L6668 Просмотр технического описания (PDF) - STMicroelectronics

Номер в каталоге

Компоненты Описание

производитель

L6668

SMART PRIMARY CONTROLLER

STMicroelectronics 

L6668

Figure 43 shows a timing diagram where the PFC_STOP function operation is illustrated under different

operating conditions.

Figure 42. How the L6668 can switch off a PFC controller at light load

Vcc

16

L6668

BC557

10 kΩ

14 PFC_STOP

8.2 V

2.2 kΩ

Vcc

PFC

controller

Figure 43. Operation of PFC_STOP function

Vcc

VccON

VccOFF

PFC_STOP

t

COMP

OUT

t

2.2V

2.7V

t

PFC

Gate

Drive

Start-up

Full-load

Light-load

t

Full-load

t

Figure 44. Operation after DIS pin activation: timing diagram

DIS

2.2V

Vcc

VccON

VccON -0.5

VccOFF

Vccrest

OUT

Vin

VHVstart

HV generator is turned on

t

Disable latch is reset here

HV generator is disabled here

t

Input source is removed here

t

t

18/23

Share Link: