KIT 83

UNIVERSAL DUAL POLARITY 1 AMP POWER SUPPLY

Courtesy/Thanks to: www.kitsrus.com

Description: Many times the hobbyist wants to have a simple, dual
polarity DC power supply for a project. Existing power
supplies may be too big either in power output or physical
size. Just a simple power supply is required.
For most non-critical applications the best and simplest
choice for a voltage regulator is the 3-terminal type. The 3
terminals are input, ground and output. The 78xx & 79xx
series can provide up to 1A load current and it have onchip
circuitry to prevent damage in the event of over
heating or excessive current. That is, the chip simply shuts
down rather than blowing out. These regulators are
inexpensive, easy to use, and they make it practical to
design a system with many PCBs in which an unregulated
supply is brought in and regulation is done locally on each
circuit board.
This kit provides a dual DC power supply. With the
appropriate choice of transformer and 3-terminal voltage
regulator pairs you can easily build a small power supply
delivering up to one amp at +/- 5V, +/- 9V, +/- 12V, +/-
15V or +/-18V. You have to provide the centre tapped
transformer and the 3-terminal pair of regulators you want:
7805 & 7905, 7809 & 7909, 7812 & 7912, 7815 & 7915
or 7818 & 7918. We have provided the PCB and other
components necessary. Note that the + and - regulators do
not have to be matched: you can for example, use a +5v
and -9V pair. However, the positive regulator must be a
78xx regulator, and the negative a 79xx one.
We have built in plenty of safety into this kit so it should
give many years of continuous service. Voltage regulators
have not been supplied. The user must choose the pair he
needs for his particular application.