FAN7319 Datasheet, PDF (4/23 Pages) Fairchild Semiconductor – LCD Backlight Inverter Drive IC

Pin Definitions
Pin #
1
2
Name
VOLP
REF
3
BDIM
4
ADIM
5
CMP
6
TIMER
7
RT
8
RT1
9
SENSE
10
GND
11
OUTD
12
OUTC
13
OUTB
14
OUTA
15
VIN
16
OLR
17
OLP
18
MODE
19
OVPR
20
ENA
Description
This pin is for reference voltage of open-lamp protection level in striking mode.
This pin is 5V reference output.
This pin is the input for burst dimming. Input type is PWM pulse signal, not DC voltage.
Dimming polarity is positive.
This pin is for positive analog dimming.
Error amplifier output. Typically, a compensation capacitor is connected to this pin from the
ground.
This pin is for protection delay setting. Typically, a capacitor is connected to this pin from
ground. OVP/OLP/High_CMP/SLP protection time is set by this capacitor value.
This pin is for programming the normal switching frequency. Typically, a resistor is
connected to this pin from ground.
This pin is for programming the striking switching frequency. In striking mode, this pin is
connected to ground. Typically, a resistor is connected to this pin from the RT pin.
This pin is for sensing Zero Voltage Switching (ZVS) timing. If voltage cross 0V, CT voltage
is reset; and operating frequency is changed by ZVS timing. If this pin is not used, it must be
connected to REF.
This pin is the ground.
This pin is lower NMOS gate-drive output 2. (Push-Pull : Disabled)
This pin is upper NMOS gate-drive output 2. (Push-Pull : Disabled)
This pin is lower NMOS gate-drive output 1. (Push-Pull : NMOS gate-drive output 2)
This pin is upper NMOS gate-drive output 1. (Push-Pull : NMOS gate-drive output 1)
This pin is the supply voltage of the IC.
This pin is for open-lamp regulation. It is connected to the full-wave rectifier internally. If two
feedbacks are available, sum of feedback is inputted to this pin. When OLR input is between
2V and 3V, the error amplifier output current is limited to 3µA. When OLR input reaches 3V,
the error amplifier output current is 0A and its output voltage maintains constant. OLR input
is inputted to the negative of another error amplifier for feedback control of lamp voltage.
When OLR input is more than 3.3V, another error amplifier for OLR is operating and lamp
voltage is regulated.
This pin is for open-lamp protection and feedback control of lamp currents. It is connected to
the full-wave rectifier internally. If two feedbacks are available, sum of rectified feedback is
inputted to this pin. In striking mode, if OLP input is less than 1V; or in normal mode, if OLP
input is less than 0.5V; the IC shuts down to protect the system in open-lamp condition.
Shutdown time is programmed by the capacitor value connected to the TIMER pin. OLP
input is inputted to the negative of the error amplifier for feedback control of lamp current.
This pin is for topology selection. If this pin is connected to REF, it is push-pull topology;
OUTC & OUTD is disabled. If this pin is connected to GND, it is full-bridge topology.
This pin is for reference voltage of Over-Voltage Protection (OVP).
This pin is for turning on/off the IC. If enable voltage is lower than 2.1V, DCR mode is
disabled. If enable voltage is higher than 2.5V, DCR mode is activated and OLP is disabled.
© 2010 Fairchild Semiconductor Corporation
FAN7319 • 1.0.1
4
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