Pololu 6V, 500mA Step-Down Voltage Regulator D24V5F6 Overview Pololu step-down voltage regulator D24V5Fx next to a 7805 voltage regulator in TO-220 package. The D24V5Fx family of buck (step-down) voltage regulators generates lower output voltages from input voltages as high as 36 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 93%, which is much more efficient than linear voltage regulators, especially when the difference between the input and output voltage is large. These regulators have a power-save mode that activates at light loads and a low quiescent (no load) current draw, which make them well suited for low-power applications that are run from a battery. These regulators are available in eight different fixed output voltages: The different versions of this regulator all look very similar, so the bottom silkscreen includes a blank space where you can add your own distinguishing marks or labels. This product page applies to all four versions of the D24V5Fx family. The regulators feature short-circuit/over-current protection, and thermal shutdown helps prevent damage from overheating. The boards do not have reverse-voltage protection. If you need more output current, consider our D15V35F5S3 and D15V70F5S3 3.3V/5V step-down voltage regulators, which can typically deliver a continuous 3.5 A and 7 A, respectively. Features Input voltage: 3 V to 36 V for output voltages of 1.8 V and 2.5 V output voltage + dropout voltage to 36 V for output voltages of 3.3 V and higher (see below for more information on dropout voltage) Fixed 1.8 V, 2.5 V, 3.3 V, 5 V, 6 V, 9 V, 12 V, or 15 V output (depending on regulator version) with 4% accuracy Maximum output current: 500 mA Typical efficiency of 80% to 93% 500 kHz switching frequency (when not in power-save mode) 200 A typical no-load quiescent current Integrated over-temperature and over-current shutoff Small size: 0.5 0.4 0.1 (13 mm 10 mm 3 mm) Using the regulator Connections The buck regulator has four connections: shutdown (SHDN), input voltage (VIN), ground (GND), and output voltage (VOUT). The SHDN pin can be driven low (under 0.4 V) to turn off the output and put the board into a low- power state. There is a 100 k pull-up resistor between the SHDN pin and VIN, so if you want to leave the board permanently enabled, the SHDN pin can be left disconnected. While the SHDN pin is being driven low, the current draw of the regulator is dominated by the current through the pull- up resistor and will be proportional to the input voltage. (At 36 V in it will draw about 360 A.) The input voltage, VIN, powers the regulator. Voltages between 3 V and 36 V can be applied to VIN, but for versions of the regulator that have an output voltage higher than 3 V, the effective lower limit of VIN is VOUT plus the regulators dropout voltage, which varies approximately linearly