AH5798

SINGLE PHASE HALL EFFECT LATCH SMART

FAN MOTOR CONTROLLER

AH5798 Rev. 1

3 of 9

OCTOBER 2009

www.diodes.com

Frequency

Generator

Lock

Detector

Soft Switching

Control

Hall

Sensor

AMP

Vdd

FG

O1

O2

Power

Vss

Logic

Block

Full Bridge

Driver

Operating

FG

O1

O2

Ton

Toff

“Re-start spinning”

motor locked cleared

motor locked detected

Mechanical lock

Magentic

S

N

Normal spinning

Notes:

4. In “Normal spinning, the FG shall change its state at each rising edge of O1.

5. When magnetic is locked as “S” pole, then O2 is kept on “L”, O1 is a clock with Ton/Toff ratio. When magnetic is locked at “N” pole, then O1 is

kept on “L”, O2 is a clock with Ton/Toff ratio.

6. When “Re-start spinning” occurs, the motor shall ramp up to the “Normal Spinning” speed from zero. It depends on the motor characteristics.

Block Diagram