LT3513 Datasheet, PDF (1/20 Pages) Linear Technology – 2MHz High Current 5-Output Regulator for TFT-LCD Panels

LT3513
2MHz High Current
5-Output Regulator
for TFT-LCD Panels
FEATURES
n _{4.5V to 30V Input Voltage Range}
n _{Four Integrated Switches: 2.2A Buck, 1.5A Boost,}
0.25A Boost, 0.25A Inverter (Guaranteed Minimum
Current Limit)
n _{External NPN LDO Driver}
n _{Fixed Frequency, Low Noise Outputs}
n _{Inductor Current Sense for Buck}
n _{Soft-Start for All Outputs}
n _{Externally Programmable VON Delay}
n _{Three Integrated Schottky Diodes}
n _{PGOOD Pin for AVDD Output Disconnect}
n _PanelProtect^TM _{Circuitry Disables VON Upon Fault}
n _{Thermally Enhanced 38-Lead 5mm × 7mm QFN}
Package
APPLICATIONS
n _{Automotive TFT-LCD Displays}
n _{Large TFT-LCD Desktop Monitors}
n _{Flat Panel Televisions}
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
regulator provides a low voltage output, V_LOGIC, with up
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:
AV_DD, V_ON and V_OFF required by the LCD panel. A high-side
PNP provides delayed turn-on of the V_ON signal and can
handle up to 30mA. Protection circuitry ensures that V_ON
is disabled if any of the four outputs are more than 10%
below the programmed voltage.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
PanelProtect is a trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
V_IN
8V TO 16V
V_OFF
–10V
20mA
2.2μF
0.47μF
10μH
69.8k
10k
V_LOGIC
5V
0.5A
30.1k
22μF
10k
V_LDO
3.3V
0.5A
10μF
42.2k
10k
10μF 178k
V_LOGIC
5V
10μH
53.6k 100k
60.4k
UVLO LDOPWR V_IN
SW4
D4
NFB4
4.7μH
0.22μF
BIAS
BOOST
SW1
SENSE⁺
SENSE^–
FB1
LT3513
BD
FB5
V_C1 V_C2 GND
SW2
FB2
PGOOD
RUN-SS1
RUN-SS2
RUN-SS3/4
C_T
V_{ON_CLK}
V_ON
V_ONSINK
E3
SW3
FB3
V_C3 V_C4
10k
10μF
47nF
V_{ON_CLK}
232k
15nF
6.8μH
165k
V_LOGIC
5V
10k
7.5k
4.7k
30k
13k
2.7nF
4.7nF 1.5nF
2.2nF
AV_DD
8V
80mA
15nF
15nF
RUN/SS 2V/DIV
V_LOGIC 5V/DIV
AV_DD 10V/DIV
V_OFF 10V/DIV
2.2μF
V_ON
22V
20mA
V_E3 20V/DIV
0.47μF
V_ON 20V/DIV
I_IN(AVG) 1A/DIV
Start-Up Waveforms
5ms/DIV
3513 TA01b
3513fa
1