US90A_14 Datasheet, PDF (1/12 Pages) Melexis Microelectronic Systems – 24V Hall IC Fan Driver

US90A / US91A
24V Hall IC Fan Driver
Features and Benefits
 Low cost
 12V/24V fans
 High sensitivity Hall Sensor
 Peak current up to 500mA
Application Examples
 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 packages (all RoHS
Compliant
Ordering Code
Product Code Temperature Code
US90A
E
US90A
E
US91A
E
US90A
E
US90A
E
US91A
E
US91A
E
US90A
E
US91A
E
Package Code
DC
DC
DC
VK
VK
VK
VK
VA
VA
Option Code
AAA-000
AAA-000
AAA-000
AAA-000
AAA-000
AAA-000
AAA-000
AAA-000
AAA-000
Packing Form Code
RE
RX
RX
BU
RX
BU
RX
BU
BU
Legend:
 Package Code:
 Packing Form:
o DC for SOIC150Mil,
o VK for Plastic Single in Line thickness 1.5 - 1.6mm
o VA for Plastic Single in Line thickness 1.1 -1.2mm
o RE for Reel (face up, live bug)
o RX for Reel (face down, dead bug)
 VKAAA000-RX: Trimmed leads: 5.17mm
o BU for Bulk
Ordering example:
US90A-EDC-AAA-000-RE
1 Functional Diagram
2 General Description
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 makes the connectivity with any
external interface such as hardware monitoring or
Super I/O IC easier.
These features are combined with the Melexis patented
no-VDD design to fit the IC in small 4-pin VK and VA
package. The device is also delivered in DC package
for automatic assembly.
3901090263
Rev 008
Page 1 of 12
Data Sheet
Jan/14