Spezifikationen
MAX31865ATP+T is a high-precision platinum RTD-to-digital conversion IC from Analog Devices (Maxim Integrated). The suffix +T represents tape-and-reel surface-mount packaging for mass automated SMT production. It integrates a complete signal conditioning chain and Δ-Σ ADC, specially designed for PT100/PT1000 platinum thermal resistance temperature measurement in industrial precision control systemsAnalog Devices.
👉 It differs from thermocouple chips like MAX6675 and low-precision analog RTD frontends. This chip supports 2/3/4-wire RTD wiring with built-in lead resistance compensation, ±45V input overvoltage protection and full fault diagnosis, eliminating external op-amps and filter circuits to simplify high-accuracy temperature acquisition hardware design.
Wesentliche Merkmale
- Platinum RTD Full Support & High Measurement Precision
- Compatible with PT100 (100Ω@0℃) ~ PT1000 (1kΩ@0℃) platinum thermal resistors
- Supports 2-wire, 3-wire and 4-wire sensor wiring; 3/4-wire modes automatically offset cable resistance error
- 15-bit delta-sigma ADC, temperature resolution up to 0.03125℃; full-temperature total error ≤ ±0.5℃
- Fully differential reference input architecture to suppress common-mode industrial interference
- Maximum single conversion time only 21ms for fast real-time temperature sampling
- Robust Input Protection & Comprehensive Fault Detection
- All analog sensing pins withstand ±45V transient overvoltage, resisting EMC surges from long field wiring
- Programmable multi-type fault flag detection: RTD open circuit, RTD short circuit, short to power/GND
- Dedicated fault status bit output via SPI for MCU rapid abnormal temperature alarm judgment
- Standard SPI Serial Communication
- 4-wire SPI compatible interface (SCLK, SDO, SDI, CS#), works seamlessly with 3.3V industrial MCUs (GD32, STM32, FPGA)
- Read/write register architecture, directly output resistance ratio values for host to convert real temperature
- Daisy-chain multi-chip expansion supported for multi-point temperature monitoring boards
- Electrical Operating Characteristics
- Supply voltage VDD: 3.0V ~ 3.6V, matching mainstream single lithium and industrial 3.3V power rails
- Low quiescent operating current, minimal power consumption for battery-powered portable instruments
- Built-in precise RTD excitation constant current source, stable under wide temperature fluctuation
- Gehäuse- und Umgebungsbeständigkeit
- Package: 20-pin compact TQFN with exposed thermal pad (4mm × 4mm small footprint)
- Operating temperature range: -40℃ ~ +125℃ industrial wide temperature grade
- MSL 1 unlimited floor life, no dry bag storage requirement
- Fully RoHS lead-free, halogen-free and SVHC compliant; +T suffix tape-and-reel bulk packaging
Typische Anwendungen
Industrial furnace, oven, kiln high-precision multi-point temperature monitoring
Reflow oven, wave soldering equipment thermal curve acquisition modules
New energy lithium battery pack PT100 temperature sampling boards
CNC machine tool spindle, hydraulic oil temperature closed-loop control
Laboratory precision constant-temperature test chambers and aging equipment
Medical diagnostic equipment high-stability temperature measurement frontends
HVAC industrial heat treatment pipeline distributed temperature sensors
Agricultural machinery and off-highway equipment engine thermal monitoring
Portable industrial handheld temperature calibrators and data loggers
Embedded PLC remote IO temperature expansion modules
LXB Semicon supplies original Analog Devices MAX31865ATP+T PT100/PT1000 RTD digital converter IC







