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R1271 Series

30 V, 1 A Synchronous PWM Step-down DC/DC Converter

  • Consumer
  • Industrial
  • Automotive
  • PLP
  • RoHS

The R1271 is a synchronous step-down DC/DC converter with a maximum input voltage rating of 42 V. This device is suitable for small inductors with the switching frequency of 2 MHz. The external components are only an inductor and several capacitors and a resistance. The tiny DFN package option makes the power circuit compact.

  • High efficiency 85% is realized with switching frequency of 2 MHz
  • The output voltage is maintained at cranking by reducing a switching frequency to minimum 1/4 of normal frequency.
  • EMI noise reduction by using a spread spectrum clock generator. (Diffusion Rate: +10%).

Specs & Datasheets

  Consumer Industrial Automotive
Input Voltage Range 3.6 V to 30.0 V (42.0 V)
Operating Temperature Range -40°C to 105°C (125°C) -40°C to 125°C (150°C) -40°C to 125°C (150°C)
Supply Current Typ. 1 mA
Standby Current Typ. 4 µA
Start-up Voltage 4.5 V
Output Voltage Range 3.3 V, 5.0 V
Output Voltage Accuracy ±1.0% (Ta = 25°C)
Output Current 1 A
Driver ON-resistance HIgh side: Typ. 0.4 Ω, Low side: Typ. 0.2 Ω
Oscillator Frequency Typ. 2 MHz
Package DFN3030-12B, HSOP-18

Download Datasheet

Protections / Functions

Functional Description

TSD ILX OCP OVP UVLO OVLO Reverse Shutdown Soft Start SSCG PGOOD Auto Discharge Anti-ringing Sequencing Max Duty Ext. Phase LED Adjust

Technical Documents

Typical Application

Typical Application

DFN3030-12B PCB Example

DFN3030-12B PCB Example

Introduction Video

Quality & Packages

Product Name Compatibility Package Marking Reliability
  • gradeConsumerC
DFN3030-12B R1271L R1271L
  • gradeConsumerC
  • plpP
HSOP-18 R1271S R1271S-FE
  • gradeIndustrialI
DFN3030-12B R1271L R1271L-Y
  • gradeIndustrialI
  • plpP
HSOP-18 R1271S R1271S-YE
  • gradeAutomotiveA
DFN3030-12B R1271L R1271L-A
  • gradeAutomotiveA
DFN3030-12B R1271L R1271L-K
  • gradeAutomotiveA
  • plpP
HSOP-18 R1271S R1271S-AE
  • gradeAutomotiveA
  • plpP
HSOP-18 R1271S R1271S-KE

Refer to the datasheets for the details on the product.
The package file includes package dimensions, taping specifications, taping reels dimensions, power dissipations, and recommended land pattern.
Please contact us or our distributors for unpublished reliability information.

Sample / Buy

Functional Description

TSD Thermal Shutdown Function
ILX LX Current Limit Function
OCP Overcurrent Protection
OVP Overvoltage Protection
UVLO Undervoltage Lockout Protection
OVLO Overvoltage Lockout Protection
Reverse Reverse Current Protection Circuit
Shutdown Shutdown Function
Soft Start Soft Start Function
SSCG Spread Spectrum Clock Generator Function
PGOOD Power Good Output
Auto Discharge Auto Discharge Function
Anti-ringing Anti-ringing Switch Function
Sequencing Start-up Sequencing Control
Max Duty Maximum Duty Cycle
Ext. Phase Externally Adjustable Phase Compensation
LED Adjust LED High-speed Dimming Control

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