ACS715 Automotive Grade, Fully Integrated, Hall Effect-Based Linear Current Sensor with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current Conductor - ALLEGRO MICROSYSTEMS - #1

■ Low-noise analog signal path

■ Device bandwidth is set via the FILTER pin

■ 5 us output rise time in response to step input current

■ 80 kHz bandwidth

■ Total output error 1.5% typical at T_A = 25°C

■ Small footprint, low-profile SOIC8 package

■ 1.2 m£2 internal conductor resistance

■ 2.1 kVRMS minimum isolation voltage from pins 1-4 to pins 5-8

■ 5.0 V, single supply operation

■ 133 to 185 mV/A output sensitivity

■ Output voltage proportional to DC currents

■ Factory-trimmed for accuracy

■ Extremely stable output offset voltage

■ Nearly zero magnetic hysteresis

■ Ratiometric output from supply voltage

■ Operating temperature range, -40°C to 150°C

The Allegro® ACS715 provides economical and precise solutions for DC current sensing in automotive 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 consists of a precise, low-offset, linear Hall sensor circuit with a copper conduction path located near the surface ofthe 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 (>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 sensing. The internal resistance of this conductive path is 1.2 m£2 typical, providing low power loss. The thickness of the copper conductor allows survival

C

0.1 jjF

Application 1. The ACS715 outputs an analog signal, V_OUT . that varies linearly with the unidirectional DC primary sensed current, I_P , within the range specified. C_F is recommended for noise management, with values that depend on the application.

ACS715-DS