LT3742 Datasheet | Linear Technology

Features n Wide Input Voltage Range: 4V to 30V n Wide Output Voltage Range: 0.8V to VIN n Low Shutdown IQ: 20µA n Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise n 0.8V ±1.5% Voltage Reference n 500k Hz Current Mode Fixed Frequency Operation n Internal Boost Converter Provides Bias Rail for N-channel MOSFET Gate Drive n Power Good Voltage Monitor for Each Output n Programmable Soft-Start n 24-Lead 4mm × 4mm × 0.75mm Package Applications n Satellite and Cable TV Set-Top Boxes n Distributed Power Regulation n Automotive Systems n Super Capacitor Charger LT3742 Dual, 2-Phase Step-Down Switching Controller Description The LT®3742 is a dual step-down DC/DC switching regulator controller that drives high side N-channel power MOSFETs. A 500k Hz fixed frequency current mode architecture provides fast transient response with simple loop pensation ponents and cycle-by-cycle current limiting. The output stages of the two controllers operate 180° out of phase to reduce the input ripple current, minimizing the noise induced on the input supply, and allowing less input capacitance. An internal boost regulator generates a bias rail of VIN + 7V to provide gate drive for the N-channel MOSFETs allowing low dropout and 100% duty cycle operation. The LT3742 can be used for applications where both controllers need to operate independently, or where both controllers are used to provide a single higher current output. The device is available in a thermally enhanced 4mm × 4mm QFN package. L, LT, LTC, LTM, Linear Technology, the Linear logo, Poly Phase and Burst Mode are registered trademarks and No RSENSE is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application 8V and 5V Dual Step-Down Converter VIN VOUT1 8V 4A 47µF RUN1 10µH 4.7µF 14V 45.3k VIN 1µF UVLO SWB BIAS 20.0k 10µF 0.010Ω 6.5µH 1.8k 200Ω G1 G2 SSSEWENN1SSEE11+-...