Custom Raspberry Pi Add-on ADC board (based on the Galactic Aztec Raspberry Pi Add-on: Pressure Transducer Interface board) used to read pressures on the Galactic Aztec Heavy rocket. The board has a molex connector for power input (Supply Voltage) and 6 ethernet ports for interfacing with custom pressure transducer connector boards.
Custom EagleCAD parts on this board can be found in the SDSU Rocket Eagle Libraries.
| Input | IC |
|---|---|
| A0 | ADS1114 |
| A1 | ADS1114 |
| A2 | ADS1114 |
| A3 | ADS1114 |
| A4 | ADS1100 |
| A5 | ADS1100 |
16-bit, 860 SPS ADC
| PGA | Resolution (V) | Maximum Input (V) |
|---|---|---|
| 2/3 | 0.0001875 | 5.3 |
| 1 | 0.000125 | 4.096 |
| 2 | 0.0000625 | 2.048 |
| 4 | 0.00003125 | 1.024 |
| 8 | 0.000015625 | 0.512 |
| 16 | 0.0000078125 | 0.256 |
| Bits | Resolution (V) | Sample Rate (SPS) |
|---|---|---|
| 16 | 0.000152587891 | 8 |
| 15 | 0.000305175782 | 16 |
| 14 | 0.000610351563 | 32 |
| 12 | 0.00244140625 | 128 |
Resolution values listed with PGA=1
The ethernet ports adhere to the following T-568B wiring configuration:
| Pin | Color | Function |
|---|---|---|
| 1 | Orange/White | Signal |
| 2 | Orange | Signal |
| 3 | Green/White | |
| 4 | Blue | Supply Voltage |
| 5 | Blue/White | Supply Voltage |
| 6 | Green | |
| 7 | Brown/White | Ground |
| 8 | Brown | Ground |
| Qty | Name | Description | Notes | Part Number | Vendor |
|---|---|---|---|---|---|
| 1 | H0 | Header Stacking 2x20 Tall 23mm | 1979 | Adafruit | |
| 1 | P0 | Molex Mini Fit Jr. 4-pos Right Angle | WM1352-ND | DigiKey | |
| 6 | JP0-5 | Jack RJ45 CAT5/CAT5e | 380-1046-ND | DigiKey | |
| 1 | IC6 | ISO1541 Low-Power Bidirectional I²C Isolator | 296-34872-1-ND | DigiKey | |
| 4 | IC0-3 | ADS1114 16-Bit I²C Analog-to-Digital Converter | Addresses A0-A3 | 296-24932-1-ND | DigiKey |
| 1 | IC4 | ADS1100 16-Bit I²C Analog-to-Digital Converter | Address A4 (100) | 296-14301-1-ND | DigiKey |
| 1 | IC5 | ADS1100 16-Bit I²C Analog-to-Digital Converter | Address A5 (101) | 296-14302-1-ND | DigiKey |
| 2 | R0,1 | Resistor 1.8kΩ 1/10W ±1% 0603 | I²C Pull-up | 311-1.80KHRCT-ND | DigiKey |
| 8 | C0-7 | Capacitor Ceramic 0.1µF ±10% 25V 0603 | Bypass Capacitors | 490-1524-1-ND | DigiKey |
| 1 | D0 | LED Red Vf=1.8V If=2mA 0603 | 5V Power Indicator | 475-1195-2-ND | DigiKey |
| 1 | R2 | Resistor 1.8kΩ 1/4W ±1% 0603 | P1.8KBYCT-ND | DigiKey | |
| 1 | D1 | LED Yellow Vf=1.8V If=2mA 0603 | VIN Power Indicator | 475-1196-1-ND | DigiKey |
| 1 | R3 | Resistor 15kΩ 1/4W ±1% 0603 | RHM15.0KADCT-ND | DigiKey |