Datasheet

Detailed Description
The MAX30101 is a complete pulse oximetry and heart-
rate sensor system solution module designed for the
demanding requirements of wearable devices. The
MAX30101 maintains a very small solution size without
sacrificing optical or electrical performance. Minimal
external hardware components are required for integra-
tion into a wearable system.
The MAX30101 is fully adjustable through software regis-
ters, and the digital output data can be stored in a 32-deep
FIFO within the IC. The FIFO allows the MAX30101 to be
connected to a microcontroller or processor on a shared
bus, where the data is not being read continuously from
the MAX30101’s registers.
SpO
2
Subsystem
The SpO
2
subsystem contains ambient light cancellation
(ALC), a continuous-time sigma-delta ADC, and propri-
etary discrete time filter. The ALC has an internal Track/
Hold circuit to cancel ambient light and increase the effec-
tive dynamic range. The SpO
2
ADC has a programmable
full-scale ranges from 2µA to 16µA. The ALC can cancel
up to 200µA of ambient current.
The internal ADC is a continuous time oversampling
sigma-delta converter with 18-bit resolution. The ADC
sampling rate is 10.24MHz. The ADC output data rate
can be programmed from 50sps (samples per second) to
3200sps.
Temperature Sensor
The MAX30101 has an on-chip temperature sensor for
calibrating the temperature dependence of the SpO
2
subsystem. The temperature sensor has an inherent
resolution 0.0625°C.
The device output data is relatively insensitive to the
wavelength of the IR LED, where the red LED’s wave-
length is critical to correct interpretation of the data. An
SpO
2
algorithm used with the MAX30101 output signal
can compensate for the associated SpO
2
error with ambient
temperature changes.
LED Driver
The MAX30101 integrates red, green, and IR LED drivers
to modulate LED pulses for SpO
2
and HR measurements.
The LED current can be programmed from 0 to 50mA
with proper supply voltage. The LED pulse width can be
programmed from 69µs to 411µs to allow the algorithm to
optimize SpO
2
and HR accuracy and power consumption
based on use cases.
880nm660nm
ADC
AMBIENT LIGHT
CANCELLATION
ANALOG
ADC
DIE TEMP
OSCILLATOR
DIGITAL
FILTER
DIGITAL
DATA
REGISTER
LED DRIVERS
I
2
C
COMMUNICATION
INT
SDA
SCL
V
DD
V
LED+
N.C.N.C.
GND
PGND
RED IR
VISIBLE+IR
MAX30101
GREEN
527nm
N.C.
www.maximintegrated.com
Maxim Integrated │ 10
MAX30101 High-Sensitivity Pulse Oximeter and
Heart-Rate Sensor for Wearable Health
Functional Diagram