IDPU LVPS

1

• IDPU LVPS
• Critical Design Review
• P. Berg
• University of California - Berkeley

2
Overview

• LVPS Overview
• Requirements
• Specification
• Design
• Mass and Power
• Schedule
• Issues

3
Requirements

• LVPS REQUIREMENTS
• INPUT IS 28 VOLT PROBE POWER (22-34 VOLTS
  NOMINAL)
• PRIMARIES ARE CURRENT LIMITED
• TOPOLOGIES CHOSEN TO PROMOTE EFFICIENCY
• FREQUENCIES TO BE 100 KHZ OR GREATER
• SUPPLIES ARE SOFT STARTED TO MINIMIZE TURN-ON
  STRESSES INPUT CURRENT CONTROLLED
• REGULATION 1 ON DIRECTLY REGULATED VOLTAGES
  AND 5 ON AUXILLARY VOLTAGES
• ISOLATED SECONDARIES WHERE APPROPRIATE
• DIGITAL CONTROL SIGNALS FROM PCB
• ACTEL 2.5V PRECEEDS ACTEL 5V

4
Requirements

• Parts Stress Analysis
• Design meets derating guidelines of GSFC PPL-21
• Temperature Range
• Parts meet Temperature Guidelines
• Operating Temperature range 30C to 45C
• Survival Temperature range 50C to 65C

5
Requirements

• THIRTY TWO OUTPUT VOLTAGES
• 100V EFI
• 10V EFI
• 5V EFI
• 5V EFI
• 2.5V EFI
• 10 Floating in six instances
• 5V SMA
• 2.5V IDPU
• 5V IDPU
• 5 Va IDPU
• - 8 V IDPU
• 10V IDPU
• 28 Regulated for ESA
• Three Headroom Voltages

6
Specifications

• Electro-Mechanical Specifications
• Output Connector to Backplane
• KA80.1/127CPFC10TBH
• HYPERTRONICS 80 PIN 100,000 CYCLES
• Dielectric isolation gt1050VRMS (need 200VDC)
• J100 Location only
• 4 Amp Rating
• Front Panel Input Connector
• DB9P
• ENCLOSURE
• Spacing is one inch
• Dependent upon tallest parts (e.g. magnetics)
• Electrical shield

7
Specifications

• Connector Dimensions (LVPS Interface)

8
Design
9
Design
10
Design
11
Design

• Design Considerations
• Digital and Analog Signal Separation
• Voltage Capabilities
• Worst Case Floating Voltages /-100V
• Isolation gt1050VAC
• Current Capabilities
• Worst Case Current Req Actuators _at_ 2A
• Pin Capabilities 4A

12
Design

• PWM REGULATOR

13
Design
DUAL ? FLOATING SUPPLY
14
Design
PINOUT
15
Mass Power

• Power Dissipation
• FOR 12.71 DELIVERED _at_65 OVERALL EFFICIENCY
  DISSIPATION IS 4.49W
• Mass
• 430 Grams CBE (BOARD ONLY)

16
SCHEDULE
17
Issues

• SCHEDULE-LAYOUT BY MID MAY, HARDWARE BY MID JUNE

• PARTS CANDIDATES
• UC1526A PWM PASSED RADIATION
• LM5030 PWM - FAILED RADIATION
• LTC1877 PWM FAILED RADIATION