1.Summary

RN821X is a low power, high performance, highly integrated, highly reliable single-phase SOC chip, in which an  32-bit ARM Cortex-M0 core is embedded, and this product is able to meet the growing  requirements for functions and  performance of single-phase smart meter.

2.Product Features

Fundamental Features

n Highly integrated: 32bit ARM Cortex-M0,Measurement module, Hardware temperature compensation (RTC), 

The controller of LCD,EEPROM;

n Wide voltage range: Voltage range of 2.8V~5.5V to ensure the measurement’s accuracy;

 Typical voltage range of CPU system is 2.2V ~ 5.5V;

 GPIO supports docking devices having different operating voltages.

n High performance: Typical CPU operating frequency is 3.6864MHz (Maximum up to 29.4912MHz);

n Low power: Typical power consumption is about 3.5mA during the single-phase Smart Meter normal operation;

 Power consumption is about 18uA when the system operates at 32KHz;

 Power consumption of the overall chip is about 10uA in sleep mode.

n High precision: The active energy accuracy is less than 0.1% over a dynamic range of 5000:1;

 Typical reference temperature coefficient through the measurement is 5ppm; 

 The second pulse error of RTC is less than ± 5ppm within -25 ℃ ~ 70 ℃ and the minimum calibration scale is 0.068ppm;

n Package Type: LQFP100

Processor-related

n ARM Cortex-M0 core;

n The maximum operating frequency is up to 29.4812Mhz, 3.6864MHz is recommended for the single-phase  smart meter applications;

n Maximum support 192Kbytes FLASH memory,100000 Programming Cycles, More than 20 years of data  retention;

n Maximum support 16Kbytes SRAM;

n Maximum support 32KbytesEEPROM,1000000 Programming Cycle, support for byte operation, more than 20  years of data retention;

n Single-cycle multiplier(32bit*32bit);

n System timer is embedded in the CM0;

n 2 DMA controllers;

n Support for external interrupts and other ways to wake up;

n Complete hardware and software for the integrated development environment is provided

Measure

n The active energy accuracy is less than 0.1% over a dynamic range of 5000:1;

n Typical reference temperature coefficient is 5ppm;

n Support Neutral Wire and Fire Wire dual-channel's active power, reactive power, apparent power and current  RMS simultaneously measuring;

n Support Neutral Wire and Fire Wire dual-channel's active energy, reactive energy and apparent energy 

simultaneously measuring;

n Measurement are provided for RMS voltage and frequency of voltage line;

n Providing calibration of sampling channel's gain and offset;

n Providing power factor;

RTC

n Hardware’s automatic temperature compensation, precision and power consumption meet the national standard;

n Temperature Sensor: Provide accurate temperature, temperature measurement accuracy is ± 1 ℃ in the range  of -25 ℃ ~ 70 ℃; Power consumption less than 2uA;

LCD

n Support 4*34,6*32,8*30;

n Support DMA automatic loop display without CPU operating;

n Charge pump provides LCD voltage, supporting clearly display over wide voltage range and the full temperature  range;

n Power consumption of automatic loop display is less than 20uA.

Other Peripherals

n High speed GPIO, supports interface of peripheral devices with different voltage;

n 10bit ADC: Temperature sensor / battery voltage detection / generic ADC time division multiplexing;

n Voltage detecting LVD: chip supply voltage detection; external voltage detection.

n Two comparator CMP1and CMP2: external voltage detection, among which the CMP2’s power consumption  is less than 1uA,supporting low power supply monitoring under power failure.

n Timer:2 32bit extended timer,2 RTC timer,1 CM0 embedded system timer;

n UART:5 at most, supports automatic baud rate, support infrared modulation, supports UART wake up;

n 7816 port:2

n I2C:1

n SPI:1

n Watchdog: Hardware watchdog;

n Button Interrupts: 2, pin multiplexing;

n External interrupts: 4, pin multiplexing;

Encryption

n Hardware true random number generator meets the U.S. NIST FIPS140-2 standard;

n AES128/192/256 hardware encryption meets the FIPS197 standards, supporting EBC / CBC / CTR / GCM /  GMAC mode;

n ECC192 hardware accelerators;

n Encryption documentation refers to Renergy application notes.

Card Meter Isolation

Provide high reliable and low cost card meter isolation solutions which can be seen in detail in Renergy RN8501 card  meter isolation scheme explains;