The main output, VO1, is a 1.6-MHz, fixed-frequency PWM boost converter providing the source drive voltage for the LCD display. The device is available in two versions with different internal switch current limits to allow the use of a smaller external inductor when lower output power is required. The TPS65100/01 has a typical switch current limit of 2.3 A, and the TPS65105 has a typical switch current limit of 1.37 A. A fully integrated adjustable charge pump doubler/tripler provides the positive LCD gate drive voltage. An externally adjustable negative charge pump provides the negative gate drive voltage. Due to the high 1.6-MHz switching frequency of the charge pumps, inexpensive and small 220-nF capacitors can be used. The TPS6510x series has an integrated VCOM buffer to power the LCD backplane. For LCD panels powered by 5 V only, the TPS6510x series has a linear regulator controller using an external transistor to provide a regulated 3.3-V output for the digital circuits. For maximum safety, the TPS65100/05 goes into shutdown as soon as one of the outputs is out of regulation. The device can be enabled again by toggling the input or the enable (EN) pin to GND. The TPS65101 does not enter shutdown when one of the outputs is below its power good threshold.