Ultra-Low-Power Arm Cortex-M4F with Precision Analog Front-End and HART for Industrial and Medical Sensors

The MAX32675C is a highly integrated, mixed-signal, ultra-low-power microcontroller for industrial applications and is especially suitable for 4-20mA loop-powered sensors and transmitters. It is based on an ultra-low-power Arm® Cortex®- M4 with floating point unit (FPU) and includes 384KB (376KB user) flash and 160KB of SRAM. Error correction coding (ECC), capable of single-error correction, double-error detection (SEC-DED), is implemented over the entire flash, SRAM, and cache to ensure ultra-reliable code execution for demanding applications.

An analog front-end (AFE) with an integrated, low-power HART modem enables the bidirectional transfer of digital data over a current loop with industrial sensors for configuration and diagnostics. The AFE also provides two 12-channel delta-sigma (Δ-Σ) ADCs with features and specifications optimized for precision sensor measurement. Each Δ-Σ ADC can digitize external analog signals as well as system temperature. A PGA with gains of 1x to128x precedes each ADC. ADC outputs can be optionally converted on the fly from integer to single-precision floating-point format. A 12-bit DAC is also included.

The device also provides robust security features, including an AES engine and persistent key storage.

APPLICATIONS

* 4-20mA Industrial Sensors and Transmitters

* Industrial Pressure, Temperature, Flow, and LevelSensors/Transmitters

* Medical Pressure, Temperature, and Flow Sensors

* Low-Power, High-Performance for Industrial Applications

* 12MHz Arm Cortex-M4 with FPU

* 384KB (376KB User) Flash Memory

* 160KB SRAM (128KB with ECC Enabled)

* Optionally Retained in Low-Power Modes

* ACTIVE Current (IDDACTS) ≤ 2.1mA at TA = +85°C

* Ideal for 4-20mA Current Sense Loops

* Startup Current Typical (IDDSTRT) of 1.02mA

* 375μA Full Memory Retention Current in BACKUP(IDDFBKUS)

* Smart Integration Reduces BOM, Cost, and PCB Size

* Integrated HART Modem

* Two Δ-Σ ADCs

* 12 Channels, Assignable to Either ADC

* Flexible Resolution and Sample Rates

* 24-Bits at up to 0.4ksps

* 12-Bit DAC

* Internal Reference