December 29, 2024 
Professional magazine and portal dedicated to electronics 
With compact dimensions and an input-voltage range from 6V to 75V, STMicroelectronics’ L3751 synchronous buck controller serves different applications from industrial equipment to battery powered light electric vehicles. The 3.5mm x 4.5mm controller is also suited to use in telecom and networking equipment that feature commonly used 24V and 48V buses.
Having minimum on-time duration of 40ns, the L3751 can support an extremely low duty cycle thereby permitting a large step-down ratio. This allows powering low-voltage devices directly without intermediate conversion, which helps simplify circuit design and lower bill-of-materials (BOM) costs. The device integrates a 7.5V supply for the gate drivers.
In addition to having a wide supply-voltage range, the L3751 has 100V-tolerant inputs that allow operation in harsh electrical environments. The switching frequency is adjustable from 100kHz to 1MHz, giving designers flexibility to optimize circuit size, performance, and cost, through selection of the external MOSFETs and passive components (more info).
