6 to 75 V synchronous buck controller

Wide input voltage range synchronous DC-DC step-down controller features extreme voltage conversion ratio over switching frequency range for improved efficiency, thermals, and ripple performance

This feature-rich buck converter includes a Power Good output useful for monitoring and output voltage sequencing for digital ICs during the power-up phase. Embedded protections ensure controlled and safe operation for critical environments in telecom, networking and industrial applications.

Available in a 20-lead QFN mm package with wettable flanks, its embedded gate driver minimizes the number of external components, lowering BOM costs.

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This article describes a synchronous step-down controller application for the telecom sector and can also be used as a guideline for applications in other sectors. The solution is based on our L3751 synchronous buck controller coupled with the ZC1818 shielded power inductor from Coilcraft for a 60 to 12 V conversion with an output current of 10 to 15 A and delivering up to 180W.

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Key features

Wide 6 to 75 V input voltage range
Adjustable output voltage from 0.8 to 60V
100 kHz to 1 MHz switching frequency range
40 nsec minimum on-time for extreme duty ratio
Internal voltage monitoring
Thermal protection
Operating junction temperature range: -40 to 150°C

Application examples

Telecom, networking and industrial applications

Failsafe systems

Unregulated 24V and 48V input voltage bus

Conversion from high voltage battery to 12V and 5V rail

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The 6V to 75V synchronous buck controller : L3751

Looking for a synchronous step-down switching controller with extreme conversion ratios for virtually any application? Start by simulating and analyzing L3751 performance in your industrial bus, telecom & networking, and many other applications.

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L3751: 6 to 75 V input voltage synchronous buck controller