Texas Instruments LM25119

Description

The LM25119 is a dual synchronous buck controller intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing anemulated current ramp. Current mode control provides inherent line feed-forward, cycle-by-cycle current limiting and ease of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications.The switching frequency is programmable from 50kHz to 750kHz. The LM25119 drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous mode operation for improved efficiency at light load conditions. A high voltage bias regulator with automatic switch-over to external bias further improves efficiency. Additional features include thermal shutdown, frequency synchronization, cycle-by-cycle and hiccup mode current limit and adjustable line under-voltage lockout. The device is available in a power enhanced leadless LLP-32 package featuring an exposed die attach pad to aid thermal dissipation.

Features

• LM25119Q is an Automotive Grade product that is AEC-Q100 grade 1 qualified (-40°C to 125°C operating junction temperature).
• Emulated peak current mode control
• Wide operating range from 4.5V to 42V
• Easily configurable for dual outputs or interleaved single output
• Robust 3.3A peak gate drive
• Switching frequency programmable to 750kHz
• Optional diode emulation mode
• Programmable output from 0.8V
• Precision 1.5% voltage reference
• Programmable current limit
• Hiccup mode overload protection
• Programmable soft-start
• Programmable line under-voltage lockout
• Automatic switch-over to external bias supply
• Channel2 enable logic input
• Thermal Shutdown
• Leadless LLP32 (5mm x 5mm) package

Typical applications

• Step-down regulator applications

More information

• Datasheet
• IC product information