ACS709: High Bandwidth, Fast Fault Response Current Sensor IC In Thermally Enhanced - ALLEGRO MICROSYSTEMS - #1

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ACS709 Description The Allegro® ACS709 current sensor IC provides economical and precise means for current sensing applications in industrial, automotive, commercial, and communications systems. The device is offered in a small footprint surface mount package that allows easy implementation in customer applications. The ACS709 consists of a precision linear Hall sensor integrated circuit with a copper conduction path located near the surface of the silicon die. Applied current flows through the copper conduction path, and the analog output voltage from the Hall sensor IC linearly tracks the magnetic field generated by the applied current. The accuracy of the ACS709 is maximized with this patented packaging configuration because the Hall element is situated in extremely close proximity to the current to be measured. High level immunity to current conductor dV/dt and stray electric fields, offered by Allegro proprietary integrated shield technology, guarantees low output ripple and low offset drift in high-side applications. The voltage on the Overcurrent Input (VOC pin) allows customers to define an overcurrent fault threshold for the device. When the current flowing through the copper conduction path (between the IP+ and IP– pins) exceeds this threshold, ACS709-DS, Rev. 1 Features and Benefits Industry-leading noise performance with 120 kHz bandwidth through proprietary amplifier and filter design techniques Integrated shield greatly reduces capacitive coupling from current conductor to die due to high dV/dt, and prevents offset drift in high-side applications Small footprint surface mount QSOP24 package 2100 VRMS isolation voltage between primary current path and sensor IC electronics 1.1 mÙ primary conductor resistance for low power loss User-settable Overcurrent Fault level Overcurrent Fault signal typically responds to an overcurrent condition in < 2 ìs Filter pin capacitor sets analog signal bandwidth ±2% typical output error 3 to 5.5 V, single supply operation Factory trimmed sensitivity, quiescent output voltage, and associated temperature coefficients Chopper stabilization results in extremely stable quiescent output voltage Ratiometric output from supply voltage High Bandwidth, Fast Fault Response Current Sensor IC In Thermally Enhanced Package Continued on the next page… Typical Application RH, RL Sets resistor divider reference for VOC CF Noise and bandwidth limiting filter capacitor COC Fault delay setting capacitor, 22 nF maximum A Use of capacitor required B Use of resistor optional Package: 24 pin QSOP (suffix LF) Approximate Scale 1 2 3 4 5 6 7 8 9 10 11 12 IP+ IP+ IP+ IP+ IP+ IP+ IP– IP– IP– IP– IP– IP– 22 21 20 19 18 17 16 15 NC NC FAULT_EN VOC VCC FAULT VIOUT FILTER VZCR GND NC NC ACS709 COC 0.1 ìF CF 330 kÙ 1 nF VIOUT Fault_EN VCC RH RL IP B A 24 23 14 13