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FEATURES
· Main Output, VMAIN
– 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
– Adjustable Voltage up to 20 V/2 mA
– ±3% Typical Accuracy
· Negative Output, VGL
– Adjustable Voltage down to -18 V/2 mA
– ±3% Typical Accuracy
· Auxiliary 1.8 V/3.3 V Linear Regulator
· Automatic or Programmable Power
Sequencing
· 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, 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.
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