Description
A4945 and A4949 Three Phase Sensorless Sinusoidal Fan Driver .
The A4945 and A4949 three phase motor drivers incorporate sinusoidal drive to minimize audible noise and vibration for medium power fans.
Features
* 180° sinusoidal drive for low audible noise
* High efficiency control algorithm
* Sensorless operation
* Analog Speed input (A4945)
* PWM Speed input (A4949)
* Wide supply voltage range
* FG speed output
* Lock detection
* Ove
Applications
* Both packages are lead (Pb) free with 100% matte-tin leadframe plating. 8-pin SOICN
8-pin SOICN
with exposed thermal pad
(L package)
(LJ package)
Not to scale
Functional Block Diagram
VBB
50 kΩ
Speed Demand Input
PWM 100 kΩ
Duty Cycle FG
A4949 device shown
TSD
IDC Protection
VREG
VR