VitalSense – Part 3 : Alternatives for Heart Rate, SpO₂, and Temperature Sensing

Top Alternatives to the MAXREFDES117# for Heart Rate & SpO2 Sensing

Designing wearable devices or health-monitoring prototypes often starts with photoplethysmography (PPG)—the optical measurement of blood volume changes to detect heart rate (HR) and blood oxygen saturation (SpO2).

For years, the Analog Devices / Maxim Integrated MAXREFDES117# Reference Design Board has been a go-to benchmark for engineers and makers. Measuring a tiny 12.7 × 12.7 mm with pads designed for wearable integration (and even sewing into textiles with conductive thread), it packs the MAX30102 sensor, onboard power regulation, and I2C level shifting into an ultra-compact package.

However, depending on whether you are building a commercial wearable, setting up a rapid prototype, or looking for medical-grade precision, several strong alternatives exist on the market.

Here is a comprehensive breakdown of the top competing solutions and alternatives to the MAXREFDES117#.

1. Direct Drop-In Hardware Alternatives (MAX30102-Based)

If your firmware is already written for the MAX30102 chip and you simply need a different physical form factor or easier prototyping options, these modules keep the same underlying silicon.

MikroElektronika Oximeter 5 Click

    Core Sensor: MAX30102

    Form Factor: mikroBUS Click board (42.9 × 25.4 mm)

    Key Advantage: Breadboard-free hardware integration and ready-to-use software support.

While the MAXREFDES117# focuses on wearable miniaturization, MIKROE’s Oximeter 5 Click targets rapid benchtop evaluation. It interfaces seamlessly via the standardized mikroBUSTm header, features onboard voltage translation for 3.3V and 5V microcontrollers, and integrates directly with MIKROE's mikroSDK software ecosystem.

Generic MAX30102 Breakout Boards (e.g., Waveshare, Generic PCBs)

    Core Sensor: MAX30102

    Form Factor: Standard 2.54 mm (0.1") header PCB

    Key Advantage: Cost-effective and breadboard-friendly.

Generic breakout boards sacrifice the ultra-compact round design and textile-friendly pads of the MAXREFDES117# in favor of standard goldpin headers. They are significantly less expensive and ideal for early-stage proof-of-concept testing on breadboards or Arduino-based setups.

2. Upgraded Sensor Hubs & Enhanced Maxim/ADI Modules

Moving beyond raw sensor outputs, these alternatives offer updated optical hardware or onboard processing to handle the heavy computational math for you.

SparkFun Pulse Oximeter & Heart Rate Sensor (SEN-15219)

    Core Sensor: MAX30101 + MAX32664 Biometric Sensor Hub

    Form Factor: Qwiic-compatible breakout board

    Key Advantage: Onboard digital signal processing (DSP) and motion artifact filtering.

The biggest limitation of the MAXREFDES117# is that your main host MCU (e.g., STM32, ESP32, or AVR) must execute complex algorithms to extract clean HR and SpO2 values from noisy raw PPG data.

SparkFun solves this by combining the upgraded MAX30101 sensor (which adds a green LED alongside red and IR for better wrist-tracking stability) with the MAX32664 Sensor Hub. This onboard co-processor runs proprietary firmware that filters out motion noise in real time and calculates heart rate, SpO2, and signal quality—delivering ready-to-use digital values directly over I2C.

SparkFun Particle Sensor Breakout (MAX30105)

    Core Sensor: MAX30105

    Form Factor: Standard SparkFun breakout / Qwiic

    Key Advantage: Multi-purpose optical sensing (PPG + particle/smoke detection).

Equipped with red, IR, and green LEDs, the MAX30105 offers register-level compatibility with PPG measurement routines while expanding versatility to include ambient particle detection (smoke/dust) and optical proximity sensing.

3. Alternative Silicon Vendors (TI, AMS Osram, Silicon Labs)

If you are developing a custom PCB from scratch and want to evaluate IC alternatives outside the Analog Devices / Maxim ecosystem, consider these industry-leading silicon alternatives:

Solution / Board	Manufacturer	Image	Key Features & Target Application
EVM-AFE4404	Texas Instruments		Medical-Grade Precision: Highly flexible Analog Front-End (AFE) providing superior noise rejection, dynamic ambient light cancellation, and ultra-precise LED driver control. Ideal for clinical-grade devices.
AS7050 / AS7038	AMS Osram		Multi-Parametric Biosensing: Supports simultaneous PPG (heart rate & SpO2), ECG (electrocardiogram), and EDA (galvanic skin response/stress monitoring) on a single integrated solution.
Si117x / Si118x	Silicon Labs		Ultra-Low Power Wearables: Engineered specifically for wrist-based wearables, featuring built-in low-power algorithms optimized for long battery life in smartwatches and fitness trackers.

Alternatives to the MAX30208EVSYS Evaluation System

The MAX30208EVSYS is a professional evaluation system from Analog Devices (formerly Maxim Integrated) designed to test the MAX30208—an ultra-high accuracy (+/- 0.1'C in the medical range of 30'C to 50'C) digital temperature sensor. The system includes a microcontroller motherboard (MAX32630FTHR) and a flex PCB extension housing the sensor, allowing developers to easily attach it to human skin or conduct thermal flow analysis in wearable designs.

When evaluating alternatives to the MAX30208EVSYS, two distinct aspects should be considered: alternative evaluation boards/kits and alternative medical-grade (+/-0.1'C) temperature sensor ICs.

1. Alternative Development Kits & Evaluation Boards

If you are looking for a complete kit or breakout board to prototype body temperature sensing:

MikroElektronika Thermo 22 Click / MIKROE Temp Sensors

    Design: mikroBUS  form-factor expansion boards featuring integrated high-precision temperature sensors.

    Advantage over EVSYS: Instead of using a proprietary evaluation system with the MAX32630FTHR board, MIKROE Click boards plug directly into any standard host board (STM32 Nucleo, ESP32, Raspberry Pi) via the universal mikroBUS  socket. They come supported by turnkey mikroSDK software libraries.

Texas Instruments TMP117EVM (Evaluation Module)

    Main Sensor: TI TMP117 (+/- 0.1'C accuracy from -20'C to +50'C).

    Overview: Texas Instruments' official evaluation board featuring a detachable sensor breakout section.

    Advantage over EVSYS: The TI EVM provides a USB interface with a ready-to-use PC GUI and EEPROM emulation. The detachable breakout section is tiny and has low thermal mass, making it easy to integrate into wearable medical patch prototypes.

SparkFun / Adafruit High-Precision Temp Breakouts (e.g., PCT2075 / TMP117)

    Overview: Low-cost i2c breakout boards with Qwiic / STEMMA QT connectors.

    Advantage over EVSYS: The MAX30208EVSYS is relatively costly and geared toward industrial/medical evaluations. Adafruit/SparkFun breakout boards cost a fraction of the price and offer plug-and-play compatibility with Arduino and CircuitPython environments.

2. Alternative Silicon ICs (Medical-Grade Temperature Sensors)

If you are designing a custom PCB from scratch and need an alternative to the MAX30208 sensor chip itself: