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NR421A

Data Sheet(2.0MB)


Package Image

Package：HSOP8

The NR421A is Synchronous Rectification buck regulator ICs integrates PowerMOSFETs. With the current mode control, low ESR capacitors such as ceramic capacitors can be used. It has achieved a high efficiency by the synchronous rectification system. The ICs have protection functions such as Over-Current Protection (OCP), Under-Voltage Lockout (UVLO) and Thermal Shutdown (TSD). Soft starting time can be set up by selecting an external capacitor value. The ON/OFF pin (EN Pin) turns the regulator ON/OFF. The NR421A is available in an 8-pin HSOP package with an exposed thermal pad on the back side.

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Calculation Tools

NR421A Calculation Tool: DT0023

Features

    ・For excellent heat dissipation, HSOP8 package with the
        heat-slug is adopted.
    ・Current mode PWM control
    ・Up to 94% efficiency
    ・Stable with low ESR ceramic output capacitors
    ・Built-in protection function
       Drooping type Over Current Protection (OCP) with Auto-
       restart
       Thermal Shutdown (TSD) with Auto-restart
       Under Voltage Lockout(UVLO)
    ・By the internal Phase Compensation, external component
        count reduction

Application

    ･LCD TV / Blu-ray /Power supply for digital consumer
    ･Up to 94% efficiency Synchronous rectification system
    ･Current mode PWM control
    ･By the internal Phase Compensation, external component
      count reduction
    ･Stable with low ESR ceramic output capacitors

Specifications

Built-in Power Power IC
Output Method Variable
Output Voltage 14.0 V
Output Current 3.0 A
Input Voltage Range 4.5 to 18 V
Operating Frequency 350 kHz
Synchronous / Asynchronous Synchronous
Current Mode Control YES
Maximum Input Voltage 18.00 V
Output On / Off YES
Low ESR Capacitor Support YES
Overcurrent Protection Drooping Type
Phase Compensation Built-in
Thermal Protection YES
UVLO YES
Package Weight (Typ.) 0.081 g

Remarks

*This product is not pin compatible with NR885E.
*This product is not a replacement product of NR885E.

Typical Application

Typical Application

Block Diagram

Block Diagram

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