A1357 Datasheet | Allegro MicroSystems

FEATURES AND BENEFITS - Two-wire output enables reduced wiring costs in long wire systems - Simultaneous programming of PWM carrier frequency, quiescent duty cycle (QDC), and sensitivity for system optimization - Fully differential signal path increases EMC immunity and reduces output offset drifts - Factory-programmed sensitivity temperature coefficient and quiescent duty cycle drift - Programmability at end-of-line - Pulse width modulated (PWM) current output provides increased noise and EMC immunity pared to an analog output - Precise recoverability after temperature cycling - Duty cycle clamps provide short circuit diagnostic capabilities - Optional 50% duty cycle calibration test mode at device power up - Wide ambient temperature range: - 40°C to 150°C - Resistant to mechanical stress PACKAGE: 3-pin SIP (suffix KB) DESCRIPTION The A1357 device is a high precision, programmable two-wire Hall-effect linear sensor IC with a pulse width modulated (PWM) current. The A1357 device converts an analog signal from its internal Hall sensor element to a digitally encoded PWM signal. The coupled noise immunity of the digitally encoded PWM is far superior to the noise immunity of an analog output signal. The Bi CMOS, monolithic circuit inside of the A1357 integrates a Hall element, precision temperature-pensating circuitry to reduce the intrinsic sensitivity and offset drift of the Hall element, a small-signal high-gain amplifier, proprietary dynamic offset cancellation circuits, and PWM conversion circuitry. The dynamic offset cancellation circuits reduce the residual offset voltage of the Hall element that is normally caused by device overmolding, temperature dependencies, and thermal stress. The high frequency offset cancellation (chopping) clock allows for a greater sampling rate, which increases the accuracy of the output current signal and results in faster signal processing capability. The A1357 sensor is provided in a lead (Pb) free 3-pin single inline package (KB...