Dual-Channel, Platinum, RTD-to-Voltage Signal Conditioner

Replaces Expensive, Discrete Solutions while Reducing Board Space by Offering Complete Automotive Fault Protection Against ESD (±8kV Rated) and Short-to-Battery Fault, Plus Sensitive Microcontroller Inputs Protection


The MAX6603 dual-channel, platinum RTD-to-voltage signal conditioner excites and amplifies the signal from two external 200Ω platinum-resistive temperature devices (Pt RTD) to achieve high-voltage, level-filtered signals for temperature measurements. The MAX6603 provides a direct ratiometric output voltage to simplify the interface to microcontrollers with integrated analog-to-digital converters (ADCs). External precision resistors and calibration processes are not needed. The MAX6603 provides the necessary signal-conditioning functions, including ratiometric excitation current, amplification, buffered voltage outputs, diagnostic fault detections, and input protection. The MAX6603 amplifies signals from two RTDs operating over the -40°C to +1000°C temperature range and provides the temperature information as two independent analog voltages. The MAX6603 features a ±6°C (max) accuracy over the +400°C to +600°C temperature range.

The MAX6603 has overvoltage protection up to +16V on RTD inputs, and ±5kV electrostatic discharge (ESD) protection at RTD input pins for reliable operation where RTD temperature-sensing probes are used. The MAX6603 monitors the RTD for faults and asserts the respective active-low DG output low for fault conditions. The analog voltage outputs can be readily connected to a variety of microcontrollers.

The MAX6603 is available in a small, 10-pin TDFN-EP package and operates over the -40°C to +125°C automotive temperature range from a single +3V to +5.5V power supply.
MAX6603: Typical Operating Circuit MAX6603: Typical Operating Circuit Enlarge+

Key Features

  • Amplifies Pt RTD Temperature Signals
  • ±5kV ESD Protection on RTD Inputs
  • +16V Overvoltage Fault Protection on RTD Inputs
  • Low RTD Excitation Current Minimizes Self-Heating Errors
  • Small, 10-Pin TDFN Package
  • Fully Ratiometric Operation
  • No Calibration Required for Standard RTDs
  • RTD Diagnostic Check
  • High Accuracy: ±6°C (max) from +400°C to +600°C


  • Braking Systems
  • Engine Control Management to Meet EURO IV Regulations
  • Food Transportation Monitoring Systems
  • Industrial Process Measurements
  • Industrial Temperature Sensors

Technical Documents

Tutorial 4679 Thermal Management Handbook
Reference Schematic 4531 Reference Design for a PC-based Temperature-Measurement System

Quality and Environmental Data

Request Reliability Report for: MAX6603 
Lead-Free Package Tin (Sn) Whisker Reports

Additional Resources

Topmark Coding MAX6603

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