Description

The 6 V to 75 V wide input voltage range L3751 synchronous buck controller features

extreme voltage conversion ratio over switching frequency range (100 kHz - 1 MHz)

thanks to 40 nsec minimum conduction time.

The diode emulation (DEM) implements pulse skipping mode that maximizes the

efficiency at light-load giving controlled output voltage ripple. The forced PWM

(FPWM) over the load range makes the switching frequency constant and minimizes

the output voltage ripple.

The Power Good open collector output validates the regulated output voltage for

monitoring and it is useful to implement output voltage sequencing for digital ICs

during the power-up phase.

An embedded gate driver minimizes the number of external components and it is

designed for standard VTH MOSFET.

Embedded protections–output overcurrent, input voltage UVLO, internal voltage

monitoring, thermal shutdown - feature controlled and safe operation for critical

environments in telecom, networking and industrial applications.

The device is available in a QFN 20 leads 3.5 x 4.5 mm package with wettable flanks.

Features

• Wide 6 V to 75 V input voltage range

• Adjustable output voltage from 0.8 V to 60 V

• 100 kHz - 1 MHz switching frequency range

• 40 nsec minimum on-time for extreme duty ratio

• Low dropout operation during line transient

• Adjustable soft-start or input voltage tracking

• Pulse skipping or forced PWM operation at light load

• Synchronization

• Adjustable precision enable

• Power Good open collector output validates VOUT

• 7.5 V gate drivers for standard VTH MOSFETs

• Constant current protection with hiccup mode

• Precision or lossless programmable current sensing

• Improved line transient response

• Input voltage undervoltage lockout

• Internal voltage monitoring

• Thermal protection

• Operating junction temperature range: -40 °C to 150 °C

Applications

• Telecom, networking and industrial applications

• Failsafe systems

• Unregulated 24 V and 48 V input voltage bus

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