SBAS910A
June 2018 – July 2019
AFE4420
PRODUCTION DATA.
1
Features
2
Applications
3
Description
Device Images
Simplified Schematic
4
Revision History
5
Device and Documentation Support
5.1
Receiving Notification of Documentation Updates
5.2
Community Resources
5.3
Trademarks
5.4
Electrostatic Discharge Caution
5.5
Glossary
6
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
YZ|30
Thermal pad, mechanical data (Package|Pins)
Orderable Information
sbas910a_oa
1
Features
Supports signal acquisition of up to 16 phases
Flexible allocation of LEDs and PDs in each phase
Accurate, continuous heart-rate monitoring:
Up to 100-dB dynamic range
Low current for continuous operation on a wearable device with a typical value
15 μA for an LED, 20 μA for the receiver
Transmitter:
Supports common anode LED configuration
8-Bit programmable LED current with range adjustable from 50 mA to 200 mA
Mode to fire two LEDs in parallel
Programmable LED on-time
Simultaneous support of 4 LEDs for optimized SpO2, HRM, or multi-wavelength HRM
Programmable control signals to extend operation to 8 LEDs using external SPDT switches
Receiver:
Supports 4 time-multiplexed photodiode inputs
Individual DC offset subtraction DAC at TIA input for each LED, ambient with 7-bit control and range up to ±254 µA
Transimpedance gain: 10 kΩ to 2 MΩ
Digital ambient subtraction at ADC output to suppress ambient tones
Noise filtering with programmable bandwidth
Supports external clock and internal oscillator modes
Automatic ambient cancellation mode (AACM) to increase receiver dynamic range
Two programmable GPIO pins with flexible interrupt generation
FIFO with 128-sample depth
I
2
C, SPI interfaces: selectable by pin
Operating temperature range: –40°C to +85°C
2.6-mm × 2.1-mm DSBGA, 0.4-mm pitch
Supplies:
Rx:
1.7 V to 1.9 V (LDO bypass)
1.9 V to 3.6 V (LDO enabled)
Tx: 3 V to 5.5 V
IO: 1.7 V to RX_SUP