LM25116MHX

• Peak current mode simulation
• Wide operating voltage range up to 42V
• Low I_Qshutdown" (
• Standard or logic level MOSFETs for the driver
• Powerful gate drive 3.5A peak
• Free-running or 1MHz synchronous operation
• Selectable diode emulation mode
• Programmable output 1.215V to 36V
• 1.5% accuracy voltage reference
• Programmable current limit
• Programmable soft-start
• Programmable input undervoltage lockout
• Automatic switching to an external bias supply
• TSSOP-20EP exposed pads are used
• Thermal shutdown

illustrate

The LM25116 is a synchronous buck controller intended for a wide range of applications from high voltage buck regulators to different input sources or intends. The control method is based on the current mode, using an analog current ramp control. Current-mode control provides inherent line feed-forward with periodic current limiting and loop compensation for easy cycling. The use of an analog ramp reduces the sensitivity of the pulse-width modulation circuit for noise control, allowing for very small duty cycles necessary for reliable control in high input voltage applications. Programmable operating frequency from 50kHz to 1MHz. External high-side and low-side NMOS power switches of the LM25116 driver with adaptive dead-time control. User-selectable diode emulation mode allows discontinuous mode operation to improve efficiency at light loads. The low quiescent current shutdown controller and disable consume less than 10μA of total input current. Other features include a high voltage bias regulator that automatically switches to external bias for efficiency, thermal shutdown, frequency synchronization, cycle-by-cycle current limit, and adjustable input undervoltage lockout. The device is available in an enhanced TSSOP-20 package with exposed pad attachment chip to help dissipate heat.