CYStech Electronics Corp.

Spec. No. : C499A4

Issued Date : 2007.09.26

Revised Date :

Page No. : 1/6

CSH277A4

Complementary Output Hall Effect Latched Sink Driver IC

Description

The CSH277A4 is an integrated Hall sensors with output drivers designed for electronic commutation of brushless

DC motor applications. The device includes an on-chip Hall voltage generator for magnetic sensing, a comparator

that amplifies the Hall voltage, and a Schmitt trigger to provide switching hysteresis for noise rejection, and

complementary open collector drivers for sinking large current loads. An internal bandgap regulator is used to

provide temperature compensated supply voltage for internal circuits and allows a wide operating supply range.

If a magnetic flux density larger than threshold BOP, DO is turned on (low) and DOB is turned off (high). The output

state is held until a magnetic flux density reversal falls below Brp causing DO to be turned off and DOB turned on.

CSH277A4 is rated for operation over temperature range from -20℃to 85℃ and voltage range from 3.5V to 20V.

The devices are available in low cost die forms or rugged 4 pin SIP packages.

Features

• On-chip Hall sensor IC with two different sensitivity and hysteresis settings

• Internal bandgap regulator allows temperature compensated operations and a wide operating voltage range

• High output sinking capability up to 400mA for driving large load

• Lower current change rate reduces the peak output voltage during switching

• Build in protection diode for chip reverse power connecting

• Package: SIP-4L

Applications

• Brushless DC motor

• Brushless DC fan

• Revolution counting

• Speed measurement

Functional Block Diagrams

CSH277A4

CYStek Product Specification