Description
The 6 to 75 V wide input voltage range STEVAL-L3751V12 synchronous buck
evaluation board features an extreme voltage conversion ratio over switching
frequency.
The board provides a regulated 5 V output at 230 kHz switching frequency. The
output voltage can be easily set to 12 V using a jumper connector. Different voltage
output can be selected by changing a resistor to a lower VIN range.
The STEVAL-L3751V12 is a 100 W demo board. The default maximum current is set
to 15 A. It can be easily selected by changing a resistor.
The evaluation board is based on the L3751 synchronous buck controller, which
implements the voltage mode in a VQFN package with internal compensation to
minimize the design complexity and size.
The diode emulation (DEM) implements the pulse-skipping mode, which maximizes
the efficiency at light-load with a 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. It implements the output voltage sequencing for digital ICs during the
power-up phase.
The embedded gate driver is designed for standard Vth MOSFET and minimizes the
number of external components.
The embedded protections, such as the output overcurrent, the input voltage UVLO,
the internal voltage monitoring, and the thermal shutdown at 150°C degrees, feature
a controlled and safe operation for critical environments in telecom, networking, and
industrial applications.
You can use the eDesignSuite software tool to configure the L3751 buck converter
and satisfy the application requirements.

Features
• 6 to 75 V wide input voltage range
• Selectable two-output voltage level: 5 V or 12 V
• 230 kHz switching frequency setting
• Low drop-out operation during line transient
• Pulse skipping or forced PWM operation at light load
• Synchronization from 185 to 345 kHz
• Power good open collector output validates the VOUT
• 7.5 V gate drivers for standard VTH MOSFETs
• Constant current protection with hiccup mode
• Current sensing on rds-on low-side
• Improved line-transient response
• Input voltage undervoltage lockout
• Internal voltage monitoring
• Thermal protection
• Operating junction temperature range: -40 to 150°C