Quad Power Supply




Circuit Diagram

The quad supply is a small simple unit designed to provide a complete power source for analogue/digital circuits under test.
It replaces several large, heavy, expensive mains powered supplies yet is only five inches wide by four deep by two high.

It provides outputs of +/-9V and +/-5V at low currents for powering experimental electronic circuits.
The +9V supply comes direct from a PP3 battery and the -9V is produced by a TC1044S flying capacitor voltage inverter.
The +5V is derived from +9V via a 78L05 regulator, and the -5V comes from -9V via a 79L05 negative voltage regulator.

In normal use the +/-9V terminals power analogue circuits such as opamps and the +5V terminal powers CMOS logic circuits.
Other voltages can be derived, for example 18V from the +/-9V terminals or 10V regulated from the +/-5V terminals.

Output current from +9V is whatever the battery can provide. Current capability from +5V is approximately 50mA.
The -9V and -5V terminals can supply a total of 20 mA with a drop of 1V in the -9V supply. If -9V is not used,
the -5V terminal can supply up to 40 mA.



Circuit Board Layout

The circuit board layout is quite relaxed with very few components to place



Front Panel

The front panel carries the five output terminals -9V -5V 0V +5V +9V.



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