EVALUATION KIT AVAILABLE
Click here for production status of specific part numbers.
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
General Description
The MAX86150 is an integrated electrocardiogram, pulse
oximeter, heart rate monitor sensor module. It includes
internal LEDs, photodetector, and low-noise electronics
with ambient light rejection. The MAX86150 helps ease
design-in to mobile and wearable devices.
The MAX86150 operates on a 1.8V supply voltage
with a separate power supply for the internal LEDs.
Communication to and from the module is entirely through
a standard I2C-compatible interface. The module can be
shut down through software with near zero standby current,
allowing the power rails to remain powered at all times.
Applications
Benefits and Features
●● Electrocardiogram (ECG) Optimized for Dry
Electrode Operation
●● Reflective Heart Rate Monitor and Medical-Grade
Pulse Oximeter
●● Miniature 3.3mm x 5.6mm x 1.3mm 22-pin Optical
Module
• Optical-Grade Glass for Long-Term Optimal and
Robust Performance
●● Ultra-Low Power Operation for Mobile Devices
• Ultra-Low Shutdown Current (0.7μA Typical)
●● High SNR and Robust Ambient Light Cancellation
●● -40°C to +85°C Operating Temperature Range
●● Smartphones
●● Tablets
●● Wearable Devices
Ordering Information appears at end of data sheet.
●● Fitness Assistant Devices
Simplified Block Diagram
HOST (AP)
OPTICAL
ELECTRICAL
APPLICATIONS
DIGITAL NOISE
CANCELLATION
HARDWARE
FRAMEWORK
LED
DRIVERS
ALGORITHMS
DRIVER
I2C
DATA FIFO
19-BIT ADC
HUMAN
FINGER
RED/IR LEDS
PHOTODIODE
GLASS LID
AMBIENT LIGHT
CANCELLATION
18-BIT ADC
AMBIENT
LIGHT
AFE
PACKAGING
ELECTRODES
MAX86150
19-8402; Rev 2; 12/18
LEFT
HAND
RIGHT
HAND
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
TABLE OF CONTENTS
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Benefits and Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Simplified Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Electrical Characteristics (continued) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical Characteristics (continued) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Electrical Characteristics (continued) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Photoplethysmogram (PPG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Photoplethysmogram (PPG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Electrocardiogram (ECG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Functional Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
SpO2 Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
LED Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Proximity Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Electrocardiogram (ECG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
ECG and PPG Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Register Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Interrupt Status 1 (0x00) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Interrupt Status 2 (0x01) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Interrupt Enable 1 (0x02) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Interrupt Enable 2 (0x03) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
FIFO Write Pointer (0x04) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Overflow Counter (0x05) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
FIFO Read Pointer (0x06) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
FIFO Data Register (0x07) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
FIFO Configuration (0x08) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
FIFO Data Control Register 1 (0x09) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
FIFO Data Control Register 2 (0x0A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
System Control (0x0D) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
PPG Configuration 1 (0x0E) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
www.maximintegrated.com
Maxim Integrated │ 2
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
TABLE OF CONTENTS (CONTINUED)
PPG Configuration 2 (0x0F) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Prox Interrupt Threshold (0x10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
LED2 PA (0x12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
LED Range (0x14) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
ECG Configuration 1 (0x3C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
ECG Configuration 3 (0x3E) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Part ID (0xFF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Power Sequencing and Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Power-Up Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Power-Down Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
I2C Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Bit Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
START and STOP Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Early STOP Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Slave Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Write Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Read Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
FIFO Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
FIFO Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
FIFO Data Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
FIFO Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
FIFO Flush . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
FIFO Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Typical Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
www.maximintegrated.com
Maxim Integrated │ 3
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
LIST OF FIGURES
Figure 1. I2C-Compatible Interface Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 2. MAX86150 ECG Subsystem Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 3. Power-Up Sequence of the Power Supply Rails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 4. START, STOP, and REPEATED START Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Figure 5. I2C Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Figure 6. Writing One Data Byte to MAX86150 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Figure 7. Reading One Byte of Data from MAX86150 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Figure 8. Reading Multiple Bytes of Data from the MAX86150 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Figure 9. Example of FIFO Organization with Four Active Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Figure 10. Example of FIFO Organization with Two Active Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
LIST OF TABLES
Table 1. FIFO Data Control registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 2. FDx Format Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 3. FIFO Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Table 4. Sample of FIFO Data Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 5. FIFO Handling Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 6. FIFO Sample Elements Order with four active elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 7. FIFO Sample Elements Order with two active elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
www.maximintegrated.com
Maxim Integrated │ 4
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Absolute Maximum Ratings
VDD_ANA to GND_ANA.........................................-0.3V to +2.2V
VDD_DIG to GND DIG...........................................-0.3V to +2.2V
VDD_ANA to VDD_DIG...................................... VDD_DIG - 0.3V to
VDD_DIG + 0.3V
GND_ANA to GND_DIG................................ GND_DIG - 0.3V to
GND_DIG + 0.3V
PGND to GND_ANA..............................................-0.3V to +0.3V
VLED to PGND......................................................-0.3V to +6.0V
ECG_P, ECG_N, ECG_C to GND_ANA...............-0.3V to +2.2V
C1_P, C1_N to GND_ANA....................................-0.3V to +2.2V
IDRV_P, IDRV_N to GND_ANA............................-0.3V to +2.2V
VREF to GND_ANA...............................................-0.3V to +2.2V
Output Short-Circuit Duration.....................................Continuous
Continuous Input Current Into Any Pin..............................±20mA
SDA, SCL, INTB to GND_ANA.............................-0.3V to +6.0V
OESIP (derate 5.5mW/°C above +70°C) ..............-40°C to 85°C
Operating Temperature Range............................ -40°C to +85°C
Junction Temperature.......................................................+150°C
Storage Temperature Range............................. -40°C to +105°C
Soldering Temperature (reflow)........................................+260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Package Information
PACKAGE TYPE: 22 OLGA
Package Code
F223A5+1
Outline Number
21-100071
Land Pattern Number
90-100024
THERMAL RESISTANCE, FOUR LAYER BOARD:
Junction-to-Ambient (θJA)
180°C/W
Junction-to-Case Thermal Resistance (θJC)
150°C/W
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”,
“#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing
pertains to the package regardless of RoHS status.
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board.
For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
www.maximintegrated.com
Maxim Integrated │ 5
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Electrical Characteristics
(VDD_ANA = VDD_DIG = 1.8V, VLED = 3.3V, VGND_ANA = VGND_DIG = VPGND = 0V, TA = +25°C, min/max are from TA = -40°C to
+85°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Power Supply Voltage
