Data Sheet

RB-Fee-14
1A 28V Voltage Regulator
The PR28V is rated for up to 1A output and can be used to power your own circuit design and also
power our EtherTen, EtherMega and Ethernet Shield over the network cable by fitting the PR28V to
their dedicated pins ready for it. A very useful wide range switchmode regulator with a 5V or 7V output
and a wide range input of up to 28V.
The Power Regulator 28V can be used in two different ways:
1. As a Power-over-Ethernet voltage regulator, it mounts on our Ethernet Shield or EtherTen to allow
them to accept input voltages up to 28V via the network cable. If you only intend to pass about 10V
down the Ethernet cable you don't need this module: you can simply put a pair of jumpers across the
PoE header pins on the Ethernet Shield or EtherTen and let the Arduino on-board voltage regulator do
all the work.
If you want to push a higher voltage down the wires (perhaps you already have a 16V, 18V, or 24V
power supply lying around?) the Arduino voltage regulator will get very hot and unhappy, so this
regulator module takes the power you send down the cable and pre-regulates it down to 7V before
passing it through to your Arduino for the final drop to 5V.
This regulator module is designed for use with home-brew PoE injectors that typically supply 16V or
24V or our 4-Port PoE Midspan Injector, not commercial PoE switches.
2. As a general purpose switchmode voltage regulator, it can be configured to provide a regulated 5V or
7V output so that you can use it directly as a high-efficiency power supply for your projects.