R1272 Series
34V Input PWM/VFM Step-down DC/DC Controller with PLL Synchronization

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  • Description

    The R1272 is a step-down DC/DC controller with synchronous rectifier and 34V input voltage. By the adoption of a unique current mode PWM architecture without an external current sense resistor, the R1272 can make up a stable DC/DC converter with high-efficiency even if adding low Ron MOSFETs and a low DCR inductor externally. In PLL_PWM mode, oscillator frequency is synchronized to an external clock frequency using a PLL and is effective for EMI control. For EMI reduction, SSCG (Spread-Spectrum Clock Generation) for diffused oscillation frequency at the PWM operation is optionally available.

  • Spec
    Consumer Industrial Automotive
    Input Voltage Range 4.0 V to 34.0 V (36.0 V)
    Operating Temperature Range -40°C to 105°C (125°C) -40°C to 105°C (125°C) -40°C to 125°C (150°C)
    Supply Current Typ. 15 µA
    Standby Current Typ. 3 µA
    Start-up Voltage 4.5 V
    Output Voltage Range Externally Adjustable: 0.7 V to 5.3 V
    Feedback Voltage 0.64 V
    Feedback Voltage Accuracy ±1%
    Oscillator Frequency Externally Adjustable: 250 kHz to 1 MHz
    Package HSOP-18

    Protections / Functions

    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 (at 1MHz)

      Typical Application
    • Efficiency vs. Output Current

      Efficiency vs. Output Current

    • Related Links

      • Prime Designer

        Online Design Tool

        Registration to myNISD is required to use some of the functions, such as simulations.

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  • Quality &
    Packages
    • Refer to the datasheets for the details on the product.
    • The package file or the datasheet includes package dimensions, taping specifications, taping reels dimensions, power dissipations, and recommended land pattern.

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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

Search for similar products under conditions below.

Category:DC/DC Switching Regulators

Topology Buck
VIN
min (V)
4.0
VIN
max (V)
34.0
VOUT
min (V)
0.7
VOUT
max (V)
5.3
ISS
(µA)
15