原标题：ST STPM10和STM8L15xx MCU单相电表解决方案

　　ST公司的STEVAL-IPE012V2是采用SPM10和STM8L152C6 超低功耗MCU的单相电表评估板,支持IEC 61036:1996 + A1: 2000,是低本单相电表解决方案, 使用电压240V,典型电流10A,最大电流80A,电表适用频率45Hz到65Hz,动态范围200:1时的精度为1级,通信接口采用IrDA.本文介绍了评估板STEVAL-IPE012V2两个核心器件STPM10和STM8L15xx MCU主要特性,框图以及评估板STEVAL-IPE012V2主要特性和指标,电路图,材料清单和PCB元件布局图.

　　The STPM10 is designed for effective measurement of active, reactive and apparent energy in a power line system using current transformer and shunt sensors. The device can be implemented for peripheral measurement in a microcontroller-based single-phase or poly-phase energy meter. The STPM10 consists of two main sections: analog and digital. The analog part is composed of preamplifier and first-order sigmadelta A/D converter blocks, a band-gap voltage reference and low-drop voltage regulator. The digital part is composed of system control, oscillator, hard-wired DSP and SPI interface.

　　There is also an internal volatile memory, which is controlled through the SPI by means of a dedicated command set. The configured bits are used for configuration and calibration purposes.From a pair of sigma-delta output signals produced by the analog section, the DSP unit computes the amount of active, reactive and apparent energy consumed, as well as the RMS and instantaneous voltage and current values.

　　The results of the computation are available as pulse frequencies and states on the digital outputs of the device, or as data bits in a data stream, which can be read from the device by means of the SPI interface. The system bus interface is also used for temporary programming of bits of internal volatile memory. The STPM10 generates an output signal with a pulse frequency proportional to the energy, and this signal is used in the calibration phase of the energy metering application.

　　STPM10 主要特性:

　　■ Measures active, reactive, and apparent energies

　　■ Current, voltage RMS and instantaneous measurement

　　■ Frequency measurement

　　■ Ripple-free active energy pulsed output

　　■ Live and neutral monitoring for tamper detection

　　■ Fast and simple one-point digital calibration over the whole current range

　　■ Integrated linear voltage regulators for digital and analog supply

　　■ Selectable RC or crystal oscillator

　　■ Supports 50 - 60 Hz - IEC62052-11, IEC62053-2x specifications

　　■ Less than 0.1% error in the 1000:1 range

　　■ Precision voltage reference: 1.23 V with 30 ppm/°C max

　　图1. STPM10框图

　　图2. STPM10参考电路图

　　STM8L15xx超低功耗MCU

　　The high density and medium+ density STM8L15xx Ultralow power devices feature an enhanced STM8 CPU core providing increased processing power (up to 16 MIPS at 16 MHz) while maintaining the advantages of a CISC architecture with improved code density, a 24-bit linear addressing space and an optimized architecture for low power operations.

　　The family includes an integrated debug module with a hardware interface (SWIM) which allows non-intrusive in-application debugging and ultrafast Flash programming.

　　All high density and medium+ density STM8L15xx microcontrollers feature embedded data EEPROM and low power low-voltage single-supply program Flash memory.

　　The devices incorporate an extensive range of enhanced I/Os and peripherals, a 12-bit ADC, two DACs, two comparators, a real-time clock, four 16-bit timers, one 8-bit timer, as well as standard communication interfaces such as two SPIs, an I2C interface, and three USARTs. A 8x40 or 4x44-segment LCD is available on the STM8L152x8 devices. The modular design of the peripheral set allows the same peripherals to be found in different ST microcontroller families including 32-bit families. This makes any transition to a different family very easy, and simplified even more by the use of a common set of development tools.

　　High density and medium+ density STM8L15xx devices are part of the STM8L Ultralow power family providing the following benefits:

　　• Integrated system

　　– Up to 64 Kbytes of high-density embedded Flash program memory

　　– Up to 2 Kbytes of data EEPROM

　　– Up to 4 Kbytes of RAM

　　– Internal high-speed and low-power low speed RC.

　　– Embedded reset

　　• Ultralow power consumption

　　– 1 μA in Active-halt mode

　　– Clock gated system and optimized power management

　　– Capability to execute from RAM for Low power wait mode and Low power run mode

　　• Advanced features

　　– Up to 16 MIPS at 16 MHz CPU clock frequency

　　– Direct memory access (DMA) for memory-to-memory or peripheral-to-memory access.

　　• Short development cycles

　　– Application scalability across a common family product architecture with compatible pinout, memory map and modular peripherals.

　　– Wide choice of development tools

　　STM8L Ultralow power microcontrollers can operate either from 1.8 to 3.6 V (down to 1.65 V

　　at power-down) or from 1.65 to 3.6 V. They are available in the -40 to +85 ℃ and -40 to +125 ℃ temperature ranges.

