Pin connection

L6564

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Doc ID 16202 Rev 1

6PFC_OK

PFC pre-regulator output voltage monitoring/disable function. This pin senses the output

voltage of the PFC pre-regulator through a resistor divider and is used for protection purposes.

If the voltage on the pin exceeds 2.5V the IC stops switching and restarts as the voltage on the

pin falls below 2.4V. However, if the voltage of the INV pin falls 40 mV below that of the pin

PFC_OK, a feedback failure is assumed. In this case the device is latched off. Normal operation

can be resumed only by cycling Vcc. bringing its value lower than 6V before to move up to Turn-

on threshold.

If the voltage on this pin is brought below 0.23V the IC is shut down. To restart the IC the

voltage on the pin must go above 0.27V. This can be used as a remote on/off control input.

7ZCD

Boost inductor’s demagnetization sensing input for transition-mode operation. A negative-going

edge triggers MOSFET’s turn-on.

8

GND

Ground. Current return for both the signal part of the IC and the gate driver.

9GD

Gate driver output. The totem pole output stage is able to drive power MOSFET’s and IGBT’s

with a peak current of 600 mA source and 800 mA sink. The high-level voltage of this pin is

clamped at about 12V to avoid excessive gate voltages.

10

Vcc

Supply Voltage of both the signal part of the IC and the gate driver. Sometimes a small bypass

capacitor (0.1 µF typ.) to GND might be useful to get a clean bias voltage for the signal part of

the IC.

Table 3.

Pin description (continued)

n°

Name

Function