VDD
Guaranteed by RED and IR count tolerance
1.7
1.8
2.0
V
LED Supply Voltage
VLED
Guaranteed by PSRR of LED driver
3.1
3.3
5
V
Heart rate/SpO2 mode; PPG_LED_PW =
50μs; PPG_SR = 100sps; LED driver = 0mA
400
750
Heart rate/SpO2 mode; PPG_LED_PW =
50μs; PPG_SR = 10sps; LED driver = 0mA
400
ECG sample rate = 200Hz
340
750
Heart rate mode; PPG_LED_PW = 50μs;
PPG_SR = 100sps, LED driver = 0mA
0.03
1
Heart rate mode; PPG_LED_PW = 50μs;
PPG_SR = 100sps, LED driver = 50mA
350
Heart rate mode; PPG_LED_PW = 50μs;
PPG_SR = 10sps, LED driver = 50mA
50
ILED
SpO2 mode; PPG_LED_PW = 50μs;
PPG_SR = 100sps, LED driver = 50mA
750
ILED
SpO2 mode; PPG_LED_PW = 50μs;
PPG_SR = 10sps; LED driver = 50mA
80
ISHDN
TA = +25°C
0.5
12
μA
ISHDNVLED
TA = +25°C
0
1
μA
1.204
1.215
V
POWER SUPPLY
VDD Supply Current
IDD
ILED
VLED Supply Current
VDD Current in Shutdown
VLED Current in
Shutdown
Reference Voltage
(Note 2)
VREF
Bypass to GND_ANA with 1µF
1.192
μA
μA
PULSE OXIMETRY/HEART RATE SENSOR CHARACTERISTICS
ADC Resolution
19
bits
RED_C
Proprietary ATE setup, LED2_PA = 0x16,
PPG_LED_PW = 50μS, PPG_SR =
100sps, TA = +25°C
120,072
140,072
160,072
Counts
IR ADC Count (Note 3)
IR_C
Proprietary ATE setup, LED1_PA = 0x16,
PPG_LED_PW = 50μS, PPG_SR =
100sps, TA = +25°C
136,072
156,072
176,072
Counts
Dark Current Counts
DC_C
ALC = ON, LED2_PA = LED1_PA = 0x00,
PPG_LED_PW = 50μS, PPG_SR = 100sps,
PPG_ADC_RGE[1:0] = 8μA, TA = +25°C
0.0004
0.01
% of FS
0.05
0.5
% of FS
0.05
0.5
% of FS
9.8304
10.027
MHz
Red ADC Count (Note 3)
RED/IR ADC Count PSRR (VDD)
PSRR_VDD
Propriety ATE setup, 1.7V < VDD < 2.0V,
LED1_PA = 0x16, LED2_PA = 0x16,
PPG_LED_PW = 50μS, PPG_SR =
100sps, TA = +25°C
RED/IR ADC Count—
PSRR (LED Driver
Outputs)
PSRR_LED
Propriety ATE setup, 3.1V < VLED < 5V, LED1_
PA = 0x16, LED2_PA = 0x16, PPG_LED_PW
= 50μS, PPG_SR = 100sps, TA = +25ºC
ADC Clock Frequency
CLK
www.maximintegrated.com
9.633
Maxim Integrated │ 6
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Electrical Characteristics (continued)
(VDD_ANA = VDD_DIG = 1.8V, VLED = 3.3V, VGND_ANA = VGND_DIG = VPGND = 0V, TA = +25°C, min/max are from TA = -40°C to
+85°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
870
880
900
nm
650
660
670
nm
IR LED (LED1) CHARACTERISTICS (Note 4)
LED Peak Wavelength
λP
ILED = 20mA, TA = +25°C
RED LED (LED2) CHARACTERISTICS (Note 4)
LED Peak Wavelength
λP
ILED = 20mA, TA = +25°C
LED DRIVERS
LED Current Resolution
LED Drive Current
ILED
8
bits
LEDx_RGE = 0x0
50
mA
LEDx_RGE = 0x1
100
ECG (Note 5)
ADC Resolution
Gain
18
G
VIN = ±10mVDC, TA = +25°C, VDIFF = 0mV
(Note 6)
Gain Error
VIN = 20mVP-P,AC ±400mVDC, IA_GAIN =
9.5, PGA_GAIN = 8, f = 84Hz, TA = +25°C
DC Differential Input
Range
VIN = 20mVP-P,AC, f = 84Hz, gain error <
2.2%, TA = +25°C
CMRR
72
76
-400
bits
80
V/V
2.2
%
+400
mV
Balanced Inputs, 60Hz with ±300mV
differential DC offset, per AAMI/IEC
standard, lead biasing enabled
136
dB
51kΩ // 47nF imbalance, 60Hz with ±300mV
differential DC offset, per AAMI/IEC
standard, lead biasing enabled
78
dB
dB
DC CMRR
Gain = 76V/V, input pins tied together
(no electrodes), 0.2V < VIN < 1.0V
80
120
DC PSRR
Gain = 76V/V, input pins tied together
(no electrodes), 1.7V < VDD < 2.0V
70
100
AC PSRR
ECG_P/N tied together, AC signal at 60Hz,
10mVP-P to VDD, lead bias disabled
95
dB
Input Impedance
ECG_P or ECG_N to GND_ANA, DC,
lead biasing enabled
100
MΩ
Input Referred Noise
Gain = 76V/V, inputs tied together on chip,
ECG sample rate = 400sps (Register 0x3C
= 0x02), 0.5Hz to 100Hz
0.76
μVRMS
www.maximintegrated.com
Maxim Integrated │ 7
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Electrical Characteristics (continued)
(VDD_ANA = VDD_DIG = 1.8V, VLED = 3.3V, VGND_ANA = VGND_DIG = VPGND = 0V, TA = +25°C, min/max are from TA = -40°C to
+85°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.4
V
0.4
V
DIGITAL CHARACTERISTICS (SDA, SCL, INTB)
Output Low Voltage
SDA, INTB
VOL
ISINK = 6mA
I2C Input Voltage Low
VIL_I2C
SDA, SCL
I2C Input Voltage High
VIH_I2C
SDA, SCL
Input Hysteresis (Note 3)
VHYS
SDA, SCL
200
mV
Input Capacitance (Note 3)
CIN
SDA, SCL
10
pF
Input Leakage Current
IIN
1.4
V
VIN = 0V, TA = +25°C (SDA, SCL)
0.01
1
VIN = VDD, TA = +25°C (SDA, SCL)
0.01
1
μA
I2C TIMING CHARACTERISTICS (SDA, SCL) (Note 4, Figure 1)
I2C Write Address
BC
Hex
I2C
BD
Hex
Read Address
Serial Clock Frequency
fSCL
0
Bus Free Time Between
STOP and START
Conditions
400
kHz
tBUF
1.3
µs
Hold Time (Repeated)
START Condition
tHD,STA
0.6
µs
SCL Pulse-Width Low
tLOW
1.3
µs
SCL Pulse-Width High
tHIGH
0.6
µs
Setup Time for a Repeated
START Condition
tSU,STA
0.6
µs
Data Hold Time
tHD,DAT
0
Data Setup Time
tSU,DAT
100
ns
Setup Time for STOP
Condition
tSU,STO
0.6
µs
Pulse Width of
Suppressed Spike
tSP
0
Bus Capacitance
CB
SDA and SCL Receiving
Rise Time
tR
SDA and SCL Receiving
Fall Time
SDA Transmitting Fall
Time
www.maximintegrated.com
900
ns
50
ns
400
pF
20 +
0.1CB
300
ns
tF
20 +
0.1CB
300
ns
tF
20 +
0.1CB
300
ns
Maxim Integrated │ 8
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Electrical Characteristics (continued)
(VDD_ANA = VDD_DIG = 1.8V, VLED = 3.3V, VGND_ANA = VGND_DIG = VPGND = 0V, TA = +25°C, min/max are from TA = -40°C to
+85°C, unless otherwise noted.) (Note 1)
Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by Maxim
Integrated’s bench or proprietary automated test equipment (ATE) characterization.
Note 2: Internal reference only.
Note 3: Specifications are guaranteed by Maxim Integrated’s bench characterization and by 100% production test using proprietary
ATE setup and conditions.
Note 4: For design guidance only. Not production tested.
Note 5: Test conditions: ECG sample rate = 1600Hz, ECG_ADC_OSR[1:0] = 00 (OSR = 16), ECG_ADC_CLK = 0 (25.6kHZ), IA_
GAIN[1:0] = 01 (IA_GAIN = 9.5), and PGA_ECG_GAIN[1:0] = 11 (PGA_GAIN = 8), VCM = 600mV, unless otherwise noted.
Note 6: For measurements with DC difference as input, the highpass filter function is disabled.
SDA
tSU,STA
tSU,DAT
tLOW
tHD,DAT
tHD,STA
tSP
tBUF
tSU,STO
tHIGH
SCL
tHD,STA
tR
tF
START CONDITION
REPEATED START CONDITION
STOP
CONDITION
START
CONDITION
Figure 1. I2C-Compatible Interface Timing Diagram
www.maximintegrated.com
Maxim Integrated │ 9
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
Photoplethysmogram (PPG)
RED LED SUPPLY HEADROOM
80
60
ILED = 50mA
40
0
1
2
3
ILED = 100mA
100
80
60
ILED = 50mA
40
ILED = 20mA
20
toc02
120
ILED = 100mA
100
0
IR LED SUPPLY HEADROOM
toc01
IR LED CURRENT (mA)
RED LED CURRENT (mA)
120
ILED = 20mA
20
0
4
0
1
VLED VOLTAGE (V)
2
VDD SUPPLY CURRENT
vs. SUPPLY VOLTAGE
toc04
250000
LED_PW = 400µs
PPG_SR = 400sps
ADC FULL SCALE = 16384nA
200000
PPG+ECG MODE
0.7
ADC COUNTS
SUPPLY CURRENT (mA)
0.9
0.6
PPG MODE
0.5
0.4
150000
IR
100000
0.3
SHUTDOWN
MODE
0.2
0.1
0.0
50000
RED
0
0.0
0.5
1.0
2.0
1.5
2.5
0
toc05
VLED SHUTDOWN CURRENT (µA)
3.0
VDD = 1.8V
2.5
2.0
1.5
1.0
0.5
20
toc06
0.12
VDD = 2.0V
3.5
15
0.13
4.0
0.0
10
VLED SHUTDOWN CURRENT
vs. TEMPERATURE
VDD SHUTDOWN CURRENT
vs. TEMPERATURE
4.5
5
DISTANCE (mm)
SUPPLY VOLTAGE (V)
VDD SHUTDOWN CURRENT (µA)
4
DC COUNTS vs. DISTANCE FROM
WHITE HIGH IMPACT STYRENE CARD
toc03
1.0
0.8
3
VLED VOLTAGE (V)
VLED = 5.5V
0.11
0.10
0.09
0.08
VLED = 3.1V
0.07
VDD = 1.7V
0.06
-50
0
50
TEMPERATURE (°C)
www.maximintegrated.com
100
-50
0
50
100
TEMPERATURE (°C)
Maxim Integrated │ 10
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
Photoplethysmogram (PPG)
RED LED SPECTRA AT +30°C
IR LED SPECTRA AT +30°C
toc07
100
120
NORMALIZED POWER (%)
NORMALIZED POWER (%)
120
80
60
40
100
80
60
40
20
20
0
0
500
600
700
800
700
800
RED LED PEAK WAVELENGTH
vs. TEMPERATURE
PEAK WAVELENGTH (nm)
PEAK WAVELENGTH (nm)
LED_PW = 400µs
PPG_SR = 400sps
900
665
660
toc10
905
LED_PW = 400µs
PPG_SR = 400sps
670
1000
IR LED PEAK WAVELENGTH
vs. TEMPERATURE
toc09
675
900
WAVELENGTH (nm)
WAVELENGTH (nm)
ILED = 50mA
655
895
ILED = 20mA
890
885
880
ILED = 50mA
875
870
650
865
ILED = 20mA
645
toc08
-50
0
860
50
100
TEMPERATURE (°C)
www.maximintegrated.com
150
-50
0
50
100
150
TEMPERATURE (°C)
Maxim Integrated │ 11
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
Electrocardiogram (ECG)
ECG CHANNEL GAIN vs. FREQUENCY
ECG CHANNEL GAIN vs. TEMPERATURE
toc11
90
toc12
45
40
35
30
80
GAIN (dB)
ECG GAIN (V/V)
85
75
25
20
15
70
10
65
60
5
0
-60
-40
-20
0
20
40
60
80
100
0
20
DC DIFFERENTIAL INPUT RANGE
100
80
100
toc14
8
7
INPUT REFERRED NOISE (µV)
80
CHANNEL GAIN (V/V)
60
NOISE vs. GAIN
toc13
90
70
60
50
40
30
20
6
5
4
3
2
1
10
0
40
FREQUENCY (Hz)
TEMPERATURE (°C)
0
-1.0
-0.5
0.0
0.5
1.0
0
100
200
300
400
500
GAIN (V/V)
DC OFFSET (V)
ADC REFERENCE vs. TEMPERATURE
toc15
1.2175
1.2170
ADC REFERENCE (V)
1.2165
1.2160
1.2155
1.2150
1.2145
1.2140
1.2135
1.2130
1.2125
1.2120
-40
-15
10
35
60
85
TEMPERATURE (°C)
www.maximintegrated.com
Maxim Integrated │ 12
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
INPUT COMMON-MODE
VOLTAGE vs. TEMPERATURE
(ECG_P)
toc16
0.65
0.60
0.55
INPUT IMPEDANCE = 100MΩ
0.50
0.45
-40
-15
10
35
TEMPERATURE (°C)
www.maximintegrated.com
60
0.70
COMMON-MODE VOLTAGE (V)
COMMON-MODE VOLTAGE (V)
0.70
INPUT COMMON-MODE
VOLTAGE vs. TEMPERATURE
ECG_N
85
toc17
0.65
0.60
INPUT IMPEDANCE = 100MΩ
0.55
0.50
0.45
-40
-15
10
35
60
85
TEMPERATURE (°C)
Maxim Integrated │ 13
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Pin Configuration
N.C.
21
C1_P
2
20
C1_N
N.C.
3
19
VREF
ECG_N
4
18
GND_ANA
ECG_P
5
17
GND_DIG
N.C.
1
N.C.
22
MAX86150
N.C.
6
16
PGND
INTB
7
15
VLED
SDA
8
14
VDD_ANA
SCL
9
13
VDD_DIG
N.C.
10
12
N.C.
11
N.C.
www.maximintegrated.com
Maxim Integrated │ 14
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Pin Description
PIN
NAME
1–3, 6,
10–12, 22
N.C.
