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Texas Instruments ATL431 Adjustable Precision Shunt Regulator

Texas Instruments ATL431 Adjustable Precision Shunt Regulator is a three-terminal adjustable shunt regulator, with specified thermal stability over applicable automotive, commercial, and industrial temperature ranges. The output voltage can be set to any value between Vref (approximately 2.5V) and 36V, with two external resistors. This device has a typical output impedance of 0.05Ω. Active output circuitry provides a very sharp turn-on characteristic, making these devices excellent replacements for Zener diodes. This can be done in many applications, such as on-board regulation, adjustable power supplies, and switching power supplies. Texas Instruments ATL431 has >20x improvement cathode current range over it's TL43x predecessor. It also is stable with a wider range of load capacitance types and values.

Features

  • 2.5V to 36V adjustable regulated output
  • Very-Low Operating Current
    • IKA(min) = 35µA (max)
    • IREF = 150nA (max)
  • Internally Compensated for Stability
    • Stable with no capacitive load
  • Reference Voltage Tolerances at +25°C
    • 0.5% for B grade
    • 1% for A grade
  • Typical Temperature Drift
    • 5mV (–40°C to +85°C); I version
    • 6mV (–40°C to +125°C); Q version
  • 35µA to 100mA extended cathode current range
  • 0.3Ω (max) low output impedance

Applications

  • Secondary side regulation in flyback SMPSs
  • Industrial, computing, consumer, and portables
  • Adjustable voltage and current referencing
  • Power management
  • Power isolation
  • Zener replacement
Published: 2015-06-23 | Updated: 2022-03-11