SLAAE25 May   2021 MSP430FR2355 , MSP430FR2355

 

  1.   Trademarks
  2. 1Introduction
  3. 2Theory of Operation
  4. 3Single-Chip Design
  5. 4Hardware
  6. 5Software
    1. 5.1 Sample and Condition the PIN Diode Signal
    2. 5.2 Sample and Measurement Sequence
    3. 5.3 First Stage DC Tracking
    4. 5.4 Low-Pass FIR Filter
    5. 5.5 Calculate Heart and SpO2
  7. 6Debug GUI
  8. 7Test Result
  9. 8Summary
  10. 9References

Single-Chip Design

Figure 3-1 shows the proposed block diagram of a single-chip pulse oximeter design using the MSP430FR235x. All four SACs are utilized optimally: two for the LED drive stage (Red and IR) and two for the photodiode signal conditioning (TIA and gain stage). Internal clocks and voltage references are selected to minimize the use of external components thus reducing the overall Bill of Material (BOM) cost as well as the footprint of the design.

GUID-36BEA12C-F545-4341-9CCC-45FCB4703241-low.png Figure 3-1 Single-Chip Solution for Pulse Oximeter