　　These features make the STM8L Ultralow power microcontroller families suitable for a wide range of applications:

　　• Medical and handheld equipment

　　• Application control and user interface

　　• PC peripherals, gaming, GPS and sport equipment

　　• Alarm systems, wired and wireless sensors

　　• Metering

　　图3. STM8L15xx MCU框图

　　STM8L15xx 主要特性:

　　• Operating conditions

　　– Operating power supply: 1.65 to 3.6 V(without BOR), 1.8 to 3.6 V (with BOR)

　　– Temp. range: -40 to 85, 105 or 125 °C

　　• Low power features

　　– 5 low power modes: Wait, Low power run (5.9 μA), Low power wait (3 μA), Active-halt with full RTC (1.4 μA), Halt (400 nA)

　　– Consumption: 200 μA/MHz+330 μA

　　– Fast wake up from Halt mode (4.7 μs)

　　– Ultra low leakage per I/0: 50 nA

　　• Advanced STM8 core

　　– Harvard architecture and 3-stage pipeline

　　– Max freq: 16 MHz, 16 CISC MIPS peak

　　– Up to 40 external interrupt sources

　　• Reset and supply management

　　– Low power, ultrasafe BOR reset with 5 programmable thresholds

　　– Ultralow power POR/PDR

　　– Programmable voltage detector (PVD)

　　• Clock management

　　– 32 kHz and 1-16 MHz crystal oscillators

　　– Internal 16 MHz factory-trimmed RC and 38 kHz low consumption RC

　　– Clock security system

　　• Low power RTC

　　– BCD calendar with alarm interrupt,

　　– Digital calibration with +/- 0.5ppm accuracy

　　– Advanced anti-tamper detection

　　• DMA

　　– 4 ch. for ADC, DACs, SPIs, I2C, USARTs, Timers, 1 ch. for memory-to-memory

　　• LCD: 8x40 or 4x44 w/ step-up converter

　　• 12-bit ADC up to 1 Msps/28 channels

　　– Temp. sensor and internal ref. voltage

　　• Memories

　　– Up to 64 KB of Flash memory with up to 2 KB of data EEPROM with ECC and RWW

　　– Flexible write/read protection modes

　　– Up to 4 KB of RAM

　　• 2x12-bit DAC (dual mode) with output buffer

　　• 2 ultralow power comparators

　　– 1 with fixed threshold and 1 rail to rail

　　– Wakeup capability

　　• Timers

　　– Three 16-bit timers with 2 channels (IC, OC, PWM), quadrature encoder

　　– One 16-bit advanced control timer with 3 channels, supporting motor control

　　– One 8-bit timer with 7-bit prescaler

　　– 1 Window and 1 independent watchdog

　　– Beeper timer with 1, 2 or 4 kHz frequencies

　　• Communication interfaces

　　– Two synchronous serial interface (SPI)

　　– Fast I2C 400 kHz SMBus and PMBus

　　– Three USARTs (ISO 7816 interface + IrDA)

　　• Up to 67 I/Os, all mappable on interrupt vectors

　　• Up to 16 capacitive sensing channels supporting touchkey, proximity, linear touch and rotary touch sensors

　　• Fast on-chip programming and non-intrusive debugging with SWIM, Bootloader using

　　USART

　　• 96-bit unique ID

　　采用SPM10和STM8L152C6 MCU的单相电表评估板STEVAL-IPE012V2

　　This board can be connected to mains voltage (240 V). In the case of improper use, wrong

　　installation or malfunction, there is a danger of serious personal injury and damage to property. All operations such as transport, installation and commissioning, as well as maintenance, should be carried out only by skilled technical personnel (regional accident prevention rules must be observed).

　　This document describes the functions of a single-phase energy meter based on the STPM10 metering IC and STM8L152C6 microcontroller. The demonstration board solution is a fully functional single-phase solution with parameter display, tamper management, maximum demand (MD) calculation, EEPROM data logging and low-power management.

　　评估板STEVAL-IPE012V2主要特性:

　　● Low cost single-phase energy meter solution

　　● Supports IEC 61036:1996 + A1: 2000, static meter for active energy classes 1 for Ib =10 A

　　● Less than 4 VA power consumption for voltage circuit at reference voltage

　　● Less than 1 VA power consumption for current circuit at reference basic current

　　● Multiple tamper detection: earth, neutral missing, reverse, case tamper, magnetic tamper detection.

　　● Case tamper detection in power-down also

　　● Detects, signals and continues to measure accurately under tamper condition

　　● Rechargeable battery is available on board for showing LCD parameters in case of power down mode

　　● Active energy pulse output 1600 impulses/kWh

　　● Software based auto-calibration without the need of a reference meter, only a reference source is required

　　● Microcontroller built-in RTC for date and time display

　　● Microcontroller STM8L152C6T6 is responsible for all the data management, display and power management

　　● STPM10 metering IC with 1st order sigma-delta ADC for energy measurements

　　● Single point and fast calibration of the STPM10 for class 1 meter

　　● External EEPROM used to store calibration parameters, tampering information, cumulative energy, MD and power factor (PF) data

　　● Active power, current, voltage, power factor and line frequency measurements

　　● Numeric display precision (except cumulative energy): 5+2 digits

　　● Numeric display precision for cumulative energy: 5+1 digits

　　● Energy EEPROM log precision: 0.01 kWh.

　　评估板STEVAL-IPE012V2技术指标:

　　■ Accuracy: class 1 with dynamic range 200:1

　　■ Nominal voltage: 240 V

　　■ Nominal current: 10 A (ITYP)

　　■ Maximum current: 80 A (IMAX)

　　■ Operating range: 0.6 Vb to 1.2 Vb

　　■ Meter constant: 1600 impulses/KWh

　　■ Power frequency range: 45 Hz to 65 Hz

　　■ Sensor: primary side CT and secondary side shunt

　　■ Communication interface: IrDA

　　图4. 评估板STEVAL-IPE012V2外形图

　　图5. 评估板STEVAL-IPE012V2电路图(1)

　　图6. 评估板STEVAL-IPE012V2电路图(2)

　　评估板STEVAL-IPE012V2材料清单(BOM):