Built-In Test Software for Deformable Mirror High Voltage Drivers Built-In Test Software for Deformable Mirror High Voltage Drivers Jianwei Zhou Home Institution: University of Hawaii at Manoa CfAO Akaimai Internship 2008 Subaru Telescope Mentor: Stephen Colley Funding provided by the Center for Adaptive Optics through its National Science Foundation Science and Technology Center grant (#AST )

Todays Presentation Background Background Importance of Build-In Test software Importance of Build-In Test software Design Process Design Process Conclusion Conclusion Acknowledgement Acknowledgement

Acronyms A/D – Analog to Digital A/D – Analog to Digital D/A – Digital to Analog D/A – Digital to Analog BIT- Built-In Test BIT- Built-In Test DM- Deformable Mirror DM- Deformable Mirror HV – High Voltage HV – High Voltage ICD – In-Circuit Debugger ICD – In-Circuit Debugger LGSAO – Laser Guide Star Adaptive-Optics LGSAO – Laser Guide Star Adaptive-Optics MUX – Multiplexer MUX – Multiplexer

Project Overview Design Built-In Test (BIT) software for deformable mirror high voltage driver in the Subaru LGSAO system. Design Built-In Test (BIT) software for deformable mirror high voltage driver in the Subaru LGSAO system. Measurements performed by BIT circuitry Input Voltages Input Voltages Output Voltages Output Voltages Power Supply Voltages Power Supply Voltages Board Temperature Board Temperature

Deformable Mirror (DM) DM is used with wavefront sensor to provided optical control and correction. DM is used with wavefront sensor to provided optical control and correction. The DM is divided into 188 segments with separate control voltage to each segment The DM is divided into 188 segments with separate control voltage to each segment DM operates with maximum voltages of +400V, and HV amplifiers with gain of 40 are used to amplify input voltages of + 10v to +400v. DM operates with maximum voltages of +400V, and HV amplifiers with gain of 40 are used to amplify input voltages of + 10v to +400v.

HV Driver Subsystem The HV driver subsystem in the Subaru LGSAO system consist of 10 HV Amplifier boards The HV driver subsystem in the Subaru LGSAO system consist of 10 HV Amplifier boards

High Voltage Amplifier Board High Voltage Amplifier Board

Real-Time Control Computer D/A Converter Board HV Amplifier Board w/BIT DM v v Digital Data Importance of Built-In Test Software Importance of Built-In Test Software

Built-In Test Circuit Main components: Analog Multiplexer (Mux) Analog Multiplexer (Mux) Analog-To-Digital Converter Analog-To-Digital Converter Microcontroller (PIC 16F877) Microcontroller (PIC 16F877) Temperature Sensor Temperature Sensor Mux A/D Converter Microcontroller Temperature Sensor Host Computer BIT Circuit

Built-In Test Software Program Language use: C Program Language use: C Step 1: Program in C Step 1: Program in C Step 2: Compile to Assembly language by PICC STD. Step 2: Compile to Assembly language by PICC STD. Pros and cons C is easier and much shorter than assembly language C is easier and much shorter than assembly language Programming requires the knowledge of microcontroller Programming requires the knowledge of microcontroller

In-Circuit Debugger Real-time debugger and programmer Real-time debugger and programmer

MPLAB IDE

Memory Constraints of Microcontroller Programs must fit in the available on-chip program memory ( very small compare to computer) Programs must fit in the available on-chip program memory ( very small compare to computer) Must optimize the code to reduce the memory Must optimize the code to reduce the memory

Conclusion Tested the BIT circuit Tested the BIT circuit 1 bad A/D converter is found in one board 1 bad A/D converter is found in one board Fabrication error of temperature sensor Fabrication error of temperature sensor BIT software successfully measures the input voltages, output voltages, and power supply voltages on a HV amplifier board BIT software successfully measures the input voltages, output voltages, and power supply voltages on a HV amplifier board

Work To Be Completed Communication between the BIT circuit and host computer Communication between the BIT circuit and host computer Run the BIT software in the whole LGSAO system Run the BIT software in the whole LGSAO system

Personal Thought A valuable opportunity to learn about circuit design A valuable opportunity to learn about circuit design Application of the knowledge learnt in school to real life practice Application of the knowledge learnt in school to real life practice Increased research ability Increased research ability Increased Confidence Increased Confidence

Acknowledgements Stephen Colley, Mentor Stephen Colley, Mentor Akamai Internship staff Akamai Internship staff Sarah Anderson, Hawaii Island Internship Coordinator Sarah Anderson, Hawaii Island Internship Coordinator Lynne Raschke, Science Communication Lead Instructor Lynne Raschke, Science Communication Lead Instructor Scott Seagroves, Science Communication Co-instructor Scott Seagroves, Science Communication Co-instructor Lisa Hunter, Akamai Internship Director Lisa Hunter, Akamai Internship Director