FUNCTION
N.C.
No Connection. Connect to an unconnected PCB pad for mechanical stability. N.C. pin should not
be connected to any signal, power, or ground pins.
ECG
5
ECG_P
Positive ECG Electrode
4
ECG_N
Negative ECG Electrode
21
C1_P
Capacitor for ECG HPF. Connect to C1_N through a 1μF capacitor.
20
C1_N
Capacitor for ECG HPF. Connect to C1_P through a 1μF capacitor.
CONTROL INTERFACE
8
SDA
I2C Data
9
SCL
I2C Clock
7
INTB
Open-Drain Interrupt
POWER
13
VDD_DIG
Digital Logic Supply. Connect to externally regulated supply. Bypass to GND_DIG.
17
GND_DIG
Digital Logic and Digital Pad Return. Connect to Ground.
14
VDD_ANA
Analog Supply. Connect to externally regulated supply. Bypass to GND_ANA.
18
GND_ANA
Analog Power Return. Connect to Ground.
15
VLED
LED Power Supply Input. Connect to external battery supply. Bypass to PGND.
16
PGND
LED Power Return. Connect to Ground.
VREF
Internal Reference Decoupling Point. Bypass to GND_ANA.
REFERENCE
19
www.maximintegrated.com
Maxim Integrated │ 15
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Functional Diagrams
1μF
1.8V
VDD_DIG
VDD_ANA
C1_N
C1_P
ECG_P
ECG_N
VLED
1.8V
VREF
1μF
3.3V
VREF
ADC
SDA
DIGITAL
CONTROLLER
OR SIGNAL
PROCESSOR
ECG
SCL
INT
RED
IR
VISIBLE + IR
μC
OR
APPLICATIONS
PROCESSOR
ADC
LED DRIVERS
N.C.
N.C.
Detailed Description
PGND
The MAX86150 is a complete electrocardiogram, pulse
oximetry, and heart rate sensor system solution module
designed for the demanding requirements of mobile
devices. The MAX86150 maintains a very small total solution size without sacrificing performance. Minimal external
hardware components are necessary for integration into a
mobile device. The MAX86150 is fully adjustable through
software registers, and the digital output data is stored in
a 32-deep FIFO within the device. The FIFO allows the
MAX86150 to be connected to a microcontroller or processor on a shared bus, where the data is not being read
continuously from the MAX86150’s registers.
www.maximintegrated.com
GND_ANA
GND_DIG
SpO2 Subsystem
The SpO2 subsystem in the MAX86150 is composed
of ambient light cancellation (ALC), a continuous-time
sigma-delta ADC, and proprietary discrete time filter. The
ALC has an internal DAC to cancel ambient light and
increase the effective dynamic range. The internal ADC
is a continuous time oversampling sigma delta converter
with 19-bit resolution. The ADC output data rate can
be programmed from 10sps (samples per second) to
3200sps. The MAX86150 includes a proprietary discrete
time filter to reject 50Hz/60Hz interference and slow moving
residual ambient noise.
Maxim Integrated │ 16
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
LED Driver
The MAX86150 integrates red and infrared LED drivers
to modulate LED pulses for SpO2 and HR measurements. The LED current can be programmed from 0mA to
100mA with proper VLED supply voltage. The LED pulse
width can be programmed from 50μs to 400μs to optimize
accuracy of results and power consumption based on use
cases.
Proximity Function
The MAX86150 includes a proximity function to save
power and reduce visible light emission when the user’s
finger is not on the sensor. Proximity function is enabled
by setting PROX_INT_EN to 1. When the SpO2 or HR
function is initiated, the IR LED is turned on in proximity
mode with a drive current set by the PILOT_PA register.
When an object is detected by exceeding the IR ADC
count threshold (set in the PROX_INT_ THRESH register),
PROX_INT interrupt is asserted and the part transitions
automatically to the normal SpO2/HR mode. To reenter
PROX mode, a new SpO2 or HR reading must be initiated
(even if the value is the same). The proximity function can
be disabled by resetting PROX_INT_EN to 0. In that case,
when the SpO2 or HR function is initiated in the FIFO
Data Control registers, the SpO2 or HR mode begins
immediately.
Electrocardiogram (ECG)
The ECG subsystem in the MAX86150 is designed
specifically for mobile applications. It features single-lead
ECG technology that is optimized for dry electrode operation.
It is comprised of Maxim proprietary analog front end
(AFE), which includes an 18-bit ADC. Figure 2 shows the
ECG Subsystem Block Diagram. The primary function of
the AFE is to digitize heart signals. This process is complicated by the need to reject interference from strong
RF sources, common-mode line frequency, signals from
other muscles, and electrical noise. The electrical
connections to the patient must not create a shock hazard or interfere with other equipment that might be connected to the device. The ECG subsystem also includes
an on-chip highpass filter, which facilitates high SNR in
real applications. The ADC output data rate can be programmed from 200sps (samples per second) to 3200sps.
The output of the ADC is an 18-bit digital representation
of the input voltage. Each data sample takes three bytes
in the FIFO, and the data is right-justified and in bipolar
two's-complement format.
To calculate the equivalent differential input voltage of the
ADC, the formula is as follows:
V_INPUT = ADC_CODE x
12.247μV/IA_GAIN/PGA_GAIN
where ADC_CODE is converted to a bipolar integer decimal
format, which can be positive or negative. Note that only
one gain setting, IA_GAIN = 9.5 and PGA_GAIN = 8, is
trimmed to a tight tolerance at the factory, and the other
gains are typical expected values only.
1μF
1μF
0.6V
ECG_P
C1_P
C1_N
INTERNAL VREF
20kΩ
AC-COULED INSTRUMENTATION
AMPLIFIER
WITH CHOPPING
1.56pF
ECG_N
VREF
20kΩ
X
1.56pF
PGA
INTB,
SDA,
SCL
ΔΣ ADC
DATA
FIFO
X
COMMON-MODE AMPLIFIER
ADC CLOCK
Figure 2. MAX86150 ECG Subsystem Block Diagram
www.maximintegrated.com
Maxim Integrated │ 17
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
ECG and PPG Synchronization
The MAX86155 allows for a simultaneous and synchronous collection of PPG and ECG signals. If the ECG sample rate is set higher than the PPG sample rate, the PPG
sample rate defaults to the ECG sample rate if it can be
supported. If the ECG sample rate is set above the maximum allowable PPG sample rate, then the PPG sample
rate is set to the highest supported rate, and redundant
data will be present in the FLEX FIFO. See Register 0x0E
configuration table “Maximum Sample rates Supported for
all the Pulse Widths and number of LEDs” to determine
which sample rate the PPG defaults to if the ECG is set
higher. For example, if the ECG sample rate is set to
400Hz, and PPG registers are set to 0x0E = 0xDB (Two
LEDs, single pulse, PPG_SR = 100sps, PPG_LED_PW
= 400μs) and Register 0x0F is set to 0x00 (SMP_AVE
= 000, no sample averaging), then the PPG defaults to
400Hz, as this configuration is supported per the table in
0x0E Register description.
Register Map
ADDRESS
NAME
MSB
LSB
Status Registers
0x00
Interrupt Status 1[7:0]
A_FULL_
PPG_
RDY_
ALC_OVF_
PROX_INT_
—
—
—
PWR_
RDY_
0x01
Interrupt Status 2[7:0]
VDD_
OOR_
—
—
—
—
—
—
—
0x02
Interrupt Enable 1[7:0]
A_FULL_
EN_
PPG_
RDY_EN_
ALC_OVF_
EN_
PROX_INT_
EN_
—
—
—
—
0x03
Interrupt Enable 2[7:0]
VDD_
OOR_EN_
—
—
—
—
—
—
—
FIFO Registers
0x04
FIFO Write Pointer[7:0]
—
—
—
FIFO_WR_PTR_[4:0]
0x05
Overflow Counter[7:0]
—
—
—
OVF_COUNTER_[4:0]
0x06
FIFO Read Pointer[7:0]
—
—
—
FIFO_RD_PTR_[4:0]
0x07
FIFO Data Register[7:0]
0x08
FIFO Configuration[7:0]
FIFO_DATA_[7:0]
—
A_FULL_
CLR_
A_FULL_
TYPE_
FIFO_
ROLLS_
ON_FULL_
FIFO_A_FULL_[3:0]
FIFO Data Control
0x09
FIFO Data
Control Register 1[7:0]
FD2_[3:0]
FD1_[3:0]
0x0A
FIFO Data
Control Register 2[7:0]
FD4_[3:0]
FD3_[3:0]
System Control
0x0D
System Control[7:0]
—
—
—
—
—
FIFO_EN_
SHDN_
RESET_
PPG Configuration
0x0E
PPG Configuration
1[7:0]
0x0F
PPG Configuration
2[7:0]
0x10
Prox Interrupt Threshold[7:0]
www.maximintegrated.com
PPG_ADC_RGE_[1:0]
—
—
PPG_LED_PW_
[1:0]
PPG_SR_[3:0]
—
—
—
SMP_AVE_[2:0]
PROX_INT_THRESH_[7:0]
Maxim Integrated │ 18
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Register Map (continued)
LED Pulse Amplitude
0x11
LED1 PA[7:0]
0x12
LED2 PA[7:0]
0x14
LED Range[7:0]
0x15
LED PILOT PA[7:0]
LED1_PA_[7:0]
LED2_PA_[7:0]
—
—
—
—
LED2_RGE_[7:0]
LED1_RGE_[7:0]
PILOT_PA_[7:0]
ECG Configuration
0x3C
ECG Configuration
1[7:0]
—
—
—
—
0x3E
ECG Configuration
3[7:0]
—
—
—
—
—
ECG_
ADC_
CLK_
ECG_ADC_OSR_
[1:0]
PGA_ECG_
GAIN_[1:0]
IA_GAIN_[1:0]
Part ID
0xFF
Part ID[7:0]
PART_ID_[7:0]
Register Details
Interrupt Status 1 (0x00)
BIT
Field
Reset
Access Type
7
6
5
4
3
2
1
0
A_FULL
PPG_RDY
ALC_OVF
PROX_INT
—
—
—
PWR_RDY
0x0
0x0
0x0
0x0
—
—
—
0x0
Read Only
Read Only
Read Only
Read Only
—
—
—
Read Only
A_FULL: FIFO Almost Full Flag
VALUE
ENUMERATION
DECODE
0
OFF
Normal Operation
1
ON
Indicates that the FIFO buffer overflows the threshold set by FFIFO_A_FULL[3:0] on the next
sample. This bit is cleared when the Interrupt Status 1 register is read. It is also cleared when
FIFO_DATA register is read, if A_FULL_CLR = 1
PPG_RDY: New PPG FIFO Data Ready
VALUE
ENUMERATION
0
OFF
Normal Operation
1
ON
In SpO2 and HR modes, this interrupt triggers when there is a new sample in the data FIFO.
