The RAA211805 is a tiny, easy-to-use, ultra-low quiescent current (IQ) buck regulator with a wide input voltage range of 7V to 80V and up to 300mA of output current with a fixed 5V output.

Available in a TSOT23-5 package, the device offers comprehensive protections, including VIN undervoltage lockout (UVLO), VOUT overvoltage protection (OVP), overcurrent protection, and over-temperature protection.


  • 7V to 80V input supply range
  • Up to 300mA output current
  • IQ = 5.5μA at 80V, at no load conditions, switching
  • IQ = 4.5μA at 80V at no load and no switching conditions
  • Fixed 5V VOUT
  • Minimum on-time of 75ns
  • Variable frequency operation, frequency programmed by external inductor (10μH to 33μH)
  • Pre-bias, monotonic, and smooth start-up
  • Protections
    • Overcurrent (OC) limit
    • Input undervoltage lockout (UVLO)
    • Over-temperature protection (OTP)
    • Output overvoltage protection (OVP)
  • Accurate EN threshold
  • Package: TSOT23-5 (2.9mm x 1.63mm)




  • General-purpose or LDO replacement
  • Industrial power supplies
  • Embedded systems and I/O supplies
  • E-bikes
  • power tools
  • Home/Industrial automation


Type Title Date
Datasheet PDF 4.35 MB
Brochure PDF 5.49 MB 日本語
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Design & Development

Boards & Kits

Boards & Kits


Portfolio of High Performance, Low Iq Buck Regulators for LDO Replacement

The RAA21140x and RAA21180x families of bucks are simple to use and cost-effective while offering more than 15x less power loss of similar output rating LDOs (depending on operating conditions) with ultra-low 4uA Iq at zero loading conditions, making it ideal for powering always-on standby housekeeping MCUs or sensors. These bucks are ideal for general LDO replacement in applications such as industrial & home automation, eMobility solutions, energy storage, cordless power tools, and appliances.