Two Complete PWM Control Circuits
Outputs Drive MOSFETs Directly
Oscillator Frequency . . . 50 kHz to 2 MHz
3.6-V to 20-V Supply-Voltage Range
Low Supply Current . . . 3.5 mA Typ
Adjustable Dead-Time Control, 0% to 100%
1.26-V Reference

description
The TL1454A is a dual-channel pulse-width-modulation
(PWM) control circuit, primarily intended
for low-power, dc/dc converters. Applications
include LCD displays, backlight inverters, notebook
computers, and other products requiring
small, high-frequency, dc/dc converters.
Each PWM channel has its own error amplifier, PWM comparator, dead-time control comparator, and MOSFET
driver. The voltage reference, oscillator, undervoltage lockout, and short-circuit protection are common to both
channels.
Channel 1 is configured to drive n-channel MOSFETs in step-up or flyback converters, and channel 2 is
configured to drive p-channel MOSFETs in step-down or inverting converters. The operating frequency is set
with an external resistor and an external capacitor, and dead time is continuously adjustable from 0 to 100%
duty cycle with a resistive divider network. Soft start can be implemented by adding a capacitor to the dead-time
control (DTC) network. The error-amplifier common-mode input range includes ground, which allows the
TL1454A to be used in ground-sensing battery chargers as well as voltage converters.