The interrupt is cleared by reading the Interrupt Status 1 register (0x00), or by reading the
FIFO_DATA register.
www.maximintegrated.com
DECODE
Maxim Integrated │ 19
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
ALC_OVF: Ambient Light Cancellation Overflow
VALUE
ENUMERATION
DECODE
0
OFF
Normal Operation
1
ON
This interrupt triggers when the ambient light cancellation function of the SpO2/HR photodiode
has reached its maximum limit due to overflow, and therefore, ambient light is affecting the
output of the ADC. The interrupt is cleared by reading the Interrupt Status 1 register (0x00).
PROX_INT: Proximity interrupt
If PROX_INT is masked then the prox mode is disabled and the select PPG begins immediately. This bit is cleared when
the Interrupt Status 1 Register is read.
VALUE
ENUMERATION
0
OFF
Normal Operation
DECODE
1
ON
Indicates that the proximity threshold has been crossed when in proximity mode.
PWR_RDY: Power Ready Flag
VALUE
ENUMERATION
DECODE
0
OFF
Normal Operation
1
ON
Indicates that VBATT went below the UVLO threshold. This bit is not triggered by a soft reset.
This bit is cleared when Interrupt Status 1 Register is read.
Interrupt Status 2 (0x01)
BIT
Field
Reset
Access Type
7
6
5
4
3
2
1
0
VDD_OOR
—
—
—
—
ECG_RDY
—
—
0x0
—
—
—
—
0x0
—
—
Read Only
—
—
—
—
Read Only
—
—
VDD_OOR: VDD Out-of-Range Flag
This flag checks if the VDD_ANA supply voltage is outside supported range.
VALUE
ENUMERATION
DECODE
0
OFF
VDD_ANA between range.
1
ON
Indicated that VDD_ANA is greater than 2.05V or less than 1.65V. This bit is automatically
cleared when the Interrupt Status 2 register is read. The detection circuitry has a 10ms delay
time and continues to trigger as long as the VDD_ANA is out of range.
ECG_RDY: New ECG FIFO Data Ready
This flag checks if the VDD_ANA supply voltage is outside supported range.
VALUE
ENUMERATION
0
OFF
Normal Operation
1
ON
Indicates that the ECG ADC has finished it’s existing conversion.
www.maximintegrated.com
DECODE
Maxim Integrated │ 20
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Interrupt Enable 1 (0x02)
BIT
7
6
5
4
3
2
1
0
Field
A_FULL_EN
PPG_RDY_
EN
ALC_OVF_
EN
PROX_INT_
EN
—
—
—
—
Reset
0x0
0x0
0x0
0x0
—
—
—
—
Write, Read
Write, Read
Write, Read
Write, Read
—
—
—
—
Access Type
A_FULL_EN: FIFO Almost Full Flag Enable
VALUE
ENUMERATION
0
OFF
A_FULL interrupt is disabled
DECODE
1
ON
A_FULL interrupt is enabled
PPG_RDY_EN: New PPG FIFO Data Ready Interrupt enable
VALUE
ENUMERATION
DECODE
0
OFF
PPG_RDY interrupt is disabled
1
ON
PPG_RDY interrupt is enabled.
ALC_OVF_EN: Ambient Light Cancellation (ALC) Overflow Interrupt Enable
The ALC_OVF flag is triggered when the ambient light cancellation function has reached its maximum limit due to overflow. At this point, the ADC output is affected by the ambient light.
VALUE
ENUMERATION
DECODE
0
OFF
ALC_OVF interrupt is disabled
1
ON
ALC_OVF interrupt is enabled
PROX_INT_EN: Proximity Interrupt Enable
When the FIFO Data Control Register is configured to initiate PPG measurement, the IR LED is turned on in proximity
mode with a drive current set by the PILOT_PA register. When an object is detected by exceeding the IR ADC count
threshold (set in the PROX_INT_ THRESH register), PROX_INT interrupt is asserted and the part transitions to the
normal SpO2/HR mode.
VALUE
ENUMERATION
0
OFF
PROX_INT interrupt is disabled
1
ON
PROX_INT interrupt is enabled
www.maximintegrated.com
DECODE
Maxim Integrated │ 21
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Interrupt Enable 2 (0x03)
BIT
7
6
5
4
3
2
1
0
Field
VDD_OOR_
EN
—
—
—
—
ECG_
RDY_ EN
—
—
Reset
0x0
—
—
—
—
0x0
—
—
Write, Read
—
—
—
—
Write, Read
—
—
1
0
Access Type
VDD_OOR_EN: VDD Out-of-Range Indicator Enable
VALUE
ENUMERATION
DECODE
0
OFF
Disables the VDD_OVR interrupt
1
ON
Enables the VDD_OVR interrupt
ECG_RDY_EN: New ECG FIFO Data Ready Interrupt Enable
VALUE
ENUMERATION
0
OFF
ECG_RDY interrupt is disabled
DECODE
1
ON
ECG_RDY interrupt is enabled
FIFO Write Pointer (0x04)
7
6
5
Field
BIT
—
—
—
4
3
2
Reset
—
—
—
0x00
Access Type
—
—
—
Write, Read
FIFO_WR_PTR[4:0]
FIFO_WR_PTR: FIFO Write Pointer
This points to the location where the next sample is written. This pointer advances for each sample pushed on to the
FIFO.
www.maximintegrated.com
Maxim Integrated │ 22
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Overflow Counter (0x05)
BIT
7
6
5
4
3
2
Field
—
—
—
OVF_COUNTER[4:0]
Reset
—
—
—
0x00
Access Type
—
—
—
Read Only
1
0
OVF_COUNTER: FIFO Overflow Counter
When FIFO is full, any new samples result in new or old samples getting lost depending on FIFO_ROLLS_ON_FULL.
OVF_COUNTER counts the number of samples lost. It saturates at 0x1F.
FIFO Read Pointer (0x06)
7
6
5
Field
BIT
—
—
—
4
3
2
Reset
—
—
—
0x00
Access Type
—
—
—
Write, Read
1
0
FIFO_RD_PTR[4:0]
FIFO_RD_PTR: FIFO Read Pointer
The FIFO Read Pointer points to the location from where the processor gets the next sample from the FIFO through the
I2C interface. This advances each time a sample is popped from the FIFO. The processor can also write to this pointer
after reading the samples. This allows rereading (or retrying) samples from the FIFO.
www.maximintegrated.com
Maxim Integrated │ 23
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
FIFO Data Register (0x07)
BIT
7
6
5
4
3
Field
FIFO_DATA[7:0]
Reset
0x00
Access Type
2
1
0
Write, Read
FIFO_DATA: FIFO Data Register
This is a read-only register and is used to get data from the FIFO. See FIFO Description for more details.
FIFO Configuration (0x08)
BIT
7
6
5
4
3
2
1
Field
—
A_FULL_
CLR
A_FULL_
TYPE
FIFO_
ROLLS_
ON_FULL
FIFO_A_FULL[3:0]
Reset
—
0x0
0x0
0x0
0xF
Access Type
—
Write, Read
Write, Read
Write, Read
Write, Read
0
A_FULL_CLR: FIFO Almost Full Interrupt Options
This defines whether the A-FULL interrupt should get cleared by FIFO_DATA register read.
VALUE
ENUMERATION
0
RD_DATA_NOCLR
1
RD_DATA_CLR
DECODE
A_FULL interrupt does not get cleared by FIFO_DATA register read. It gets cleared by
status register read.
A_FULL interrupt gets cleared by FIFO_DATA register read or status register read.
A_FULL_TYPE: FIFO Almost Full Flag Options
This defines the behavior of the A_FULL interrupt.
VALUE
ENUMERATION
DECODE
0
AFULL_RPT
A_FULL interrupt gets asserted when the a_full condition is detected. It is cleared by status
register read, but re-asserts for every sample if the a_full condition persists.
1
AFULL_ONCE
www.maximintegrated.com
A_FULL interrupt gets asserted only when the a_full condition is detected. The interrupt
gets cleared on status register read, and does not re-assert for every sample until a new
a-full condition is detected.
Maxim Integrated │ 24
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
FIFO_ROLLS_ON_FULL: FIFO Rolls on Full Options
This bit controls the behavior of the FIFO when the FIFO becomes completely filled with data.
When the device is in PROX mode, the FIFO always rolls on full.
●● Push to FIFO is enabled when FIFO is full if FIFO_ROLLS_ON_FULL = 1 and old samples are lost. Both FIFO_
WR_PTR and FIFO_RD_PTR increment for each sample after the FIFO is full.
●● Push to FIFO is disabled when FIFO is full if FIFO_ROLLS_ON_FULL = 0 and new samples are lost. FIFO_WR_
PTR does not increment for each sample after the FIFO is full.
VALUE
ENUMERATION
DECODE
0
OFF
The FIFO stops on full.
1
ON
The FIFO automatically rolls over on full.
FIFO_A_FULL: FIFO Almost Full Value
These bits indicate how many new samples can be written to the FIFO before the interrupt is asserted. For example, if
set to 0xF, the interrupt triggers when there is 17 empty space left (15 data samples), and so on.
FIFO_A_FULL
FREE SPACE BEFORE INTERRUPT
# OF SAMPLES IN FIFO
0000
0
32
0001
1
31
0010
2
30
0011
3
29
----
----
----
1110
14
18
1111
15
17
www.maximintegrated.com
Maxim Integrated │ 25
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
FIFO Data Control Register 1 (0x09)
BIT
7
6
5
4
3
2
1
Field
FD2[3:0]
FD1[3:0]
Reset
0x0
0x0
Write, Read
Write, Read
Access Type
0
FD2: FIFO Data Time Slot 2
These bits set the data type for element 2 of the FIFO.
The FIFO can hold up to 32 samples. Each sample can hold up to four elements and each element is 3 bytes wide. The
data type that gets stored in the 3 bytes is configured by FD1, FD2, FD3 and FD4 according to the following table. For
restriction on data type sequences, see the FIFO Description section.
FD2[3:0]
DATA TYPE
FD2[3:0]
DATA TYPE
FD2[3:0]
DATA TYPE
FD2[3:0]
DATA TYPE
0000
None
0100
Reserved
1000
Reserved
1100
Reserved
0001
PPG_LED1
0101
Pilot LED1
1001
ECG
1101
Reserved
0010
PPG_LED2
0110
Pilot LED2
1010
Reserved
1110
Reserved
0011
Reserved
Reserved
Reserved
Reserved
Reserved
1111
Reserved
FD1: FIFO Data Time Slot 1
These bits set the data type for element 1 of the FIFO.
