TPS65167A

The TPS65167 offers a compact power supply solution to provide all voltages required by a LCD panel for large size monitor and TV panel applications running from a 12-V supply rail.

The device generates all 3 voltage rails for the TFT LCD bias (Vs, VGL and VGH). In addition to that it includes a step-down converter and a LDO controller to provide two logic voltage rails. The device incorporates a high voltage switch that can be controlled by a logic signal from the external timing controller (TCON). This function allows gate voltage shaping for VGH. The device also features a high voltage stress test where the output voltage of VGH is set to typically 30 V and the output voltage of Vs is programmable to any higher voltage. The high voltage stress test is enabled by pulling the HVS pin high. The device consists of a boost converter to provide the source voltage Vs operating at a fixed switching frequency of 750 kHz. A fully integrated positive charge pump, switching automatically between doubler and tripler mode provides an adjustable regulated TFT gate on voltage VGH. A negative charge pump driver provides adjustable regulated output voltages VGL. To minimize external components the charge pumps for VGH and VGL operate at a fixed switching frequency of 1.5 MHz. The device includes safety features like overvoltage protection of the boost converter, short-circuit protection of VGH and VGL as well as thermal shutdown.