器件名称:
TL1454ACN
功能描述:
DUAL-CHANNEL PULSE-WIDTH-MODULATION (PWM) CONTROL CIRCUIT
文件大小:
409.96KB 共27页
简 介:
TL1454A, TL1454AY DUAL-CHANNEL PULSE-WIDTH-MODULATION (PWM) CONTROL CIRCUIT SLVS423 A– MAY 2002 – REVISED SEPTEMBER 2002 D D D D D D D 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 D, N OR PW PACKAGE (TOP VIEW) 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. CT RT DTC1 IN1 + IN1 – COMP1 GND OUT1 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 REF SCP DTC2 IN2 + IN2 – COMP2 VCC OUT2 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 e……