The FIFO can hold up to 32 samples. Each sample can hold up to four elements and each element is 3 bytes wide. The
data type that gets stored in the 3 bytes is configured by FD1, FD2, FD3 and FD4 according to the following table. For
restriction on data type sequences, see the FIFO Description section.
FD1[3:0]
DATA TYPE
FD1[3:0]
DATA TYPE
FD1[3:0]
DATA TYPE
FD1[3:0]
DATA TYPE
0000
None
0001
PPG_LED1
0100
Reserved
1000
Reserved
1100
Reserved
0101
Pilot LED1
1001
ECG
1101
Reserved
0010
0011
PPG_LED2
0110
Pilot LED2
1010
Reserved
1110
Reserved
Reserved
0111
Reserved
1011
Reserved
1111
Reserved
www.maximintegrated.com
Maxim Integrated │ 26
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
FIFO Data Control Register 2 (0x0A)
BIT
7
6
5
4
3
2
1
Field
FD4[3:0]
FD3[3:0]
Reset
0x0
0x0
Write, Read
Write, Read
Access Type
0
FD4: FIFO Data Time Slot 4
These bits set the data type for element 4 of the FIFO.
The FIFO can hold up to 32 samples. Each sample can hold up to four elements and each element is 3 bytes wide. The
data type that gets stored in the 3 bytes is configured by FD1, FD2, FD3 and FD4 according to the following table. For
restriction on data type sequences, see the FIFO Description section.
FD4[3:0]
DATA TYPE
FD4
DATA TYPE
FD4
DATA TYPE
FD4
DATA TYPE
0000
None
0100
Reserved
1000
Reserved
1100
Reserved
0001
PPG_LED1
0101
Pilot LED1
1001
ECG
1101
Reserved
0010
PPG_LED2
0110
Pilot LED2
1010
Reserved
1110
Reserved
0011
Reserved
0111
Reserved
1011
Reserved
1111
Reserved
FD3: FIFO Data Time Slot 3
These bits set the data type for element 3 of the FIFO.
The FIFO can hold up to 32 samples. Each sample can hold up to four elements and each element is 3 bytes wide. The
data type that gets stored in the 3 bytes is configured by FD1, FD2, FD3 and FD4 according to the following table. For
restriction on data type sequences please refer to the FIFO Description section.
FD3[3:0]
DATA TYPE
FD3
DATA TYPE
FD3
DATA TYPE
FD3
DATA TYPE
0000
None
0100
Reserved
1000
Reserved
1100
Reserved
0001
PPG_LED1
0101
Pilot LED1
1001
ECG
1101
Reserved
0010
PPG_LED2
0110
Pilot LED2
1010
Reserved
1110
Reserved
0011
Reserved
0111
Reserved
1011
Reserved
1111
Reserved
www.maximintegrated.com
Maxim Integrated │ 27
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
System Control (0x0D)
BIT
7
6
5
4
3
2
1
0
Field
—
—
—
—
—
FIFO_EN
SHDN
RESET
Reset
—
—
—
—
—
0x0
0x0
0x0
Access Type
—
—
-
—
—
Write, Read
Write, Read
Write, Read
FIFO_EN: FIFO Enable
VALUE
ENUMERATION
DECODE
0
OFF
Push to FIFO is disabled, but the read and write pointers and the data in the FIFO are all
held at their values before FIFO_EN is set to 0.
1
ON
The FIFO is enabled. When this bit is set the FIFO is flushed of all old data and the new
samples start loading from pointer zero.
SHDN: Shutdown Control
The part can be put into a power-save mode by setting this bit to one. While in power-save mode, all registers retain their
values, and write/read operations function as normal. All interrupts are cleared to zero in this mode.
VALUE
ENUMERATION
0
OFF
The part is in normal operation. No action taken.
ON
The part can be put into a power-save mode by writing a ‘1’ to this bit. While in this mode
all registers remain accessible and retain their data. ADC conversion data contained in the
registers are previous values. Writable registers also remain accessible in shutdown. All
interrupts are cleared. In this mode the oscillator is shutdown and the part draws minimum
current. If this bit is asserted during a active conversion then the conversion completes
before the part shuts down.
1
DECODE
RESET: Reset Control
When this bit is set The part under-goes a forced power-on-reset sequence. All configuration, threshold and data
registers including distributed registers are reset to their power-on-state. This bit then automatically becomes ‘0’ after the
reset sequence is completed.
VALUE
ENUMERATION
0
OFF
The part is in normal operation. No action taken.
1
ON
The part under-goes a forced power-on-reset sequence. All configuration, threshold and
data registers including distributed registers are reset to their power-on-state. This bit then
automatically becomes ‘0’ after the reset sequence is completed.
www.maximintegrated.com
DECODE
Maxim Integrated │ 28
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
PPG Configuration 1 (0x0E)
BIT
7
6
5
4
3
2
1
0
Field
PPG_ADC_RGE[1:0]
PPG_SR[3:0]
PPG_LED_PW[1:0]
Reset
0x0
0x0
0x0
Write, Read
Write, Read
Write, Read
Access Type
PPG_ADC_RGE: SpO2 ADC Range Control
These bits set the ADC range of the SPO2 sensor as shown in the table below.
PPG_ADC_RGE
LSB [pA]
FULL SCALE [nA]
00
7.8125
4096
01
15.625
8192
10
31.25
16384
11
62.5
32768
PPG_SR: SpO2 Sample Rate Control
SpO2 Sample Rate Control
These bits set the effective sampling rate of the PPG sensor as shown in the table below.
Note: If a sample rate is set that can not be supported by the selected pulse width and LED mode then the highest available sample rate will be automatically set. The user can read back this register to confirm the sample rate.
PPG_SR
SAMPLES PER SECOND
PULSES PER SAMPLE, N
0000
10
1
0001
20
1
0010
50
1
0011
84
1
0100
100
1
0101
200
1
0110
400
1
0111
800
1
1000
1000
1
1001
1600
1
1010
3200
1
1011
10
2
1100
20
2
1101
50
2
1110
84
2
1111
100
2
www.maximintegrated.com
Maxim Integrated │ 29
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Maximum sample rates supported for all the pulse widths and number of LEDs:
NUMBER OF ADC CONVERSIONS
PER SAMPLE
PPG_LED_PW = 0
(50µs)
PPG_LED_PW = 1
(100µs)
PPG_LED_PW = 2
(200µs)
PPG_LED_PW = 3
(400µs)
1 LED, N=1
3200
1600
1000
1000
2 LED, N=1
1600
800
800
400
1 LED, N=2
100
100
100
100
2 LED, N=2
100
100
100
84
PPG_LED_PW: LED Pulse Width Control
These bits set the pulse width of the LED drivers and the integration time of PPG ADC as shown in the table below.
PPG_LED_PW
PULSE WIDTH [µs]
INTEGRATION TIME [µs]
RES BITS
00
50
50
19
01
100
100
19
10
200
200
19
11
400
400
19
PPG Configuration 2 (0x0F)
7
6
5
4
3
Field
BIT
—
—
—
—
—
2
1
Reset
—
—
—
—
—
0x0
Access Type
—
—
—
—
—
Write, Read
0
SMP_AVE[2:0]
SMP_AVE: Sample Averaging Options
To reduce the amount of data throughput, adjacent samples (in each individual channel) can be averaged and decimated
on the chip by setting this register.
These bits set the number of samples that are averaged on chip before being written to the FIFO.
www.maximintegrated.com
SMP_AVE[2:0]
SAMPLE AVERAGE
000
1 (no averaging)
001
2
010
4
011
8
100
16
101
32
110
32
111
32
Maxim Integrated │ 30
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Prox Interrupt Threshold (0x10)
BIT
7
6
5
4
3
Field
PROX_INT_THRESH[7:0]
Reset
0x00
Access Type
2
1
0
Write, Read
PROX_INT_THRESH: Proximity Mode Interrupt Threshold*
This register sets the IR ADC count that triggers the beginning of the PPG mode specified in the FIFO Data Control
Register. The threshold is defined as the 8 MSB bits of the ADC count. For example, if PROX_INT_THRESH[7:0] = 0x01,
then an ADC value of 1023 (decimal) or higher triggers the PROX interrupt. If PROX_INT_THRESH[7:0] = 0xFF, then
only a saturated ADC triggers the interrupt.
LED1 PA (0x11)
BIT
7
6
5
4
Field
3
2
1
0
LED1_PA[7:0]
Reset
0x00
Access Type
Write, Read
LED1_PA: LED 1 (IR) Current Pulse Amplitude.
These bits set the nominal current pulse amplitude of LED 1 as shown in the table below.
LED1_RGE[1:0]
00 (50mA)
01 (100mA)
LED1_PA[7:0]
LED Current [mA]
LED Current [mA]
00000000
0
0
00000001
0.2
0.4
00000010
0.4
0.8
00000011
0.6
1.2
11111100
50.4
100.8
11111101
50.6
101.2
11111110
50.8
101.6
11111111
51
102
LSB
0.2
0.4
............
www.maximintegrated.com
Maxim Integrated │ 31
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
LED2 PA (0x12)
BIT
7
6
5
4
3
Field
LED2_PA[7:0]
Reset
0x00
Access Type
2
1
0
Write, Read
LED2_PA: LED 2 (RED) Current Pulse Amplitude
These bits set the nominal current pulse amplitude of LED 2 as shown in the table below.
LED2_RGE[1:0]
00(50mA)
01(100mA)
LED2_PA[7:0]
LED Current[mA]
LED Current[mA]
00000000
0
0
00000001
0.2
0.4
00000010
0.4
0.8
00000011
0.6
1.2
11111100
50.4
100.8
11111101
50.6
101.2
11111110
50.8
101.6
11111111
51
102
LSB
0.2
0.4
............
LED Range (0x14)
BIT
7
6
5
4
3
2
1
0
Field
—
—
—
—
LED2_RGE[1:0]
Reset
—
—
—
—
0x00
0x00
Access Type
—
—
—
—
Write, Read
Write, Read
LED1_RGE[1:0]
LED2_RGE: LED 2 Current Control
Range selection of the LED current. Refer to LED2_PA[7:0] for more details.
LED2_RGE
LED CURRENT (mA)
00
50
01
100
10
Not Applicable
11
Not Applicable
LED1_RGE: LED 1 Current Control
Range selection of the LED current. Refer to LED1_PA[7:0] for more details.
