Skip to content

5V, 9A Step-Down Voltage Regulator D24V90F5

by Pololu
$25.49
SKU 1531

This synchronous switching step-down (or buck) regulator takes an input voltage of up to 38 V and efficiently reduces it to 5 V while allowing a typical continuous output current of up to 9 A. Typical efficiencies of 80% to 95% make this regulator well suited for higher-power applications like powering motors or servos, while high efficiencies are maintained at light loads by dynamically changing the switching frequency, and an optional shutdown pin enables a low-power state with a current draw of a few hundred microamps.

These high-current step-down (buck) regulators generate a fixed 5 V output from input voltages up to 38 V. They are switching regulators (also called switched-mode power supplies (SMPS) or DC-to-DC converters) and have a typical efficiency between 80% to 95%. The available output current is a function of the input voltage and efficiency (see the Typical Efficiency and Output Current section below), but the input current can typically be as high as 9 A.

The ENABLE pin can be used to put the board in a low-power state that reduces the quiescent current to approximately 10 µA to 20 µA per volt on VIN, and a PG (power good) indicator makes it easy to monitor the state of the main power for your system. The regulator's output voltage setting can also be lowered by adding an external resistor.

This regulator has built-in reverse-voltage protection, short-circuit protection, thermal shutdown (which typically activates at 160°C), a soft-start feature that reduces inrush current, and an under-voltage lockout that causes the regulator to turn off when the input voltage is below 4.2 V (typical).

  • Input voltage: 5 to 38 V 
  • Fixed 5 V output (with 4% accuracy); this can be lowered by adding an external resistor between FB and VOUT
  • Typical maximum continuous output current: 9 A
  • Integrated reverse-voltage protection, over-current protection, over-temperature shutoff, soft-start, and under-voltage lockout
  • Typical efficiency of 80% to 95%, depending on input voltage and load; the switching frequency automatically changes at light loads to maintain high efficiencies
  • 800 μA typical no-load quiescent current; can be reduced to 10 µA to 20 µA per volt on VIN by disabling the board
  • “Power good” output indicates when the regulator cannot maintain its set output voltage
  • Compact size: 1.6″ × 0.8″ × 0.3″ (40.6 × 20.3 × 7.6 mm)
  • Four mounting holes for #2 or M2 screws
  • Smaller holes for 0.1″ header pins and larger holes for terminal blocks offer several options for connecting to the board