ACS712
15Pages

ACS712 Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor Features and Benefits 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, switchmode power supplies, and overcurrent fault protection. The device is not intended for automotive applications. 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 TA = 25°C Small footprint, low-profile SOIC8 package 1.2 mΩ internal conductor resistance 2.1 kVRMS 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 The device consists of a precise, low-offset, linear Hall 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 the Hall IC converts 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 (>VIOUT(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 sampling. 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 Package: 8 Lead SOIC (suffix LC) Continued on the next page… Application 1. The ACS712 outputs an analog signal, VOUT . that varies linearly with the uni- or bi-directional AC or DC primary sampled current, IP , within the range specified. CF is recommended for noise management, with values that depend on the application. ACS712-DS, Rev. 15

Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor Description (continued) the device at up to 5× overcurrent conditions. The terminals of the conductive path are electrically isolated from the signal leads (pins 5 through 8). This allows the ACS712 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...

Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor Functional Block Diagram +5 V VCC (Pin 8) Hall Current Drive Sense Temperature Coefficient Trim Dynamic Offset Cancellation Signal Recovery Sense Trim 0 Ampere Offset Adjust Terminal List Table Number Terminals for current being sampled; fused internally Terminals for current being sampled; fused internally Signal ground terminal Terminal for external capacitor that sets bandwidth Analog output signal Device power supply terminal Allegro MicroSystems, LLC 115...

Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor COMMON OPERATING CHARACTERISTICS1 over full range of TA , CF = 1 nF, and VCC = 5 V, unless otherwise specified Characteristic Test Conditions ELECTRICAL CHARACTERISTICS Supply Voltage Supply Current Output Capacitance Load Output Resistive Load Primary Conductor Resistance Rise Time Frequency Bandwidth IP = IP(max), TA = 25°C, COUT = open Over full range of IP Over full range of IP Output reaches 90% of steady-state level, TJ = 25°C, 20 A present on leadframe Zero...

Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor x05B PERFORMANCE CHARACTERISTICS1 TA = –40°C to 85°C, CF = 1 nF, and VCC = 5 V, unless otherwise specified Characteristic Optimized Accuracy Range Sensitivity Symbol Sens Zero Current Output Slope Sensitivity Slope Total Output Error2 Test Conditions Peak-to-peak, TA = 25°C, 185 mV/A programmed Sensitivity, CF = 47 nF, COUT = open, 2 kHz bandwidth ∆Sens ETOT Over full range of IP, TA = 25°C may be operated at higher primary current levels, IP, and ambient...

Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor Characteristic Performance IP = 5 A, unless otherwise specified Supply Current versus Supply Voltage 10.9 10.8 10.7 ICC (mA) Mean Supply Current versus Ambient Temperature Magnetic Offset versus Ambient Temperature Sensitivity versus Ambient Temperature Mean Total Output Error versus Ambient Temperature Output Voltage versus Sensed Current Sensitivity versus Sensed Current 0 A Output Voltage versus Ambient Temperature 0 A Output Voltage Current versus Ambient...

Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 2.1 kVRMS Isolation and a Low-Resistance Current Conductor Characteristic Performance IP = 20 A, unless otherwise specified Mean Supply Current versus Ambient Temperature Supply Current versus Supply Voltage 10.4 Magnetic Offset versus Ambient Temperature Mean Total Output Error versus Ambient Temperature Sensitivity versus Ambient Temperature 100.8 Nonlinearity versus Ambient Temperature Output Voltage versus Sensed Current 110.00 Sensitivity versus Sensed Current 0 A Output Voltage versus Ambient Temperature 0 A Output...