LED1_RGE
LED CURRENT (mA)
00
50
01
100
10
Not Applicable
11
Not Applicable
www.maximintegrated.com
Maxim Integrated │ 32
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
LED PILOT PA (0x15)
BIT
7
6
5
4
Field
3
2
1
0
PILOT_PA[7:0]
Reset
0x00
Access Type
Write, Read
PILOT_PA: Proximity Mode LED Pulse Amplitude.
The purpose of PILOT_PA[7:0] is to set the LED power during the PROX mode, as well as in Multi-LED mode. These
bits set the current pulse amplitude for the pilot mode as shown in the table below.
When LED x is used, the respective LEDx_RGE is used to control the range of the LED driver in conjunction with
PILOT_PA[7:0]. For instance, if LED1 is used in the PILOT mode, then, LED1_RGE[1:0] together with PILOT_PA[7:0]
will be used to set the LED1 current.
LEDx_RGE[1:0]
00 (50mA)
01 (100mA)
PILOT_PA[7:0]
LED Current[mA]
LED Current[mA]
00000000
0
0
00000001
0.2
0.4
00000010
0.4
0.8
00000011
0.6
1.2
11111100
50.4
100.8
11111101
50.6
101.2
11111110
50.8
101.6
11111111
51
102
LSB
0.2
0.4
............
www.maximintegrated.com
Maxim Integrated │ 33
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
ECG Configuration 1 (0x3C)
BIT
7
6
5
4
3
2
1
0
Field
—
—
—
—
—
ECG_ADC_
CLK
ECG_ADC_OSR[1:0]
Reset
—
—
—
—
—
0x0
0x0
Access Type
—
—
—
—
—
Write, Read
Write, Read
ECG_ADC_CLK: Please refer to ECG_ADC_OSR
ECG_ADC_OSR: ECG ADC Oversampling Ratio
These bit sets the over sampling ratio (OSR) of the ECG ADC. ECG_ADC_OSR together with the ADC clock
frequency (ECG_ADC_CLK) set the ECG sample rate. The following table shows typical values only.
{ECG_ADC_CLK, ECG_ADC_
OSR[1:0]}
ECG SAMPLE RATE
FILTER
BANDWIDTH (70%)
FILTER
BANDWIDTH (90%)
UNITS
000
1600
420
232
Hz
001
800
210
116
Hz
010
400
105
58
Hz
011
200
52
29
Hz
100
3200
840
464
Hz
101
1600
420
232
Hz
110
800
210
116
Hz
111
400
105
58
Hz
www.maximintegrated.com
Maxim Integrated │ 34
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
ECG Configuration 3 (0x3E)
BIT
7
6
5
4
3
2
1
0
Field
—
—
—
—
PGA_ECG_GAIN[1:0]
IA_GAIN[1:0]
Reset
—
—
—
—
0x0
0x2
Access Type
—
—
—
—
Write, Read
Write, Read
PGA_ECG_GAIN: ECG PGA Gain Options
These bit set the gain of the ECG PGA as shown below.
PGA_ECG_GAIN
GAIN
UNITS
00
1
V/V
01
2
V/V
10
4
V/V
11
8
V/V
IA_GAIN: Instrumentation Amplifier Gain Options
These bit set the gain of the Instrumental Amplifier (IA) AFE as shown below.
IA_GAIN
GAIN
UNITS
00
5
V/V
01
9.5
V/V
10
20
V/V
11
50
V/V
Part ID (0xFF)
BIT
7
6
5
Field
Reset
Access Type
4
3
2
1
0
PART_ID[7:0]
0x1E
Read Only
PART_ID: Part Identifier
This register stores the Part identifier for the chip.
www.maximintegrated.com
Maxim Integrated │ 35
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Applications Information
Power Sequencing and Requirements
Power-Up Sequencing
It is recommended to power the VDD_ANA supply first,
followed by the VDD_DIG and the LED power supplies
(VLED). VDD_ANA and VDD_DIG can be powered on at
the same time. The interrupt and I2C pins can be pulled
up to an external voltage even when the power supplies
are not powered up.
After the power is established, an interrupt occurs to alert
the system that the sensor is ready for operation. Reading
the I2C interrupt register clears the interrupt, as shown in
the Figure 3.
Power-Down Sequencing
The sensor is designed to be tolerant of any power-supply
sequencing on power-down.
I2C Interface
The MAX86150 features an I2C/SMBus-compatible,
2-wire serial interface consisting of a serial data line (SDA)
and a serial clock line (SCL). SDA and SCL facilitate
communication between the MAX86150 and the master
at clock rates up to 400kHz. The master generates SCL
and initiates data transfer on the bus. The master device
writes data to the MAX86150 by transmitting the proper
slave address followed by data. Each transmit sequence
is framed by a START (S) or REPEATED START (Sr)
condition and a STOP (P) condition. Each word transmitted
to the MAX86150 is 8 bits long and is followed by an
acknowledge clock pulse. A master reading data from the
MAX86150 transmits the proper slave address followed
by a series of nine SCL pulses.
The MAX86150 transmits data on SDA in sync with the
master-generated SCL pulses. The master acknowledges
receipt of each byte of data. Each read sequence is
framed by a START (S) or REPEATED START (Sr) condition, a not acknowledge, and a STOP (P) condition. SDA
operates as both an input and an open-drain output. A
pullup resistor, typically greater than 1000Ω, is required
on SDA. SCL operates only as an input. A pullup resistor,
typically greater than 1000Ω, is required on SCL if there
are multiple masters on the bus, or if the single master
has an open-drain SCL output. Series resistors in line with
SDA and SCL are optional. Series resistors protect the
digital inputs of the MAX86150 from high-voltage spikes
on the bus lines and minimize crosstalk and undershoot
of the bus signals.
VDD_ANA
VDD_DIG
VLED
INT
SDA, SCL
PWR_RDY INTERRUPT
HIGH (I/O PULLUP)
READ TO CLEAR
INTERRUPT
HIGH (I/O PULLUP)
Figure 3. Power-Up Sequence of the Power Supply Rails
www.maximintegrated.com
Maxim Integrated │ 36
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Bit Transfer
Slave Address
One data bit is transferred during each SCL cycle. The
data on SDA must remain stable during the high period
of the SCL pulse. Changes in SDA while SCL is high are
control signals. See the START and STOP Conditions
section.
A bus master initiates communication with a slave device
by issuing a START condition followed by the 7-bit slave
ID. When idle, the MAX86150 waits for a START condition
followed by its slave ID. The serial interface compares
each salve ID bit by bit, allowing the interface to power
down and disconnect from SCL immediately if an incorrect
slave ID is detected. After recognizing a START
condition followed by the correct slave ID, the MAX86150
is programmed to accept or send data. The LSB of the
slave ID word is the read/write (R/W) bit. R/W indicates
whether the master is writing to or reading data from the
MAX86150 (R/W = 0 selects a write condition, R/W = 1
selects a read condition). After receiving the proper slave
ID, the MAX86150 issues an ACK by pulling SDA low for
one clock cycle.
START and STOP Conditions
SDA and SCL idle high when the bus is not in use. A
master initiates communication by issuing a START
condition. A START condition is a high-to-low transition
on SDA with SCL high. A STOP condition is a low-to-high
transition on SDA while SCL is high . A START condition
from the master signals the beginning of a transmission
to the MAX86150. The master terminates transmission,
and frees the bus, by issuing a STOP condition. The
bus remains active if a REPEATED START condition is
generated instead of a STOP condition. Figure 4 shows
the START, STOP, and REPEATED START of the I2C
conditions
The MAX86150 slave ID consists of seven fixed bits,
B7–B1 (set to 0b1011110). The most significant slave ID
bit (B7) is transmitted first, followed by the remaining bits.
Early STOP Conditions
B7 B6 B5 B4 B3 B2 B1 B0
The MAX86150 recognizes a STOP condition at any point
during data transmission except if the STOP condition
occurs in the same high pulse as a START condition. For
proper operation, do not send a STOP condition during
the same SCL high pulse as the START condition.
S
1
Sr
0
1
1
1
1
0 RW
WRITE
READ
ADDRESS ADDRESS
0xBC
0xBD
P
SCL
SDA
Figure 4. START, STOP, and REPEATED START Conditions
www.maximintegrated.com
Maxim Integrated │ 37
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Acknowledge
read mode. An acknowledge is sent by the master after
each read byte to allow data transfer to continue. A not
acknowledge is sent when the master reads the final byte
of data from the MAX86150, followed by a STOP condition.
The acknowledge bit (ACK) as shown in Figure 5 is a
clocked 9th bit that the MAX86150 uses to handshake
receipt each byte of data when in write mode. The
MAX86150 pulls down SDA during the entire mastergenerated 9th clock pulse if the previous byte is
successfully received. Monitoring ACK allows for detection
of unsuccessful data transfers. An unsuccessful data
transfer occurs if a receiving device is busy or if a system
fault has occurred. In the event of an unsuccessful data
transfer, the bus master retries communication. The
master pulls down SDA during the 9th clock cycle to
acknowledge receipt of data when the MAX86150 is in
Write Data Format
For the write operation, send the slave ID as the first byte
followed by the register address byte and then one or
more data bytes. The register address pointer increments
automatically after each byte of data received, so for
example the entire register bank can be written by at one
time. Terminate the data transfer with a STOP condition.
The write operation is shown in the Figure 6.
CLOCK PULSE FOR
ACKNOWLEDMENT
START
CONDITION
SCL
1
2
8
9
NOT ACKNOWLEDGE
SDA
ACKNOWLEDGE
Figure 5. I2C Acknowledge
S
1
1
0
1
1
1
0
R/W
=0
ACK
A7
D6
D5
D4
D3
A5
A4
A3
A2
A1
A0
ACK
REGISTER ADDRESS
SLAVE ID
D7
A6
D2
D1
D0
ACK
P
DATA BYTE
S = START CONDITION
P= STOP CONDITION
ACK = ACKNOWLEDGE BY THE RECEIVER
INTERNAL ADDRESS POINTER AUTOINCREMENT(FOR
WRITING MULTIPLE BYTES)
Figure 6. Writing One Data Byte to MAX86150
www.maximintegrated.com
Maxim Integrated │ 38
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Read Data Format
For the read operation, two I2C operations must be
performed. First, the slave ID byte is sent followed by the
I2C register that you wish to read. Then a REPEAT START
(Sr) condition is sent, followed by the read slave ID. The
MAX86150 then begins sending data beginning with the
register selected in the first operation. The read pointer
increments automatically, so the MAX86150 continues
sending data from additional registers in sequential order
until a STOP (P) condition is received. The exception to
this is the FIFO_DATA register, at which the read pointer no
longer increments when reading additional bytes. To read
the next register after FIFO_DATA, an I2C write command
is necessary to change the location of the read pointer.
