STMicroelectronics | L4978D

The L4978D is a step down monolithic power switching regulator delivering 2A at a voltage between 3.3 V and 50 V (selected by a simple external divider). Realized in BCD mixed technology, the device uses an internal power D-MOS transistor (with a typical Rdson of 0.25Ω) to obtain very high efficency and high switching speed.

Switching frequency up to 300 kHz is achievable (the maximum power dissipation of the packages must be observed). A wide input voltage range between 8 V to 55 V and output voltages regulated from 3.3 V to 50 V cover the majority of today’s applications.

Features:

• Up to 2 A Stepdown Converter
• Operating input voltage from 8 V to 55 V
• Precise 3.3 V (±1%) Internal Reference voltage
• Output voltage adjustable from 3.3 V to 50 V
• Switching frequency adjustable up to 300 kHz
• Voltage feedforward
• Zero load current operation
• Internal current limiting (Pulsebypulse and hiccup mode)
• Inhibit for zero current consuption
• Protection against feedback disconnection
• Thermal Shutdown
• Soft start function