FAN7319 Просмотр технического описания (PDF) - Fairchild Semiconductor

Номер в каталоге

Компоненты Описание

Список матч

FAN7319

LCD Backlight Inverter Drive IC

Fairchild Semiconductor 

Short-Lamp Protection

If

the

minimum

of

the

rectified

OLR

voltages

(

V min

OLR

)

is

less than 0.5V in normal mode, the IC is shut down after

a delay of 20ms, as shown in Figure 44. In DCR mode

(VENA>2.5V),

if

V min

OLR

is

less

than

0.5V

in

normal

mode;

the IC operates normally without shutdown, as shown in

Figure 45. This protection is disabled in striking mode to

ignite lamps reliably.

CMP-High Protection

If CMP is 2.5V in normal mode, OLP peak voltage is

higher than ADIM voltage and CMP voltage is holding at

2.5V. If CMP is 2.5V in normal mode, OLP peak voltage

is lower than ADIM voltage and CMP is charged by 1µA

current source. If CMP is higher than 3V, the IC is shut

down after a delay of 500ms, as shown in Figure 46. This

protection is disabled in striking mode to ignite lamps

reliably. To remove CMP-HIGH protection, connect a

1MΩ resistor to CMP capacitor in parallel. Unless 1µA

sourcing current flows into the resistor, CMP voltage

cannot be charged.

Figure 44. Short-Lamp Protection in Normal Mode

Figure 46. CMP-High Protection in Normal Mode

Thermal Shutdown

The IC provides a function to detect abnormal over-

temperature. If the IC temperature exceeds

approximately 150°C, the thermal shutdown triggers.

Figure 45. Short-Lamp Protection in DCR Mode

© 2010 Fairchild Semiconductor Corporation

FAN7319 • 1.0.1

18

www.fairchildsemi.com

Share Link: