US91A, US90A Datasheet - Melexis Microelectronic Systems

US91A - (US90A / US91A) 24V Hall IC Fan Driver

The US90A/91A is a one-chip solution for driving two-coil brushless DC cooling fans. Based on the advanced Melexis CMOS process, the IC contains a Hall-effect sensor, dynamic offset correction and low side output drivers. Frequency Generator or Rotation Detection is available. The open-drain output .

US91A Features

* Low cost High sensitivity Hall Sensor Locked rotor protection and auto-restart Power-efficient CMOS and power MOSFETs Built-in output protection clamping diode Integrated tachometer (US90A) or alarm (US91A) signal output 2-coil fan driver with FG/RD output in 4-pin VK / VA and 8-pin narrow SOIC pack

US90A_MelexisMicroelectronicSystems.pdf