SHINDENGEN

ELECTRIC MFG.CO.,LTD

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2.6

Phase compensation

Master

The PFC converter must be adjusted so that it does not respond to commercial AC input frequencies.

Capacitors (C113 and C114) and a resistor (R117) are connected between the COMP pin and

GND pin of the master IC to correct the phase of the amplifier and reduce the feedback loop gain

at commercial AC input frequencies. Fig. 13 shows an example circuit. We recommend a C114 of

about 2.2 uF, C113 of 0.22 uF, and R117 of 1 kΩ. See Section 4.6 for information on adjusting

the COMP pin.

Fig. 13 COMP pin connection example

2.7

Gate driver

Master

Slave

The signal output from the OUT pin determines the turn-on and turn-off timings for each switch.

The OUT pin receives a supply from the power supply voltage VCC. The gate driver capacity is

0.5 A (Source) and 1.2 A (Sink).

Fig. 14 shows examples of commonly used driver circuits.

When a discharging diode (D112) is used as shown in Examples A and B, use a small-capacity

Schottky diode or other such diode. Do not use a snappy (hard) recovery diode. We recommend

D1NS4 (axial) or M1FM3 (surface mounting).

If the Qg of MOSFET (Q111) is large and when full discharge is not possible, add a PNP transistor

(Q112) on the discharge side as shown in the example C), Fig. 14.

Fig. 14 Gate driver circuit