Analog Devices / Maxim Integrated MAX30131/-2/-4 Programmable Analog Front Ends
Analog Devices MAX30131/-2/-4 Programmable Analog Front Ends (AFEs) feature 1-, 2-, and 4-channel ultra-low-power programmable operation, ideal for electrochemical sensors. The AFEs provide biasing and the complete measurement path, including the analog-to-digital converters (ADCs). The flexibility of the MAX30131/MAX30132/ MAX30134 enables them to work with both two and three-terminal electrochemical sensors, supplying both DC measurement and electrochemical impedance spectroscopy (EIS) measurement capability. The devices include an internal temperature sensor and a programmable voltage reference to support external temperature monitoring. Furthermore, the AFEs have an external reference source to integrate voltage monitoring of bias and supply voltages for safety and compliance.
The Analog Devices MAX30131/MAX30132/MAX30134 operate over a 1.73V to 5.0V voltage range. Total current consumption can be as low as 5μA, depending on the configuration, measurement frequency, and number of sensors. Communication is via a 4-pin SPI serial interface plus a configurable interrupt pin and four configurable general-purpose input/ outputs (GPIOs) for direct control of internal functions.
The MAX30131/MAX30132/MAX30134 are housed in a 25-bump WLP package and perform over a 0°C to +70°C temperature range.
Features
- Multichannel operation
- Up to four independent DC channels
- One switchable EIS channel
- High accuracy and precision
- Up to four 12-bit voltage DACs
- Up to four 16-bit current ADCs
- Programmable 0.8pA to 30pA resolution
- One 16-Bit EIS ADC
- Programmable 0.014Hz to 27kHz sine wave drive
- 12-bit voltage system ADC
- 16-bit temperature sensor
- Programmable, 30ppm/°C voltage reference
- Autonomous modes with a 256-word configurable FIFO and programmable alarm
- Long battery life for 2- and 3-terminal sensors
- 3.5μA continuous bias supply current for a single 2- or 3-terminal sensor
- Add 0.25μA for each additional sensor
- Small size
- 25-bump WLP 2.93mm x 2.93mm
- Safety and compliance
- Monitor sensor bias voltages for compliance
- Monitor supply/battery voltage and temperature
- Simple and robust digital interface
- 8MHz 4-wire SPI interface
- Programmable interrupt
- Four programmable GPIOs
- IEC61000-4-2 ESD: ±15kV air, ±8kV contact on sensor pins
Applications
- Electrochemical sensors
- Continuous glucose monitors
- Sweat sensors
- Wearable devices
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