A1225

A1225, A1227, and A1229 Hall-Effect Latch for High Temperature Operation FEATURES AND BENEFITS ▪ Symmetrical switchpoints ▪ Superior temperature stability ▪ Operation from unregulated supply ▪ Open-drain 25 mA output ▪ Reverse battery protection ▪ Activate with small, commercially available permanent magnets ▪ Solid-state reliability ▪ Small size ▪ Resistant to physical stress ▪ Enhanced ESD structures result in 8 kV HBM ESD performance without external protection components ▪ Internal protection circuits enable 40 V load dump compliance without external protection components PACKAGES: Not to scale 3-pin SOT23W (suffix LH) 3-pin SIP, matrix HD style (suffix UA) 3-pin SIP, chopper style (suffix UA) DESCRIPTION These Hall-effect latches are extremely temperature-stable and stress resistant sensor ICs especially suited for operation over extended temperature ranges to 150°C. Superior hightemperature performance is made possible through a novel Schmitt trigger circuit that maintains operate and release point symmetry by compensating for temperature changes in the Hall element.Additionally, internal compensation provides magnetic switchpoints that become more sensitive with temperature, hence offsetting the usual degradation of the magnetic field with temperature. The symmetry capability makes these devices ideal for use in pulse-counting applications where duty cycle is an important parameter. The three basic devices (A1225, A1227, and A1229) are identical except for magneti...