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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 
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enabling easy power management in batterypowered systems. The RT8283A is available 
in a SOP-8 package.

x

±1.5% High Accuracy Feedback Voltage

x

Integrated N-MOSFET Switches

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Current Mode Control

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Fixed Frequency Operation : 340kHz

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Output Adjustable from 0.8V to 20V

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Up to 95% Efficiency

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Thermal Shutdown Protection

1

BOOT

Bootstrap for high-side gate driver. Connect a 0.1

˩F or 

greater ceramic capacitor from BOOT to SW pins.

2

VIN

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

3

SW

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

4, 9 (Exposed 

Pad)

GND

Ground. 

5

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.

6

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.

7

EN

Enable Input Pin. Logic high enables the converter; a 
logic low forces the RT8253A into shutdown mode. 
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automatic startup. 

8

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

˩F capacitor sets the soft-start period to 

13.5ms.

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.

x

3A Output Current

x

Programmable Soft-Start

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Stable with Low ESR Output Ceramic Capacitors

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Up to 95% Efficiency

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Fixed 385KHz Frequency

x

Thermal Shutdown

x

Cycle-by-Cycle Over Current Protection

x

Wide 4.75V to 23V Operating Input Range

x

Output Adjustable from 1.22V to 21V

x

Under-Voltage Lockout

1

BOOT

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

2

IN

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

3

SW

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

4

GND

Ground.

5

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. 

6

COMP

Compensation Node is used to compensate the regulation control 
loop. 

7

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.

8

SS

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

This P-Channel 2.5V specified MOSFET is produced using Fairchild’s advanced 
PowerTrench® process that has been especially tailored to minimize on-state resistance 
and yet maintain low gate charge for superior switching performance. 

These devices have been designed to offer exceptional power dissipation in a very small 
footprint for applications where the larger packages are impractical.

x

0D[U'6 RQ PȍDW9 *6  -4.5 V, ID = -4.0 A

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0D[U'6 RQ PȍDW9 *6  -2.5 V, ID = -3.2 A

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Fast switching speed

x

Low gate charge (11nC typical) 

x

High performance trench technology for extremely low rDS(on)

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SuperSOTTM-6 package: small footprint (72% smaller than standard SO-8); 
low profile (1 mm thick)

x

Termination is Lead-free and RoHS Compliant

This P-Channel 1.8V specified MOSFET uses Fairchild’s low voltage PowerTrench 
process. It has been optimized for battery power management applications.

x

–5.5 A, –95'62 1  Pȍ#9*6 –4.5 V

x

5'6 2 1  Pȍ#VGS = –2.5 V

x

5'6 2 1  Pȍ#9 *6  –1.8 V

x

Fast switching speed.

x

High performance trench technology for extremely low RDS(ON)(S)