LC-32SH130K (serv.man8). Circuit Descriptions - Sharp TV Service Manual (repair manual). Page 41

The MP1583 is a step-down regulator with a built-in internal Power MOSFET. It achieves 3A of continuous 
output current over a wide input supply range with excellent load and line regulation. Current mode 
operation provides fast transient response and eases loop stabilization. Fault condition protection 
includes cycle-by-cycle current limiting and thermal shutdown. An adjustable soft-start reduces the 
stress on the input source at start-up. The MP1583 requires a minimum number of external components, 
providing a compact solution.



3A Output Current



Programmable Soft-Start



100mΩ Internal Power MOSFET Switch



Stable with Low ESR Output Ceramic Capacitors



Up to 95% Efficiency



20μA Shutdown Mode



Fixed 385KHz Frequency



Thermal Shutdown



Cycle-by-Cycle Over Current Protection



Wide 4.75V to 23V Operating Input Range



Output Adjustable from 1.22V to 21V



Under-Voltage Lockout

BOOT

High-Side Gate Drive Bootstrap Input. BS supplies the drive for the 
high-side N-Channel MOSFET switch. 

IN

Power Input. Drive IN with a 4.75V to 23V power source. 

SW

Power Switching Out is the switching node that supplies power to the 

output

GND

Ground.

FB

Feedback Input. FB senses the output voltage and regulates it. Drive 
FB with a resistive voltage divider from the output voltage. FB 

threshold is 1.222V. 

COMP

Compensation Node is used to compensate the regulation control 
loop. 

EN

Enable/UVLO. A voltage greater than 2.71V enables operation. For 
complete low current shutdown the EN pin voltage needs to be at less 

than 900mV. When the voltage on EN exceeds 1.2V, the internal 

regulator will be enabled and the soft-start capacitor will begin to 

charge. The MP1583 will start  switching after the EN pin voltage 

reaches 2.71V.

SS

Soft-Start Control Input. SS controls the soft-start period. 

19.3

19.2

19.1