9QbgEvLssRLF9I0HenYu" alt="" width="69"><figcaption></figcaption></figure>

Soldered jumper connects CAN2 to Payload connector

</details>

<details>

<summary><strong>Button</strong> (tactile switch)</summary>

<figure><img src="/files/3vPdZa1B7Pwva6OOAddX" alt="" width="105"><figcaption></figcaption></figure>

Multifunction button of the board. The main functionality is powering the board up and down.

</details>

***

### Bottom side

<figure><img src="/files/uDrYbsrpgIuTTCUGgogN" alt=""><figcaption></figcaption></figure>

#### Connectors

<details>

<summary><strong>BATTERY SIGNAL</strong></summary>

<figure><img src="/files/iYbrAroUvCinlagU78vs" alt="" width="143"><figcaption></figcaption></figure>

Matching connector JST GHR-08V-S

| pin | function    |
| --- | ----------- |
| 1   | VBAT\_INIT  |
| 2   | CAN2\_L     |
| 3   | CAN2\_H     |
| 4   | BAT\_VSENSE |
| 5   | BAT\_ISENSE |
| 6   | BUTTON      |
| 7   | PDB SWITCH  |
| 8   | GND         |

</details>

<details>

<summary><strong>CONFIG</strong></summary>

<figure><img src="/files/aUEMeTaSILeMJYTLD5DB" alt="" width="92"><figcaption></figcaption></figure>

Matching connector JST GHR-03V-S

| pin | function |
| --- | -------- |
| 1   | COM      |
| 2   | NC       |
| 3   | GND      |

</details>

<details>

<summary><strong>EXT.BTN</strong></summary>

<figure><img src="/files/D1T63RmVfaVKQ1dUHitE" alt="" width="71"><figcaption></figcaption></figure>

Matching connector JST GHR-02V-S

> Connect the [SB5](#sb5-autostart-define-solder-bridge) to start the board automatically, without the need to press the button

| pin | function |
| --- | -------- |
| 1   | GND      |
| 2   | BUTTON   |

</details>

<details>

<summary><strong>B2B POWER CONNECTOR (PDB/Power board)</strong></summary>

<figure><img src="/files/HoFC8sjRCZUjVzG1NLFb" alt="" width="187"><figcaption></figcaption></figure>

<table><thead><tr><th width="370.45045045045043">pin</th><th>function</th></tr></thead><tbody><tr><td>1</td><td>5V_PERIPH</td></tr><tr><td>2</td><td>5V_CRUCIAL</td></tr><tr><td>3</td><td>3V3_SOM</td></tr><tr><td>4</td><td>VDD_JETSON (v2.0) / 18V_SOM (v1.x)</td></tr><tr><td>5</td><td>N.C. (v2.0) / ?V_PAYLOAD (v1.x)</td></tr><tr><td>6</td><td>5V_SAFETY</td></tr><tr><td>7</td><td>GND</td></tr><tr><td>8</td><td>GND</td></tr></tbody></table>

</details>

<details>

<summary><strong>B2B SIGNAL CONNECTOR (PDB/Power board)</strong></summary>

<figure><img src="/files/leHvPodcH5XLpFs2bNff" alt="" width="132"><figcaption></figcaption></figure>

<table><thead><tr><th width="278.45045045045043">pin</th><th>function</th></tr></thead><tbody><tr><td>1</td><td>CAN1_N</td></tr><tr><td>2</td><td>CAN1_P</td></tr><tr><td>3</td><td>GND</td></tr><tr><td>4</td><td>CAN2_N</td></tr><tr><td>5</td><td>CAN2_P</td></tr><tr><td>6</td><td>JETSON_ID (v2.0) / GND (v1.x)</td></tr><tr><td>7</td><td>I2C_SCL</td></tr><tr><td>8</td><td>I2C_SDA</td></tr><tr><td>9</td><td>SERIAL 1 TX (v2.0) / RESERVED (v1.x)</td></tr><tr><td>10</td><td>SERIAL 1 RX (v2.0) / RESERVED (v1.x)</td></tr><tr><td>11</td><td>GPIO/PWM OUT 4 (v2.0) / RESERVED (v1.x)</td></tr><tr><td>12</td><td>GPIO/PWM OUT 3 (v2.0) / RESERVED (v1.x)</td></tr><tr><td>13</td><td>GPIO/PWM OUT 2 (v2.0) / RESERVED (v1.x)</td></tr><tr><td>14</td><td>GPIO/PWM OUT 1 (v2.0) / RESERVED (v1.x)</td></tr><tr><td>15</td><td>RESERVED</td></tr><tr><td>16</td><td>BAT_V_SENSE</td></tr><tr><td>17</td><td>BAT_I_SENSE</td></tr><tr><td>18</td><td>RTC_BATTERY (v2.0) / RESERVED (v1.x)</td></tr><tr><td>19</td><td>MOD_SLEEP</td></tr><tr><td>20</td><td>SYS_RST_HS</td></tr></tbody></table>

</details>

<details>

<summary><strong>B2B ADAPTER CONNECTORS</strong></summary>

<figure><img src="/files/jIMsfbzt9BQKeNbr42Ps" alt="" width="375"><figcaption></figcaption></figure>

Pinouts and reference design will be provided as an example Altium Designer project.

</details>

#### Controls

<details>

<summary><strong>SB3</strong> (CAM supply select solder bridge)</summary>

<figure><img src="/files/7zUzGhyjIeRkuP8CXImK" alt="" width="65"><figcaption></figcaption></figure>

Soldered bridge enables 5V power to both CSI camera connectors instead of 3V3.

</details>

<details>

<summary><strong>SB5</strong> (Autostart define solder bridge)</summary>

<figure><img src="/files/rOZ804EAMfDerJnYhwMi" alt="" width="53"><figcaption></figcaption></figure>

Soldered bridge enables automatic startup of the board.

</details>


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