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The MP2012 is a fully integrated, internally compensated 1.2MHz fixed frequency PWM step-down 

converter. It is ideal for powering portable equipment that runs from a single cell Lithium-Ion (Li+) Battery, 
with an input range from 2.7V to 6V. The MP2012 can provide up to 1.5A of load current with output voltage 

as low as 0.8V. It can also operate at 100% duty cycle for low dropout applications. With peak current mode 

control and internal compensation, the MP2012 is stable with ceramic capacitors and small inductors. Fault 
condition protection includes cycle-by-cycle current limiting and thermal shutdown.



2.7-6V Input Operation Range



Output Adjustable from 0.8V to VIN



1μA Max Shutdown Current.



Up to 95% Efficiency



100% Duty Cycle for Low Dropout



Applications



1.2MHz Fixed Switching Frequency



Stable with Low ESR Output Ceramic



Capacitors



Thermal Shutdown



Cycle-by-Cycle Over Current Protection



Short Circuit Protection



Available in 6-pin 3x3mm QFN

1

FB

Feedback input. An external resistor divider from the output 
to GND, tapped to the FB pin sets the output voltage.

2

GND, Exposed 

Pad

Ground pin. Connect exposed pad to ground plane for 

proper thermal performance.

3

SW

Switch node to the inductor.

4

PVIN

Input supply pin for power FET.

5

VIN

Input Supply pin for controller. Put small decoupling 

ceramic near this pin.

6

EN

Enable input, “High” enables MP2012. EN is pulled to GND 
with 1Meg internal resistor.

17.3

17.2

17.1

The RT8283A is a high-efficiency, monolithic synchronous step-down DC/DC converter that can deliver up 

to 3A output current from a 4.5V to 23V input supply. The RT8283A's current mode architecture and 
external compensation allow the transient response to be optimized over a wide range of loads and output 

capacitors. Cycle-by-cycle current limit provides protection against shorted outputs and soft-start eliminates 

input current surge during start-up. The RT8283A also provides output under voltage protection and thermal 
shutdown  protection.  The  low  current  (<3μA)  shutdown  mode  provides  output  disconnect,  enabling  easy 

power management in battery powered systems. The RT8283A is available in a SOP-8 package.



±1.5% High Accuracy Feedback Voltage



Integrated N-MOSFET Switches



Current Mode Control



Fixed Frequency Operation : 340kHz



Output Adjustable from 0.8V to 20V



Up to 95% Efficiency



Thermal Shutdown Protection

18.2

18.1

BOOT

Bootstrap for high-side gate driver. Connect a 0.1

μF or 

greater ceramic capacitor from BOOT to SW pins.

VIN

Input Supply 4.5V to 23V. Must bypass with a suitably 
large ceramic capacitor.

SW

Phase Node--Connect to external L-C filter..

GND

Ground. 

FB

Feedback Input pin is connected to the converter output. 
It is used to set the output of the converter to regulate to 

the desired value via an internal res divider. For an 

adjustable output, an external res divider is connected to 

this pin.

COMP

Compensation Node. COMP is used to compensate the 
regulation Control loop. Connect a series RC network 

from COMP to GND. In some cases, an additional 

capacitor from COMP to GND is required.

EN

Enable Input Pin. Logic high enables the converter; a 

logic low forces the RT8253A into shutdown mode. 

Attach this pin to VIN with a 100kΩ pull up resistor for 

automatic startup. 

SS

Soft-Start Control Input. SS controls the soft-start period. 
Connect a capacitor from SS to GND to set the soft-start 
period. A 0.1

μF capacitor sets the soft-start period to 

13.5ms.

18.3

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. 

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 

19.3

19.2

19.1