• Product introduction

LTC1625IS

There is no R_SENSE^TMCurrent mode of a synchronous buck switching regulator

description

LTC^®The 1625 is a synchronous step-down switching regulator controller that drives external N-channel power MOSFETs using few external components. MOSFET V_DSInduced current-mode control eliminates the need for a sense resistor and improves efficiency. The frequency of the nominal 150kHz internal oscillator can exceed the frequency of external clock synchronization in the 1.5:1 frequency range. Burst mode^®Low load currents reduce switching losses and low-dropout operation, extending the runtime of battery-powered systems. The forced continuous mode control pin can assist in disabling the regulation of the secondary winding when the main output load is very light when Burst Mode operation is disabled. Foldback current limit and output overvoltage comparator fault protection. The RUN/SS pin is connected to an external capacitor to provide a soft-start function for power sequencing. The wide voltage range allows operation from 3.7V (3.9V for the LTC1625I) to 36V inputs and 1.19V to V outputs.

peculiarity

• Highest efficiency current mode controller
• No sense resistor is required
• Stable high current operation
• Dual N-channel MOSFET synchronous drive
• Wide V_INRange: 3.7V to 36V
• Wide V_OUTRange: 1.19V to V_at
• ± 1% 1.19V reference
• Programmable fixed frequency injection lock
• Out-of-the-box operation: 99% duty cycle with very low dropout pressure
• Force continuous mode control pin
• Optional programmable soft-start
• Pin selectable output voltage
• Foldback current limit
• Output overvoltage protection
• Logic-controlled micropower shutdown_：IQ
• Available in 16-pin narrow SSOP and SO packages