A1225, A1227, and A1229 Hall Effect Latch for High Temperature Operation Features and Benefits Description Symmetrical switchpoints These Hall-effect latches are extremely temperature-stable Superior temperature stability and stress resistant sensor ICs especially suited for operation Operation from unregulated supply over extended temperature ranges to 150C. Superior high- Open-drain 25 mA output temperature performance is made possible through a novel Reverse Battery protection Schmitt trigger circuit that maintains operate and release Activate with small, commercially available point symmetry by compensating for temperature changes permanent magnets in the Hall element. Additionally, internal compensation Solid-state reliability provides magnetic switchpoints that become more sensitive Small size with temperature, hence offsetting the usual degradation of Resistant to physical stress the magnetic field with temperature. The symmetry capability Enhanced ESD structures result in 8 kV HBM ESD makes these devices ideal for use in pulse-counting applications performance without external protection components where duty cycle is an important parameter. The three basic Internal protection circuits enable 40 V load dump devices (A1225, A1227, and A1229) are identical except for compliance without external protection components magnetic switchpoints. Each device includes on a single silicon chip a voltage regulator, Packages: Hall-voltage generator, temperature compensation circuit, signal amplifier, Schmitt trigger, and a buffered open-drain 3-pin SIP output to sink up to 25 mA. The on-board regulator permits (suffix UA) operation with supply voltages of 3.8 to 24 V. The first character of the part number suffix determines the device operating temperature range. Suffix L is for 40C to 150C. Two package styles provide a magnetically optimized package for most applications. Suffix LT is a miniature SOT89/ TO-243AA transistor package for surface-mount applications, 3-pin SOT89 suffix UA is a three-lead ultra-mini-SIP. Both packages are lead (suffix LT) (Pb) free with 100% matte tin leadframe plating. Not to scale Functional Block Diagram Regulator VCC To All Subcircuits Clock / Logic VOUT AMP Anti-aliasing Tuned Filter LP-Filter GND A1225-DS, Rev. 1 Hall Chopping LogicA1225, A1227 Hall Effect Latch for High Temperature Operation and A1229 Selection Guide Ambient B (min) B (max) RP OP * Part Number Packing Package Temperature, T (G) (G) A A1225LLTTR-T 7-in. reel, 1000 pieces/reel 3-pin SOT89 surface mount 40C to 150C 300 300 A1225LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1227LLTTR-T 7-in. reel, 1000 pieces/reel 3-pin SOT89 surface mount 40C to 150C 175 175 A1227LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole A1229LLTTR-T 7-in. reel, 1000 pieces/reel 3-pin SOT89 surface mount 40C to 150C 200 200 A1229LUA-T Bulk, 500 pieces/bag 3-pin SIP through hole *Contact Allegro for additional packaging options. Absolute Maximum Ratings Characteristic Symbol Notes Rating Unit Forward Supply Voltage V 30 V CC Reverse Supply Voltage V 30 V RCC Output Off Voltage V 30 V OUT Reverse Output Voltage V 0.5 V ROUT Continuous Output Current I 25 mA OUT(SINK) Operating Ambient Temperature T Range L 40 to 150 C A Maximum Junction Temperature T (max) 165 C J Storage Temperature T 65 to 170 C stg Pin-out Diagrams Terminal List Table Package LT Package UA Number Name Function 1 VCC Input power supply 2 GND Ground 3 VOUT Output signal 2 3 1 1 23 Allegro MicroSystems, Inc. 2 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000 www.allegromicro.com