TPS65120 Datasheet, PDF (1/23 Pages) Texas Instruments – SINGLE-INDUCTOR QUADRUPLE-OUTPUT TFT LCD POWER SUPPLY

www.ti.com
TPS65120, TPS65121, TPS65123, TPS65124
SLVS531 – JUNE 2004
SINGLE-INDUCTOR QUADRUPLE-OUTPUT
TFT LCD POWER SUPPLY
FEATURES
• Main Output, V_MAIN
– Adjustable Voltage, 3.0 V to 5.6 V/25 mA
– Post-Regulated for Low Ripple (5mV_PP)
– ±0.8% Typical Accuracy
– Efficiency up to 83%
• Positive Output, V_GH
– Adjustable Voltage up to 20 V/2 mA
– ±3% Typical Accuracy
• Negative Output, V_GL
– Adjustable Voltage down to -18 V/2 mA
– ± 3% Typical Accuracy
• Auxiliary 1.8 V/3.3 V Linear Regulator
• Automatic or Programmable Power Se-
quencing
• 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)
APPLICATIONS
• Small Form Factor a-Si and LTPS TFT LCD
• Cell Phones, Smart Phones
• PDAs, Pocket PCs
• Portable DVD
• Digital-Still Cameras, Camcorders
• Handheld Instruments
• 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, V_MAIN, is post-regulated to provide a low-ripple source drive voltage for the LCD display. The
auxiliary outputs generate a boosted output voltage, V_GH, up to 20 V, and a negative output voltage, V_GL, 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.
V_IN
C1
2.7 V to 5.5 V _{2.2 µ F}
V_GH
up to 20 V/2 mA
C2
100 nF
TPS65123
VIN
SWN
RUN
EN
GATE
VGH
R1
FBH
R2
SWP
FBL
VMAIN
FBM
BOOT
D1
R3
L1
10 µH
R4
R5
C4 R6
1µ F
V_GL
down to −18 V/2 mA
C3
100 nF
V_MAIN
3.0 V to 5.3 V/25 mA
C5
220 nF
AGND
A
PGND
A
Figure 1. Typical Application
100
90
80
70
60
50
40
30
20
10
0
V_IN − Input Voltage − V
I_BOOT − Load Current − mA
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.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2004, Texas Instruments Incorporated