1. Michael Davies Andrew Mountain Dan Hoang Daniel Brink Michael Davies Andrew Mountain Dan Hoang Daniel Brink Power Distribution Control Unit

2. Functionality Power Distribution Control Unit for Colorado Space Grant’s Satellite Citizen Explorer Implement commands from the satellite’s flight computer to provide the desired power to the unit’s subsystems Monitor specified temperatures and power buses

3. Schematic

4. 17 – 4-Pin solid state relays Control using 5V logic Direct I/O with PIC Connected with desired voltage Distribution of Power

5. Schematic

6. Voltage Divider Maximum range voltage – low power consumption Analog multiplexer A/D converter on chip Temperature

7. Schematic

8. Power Supplies Rigorously test power supplies Power draw on each bus Concern with noise on 5V power bus –Pi-Filter near each chip that require 5V

9. PCB Board 4-Layer Board 2 Parallel 7.15" X 7.65" boards Through hole parts for stability 7.15" X 7.65"

10. Parts List Microcontroller: PIC 16C77 Relays: DMO063 Clock: ACH-20.000MHz Thermistor: YSI44901 12v to 15v/-15v Converter: JR12D15-330 12v to 24v Boost Converter: SI12S24-1250 12v to 5v Converter: LANC1205W5S Flight Computer Interface: RS485/422 Max3082ESH PC Interface: Max208CN6

11. Microcontroller

12. Relays

13. Thermistors

14. Flight Computer Interface Serial Communication

15. PC Interface

16. Basic Software Functions INITIALIZE VOLTAGES CURRENTS TEMPS DELAY SEND INFO?

17. Basic Software Functions VOLTAGES SET ANALOG SWITCH POS 1 A/D CONVERSION SAVE VOLTAGE 1 SET ANALOG SWITCH POS 2 SAVE VOLTAGE 2 SET ANALOG SWITCH POS n SAVE VOLTAGE n RETURN

18. Basic Software Functions INTERRUPT RECEIVE TRANSMIT OTHER? RETURN

19. Basic Software Functions RECEIVE SET RELAYSSEND INFO RETURN READ BYTE

20. BOOT SEQUENCE CD&H 1 min delay ADCS 3-5 sec delay Mnet 3-5 sec delay Science 3-5 sec delay Deploy REQUIRED -extra delay for FC ARBITRARY Basic Software Functions

21. Schedule

22. Division of Labor Michael Davies: Software Andrew Mountain: PCB/Schematic Design Daniel Brink: Hardware layout Dan Hoang: Hardware/Software interfacing

23. Milestones Milestone 1: Completed Prototype (wire wrap) and interface-able test code Milestone 2: Completed PCB Design and ready to order (first revision) Design Expo