LT3513
2MHz High Current
5-Output Regulator
for TFT-LCD Panels
FEATURES
DESCRIPTION
The LT®3513 5-output adjustable switching regulator
provides power for large TFT-LCD panels. The 38-pin
5mm × 7mm QFN device can generate a 3.3V or 5V logic
supply along with the triple output supply required for the
TFT-LCD panel. A lower voltage secondary logic supply
may also be generated with the addition of an external
NPN driven by the internal linear regulator. A step-down
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4.5V to 30V Input Voltage Range
Four Integrated Switches: 2.2A Buck, 1.5A Boost,
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0.25A Boost, 0.25A Inverter (Guaranteed Minimum
Current Limit)
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External NPN LDO Driver
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Fixed Frequency, Low Noise Outputs
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Inductor Current Sense for Buck
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Soft-Start for All Outputs
regulator provides a low voltage output, V
, with up
LOGIC
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Externally Programmable V Delay
to 1.2A of current while capable of operating from a wide
input range of 4.5V to 30V. A high power step-up con-
verter, a lower power step-up converter and an inverting
converter provide the three independent output voltages:
ON
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Three Integrated Schottky Diodes
PGOOD Pin for AV Output Disconnect
DD
PanelProtectTM Circuitry Disables V Upon Fault
ON
Thermally Enhanced 38-Lead 5mm × 7mm QFN
Package
AV , V andV requiredbytheLCDpanel. Ahigh-side
DD ON OFF
PNP provides delayed turn-on of the V signal and can
ON
handle up to 30mA. Protection circuitry ensures that V
ON
is disabled if any of the four outputs are more than 10%
APPLICATIONS
below the programmed voltage.
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Automotive TFT-LCD Displays
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
PanelProtect is a trademark of Linear Technology Corporation.
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Large TFT-LCD Desktop Monitors
All other trademarks are the property of their respective owners.
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Flat Panel Televisions
TYPICAL APPLICATION
10μH
V
V
IN
LOGIC
5V
8V TO 16V
10μF
178k
53.6k
10k
100k
10μF
0.47μF
V
OFF
–10V
60.4k
20mA
UVLO LDOPWR
SW4
V
SW2
FB2
IN
AV
DD
2.2μF
10μH
8V
Start-Up Waveforms
80mA
69.8k
10k
D4
PGOOD
NFB4
BIAS
RUN-SS1
RUN-SS2
RUN/SS 2V/DIV
BOOST
RUN-SS3/4
V
5V/DIV
LOGIC
AV 10V/DIV
0.22μF
4.7μH
C
T
DD
OFF
V
47nF
15nF
15nF
15nF
SW1
LOGIC
5V
0.5A
V
10V/DIV
LT3513
+
SENSE
SENSE
FB1
–
30.1k
V
V
ON_CLK
ON_CLK
V
ON
V
ON
22V
22μF
10k
232k
20mA
V
ONSINK
E3
V
20V/DIV
E3
V
20V/DIV
1A/DIV
ON
6.8μH
165k
10k
V
I
LOGIC
IN(AVG)
BD
FB5
SW3
FB3
5V
V
3.3V
0.5A
LDO
0.47μF
3513 TA01b
5ms/DIV
V
V
GND
V
V
C4
C1
C2
C3
42.2k
10k
2.2μF
10μF
7.5k
2.7nF
4.7k
30k
13k
2.2nF
4.7nF 1.5nF
3513fa
1