LM25116MH

LM25116MH Application Field and Working Principle

The LM25116MH is a synchronous buck DC-DC switching controller designed to operate in continuous conduction mode. It is ideal for high-current, low-voltage battery or supply applications. The device integrates a pulse width modulation (PWM) comparator, an error amplifier, an internal high-side and low-side MOSFET driver, an operational amplifier, and several logic-level inputs.

The LM25116MH DC-DC switching controller requires a high-current power supply to be connected to the VCC pin for its operation. The PWM comparator and logic-level inputs allow the user to adjust the desired output voltage by adjusting the externally applied ramp signal. The error amplifier compares the reference voltage from the external resistors to the feedback voltage from the output of the power supply.

If there is an error between the reference voltage and the feedback voltage, the error amplifier drives the PWM comparator and then the PWM comparator triggers the MOSFET driver to switch the MOSFET on and off. This switching action is what converters the high-voltage DC source into the required output voltage.

The LM25116MH provides several advanced features that reduce one MTBF, voltage droop, and overall system complexity such as a constant-on time (COT) control, line UVLO, and soft start. The adjustable switching frequency also allows easy optimization of the system size by controlling the external inductor and capacitor values.

The LM25116MH is ideal for applications such as LED lighting, VoIPP, point of load (POL) converters, and battery backup systems, where the power supply voltage ranges from 5V to 30V, the output voltage ranges from 0.9V to 5V, and the output current ranges from 0A to 12A.