1. Optical Heart Monitor / Jump Drive Group 6 Sponsor: Calit2 Mentor: Paul Blair, Ph.D. Team: Kari Nip, Matt Chandrangsu, Jeffrey Chi

2. Agenda Design Specifications Weekly Progress Gantt Chart Questions

3. Pulse Oximeter Typically a 2 LED system One red LED (660nm wavelength), one infared LED (910nm). Absorption of these wavelengths is different in oxyhemoglobin and deoxygenated hemoglobin. We only use 1 LED Only care about heart rate, not oxygenation levels. Still use a 2 LED device, as it is more readily available

4. ADC Specs 10 Bit resolution 65-260 µs Conversion Time Up to 15 ksps at Maximum Resolution Through Nyquist theory, the maximum signal input frequency is 7.5 kHz Input heart beat signal (approx. 60 Hz) Previous data found at 250 sps

5. HR Circuitry: OpAmp Specifications LM358 chip – has two independent operational amplifiers on it 100dB voltage gain 3V – 32V supply voltage range 2mV input offset voltage 1MHz bandwidth

6. HR Circuitry: Sensor light

7. HR Circuitry Received a commercial heart rate monitor PCB to investigate Compared PSPICE simulations to circuit data Familiarized with Eagle Layout editor

8. HR Circuitry: PSPICE Simulation

9. HR Circuitry: Circuit data

10. HR Circuitry: Simulation vs. lab At the maximum points of both output and input signal: Voltage gain (simulated) = 13.655 Voltage gain (circuit) = 9.337

11. HR Circuitry: Eagle layout

12. HR Circuitry: Plans Continue working with Eagle Layout editor Refine PCB layout Better component placement Shorter traces Use of vias to make PCB layout more concise

13. Signal Filtering Input Signal and Matched Filter

14. Signal Filtering Convolution of matched filter (f) and input signal (g)

15. Signal Filtering: Plans Make filtered function square wave signal Develop further understanding of Matlab functions Create filtering program in C

16. File Allocation Table 0-10 File name (8 bytes) with extension (3 bytes) 11 Attribute - a bitvector. Bit 0: read only. Bit 1: hidden. Bit 2: system file. Bit 3: volume label. Bit 4: subdirectory. Bit 5: archive. Bits 6-7: unused. 12-21 Reserved (see below) 22-23 Time (5/6/5 bits, for hour/minutes/doubleseconds) 24-25 Date (7/4/5 bits, for year-since-1980/month/day) 26-27 Starting cluster (0 for an empty file) 28-31 Filesize in bytes

17. Interfacing with USB Completed code to control LED’s on development board with button presses. Currently researching USB storage code to find which functions to leverage. Upcoming Tasks: First: Going to merge LED control code with storage code. Second: Implement button press controlled file modification

18. Gantt Chart