LM2576WT

The LM2576WT is a monolithic switching regulator series with a wide range of features, including adjustable output voltage ranging from 1.23v to 37v, adjustable switching frequency up to 1 MHz, and output power up to 3 A. It is rated for 2 A continuous at a junction temperature of up to 125 °C. This makes the LM2576WT suitable for automotive and other applications requiring extreme temperature operating conditions.

It is a pulse width modulation (PWM) controlled series of DC/DC converters, which are engineered to provide a highly regulated output voltage with excellent line and load regulation in a very small footprint. It is ideal for automotive, industrial, and consumer applications that demand high performance, reliability and efficiency.

The LM2576WT series includes two synchronous, step-down controllers with an integrated high-side P-channel MOSFET for use in buck regulator applications. The LM2576WT-ADJ is an adjustable voltage version with 3.2V to 37V output voltage range. The LM2576WT-12 is the 12V fixed output version. The single IC includes all of the functions needed to achieve a highly efficient, low-cost buck solution, including error amplifier, oscillator, on/off control logic, PWM comparator, current limit and thermal shutdown circuitry.

The converter operates in pulse width modulation (PWM) mode over a wide range of input voltage. When the output voltage falls below the reference voltage, the PWM comparator turns on the high side MOSFET. This allows energy to be transferred into an inductor thereby increasing the inductor\'s stored energy. When the voltage across the inductor reaches the reference voltage, the high side MOSFET is switched off and a diode is used to prevent the reverse flow of current into the input source.

The current limit function is used to protect the converter from over-current conditions. The current limit threshold value can be set with an external resistor connected to the LIM pin. The output voltage can be adjusted by changing the voltage on the VCO pin. The voltage range and switching frequency can also be changed using an external resistor and capacitor connected to the VCO pin. The internal current limit, thermal shutdown, and soft-start functions help to protect the converter from possible damage in the event of an overload or thermal shutdown condition.

The LM2576WT series of switching regulators produce excellent efficiency in a compact package size. The on/off control logic enhances the protection against possible undershoot and overshoot voltage conditions, allowing the device to operate in environments where input voltage transients are common. The flexibility and high performance of the LM2576WT makes it an ideal solution for automotive, industrial and consumer applications requiring low-cost and highly efficient DC/DC conversion.