描述 Description

The Allegro ACS724MA current sensor IC is an economicaland precise solution for AC or DC current sensing in automotive, industrial,commercial, and communication systems. The small surface mount SOICW-16 MA packageis ideal for space-constrained applications while offering reinforced isolation. Typical applications include On-Board Chargers (OBC), DC/DC Converters, motor control, load detection and management, switched-modepower supplies, and overcurrent fault protection.

The automotive variant, ACS724LMA, is offered in the “L” temperature range (–40°C to 150°C) while the industrial variant, ACS724KMA, is offered in the “K” temperature range (–40°C to 125°C).

The device consists of a precise, low-offset, linear Hallsensor circuit with a copper conduction path located near thesurface of the die. Applied current flowing through this copperconduction path generates a magnetic field which is sensedby the integrated Hall IC and converted into a proportionalvoltage. The current is sensed differentially in order to rejectcommon-mode fields, improving accuracy in magneticallynoisy environments. The inherent device accuracy is optimizedthrough the close proximity of the magnetic field to the Halltransducer. A precise, proportional voltage is provided by thelow-offset, chopper-stabilized BiCMOS Hall IC, which includesAllegro’s patented digital temperature compensation, resultingin extremely accurate performance over temperature. The outputof the device has a positive slope when an increasing currentflows through the primary copper conduction path (from pins1 through 4, to pins 5 through 8), which is the path used forcurrent sensing. The internal resistance of this conductive pathis 0.85 mΩ typical, providing low power loss.

The terminals of the conductive path are electrically isolatedfrom the sensor leads (pins 9 through 16). This allows theACS724KMA current sensor IC to be used in high-side currentsense applications without the use of high-side differential amplifiersor other costly isolation techniques.

The ACS724MA is provided in a low-profile surface-mountSOICW-16 package. The leadframe is plated with 100% matte tin,which is compatible with standard lead (Pb) free printed circuit boardassembly processes. Internally, the device is Pb-free. The device isfully calibrated prior to shipment from the factory.

特性 Features

? Automotive Qualified per AEC-Q100 (“L” temperature variant only)
? Differential Hall sensing rejects common-mode fields
? Patented integrated digital temperature compensation?circuitry allows for near closed loop accuracy over?temperature in an open loop sensor
? UL60950-1 (ed. 2) certified
? Dielectric Strength Voltage = 4.8?kVRMS
? Basic Isolation Working Voltage = 1097?VRMS
? Reinforced Isolation Working Voltage = 565?VRMS

? Industry-leading noise performance with greatly improved?bandwidth through proprietary amplifier and filter design?techniques
? Filter pin allows user to filter output for improved?resolution at lower bandwidth
? 0.85 mΩ primary conductor resistance for low power loss?and high inrush current withstand capability
? Low-profile SOICW-16 package suitable for space-constrained?applications
? 4.5 to 5.5?V single supply operation
? Output voltage proportional to AC or DC current
? Factory-trimmed sensitivity and quiescent output voltage for?improved accuracy
? Chopper stabilization results in extremely stable quiescent?output voltage
? Nearly zero magnetic hysteresis
? Ratiometric output from supply voltage