Low-power microcontroller for analogue sensors

Microchip is aiming at analogue sensors with a microcontroller that can measure signals while consuming less than 3µA while sleeping with one comparator monitoring an in-coming voltage.

Microchip PIC16F17576 analogue sensor microcontroller

Called PIC16F17576, it has a power-saving ‘analogue peripheral manager’ (APM).

“The APM controls which peripherals are active to minimise total energy consumption and enable battery-operated applications,” according to the company.

Inside the APM is a 16bit timer with a 16bit prescaler that can be clocked using a variety of sources, including 31kHz, 32.768kHz, the ADC’s RC oscillator or an external signal.

With the CPU sleeping, this timer is used to periodically turn on and off the MCU’s peripherals including its 12bit differential ADC, low-power comparator, fast (50ns) comparator, dual 8bit DACs, four operational amplifiers and a voltage reference – each with its own timing (not all packages offer access to all resources).

For added flexibility, the op-amps have software-controlled gain ladders and the ADC has automated averaging.

The processor core runs up to 32MHz, and it supported by up to 28kbyte of programme flash, 2kbyte of ram and 256bytes of eeprom.

Among digital peripherals are 3x 8bit timers, 2x 16bit timers, 2x 16bit capture-compare-PWM blocks, 2x 16bit PWM generators and the company’s complimentary waveform generator for creating dc-dc converter drive signals.

More unusual peripherals include for configurable logic cells blocks and a numerically-controlled oscillator for generating arbitrary frequencies.

Peripherals can be connected together without using external package pins through a peripheral called the ‘signal routing port’.

For external communication, there are two enhanced UARTs which provide serial interfaces including RS-485, and two serial port that can be configured for SPI or I²C communication.

Operation is over 1.8 – 5.5V and -40 to +85°C or +125°C.

Typical 25°C power figures include: <600nA 3V sleep (+300nA to add the watchdog), 48µA running at 32kHz, and <1mA at 4MHz and 5V.

Applications are expected monitoring vibration, strain, motion, flow, gas and cold assets, in industry, homes and buildings.

The devices are compatible with the company’s EV14L29A development board.

Find Microchip’s product page here. The company introduced a microcontroller with a 32 LUT programmable logic block last week.