點晶科技股份有限公司

SILICON TOUCH TECHNOLOGY INC.

ST1111N

SP-ST1111N-A.004(2007-07-12)

Version

：

A.004

Page

：1

ST1111N

Single Coil Brushless DC Motor Drivers

( 1.5 to 7.5 Volts )

General Specifications

The device is designed specifically for electronic commutation of single coil DC

motor applications.

They are intended to be used as an interface between

HALL effect latch and a single coil load.

Each device includes a power reverse

protected diode, a fan tachometer for dividing the frequency of tachometer pulses

from the driver with 2, a lock detection circuit to shut down the drivers for

overheat prevention, and complementary bi-directional drivers for driving and

sinking large load on a single silicon chip.

Though the DC brushless motor

driver can be started as low voltage as 1.5 Volt to 2 Volt and the device permits

operation with supply voltage of 1.5 to 7.5 Volts, the design, specifications and

performance have been optimized for 3V and 5V brushless DC motor

applications.

The output driver node O1/O2 will be “turned to sink/drive” for V(HIN) = logic

low.

Similarly, the output O1/O2 will be “turned to drive/sink” for V(HIN) =

logic high .

If the motor rotation is stalled by external force or obstacles, overdrive current

( or lock current ) may incur coil overheat/burning.

To prevent coil

overheat/burning, these devices incorporate lock detection circuit to shut down

the drivers.

After the motor locking is released, the drivers can be powered up

using an automatic self-restart circuit.

The drivers are shut down roughly 1 to 3

seconds after the motor is locked. After the drivers are shut down, the automatic

self-restart circuit will try to power up the drivers every 1 to 3 seconds