Allegro公司的ACS71020電源監視集成電路，采用霍爾效應電流絕緣的電流傳感器技術，大大地簡化了任何AC/DC電源設備的功率監測。用戶可編程VRMS欠壓/過壓引腳，1kHz帶寬，電流檢測從0A到90A，I2C或SPI通信，通過EEPROM寄存器進行用戶編程，16位電壓和電流ADC.本文介紹了ACS71020主要特性，框圖和典型應用電路圖以及ACS71020演示板主要元件和電路圖。

The ACS71020 power monitoring IC greatly simplifies the addition of power monitoring to any AC/DC powered device. By making use of Allegro’s Hall-effect-based， galvanically isolated integrated current sensor technology， reinforced isolation can be achieved. The sensor can be powered from the same supply as the MCU， eliminating the need for multiple power supplies and digital isolation ICs.

The isolated current measurement is done by detecting the magnetic field from the integrated conductor， eliminating the need for external sense resistors， current transformers， or Rogowski coils. Two Hall plates are used for this measurement to differentially sense the field， thus eliminating errors due to stray magnetic fields. Multiple parameters like bandwidth， averaging time， and fault levels are user-programmable.

The sensor features all key power measurements， which can be read out through I2C or SPI， as well as dedicated pins for voltage zero crossing （suitable for light-dimming applications） and fast overcurrent fault （for short-circuit detection）。 As the sensor is isolated， these pins can be easily accessed by the MCU without additional isolation to each signal. These two pins can also be configured to flag a VRMS under/overvoltage.

The ACS71020 is provided in a small， low-profile， surface-mount SOIC16 wide-body package. The ACS71020 is lead （Pb） free， and is fully calibrated prior to shipment from the factory. Further customer calibration in application can improve accuracy.

ACS71020主要特性：

Accurate power monitoring of AC/DC applications

Reinforced isolation up to 517 VRMS in a single package eliminates the need for dual isolated supplies （certification pending）

Active， reactive， and apparent power measurements， and power factor

RMS and instantaneous voltage and current measurements

0.85 mΩ primary conductor resistance for low power loss and high inrush current withstand capability

Dedicated voltage zero crossing pin

Overcurrent fault output pin

Hall-effect-based current measurement with common-mode stray field rejection

User-programmable VRMS under/overvoltage pin

1 kHz bandwidth

Current-sensing range from 0 to 90 A

I2C or SPI communication

User-programmable through EEPROM registers

16-bit voltage and current ADCs

圖1.ACS71020框圖

圖2. ACS71020典型應用電路圖

ACS71020演示板

Allegro ACS71020 demo board is pictured in Figure 2 below. Refer to Table 1 for symbol names and descriptions of onboard components. Note： Board is pictured without capacitors and resistors attached.

圖3.ACS71020電流傳感器演示板外形圖

ACS71020電流傳感器演示板元件表：

圖4. ACS71020電流傳感器演示板電路圖

詳情請見：

https://www.allegromicro.com/en/Products/Current-Sensor-ICs/Zero-To-Fifty-Amp-Integrated-Conductor-Sensor-ICs/ACS71020.aspx

ACS71020-Datasheet.pdf

ASEK71020-Eval-Board-User-Manual.pdf