System on Chip, abbreviated as SoC’, indicates that the system is on the chip. All key modules are integrated on a chip, including MCU, analog IP, digital IP, and memory (or EMIF). It is usually customized or the standard product for certain usage. In the energy metering field, SoC usually integrates MCU, metering module, real-time clock module, Flash and RAM memory, LCD driver module, UART/SPI/I2C communication module, and GPIO module.
V9901 is a single-phase energy metering SoC
chip, featuring very low power consumption and high performance. It integrates
Analog Front-End (AFE), energy metering architecture, enhanced 8052 MCU core,
RTC, WDT, Flash memory, SRAM, and LCD driver. It can be used for the
single-phase multi-functional energy meter applications.
Optional power supply 3.3 V or 5 V, wide input range: 2.5 V to 5.5 V
Reference voltage: 1.185 V (Typical drift 10 ppm/°C), interrupt triggered by external capacitor leakage
Low power operation with power-saving modes
Supporting anti-tampering energy metering application
Package: 100-LQFP
Operating temperature: -40 °C ~ +85 °C
Storage temperature: -40 °C ~ +125 °C
Energy metering features:
Four independent oversampling Σ/Δ ADCs
One voltage channel
Two current channels, supporting shunt or CT for current sensing
One multifunctional channel for various signal measurements
High metering accuracy:
Exceeding requirements of IEC 62053-21:2003, IEC 62053-22:2003, and IEC 62053-23:2003
Less than 0.1% error on active energy metering over dynamic range of 5000:1
Less than 0.1% error on reactive energy metering over dynamic range of 3000:1
Less than 0.5% error on current/voltage RMS calculation over dynamic range of 1000:1
Two current inputs for active energy metering, or one current input for active and reactive energy metering
Programmable energy metering modes
Calibrating meters via software
CF pulse output and interrupt with configurable pulse width
Zero-crossing interrupt
Speeding current detection to lower power consumption
Programmable threshold for no-load detection
MCU and peripherals:
High performance 8-bit 8052 MCU core, with programmable operation frequency, up to 26 MHz/6.5 mips
Two additional comparator
Integrated oscillator, only one external 32768-Hz crystal is needed to generate crystal frequency
Crystal supervised: Internal RC oscillator as a replacement when crystal oscillator stops running
Integrated RTC and temperature sensor, digital crystal frequency compensation for calibration over temperature variation
128-KB Flash memory, ISP and IAP supported, with write protection and encryption function
8-KB extended SRAM memory
Up to five UART serial interfaces, one supporting IR communication
One GPSI (General-Purpose Serial Interface), I2C compliant
Up to 70 programmable GPIOs, with port interrupt
Up to 16 fast IOs
Up to 12 hardware timers
Various sleep/wakeup methods, configurable wakeup with/without reset
Independent Watch-Dog Timer (WDT)