Figure 7 and Figure 8 show the process of reading one
byte or multiple bytes of data respectively.
An initial write operation is required to send the read
register address.
Data is sent from registers in sequential order, starting
from the register selected in the initial I2C write operation.
If the FIFO_DATA register is read, the read pointer does
not automatically increment, and subsequent bytes of
data contain the contents of the FIFO.
Figure 7. Reading One Byte of Data from MAX86150
S
1
0
1
1
1
1
0
R/W
=0
ACK
A7
A6
A5
1
0
1
1
1
1
0
R/W
=1
ACK
D7
D6
D5
D6
D5
D4
D3
D2
D1
D0
AM
D7
D6
A1
A0
ACK
D4
D3
D2
D1
D0
AM
D5
D4
D3
D2
D1
D0
NACK
P
DATA n
DATA n-1
S = START CONDITION
Sr = REPEATED START CONDITION
P= STOP CONDITION
A2
DATA 1
DATA BYTE
D7
A3
REGISTER ADDRESS
SLAVE ID
Sr
A4
ACK = ACKNOWLEDGE BY THE RECEIVER
NACK = NOT ACKNOWLEDGE
AM = ACKNOWLEDGE BY THE MASTER
Figure 8. Reading Multiple Bytes of Data from the MAX86150
www.maximintegrated.com
Maxim Integrated │ 39
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
FIFO Description
Each sample comprises of up to four elements. The
actual number of elements in a sample depends on:
Overview
●● FIFO Data Control Register 1
The FLEX FIFO is designed to support configurable
number of elements. So the number of elements in each
sample is configurable. All elements are of same width,
but can be interpreted differently, depending on how the
FIFO data is configured. MS bits of any element that is
smaller than this width is padded with zeroes. Reading
FIFO through the I2C returns only the active FIFO data
corresponding to the current configuration.
●● FIFO Data Control Register 2
FIFO Data Types
FIFO Data Control Registers
Table 1 shows the FIFO Data Control registers that are
used for enabling any of the PPG modes (e.g., HR, SpO2,
etc), ECG mode.
The design is also scalable to support any:
FD1, FD2, FD3, and FD4 (FDx[3:0]) are configured as
shown in the Table 2 to hold data as programmed. It also
shows the format of the data in the FIFO.
●● Element width in number of bits
●● Sample length in number of elements
●● FIFO depth in number of samples
Table 1. FIFO Data Control registers
ADDRESS
REGISTER
NAME
HARDWIRED
VALUE
0x09
FIFO Data
Configuration
Register 1
00
FD2[3:0]
FD1[3:0]
0x0A
FIFO Data
Configuration
Register 2
00
FD4[3:0]
FDS3[3:0]
B7
B6
B5
B4
B3
B2
B1
B0
Table 2. FDx Format Configurations
FDX[3:0]
DATA TYPE
0000
None
N/A
0001
PPG
PPG_DATA[18:0] for LED1 (IR)
MS bits should be masked
0010
PPG
PPG_DATA[18:0] for LED2 (Red)
MS bits should be masked
0011
Reserved
Reserved
0100
Reserved
Reserved
0101
PPG
PPG_DATA[18:0] for Pilot LED1 (IR)
MS bits should be masked
0110
PPG
PPG_DATA[18:0] for Pilot LED2 (Red)
MS bits should be masked
0111
Reserved
Reserved
1000
Reserved
Reserved
1001
ECG
ECG_DATA[17:0]
1010
Reserved
Reserved
1011
Reserved
Reserved
1100
Reserved
Reserved
1101
Reserved
Reserved
1110
Reserved
Reserved
1111
Reserved
Reserved
www.maximintegrated.com
FIFO CONTENT OR DATA DESCRIPTION
NOTE
MS bits padded with zeroes
Maxim Integrated │ 40
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
If a configuration uses only one element, FD2, FD3, and
FD4 are programmed as zeroes, and FD1 is programmed
to the required data type.
●● If a configuration uses all four elements, FD1, FD2, FD3,
and FD4 are programmed to the required data types.
PPG data is left justified as shown in Table 3. In other
words, the MSB bit is always in the bit 18 position regardless of ADC resolution setting, and the LSBs are padded
with '0'. FIFO_DATA[23:19] are don't care and should be
masked.
●● If a configuration uses only two elements, FD3 and
FD4 are programmed as zeroes, and FD1 and FD2
are programmed to the required data types.
●● If a configuration uses only three elements, FD4 is
programmed as zeroes, and FD1, FD2, and FD3 are
programmed to the required data types.
ECG Data is right justified, FIFO_DATA[23:18]are always
padded with '0'.
Table 3. FIFO Data Format
FIFO_DATA
FIFO_DATA[0]
FIFO_DATA[1]
FIFO_DATA[2]
FIFO_DATA[3]
FIFO_DATA[4]
FIFO_DATA[5]
FIFO_DATA[6]
FIFO_DATA[7]
FIFO_DATA[8]
FIFO_DATA[9]
FIFO_DATA[10]
0
BYTE 3
FIFO_DATA[11]
x
0
FIFO_DATA[12]
x
0
FIFO_DATA[13]
FIFO_DATA[18]
x
0
FIFO_DATA[14]
FIFO_DATA[19]
x
0
FIFO_DATA[15]
FIFO_DATA[20]
x
0
FIFO_DATA[16]
FIFO_DATA[21]
PPG (19-bit)
ECG (18-bit)
FIFO_DATA[17]
ADC
Resolution
FIFO_DATA[22]
BYTE 2
FIFO_DATA[23]
BYTE 1
PPG elements are stored first, followed by ECG, as shown in the examples below:
Example 1: Configurations for 3 elements: PPG (LED 1) + PPG (LED2) + ECG
FD1[3:0]
FD2[3:0]
FD3[3:0]
FD4[3:0]
0001 (PPG)
0010 (PPG)
1001 (ECG)
0000 (None)
Example 2: Configurations for 2 elements: PPG (LED 2) + ECG
FD1[3:0]
FD2[3:0]
FD3[3:0]
FD4[3:0]
0010 (PPG)
1001 (ECG)
0000 (None)
0000 (None)
Example 3: Configurations for 2 elements: PPG (LED 1) + PPG (LED2)
FD1[3:0]
FD2[3:0]
FD3[3:0]
FD4[3:0]
0001 (PPG)
0010 (PPG)
0000 (None)
0000 (None)
Example 4: Configurations for 1 element: ECG
FD1[3:0]
FD2[3:0]
FD3[3:0]
FD4[3:0]
1001 (ECG)
0000 (None)
0000 (None)
0000 (None)
Example 5: Configurations for 1 element: PPG (LED 1)
FD1[3:0]
FD2[3:0]
FD3[3:0]
FD4[3:0]
0001 (PPG)
0000 (None)
0000 (None)
0000 (None)
www.maximintegrated.com
Maxim Integrated │ 41
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Table 4. Sample of FIFO Data Index
INDEX WITHIN A
SAMPLE
the samples. This allows rereading (or retrying) samples
from the FIFO.
FIFO_DATA[23:0]
0
FD1 data, if enabled
1
FD2 data, if enabled
2
FD3 data, if enabled
3
FD4 data, if enabled
FIFO Data Read, FIFO_DATA[7:0]:
This is a read-only register and is used to get data
from the FIFO. Reading FIFO_DATA register does not
automatically increment the register address. So burst
reading this register, reads the same address over and
over. The length of a sample is determined by the number
of active elements in the sample. Each element is three
bytes long. In order to read one complete sample the
FIFO_DATA register has to be read N times, where
A sample in the FIFO is shown in Table 4.
FIFO Handling
Only the elements corresponding to the active FIFO
data are pushed onto the FIFO, and only these are read
through the I2C. The unused FIFO data are not read
through the I2C, so they are don’t care and not padded
with zeroes.
The FIFO handling registers are shown in Table 5.
Write Pointer to the FIFO, FIFO_WR_PTR[4:0]:
This points to the location where the next sample will be
written. This pointer advances for each sample pushed
on to the FIFO.
Read Pointer to the FIFO, FIFO_RD_PTR[4:0]:
This points to the location from where the AP gets the
next sample from the FIFO through the I2C interface.
This advances each time a sample is popped from the
FIFO. The AP can also write to this pointer after reading
N = (Number of active elements) * (Number of bytes, 3)
Reading from the FIFO
Normally, reading registers from the I2C interface
autoincrements the register address pointer, so that all
the registers can be read in a burst read without an I2C
restart event. In this case, this holds true for all registers
except for the FIFO_DATA register (register 0x07).
Reading the FIFO_DATA register does not automatically
increment the register address. Burst reading this register
reads data from the same address over and over. Each
sample comprises multiple bytes of data, so multiple
bytes should be read from this register (in the same
transaction) to get one full sample.
FIFO_RD_PTR advances only after burst reading the
entire sample.
Table 5. FIFO Handling Registers
ADDRESS
REGISTER NAME
HARDWIRED
VALUE
0x04
FIFO Write Pointer
00
FIFO_WR_PTR[4:0]
0x05
Overflow Counter
00
OVF_COUNTER[4:0]
0x06
FIFO Read Pointer
00
0x07
FIFO Data Register
00
0x08
FIFO Configuration
00
www.maximintegrated.com
B7
B6
B5
B4
B3
B2
B1
B0
FIFO_RD_PTR[4:0]
FIFO_DATA[7:0]
A_FULL_
CLR
A_FULL_
TYPE
FIFO_ROLLS_ON_
FULL
FIFO_A_FULL[3:0]
Maxim Integrated │ 42
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Each sample is read from the FIFO in the following order, when all four Elements are active (Table 6).
Table 6. FIFO Sample Elements Order with four active elements
FIFO_RD_PTR[4:0]
n Sample:
n+1 Sample:
.
.
.
.
www.maximintegrated.com
1st read
Element 1[23:16]
n
2nd read
Element 1[15:8]
n
3rd read
Element 1[7:0]
n
4th read
Element 2[23:16]
n
5th read
Element 2[15:8]
n
6th read
Element 2[7:0]
n
7th read
Element 3[23:16]
n
8th read
Element 3[15:8]
n
9th read
Element 3[7:0]
n
10th read
Element 4[23:16]
n
11th read
Element 4[15:8]
n
12th read
Element 4[7:0]
n
13th read
Element 1[23:16]
n+1
14th read
Element 1[15:8]
n+1
15th read
Element 1[7:0]
n+1
16th read
Element 2[23:16]
n+1
17th read
Element 2[15:8]
n+1
18th read
Element 2[7:0]
n+1
19th read
Element 3[23:16]
n+1
20th read
Element 3[15:8]
n+1
21st read
Element 3[7:0]
n+1
22nd read
Element 4[23:16]
n+1
23rd read
Element 4[15:8]
n+1
24th read
Element 4[7:0]
n+1
.
