Microcontrollers for Industrial Sensing and Measurement

Date
05/28/2019

 PDF
Delivers Better-than 0.1% Precision Performance in Temperature, Pressure, and Other Measurements

TOKYO, Japan - Renesas Electronics Corporation introduced the RX23E-A Group 32-bit RX microcontrollers (MCUs), combining high-precision analog front end (AFE) and an MCU on a single chip. Designed for manufacturing and test and measurement equipment applications that require high-precision measurements of analog signals for temperature, pressure, weight, and flow, the RX23E-A MCUs are the first Renesas solutions to enable such signals to be measured with better than 0.1% precision without calibration.

The new MCUs achieve AFE precision at the highest class in the industry (offset drift: 10 nV/°C, gain drift: 1 ppm/°C, and RMS noise: 30 nV rms), a level that could previously only be achieved by combining dedicated A/D converter circuits with high-precision operational amplifier ICs. By integrating this high-precision AFE IP (intellectual property) on a single chip using the same fabrication process technology, Renesas has made it possible to implement high-precision sensor measurement, computation, control, and communications on a single chip. This allows system manufactures to reduce the number of required components, save space, and simplify system design in a wide range of equipment requiring high-precision measurement, such as sensing, temperature controllers, recording, weighing, and force sensing. It also accelerates endpoint intelligence by enabling distributed processing with MCUs.

With big data-driven quality and productivity improvements, the pressure is on for factories and manufacturing sites to measure a wide variety of sensor data accurately and reliably. Since users require stability when measuring small signals at high precision over a wide environmental temperature range, it is important to reduce noise characteristics and temperature drift characteristics to low levels. To address these needs, Renesas has developed a high-precision AFE and integrated it into an RX MCU with an extensive track record with industrial applications.

The RX23E-A MCUs are based on the RXv2 core, which features operating speeds of 32 MHz, a digital signal processor (DSP), and superlative floating point unit (FPU) calculations. This allows the implementation of adaptive control using temperature data and inverse matrix calculations using 6-axis distortion data. For example, robot arm force sensors require the measurement and calculation of the 6-axis distortion in a small space. The RX23E-A MCUs make it possible to measure the 6-axis distortion data and perform the inverse matrix calculations with a single chip.

Key features of the RX23E-A MCUs

·           AFE block

-            24-bit delta-sigma A/D converter: Up to 23 bits of effective resolution. Data output rate flexible at 7.6 PS to 15.6 kPS.

-            Two 24-bit delta-sigma A/D converters that can start synchronously, allowing sensor temperature correction to be performed without switching channels.

-            PGA (programmable gain amplifier): Rail-to-rail input PGA allows amplification up to 128×. Offset drift: 10 nV/°C, gain drift: 1 ppm/°C, and RMS noise: 30 nV rms.

-            Voltage reference: Low temperature drift characteristics of 4 ppm/°C with superlative temperature stabilization.

-            Excitation current source: Programmable current source with required matching required for 3-wire resistance temperature detector.

-            Analog inputs: differential inputs: up to 6 channels, pseudo-differential inputs: up to 11 channels, single-ended inputs: up to 11 channels. All can be used as inputs to the two A/D converters.

·           MCU block

-            CPU: 32-bit RXv2 core operating at 32 MHz

-            Digital signal processing can be implemented with DPS instructions and FPU.

-            ROM/RAM: ROM: 128 to 256 KB, RAM: 16 to 32 KB.

-            Communication interfaces: SPI (1 channel), UART (4 channels), I2C (1 channel), CAN (1 channel).

-            Functional safety: software load reduced by Self-diagnostic and disconnection-detection assistance functions for the A/D converter, clock frequency accuracy measurement circuit, independent watchdog timer, RAM test assistance functions using the DOC and other circuits.

·           Supply voltage: 5V. Independent power supplies can be used for the AFE block and microcontroller. Voltages of 1.8 to 5.5 V can be supported.

·           Operating temperature: -40°C to +85°C, -40°C to +105°C

·           Package: 48-pin QFP with 7 mm square. 40-pin QFP with 6 mm square.

Availability

Samples of the RX23E-A Group of MCUs are available now with mass production planned for December 2019. (Availability are subject to change without notice.)

More Information

To learn more about the new Renesas RX23E-A MCUs, visit https://www.renesas.com/products/microcontrollers-microprocessors/rx/rx200/rx23e-a.html

RELATED

 



-->