Payload ICD

Introduction

Each subsystem should have an interface control document (ICD). Detail the mechanical, electrical, data, thermal interfaces between this subsystem and other subsystems (what's unique to this project).

Electrical Interface

• PLD receives power from a distributed power bus at unregulated battery voltage (Vbat = 6.4 +/- 0.4V) through distribution load switches that are operated by the Power module controller. 

• Power ON/OFF is controlled by a CAN-Controlled Load Switches and Monitors (CCLSM).

Mechanical Interface

• M3 or M4 fasteners with hex drive: Used for assembly throughout the shell

• 1x hinge: located between the payload reflector and the structure shell

• 1x hinge: located between the payload feed and the structure shell

Data Interface

• Power ON/OFF is controlled by a CAN-Controlled Load Switches and Monitors (CCLSM) through the auxiliary CAN bus, which is commanded and controlled by the Power subsystem

• 2 CAN Bus connections: 1 for PWR and 1 for PLD

  • Data rate: 250 kbps

• 3 analog connection for thermistor.

• 1 2.92-SMA connection to the antenna.

Thermal Interface

• 3 thermistor to measure temperatures at different parts of the PLD 

  • 1 for the noise source

  • 1 for the radiometer RF stage

  • 1 for the ambient temperature of the PLD unit

• Operational temperature range: -40°C to 85°C. 

• Survival temperature range: -40°C to 85°C. 

• The PLD subsystem provides ambient PLD temperature reading to the CDH over CAN

Software Interface