MC34262

Preliminary

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

2 of 6

www.unisonic.com.tw

QW-R114-006 .a

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MARKING

DIP-8

SOP-8

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PIN CONFIGURATION

FB

COMP

MULT

CS

GD

GND

ZCD

1

2

3

4

8

7

6

5

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PIN DESCRIPTION

PIN NO.

PIN NAME

DESCRIPTION

1

FB

Iverting input of the error amplifier. The information on the out voltage of the

boost converter is fed into the pin through a resistor divider.

2

COMP

Out of the error amplifier. This pin is connected to ground via a compensation

capacitor to achieve stability of the voltage control loop.

3

MULT

Input to the multiplier. This pin is connected to the line voltage after the birdge

rectified diodes via a resistor divider to provide sinusoidal reference voltage to the

current loop.

4

CS

Input to the CS comparator. The MOSFET current is sensed by a resistor, the

resulting voltage is applied to this pin and compared with an internal

sinusoidal-shaped reference generated by the multiplier to determine the

MOSFET's turn off.

5

ZCD

Zero Current Detector input. This pin is connected to the auxiliary winding via a

resistor to sense the inductor current zero crossing point by monitoring the

auxiliary winding voltage falls blow 1.4V. When activated, a new switching cycle

starts.

6

GND

Ground pin.

7

GD

Gate driver out. The totem pole output stage is able to driver power MOSFET,

The high-level voltage of the pin is clamped at about 16V.

8

VCC

Supply voltage of driver and control circuits.