A1128 Highly Programmable Hall-Effect Switch FEATURES AND BENEFITS DESCRIPTION Chopper stabilization for stable switchpoints throughout The A1128 is a field-programmable, unipolar Hall-effect switch operating temperature range designed for use in high-temperature applications. This device Externally programmable: uses a chopper-stabilization technique to eliminate offset Operate point (through the VCC pin) inherent in single-element devices. Output polarity The devices are externally programmable. A wide range of Output fall time for reduced EMI in programmability is available on the magnetic operate point, automotive applications B , while the hysteresis remains fixed. This advanced OP On-board voltage regulator for 3 to 24 V operation feature allows optimization of the sensor IC switchpoint and On-chip protection against: can drastically reduce the effects of mechanical placement Supply transients tolerances found in end-use production environments. Output short-circuits Reverse battery condition A proprietary dynamic offset cancellation technique, with an internal high-frequency clock, reduces the residual offset voltage, which is normally caused by device overmolding, temperature dependencies, and thermal stress. Having the Hall PACKAGES: element and amplifier in a single chip minimizes many problems normally associated with low-level analog signals. LAST-TIME BUY Two package styles provide a magnetically optimized package for most applications. Type LT is a miniature SOT89/TO-243AA surface mount package that is thermally enhanced with an 3-pin SIP 3-pin SOT89 (suffix UA, (suffix LT) exposed ground tab, and type UA is a three-lead ultramini SIP TS leadform) for through-hole mounting. The packages are lead (Pb) free, with 100% matte-tin-plated leadframes. Not to scale 3-pin SIP (suffix UA) Functional Block Diagram V+ Regulator To All Subcircuits VCC Trim Control TC Trim Switchpoint VOUT C BYPASS Amp Signal Recovery Output Fall Time Program Control Output Polarity GND A1128-DS, Rev. 4 December 7, 2018 MCO-0000498 Dynamic Offset CancellationA1128 Highly Programmable Hall-Effect Switch SELECTION GUIDE 1 Part Number Packing Package 2 A1128LLTTR-T 7-in. reel, 1000 pieces/reel 3-pin SOT89/TO-243 surface mount A1128LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1128LUATS-T 13-in. reel, 4000 pieces/reel 3-pin SIP, TS leadform, surface mount 1 Contact Allegro for additional packaging options. 2 Last-Time Buy: This package variant has reached the end of its life cycle and will no longer be offered by Allegro. This product is considered obsolete and customer notification has been provided. All orders are accepted as final builds. Date of status change: September 3, 2018. Recommended replacement: A1128LUATS-T. ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Notes Rating Unit Forward Supply Voltage V 28 V CC Reverse Supply Voltage V 18 V RCC Forward Output Voltage V 26.5 V OUT Reverse Output Voltage V 0.7 V ROUT Output Sink Current I VCC to VOUT 20 mA OUT(SINK) Operating Ambient Temperature T L temperature range 40 to 150 C A Maximum Junction Temperature T (max) 165 C J Storage Temperature T 65 to 170 C stg Pinout Diagrams Terminal List Table Number Name Function 1 VCC Input power supply 2 GND Ground 3 VOUT Output signal 1 2 3 1 2 3 LT Package UA Package 2 Allegro MicroSystems, LLC 955 Perimeter Road Manchester, NH 03103-3353 U.S.A. www.allegromicro.com VCC GND VOUT VCC GND VOUT