MAX1748

The MAX1748 triple-output DC-DC converter in a lowprofile TSSOP package provides the regulated voltages required by active matrix, thin-film transistor (TFT) liquid crystal displays (LCDs). One high-power DC-DC converter and two low-power charge pumps convert the +3.3V to +5V input supply voltage into three independent output voltages.

The primary high-power DC-DC converter generates a boosted output voltage (VMAIN) up to 13V that is regulated within ±1%. The low-power BiCMOS control circuitry and the low on-resistance (0.35Ω) of the integrated power MOSFET allows efficiency up to 93%. The 1MHz current-mode PWM architecture provides fast transient response and allows the use of ultra-small inductors and ceramic capacitors.

The dual charge pumps independently regulate one positive output (VPOS) and one negative output (VNEG). These low-power outputs use external diode and capacitor stages (as many stages as required) to regulate output voltages up to +40V and down to -40V. A proprietary regulation algorithm minimizes output ripple, as well as capacitor sizes for both charge pumps.

The MAX1748 is available in the ultra-thin TSSOP package (1.1mm max height).