TWO PHASE HALL EFFECT LATCH WITH FG OUTPUT

AH211

1

Feb. 2010 Rev. 1. 7

BCD Semiconductor Manufacturing Limited

Data Sheet

General Description

The AH211 is an integrated Hall sensor with output

driver and frequency generator designed for electronic

commutation of brush-less DC motor applications. The

device includes an on-chip Hall sensor for magnetic

sensing, an amplifier that amplifies the Hall voltage, a

Schmitt trigger to provide switching hysteresis for

noise rejection, a temperature compensation circuit to

compensate the temperature drift of Hall sensitivity,

two complementary open-collector drivers for sinking

large load current. It also includes an internal band-gap

regulator which is used to provide bias voltage for

internal circuits.

Place the device in a variable magnetic field, while the

magnetic flux density is larger than threshold BOP, DO

will be turned on (low) and DOB (and FG) will be

turned off (high). This output state is held till the mag-

netic flux density reversal falls below BRP causing DO

to be turned off (high) and DOB (and FG) turned on

(low).

AH211 is available in TO-94 (SIP-4L) package.

Features

·

On-Chip Hall Sensor

·

3.5V to 16V Supply Voltage

·

400mA (avg) Output Sink Current

·

·

Built-in FG Output

·

Low Profile TO-94 (SIP-4L) Package

·

ESD Rating: 600V (Machine Model)

Applications

·

Dual-Coil Brushless DC Motor

·

Dual-Coil Brushless DC Fan

·

Revolution Counting

·

Speed Measurement

Figure 1. Package Type of AH211

TO-94