Allegro® ACS712 可为工业、汽车、商业和通信系统中的交流或直流电流感测提供经济实惠的精密解决方案。该器件封装便于客户轻松实施。典型应用包括电动机控制、载荷检测和管理、开关式电源和过电流故障保护。

该器件具有精确的低偏置线性霍尔传感器电路，且其铜制的电流路径靠近晶片的表面。通过该铜制电流路径施加的电流能够生成可被集成霍尔 IC 感应并转化为成比例电压的磁场。通过将磁性信号靠近霍尔传感器，实现器件精确度优化。 精确的成比例电压由稳定斩波型低偏置 BiCMOS 霍尔 IC 提供，该 IC 出厂时已进行精确度编程。

当通过用作电流感测通路的主要铜制电流路径（从引脚 1 和 2，到 3 和 4）的电流不断上升时，器件的输出具有正斜率 (>V_IOUT(Q))。 该传导通路的内电阻通常是 1.2 mΩ，具有较低的功耗。铜线的粗细允许器件在可达 5× 的过电流条件下运行。传导通路的接线端与传感器引脚（引脚 5 到 8）是电气绝缘的。 这让 ACS712 电流传感器可用于那些要求电气绝缘却未使用光电绝缘器或其它昂贵绝缘技术的应用。

ACS712 采用小型的表面安装 SOIC8 封装。引脚架镀采用 100% 雾锡电镀，可与标准无铅 (Pb) 印刷电路板装配流程兼容。 在内部，该器件为无铅产品，倒装法使用当前豁免于 RoHS 的高温含铅焊球除外。器件在出厂装运前已完全校准。

ACS712
Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current Conductor

Features

• Low-noise analog signal path
• Device bandwidth is set via the new FILTER pin
• 5 µs output rise time in response to step input current
• 80 kHz bandwidth
• Total output error 1.5% at T_A = 25°C
• Small footprint, low-profile SOIC8 package
• 1.2 mΩ internal conductor resistance
• 2.1 kV_RMS minimum isolation voltage from pins 1-4 to pins 5-8
• 5.0 V, single supply operation
• 66 to 185 mV/A output sensitivity
• Output voltage proportional to AC or DC currents
• Factory-trimmed for accuracy
• Extremely stable output offset voltage
• Nearly zero magnetic hysteresis
• Ratiometric output from supply voltage

Description

The Allegro® ACS712 provides economical and precise solutions for AC or DC current sensing in industrial, commercial, and communications systems. The device package allows for easy implementation by the customer. Typical applications include motor control, load detection and management, switched-mode power supplies, and overcurrent fault protection. The device is not intended for automotive applications.

The device consists of a precise, low-offset, linear Hall sensor circuit with a copper conduction path located near the surface of the die. Applied current flowing through this copper conduction path generates a magnetic field which is sensed by the integrated Hall IC and converted into a proportional voltage. Device accuracy is optimized through the close proximity of the magnetic signal to the Hall transducer. A precise, proportional voltage is provided by the low-offset, chopper-stabilized BiCMOS Hall IC, which is programmed for accuracy after packaging.

The output of the device has a positive slope (>V_IOUT(Q)) when an increasing current flows through the primary copper conduction path (from pins 1 and 2, to pins 3 and 4), which is the path used for current sensing. The internal resistance of this conductive path is 1.2 mΩ typical, providing low power loss. The thickness of the copper conductor allows survival of the device at up to 5× overcurrent conditions. The terminals of the conductive path are electrically isolated from the sensor IC leads (pins 5 through 8). This allows the ACS712 current sensor IC to be used in applications requiring electrical isolation without the use of opto-isolators or other costly isolation techniques.

The ACS712 is provided in a small, surface mount SOIC8 package. The leadframe is plated with 100% matte tin, which is compatible with standard lead (Pb) free printed circuit board assembly processes. Internally, the device is Pb-free, except for flip-chip high-temperature Pb-based solder balls, currently exempt from RoHS. The device is fully calibrated prior to shipment from the factory.