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BIPOLAR ANALOG INTEGRATED CIRCUIT

μPC494

SWITCHING REGULATOR CONTROL CIRCUIT

DATA SHEET

Document No. G12649EJ5V0DS00 (5th edition)

Date Published August 2008 NS

Printed in Japan

1988, 2000, 2008

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DESCRIPTION

The

μ PC494 is a PWM type switching regulator control circuit.

Included in this device are a 5 V voltage reference, dual error amplifiers, a variable frequency sawtooth-wave

generating oscillator, a comparator for dead-time control, a flip flop, dual alternating output switches, and a buffer to

output source and sink currents.

Error amplifiers have wide common mode input voltage capability, and circuits for voltage feedback and over current

protection are easy to configure. The

μ PC494 can be applied to all types of switching regulators, including chopper

type regulators.

FEATURES

• 250 mA output buffer to output sink and source currents

• Switchable operation mode between a single-end mode and a push-pull mode

• No double pulsing during transient condition

• Adjustable dead-time (0 to 100%)

• Internal 5 V output voltage reference circuit

• Error amplifiers with phase-compensating function

• Providing master-slave operation (synchronizing multiple ICs)

• With malfunction prevention circuit for low level supply voltage

• Package variations available for different applications

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