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V-Doubler Charge Pump

Assembled Module

© 2000-2017 Jack Orman

The charge-pump voltage booster module. Fully assembled and ready for installation in your pedal or project. Boosts 9v DC to almost 18v. The modules are made in the USA from domestic and foreign parts.

With a very light load, the output voltage may be close to 18v with a 9v input, but as the load is increased, the output voltage drops. With a 20 ma. load on the output, it measured 16.35 volts. This is common with all charge pump circuits.

V-Doubler Charge Pump

The voltage doubler module wiring diagram is shown here. The input voltage connections are on the left and the output are on the right. The Ground pads are connected together on the pcb. If the circuit is used inside a pedal, only one ground connection from the pcb to the original circuit is required.

Never connect more than 12 volts to the input to avoid damaging the charge pump chip.

The pc board measures 1.3" x 0.9" (33.0mm x 22.9mm) and is sized to fit into the Hammond 1590A aluminum box. The power jacks may be mounted in the ends of the box. Other enclosures and power jacks may be used as desired, and the board may even be mounted inside a pedal to provide higher voltage to the unit. Powering boosters with a higher voltage gives more clean headroom and the AMZ Voltage Doubler works well in this application.

The AMZ Voltage Doubler may be used as a positive to negative voltage converter. This is convenient to provide a negative voltage from a power adapter that does not have that feature. Many fuzzfaces, tonebenders, boosters and other PNP transistor circuits are positive ground and require a negative voltage supply. The pad marked with the minus sign is the 9v negative output, and does not have to be connected unless needed. The same goes for the +18v output, which can be left unconnected when not required.

This diagram shows center-negative connections (input jack) to the back of the common 2.1mm power supply jack as used on most pedals. Only two of the lug connections are used and the third one is left empty. On the output jack, the lug marked 9v on the diagram would be the 18v (V++) connection.

On this 2.1mm Kobiconn DC power jack, the wires would be connected to the brass tabs as 9v, no connection, ground (left to right in the photo).

If you prefer to build a voltage doubler on a through-hole pcb and supply your own parts, a ready-to-solder pc board is also available on the catalog page.

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