EVALUATION KIT AVAILABLE Click here for production status of specific part numbers. MAXM86161 Single-Supply Integrated Optical Module for HR and SpO Measurement 2 General Description Benefits and Features The MAXM86161 is an ultra-low-power, completely inte- Complete Single-Channel Optical Data Acquisition grated, optical data-acquisition system. On the transmitter System side, the MAXM86161 has three programmable high- Built-In Algorithm Further Enhances Rejection of Fast current LED drivers. On the receiver side, MAXM86161 Ambient Transients consists of a high efficiency PIN photo-diode and an opti- Optimized Architecture for Reflective Heart Rate and cal readout channel. The optical readout has a low-noise SpO Monitoring 2 signal conditioning analog front-end (AFE), including Low Dark Current Noise of < 50pA RMS (Sample-to- 19-bit ADC, an industry-lead ambient light cancellation (ALC) circuit, and a picket fence detect and replace Sample Variance) algorithm. Due to the low power consumption, compact Lower Effective Dark Current Noise Achievable size, easy, flexible-to-use, and industry lead ambient light through Multiple Sample Modes and On-Chip rejection capability of the MAXM86161, the device is ideal Averaging for a wide variety of optical sensing applications such as High-Resolution 19-bit Charge Integrating ADC heart rate detection and pulse oximetry. Three Low-Noise 8-Bit LED Current DACs The MAXM86161 operates on a 3.0V to 5.5V V LED Excellent Dynamic Range > 89dB in White Card single supply voltage. It supports a standard compatible Loop-Back Test (Sample-to-Sample Variance) interface and fully autonomous operation. Each device has a large 128-word built-in FIFO. The MAXM86161 is Excellent Ambient Range and Rejection Capability available in compact 2.9mm x 4.3mm x 1.4mm, 14-pin > 100A Ambient Photodetector Current OLGA package. > 70dB Ambient Rejection at 120Hz Ultra-Low-Power Operation for Wearable Devices Applications Low-Power Operation, Optical Readout Channel Optimized for In-Ear Applications < 10A, Typical at 25sps Miniature Package for Mobile Applications Short Exposure Integration Period of 14.8s, 29.4s, 58.7s, 117.3s Optimized Performance to Detect: Low Shutdown Current = 1.6A (typ) Optical Heart Rate Oxygen Saturation (SpO ) Miniature 2.9mm x 4.3mm x 1.4mm, 14-pin OLGA 2 Continuous Monitoring for HRV Package -40C to +85C Operating Temperature Range Ordering Information appears at end of data sheet. 19-100523 Rev 0 3/19MAXM86161 Single-Supply Integrated Optical Module for HR and SpO Measurement 2 TABLE OF CONTENTS General Description ............................................................................ 1 Applications .................................................................................. 1 Benefits and Features .......................................................................... 1 Simplified Block Diagram........................................................................ 5 Absolute Maximum Ratings ...................................................................... 6 Package Information ........................................................................... 6 Electrical Characteristics ........................................................................ 6 Typical Operating Characteristics .................................................................11 Pin Configuration ............................................................................. 13 Pin Description ............................................................................... 13 Detailed Description........................................................................... 14 Optical Subsystem 14 LED Driver . 14 FIFO Configuration 14 LED Sequence Control (0x20 to 0x22) 14 Pseudo-Code Example of Initialize the Optical AFE 20 Pseudo-Code for Interrupt Handling with FIFO A FULL 21 Pseudo-Code Example of Reading Data from FIFO 21 Optical Timing 22 One LED Pulsing with No Direct Ambient Sampling 22 One LED Pulsing with Direct Ambient Sampling . 23 Two LEDs Pulsing Sequentially with Direct Ambient Sampling . 23 All LEDs Pulsing Sequentially with Direct Ambient Sampling . 24 ADC Architecture and Transfer Function Non-Linearity (XNL) Trim 24 Proximity Mode Function . 25 Picket Fence Detect-and-Replace Function . 26 Layout Guidelines . 29 2 I C/SMBus Compatible Serial Interface 30 2 Detailed I C Timing Diagram 30 Bit Transfer 30 START and STOP Conditions . 30 Early STOP Conditions 30 Slave Address . 30 Acknowledge Bit . 31 2 I C Write Data Format . 32 2 I C Read Data Format . 33 Maxim Integrated 2 www.maximintegrated.com