Project Ownership: Ravi Shah

Github Link: https://github.com/lhr-solar/DataAcq-EnvironmentBoard

BOM Link: WIP

Description/Purpose

• Measure environmental data throughout the car, including humidity, airflow, and temperature (see data acquisition SRR for more rationale)

• Physical: Make it as small as possible (need input from mechanical/E-mech)

  • Discuss form factor and mounting with Cooling

• Interface: this board will send all environment data to the main Environment Leader board via internal Data Acq. Environment CAN

  • Will then be sent over TelemetryCAN to the telemetry module??

• Modularity: Pick and choose which sensors to use on each board during assembly – should not require all sensors to be present

Context

Location of the board: Several boards will be located throughout the car (specifically?)

List of I/O and connections: TODO

• #, Name, Type, Ideal Voltage, Notes, etc.

Main

Schematic (WIP)

Basic sensor implementation as below

List of Circuit Components

Humidity Sensor – https://sensirion.com/products/catalog/SHT45

• Description: Digital relative humidity and temperature sensor

• Justification for selection of specific part: ??

• Datasheet link: https://sensirion.com/media/documents/33FD6951/662A593A/HT_DS_Datasheet_SHT4x.pdf

• Associated passives/components:

  • 100nF capacitor

  • 2x 10k resistors

• Interface: I2C

• Notes:

  • 3.3v supply voltage

  • Maximal power-up time = 1ms

  • Also measures temperature – not using this functionality due to modular nature of board

  • Accurate to ±1.0 %RH

Airflow Sensor – FS3000

• Description: Air velocity sensor module with 12-bit digital output

• Justification for selection of specific part: ??

• Datasheet link: https://www.mouser.com/datasheet/2/698/REN_FS3000_DST_20230207-3075780.pdf

• Associated passives/components:

  • 3x 0.1uF capacitors

  • 1uF capacitor

• Interface: I2C

• Notes:

  • 3.3v supply voltage

Temperature Sensor – https://www.ti.com/product/LMT87

• Description: Analog temperature sensor with Class-AB output

• Justification for selection of specific part: ??

• Datasheet link: https://www.ti.com/lit/ds/symlink/lmt87.pdf?ts=1728144032765&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FLMT87

• Associated passives/components:

  • 0.01uF capacitor connected between Pin 4 (VDD) and GND, other VDD pins connect to power plane

• Interface:

  • Analog - output voltage inversely proportional to temperature as shown below

  • 

• Notes:

  • 2.7v to 5.5v supply voltage

  • 0.7ms power-on time

CAN IC (WIP)

Need input on chip to use

• Description:

• Justification:

• Datasheet link:

• Associated passives/components:

• Interface:

• Notes:

12v to 3.3v step-down (WIP)

Need input on converter

• Description:

• Justification:

• Datasheet link:

• Associated passives/components:

• Interface:

• Notes:

Connectors (WIP)

• PSOM

  • Power - Need input about power architecture

  • GND

  • Anything else needed??

• EnvironmentCAN

  • TODO

Layout (WIP)

Dimensions:

Requirements/Constraints: TODO (From mech/emech/cooling)

Design Choices (WIP)

PCB (WIP)

3D Model (WIP)

Additional Considerations…