TPS65120, TPS65121, TPS65123, TPS65124
www.ti.com
SLVS531–JUNE 2004
SINGLE-INDUCTOR QUADRUPLE-OUTPUT
TFT LCD POWER SUPPLY
FEATURES
•
Automatic or Programmable Power Se-
quencing
•
Main Output, VMAIN
•
•
•
•
Complete 1 mm Component Profile Solution
2.5 V to 5.5 V Input Voltage Range
Output Short Circuit Protected
16-Pin QFN Package (3 × 3 × 0,9 mm)
– Adjustable Voltage, 3.0 V to 5.6 V/25 mA
– Post-Regulated for Low Ripple (5mVPP
– ±0.8% Typical Accuracy
– Efficiency up to 83%
)
•
•
•
Positive Output, VGH
APPLICATIONS
– Adjustable Voltage up to 20 V/2 mA
– ±3% Typical Accuracy
•
•
•
•
•
•
•
•
Small Form Factor a-Si and LTPS TFT LCD
Cell Phones, Smart Phones
PDAs, Pocket PCs
Portable DVD
Digital-Still Cameras, Camcorders
Handheld Instruments
Negative Output, VGL
– Adjustable Voltage down to -18 V/2 mA
– ± 3% Typical Accuracy
Auxiliary 1.8 V/3.3 V Linear Regulator
Portable GPS
Car Navigation Systems
DESCRIPTION
The TPS6512x DC-DC converter supplies all three voltages required by amorphous-silicon (a-Si) and
low-temperature poly-silicon (LTPS) TFT-LCD displays. The compact layout of the TPS6512x uses a single
inductor to generate independently-regulated positive and negative outputs. A free-running variable peak current
PWM control scheme time-multiplexes the inductor between outputs. This control architecture operates at a
pseudo-fixed-frequency to provide fast response to line and load transients while maintaining a relatively
constant switching frequency and high efficiency over a wide range of input and output voltages. Due to the high
switching frequency capability of the device, inexpensive and ultra-thin 8.2 or 10 µH inductors can be used.
The main output, VMAIN, is post-regulated to provide a low-ripple source drive voltage for the LCD display. The
auxiliary outputs generate a boosted output voltage, VGH, up to 20 V, and a negative output voltage, VGL, down to
-18 V for the LCD gate drive. The device has internal current limiting for high reliability under fault conditions.
Additionally, the device offers a fixed output linear regulator for the LCD logic circuitry.
100
90
TPS65123
D1
80
70
60
VGL
VIN
SWN
VIN
R3
R4
C1
2.2 µ F
down to −18 V/2 mA
2.7 V to 5.5 V
L1
10µH
RUN
EN
C3
100 nF
SWP
FBL
50
40
30
20
10
0
GATE
VGH
VGH
VMAIN
VMAIN
FBM
R5
R6
up to 20 V/2 mA
3.0 V to 5.3 V/25 mA
R1
R2
C2
100 nF
BOOT
C5
FBH
C4
1µ F
220 nF
PGND
AGND
V
IN
− Input Voltage − V
A
A
I
− Load Current − mA
BOOT
Figure 1. Typical Application
Figure 2. Core Converter Efficiency
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright © 2004, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.