Renesas Launches the 32-bit RX23E-B, a Microcontroller with Integrated Analog Front-End

Renesas Electronics has announced the launch of a new 32-bit microcontroller in its RX family, this time bringing with it a high-precision analog front-end (AFE) — offering 24-bit resolution at up to eight times the speed of its predecessor.

"With the addition of the RX23E-B which comes with an AFE sensor interface, we can now serve a broad range of sensing applications from mid- to high-end systems," claims Sakae Ito, vice president of Renesas' Internet of Things Platform Business Division, of the new part. "We will continue to extend our product options to meet the growing needs of battery-powered and wireless sensors that demand low power consumption."

The stand-out feature of the RX23E-B is its analog front-end (AFE), a 24-bit delta-sigma analog-to-digital converter (ADC) which delivers a claimed sampling rate of 125 thousand samples per second (125kS/s) — an eightfold improvement on the company's earlier RX23E-B, Renesas says, with a 31.25kS/s variant available offering a reduced power draw. It's also less susceptible to noise at low voltage levels, the company claims, delivering root-mean square (RMS) noise of 0.18µVrms at 1kS/s — a third of the RX23E-A.

In addition to the AFE, the chip includes a single 32-bit RXv2 processor core running at up to 32MHz and including instructions for accelerating digital signal processing (DSP) workloads and floating-point arithmetic, 32kB of static RAM (SRAM), 256kB of flash memory plus 8kB for background data storage, a 16-bit digital-to-analog converter (ADC), a 12-bit eight-channel analog-to-digital converter (ADC), seven UART, one SPI, one I2C, and one CAN bus, a 40-segment LCDC interface for an LCD display, a watchdog timer, 16-bit six-channel PWM timers, eight-bit four-channel and 16-bit two-channel general-purpose timers, a low-power timer, and a real-time clock (RTC).

To prove its capabilities, Renesas has designed a reference implementation for the RX23E-B in a pressure control system — using the floating-point unit on the chip to accelerate filter calculations and proportional–integral–derivative (PID) control calculations, while combining it with a low drop-out (LDO) regulator and two "Intelligent Power Device" electronic relays to control solenoid valves in the system.

The RX23E-B is available to order now, price on application, on the Renesas website; the company has also launched a "Solution Starter Kit" for code-free evaluation and testing.