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

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.

Applications

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

* 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