.
.
.
.
.
.
.
.
.
.
.
Maxim Integrated │ 43
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Each sample is read from the FIFO in the following order, when any two Elements are active (Table 7).
Table 7. FIFO Sample Elements Order with two active elements
FIFO_RD_PTR[4:0]
n Sample:
n+1 Sample:
.
.
.
.
1st read
Element 1[23:16]
n
2nd read
Element 1[15:8]
n
3rd read
Element 1[7:0]
n
4th read
Element 2[23:16]
n
5th read
Element 2[15:8]
n
6th read
Element 2[7:0]
n
7th read
Element 1[23:16]
n+1
8th read
Element 1[15:8]
n+1
9th read
Element 1[7:0]
n+1
10th read
Element 2[23:16]
n+1
11th read
Element 2[15:8]
n+1
12th read
Element 2[7:0]
n+1
.
.
.
.
Enable Push on FIFO FULL, FIFO_ROLLS_ON_FULL:
This bit determines whether samples get pushed on to the
FIFO when it is full. If push is enabled when FIFO is full,
old samples are lost. Otherwise, new samples are lost.
Overflow counter, OVF_COUNTER[4:0]: When the FIFO
is full, samples are lost. OVF_COUNTER counts the
number of samples lost. It saturates at 0x1F. When a
complete sample is popped from the FIFO (when the read
pointer advances), and OVF_COUNTER is reset to zero.
FIFO Almost Full Counter, FIFO_AFULL_COUNT[3:0]:
This determines the amount of space available in the
FIFO, to declare that it is almost full.
FIFO Almost Full status, and Interrupt Enable, A_FULL
and MSK_A_FULL: When the FIFO is almost full, the
almost full interrupt is asserted if it is enabled by the
MSK_A_FULL bit. This prompts the AP to read some
samples before the FIFO gets full. A_FULL bit is cleared
when the status register is read.
The AP reads the FIFO_WR_PTR and FIFO_RD_PTR to
calculate the number of samples available in the FIFO,
and read as many samples as it needs up to a maximum
of available samples. The AP can then choose to write
the new read pointer to the FIFO_RD_PTR register. If
necessary to retry, the AP updates the FIF_RD_PTR
register with appropriate value.
www.maximintegrated.com
.
.
.
.
.
.
.
.
Example: Following is an example of the pseudo code:
First transaction: Get the FIFO_WR_PTR and FIFO_RD_
PTR:
START;
Send device address + write mode
Send address of FIFO_WR_PTR;
REPEATED_START;
Send device address + read mode
Read FIFO_WR_PTR;
Read OVF_COUNTER;
Read FIFO_RD_PTR;
STOP;
AP evaluates the number of samples to be read from the
FIFO:
If OVF_COUNTER is zero,
NUM_AVAILABLE_SAMPLES = FIFO_WR_PTR –
FIFO_RD_PTR
(Note: pointer wrap around should be taken into
account)
If OVF_COUNTER is non-zero some samples are
lost, and
NUM_AVAILABLE_SAMPLES = 32
NUM_SAMPLES_TO_READ = < less than or equal
to NUM_AVAILABLE_SAMPLES >
Maxim Integrated │ 44
MAX86150
Next transaction: Read NUM_SAMPLES_TO_READ
samples from the FIFO:
START;
Send device address + write mode
Send address of FIFO_DATA;
REPEATED_START;
Send device address + read mode
for (i = 0; i < NUM_SAMPLES_TO_READ; i++) {
Read FIFO_DATA;
Save Data_Item1[23:16];
Read FIFO_DATA;
Save Data_Item1[15:8];
Read FIFO_DATA;
Save Data_Item1[7:0];
Read FIFO_DATA;
Save Data_Item2[23:16];
Read FIFO_DATA;
Save Data_Item2[15:8];
Read FIFO_DATA;
Save Data_Item2[7:0];
Read FIFO_DATA;
Save Data_Item3[23:16];
Read FIFO_DATA;
Save Data_Item3[15:8];
Read FIFO_DATA;
Save Data_Item3[7:0];
}
STOP;
Next transaction: Write to FIFO_RD_PTR register. If the
pervious transaction was successful, FIFO_RD_PTR
points to the next sample in the FIFO, and this transaction
is not necessary. Otherwise, the AP updates the FIFO_
RD_PTR appropriately to New_FIFO_RD_PTR, so that
the samples are reread.
www.maximintegrated.com
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
START;
Send device address + write mode
Send address of FIFO_RD_PTR;
Write New_FIFO_RD_PTR;
STOP;
FIFO Flush
The FIFO gets flushed if FIFO_EN = 1, and if any of the
following conditions are met:
●● I2C write to any of the PPG Configuration registers
●● I2C write to any of the ECG Configuration registers
●● I2C write to any of the FIFO Data Control registers
●● At the rising edge of FIFO_EN
●● Enter and exit PROX mode
When the FIFO gets flushed, FIFO_WR_PTR and FIFO_
RD_PTR are reset to zero, and the contents of the FIFO
are lost.
If FIFO contents should not be lost, set FIFO_EN = 0,
before writing to any of the registers listed above.
Note: FIFO_EN bit is in the System Control register. Data
is pushed to the FIFO, when FIFO_EN = 1. When FIFO_
EN = 0, push to FIFO is disabled, but it holds the status of
the FIFO (FIFO pointers and the actual data).
FIFO Organization
Figure 9 shows how the samples are organized in the
FIFO when all four elements in a sample are active.
Figure 10 shows how the samples are organized in the
FIFO when only two elements in a sample are active.
Maxim Integrated │ 45
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
I2C BYTE 1
FIFO
POINTERS[4:0]
0x00
0x01
0x02
0x1F
I2C BYTE 2
I2C BYTE 3
23 ….……... 16, 15 ….….......... 8, 7 …...…....…. 0
RAM PHYSICAL
ADDRESS[6:0]
ELEMENT 1, SAMPLE N
0x00
ELEMENT 2, SAMPLE N
0x01
ELEMENT 3, SAMPLE N
0x02
ELEMENT 4, SAMPLE N
0x03
ELEMENT 1, SAMPLE N+1
0x04
ELEMENT 2, SAMPLE N+1
0x05
ELEMENT 3, SAMPLE N+1
0x06
ELEMENT 4, SAMPLE N+1
0x07
ELEMENT 1, SAMPLE N+2
0x08
ELEMENT 2, SAMPLE N+2
0x09
ELEMENT 3, SAMPLE N+2
0x0A
ELEMENT 4, SAMPLE N+2
0x0B
ELEMENT 1, SAMPLE N+31
0x7C
ELEMENT 2, SAMPLE N+31
0x7D
ELEMENT 3, SAMPLE N+31
0x7E
ELEMENT 4, SAMPLE N+31
0x7F
Figure 9. Example of FIFO Organization with Four Active Elements
www.maximintegrated.com
Maxim Integrated │ 46
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
I2C BYTE 1
FIFO
POINTERS[4:0]
0x00
0x01
0x02
0x1F
I2C BYTE 2
I2C BYTE 3
23 ….……... 16, 15 ….….......... 8, 7 …...…....…. 0
RAM PHYSICAL
ADDRESS[6:0]
ELEMENT 1, SAMPLE N
0x00
ELEMENT 2, SAMPLE N
0x01
NOT
USED
0x02
NOT
USED
0x03
ELEMENT 1, SAMPLE N+1
0x04
ELEMENT 2, SAMPLE N+1
0x05
NOT
USED
0x06
NOT
USED
0x07
ELEMENT 1, SAMPLE N+2
0x08
ELEMENT 2, SAMPLE N+2
0x09
NOT
USED
0x0A
NOT
USED
0x0B
ELEMENT 1, SAMPLE N+31
0x7C
ELEMENT 2, SAMPLE N+31
0x7D
NOT
USED
0x7E
NOT
USED
0x7F
Figure 10. Example of FIFO Organization with Two Active Elements
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
NC
Typical Application Circuit
NC
NC
50kΩ
Note 1
10pF
50kΩ
NC
ECG _N
ECG _P
10pF
NC
INTB
SDA
HOST PROCESSOR
SCL
22
21
2
20
3
19
4
18
5
6
MAX86150
17
16
7
15
8
14
9
13
10
11
12
C1_P
C1_N
1μF
VREF
GND _ANA
1μF
GND _DIG
PGND
VLED
3.3V
VDD _ANA
1.8V
VDD _DIG
NC
NC
1kΩ note 2
1kΩ note 2
1kΩ note 2
NC
1
D1.8V
0.1μF 10μF
0.1μF
4.7μF
PGND
0.1μF
GND_ANA
4.7μF
GND _DIG
VDDIO note 5
Note 3
D1.8V
Note 1: The RC Circuits added to the ECG_P and ECG_N are for Current Limiting and RF/EMI filtering purposes.
It’s value are system dependent.
.
Note 2: The value of I 2C and INTB pull up resistors should be based on the system design
Note 3: We suggest dedicated 1.8V for VDD _ANA whenever possible, otherwise VDD_ANA is suggested to be
isolated from other supplies, such as VDD_DIG.
Note 4: Use common design practice to isolate noise coupling between GND planes
.
Note 5: VDDIO is the system I/O voltage supply.
1.8V
0
0
Note 4
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX86150EFF+T
-40°C to +85°C
22-Lead OESIP
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape-and-reel.
www.maximintegrated.com
Maxim Integrated │ 48
MAX86150
Integrated Photoplethysmogram and
Electrocardiogram Bio-Sensor Module For
Mobile Health
Revision History
REVISION
NUMBER
REVISION
DATE
0
12/15
Initial release
1
11/16
General updates and typo corrections
12/18
Updated the General Description, Benefits and Features, Absolute Maximum Ratings,
Package Information, Electrical Characteristics, Pin Description, Detailed Description,
LED Driver, and Electrocardiogram (ECG) sections; updated the Register Map and
Interrupt Enable 1 (0x02), FIFO Data Control Register 1 (0x09), PPG Configuration
(0x0E), Prox Interrupt threshold (0x10), LED Pilot PA (0x15), and ECG Configuration
(0x3C) register tables; replaced all Typical Operating Characteristics; added ECG and
PPG Synchronization section
2
PAGES
CHANGED
DESCRIPTION
—
1–47
1–13, 15–20
22, 27, 30, 31
32, 34–35
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
© 2018 Maxim Integrated Products, Inc. │ 49
工商网监
湘ICP备2023018690号
