Simple Dual Output Voltage Doubler and Inverter Circuit

The Simple Dual Output Voltage Doubler and Inverter Circuit is really important for many power electronics uses that need either a higher voltage or a negative voltage from just one power source.

These circuits are especially helpful for things like changing DC to DC, battery powered devices and circuits that need low power voltage.

The special chip IC MAX660 used in this circuit needs very few extra parts and can handle a load current of up to 100mA.

The input voltage Vin can be between 1.5 and 5.5V DC but the load current should stay below 100mA.

This article explores a voltage doubler and inverter circuit that uses the MAX660 IC which is designed to create a negative voltage equal to the input voltage (-Vin) and a voltage that is about double the input voltage (2Vin – 1.4V).

Circuit Working:

Parts List:

The circuit in this article uses the MAX660 chip, which acts like a special voltage converter called a charge pump.

It works together with some capacitors and diodes to create the output voltages we want.

Let us understand the working of this circuit:

The IC MAX660 switches the capacitors inside it to flip the input voltage (+Vin) into an output voltage of -Vin.

Capacitor C1 is super important for the charge pumping, while capacitor C2 helps keep the inverted output voltage steady.

Diode D1 which is a 1N4148 type stops any reverse current from happening, making sure the charge moves correctly.

The next part of the circuit is made to double the input voltage.

Capacitor C3 gets charged up to Vin and then connects in series with Vin, which makes the voltage double.

Diode D2 helps move the charge to capacitor C4 smoothing out the doubled output voltage.

At this point the final output voltage is about 2Vin – 1.4V where the 1.4V is the total voltage drop from the two diodes.

Formulas with Calculations:

Below are the formulas and calculations for Simple Dual Output Voltage Doubler and Inverter Circuit:

Voltage Inversion Output Calculation:

The circuit inverts the input voltage using the MAX660 charge pump.

The ideal output for voltage inversion is given by:

Vout = -Vin

For example, if the input voltage Vin is 5V:

Vout = -5V

This means the circuit provides a negative output voltage equal in magnitude to the input voltage.

Voltage Doubling Output Calculation:

In an ideal voltage doubler circuit the output voltage is given by:

Vout = 2Vin

However, in this practical circuit two diodes D1 and D2 introduce a voltage drop.

Each diode 1N4148 has a typical forward voltage drop of approximately 0.7V.

Since there are two diodes in the circuit, the total voltage drop is:

Voltage drop = 0.7V + 0.7V = 1.4V

Thus, the actual output voltage for the doubler circuit is:

Vout = 2Vin – 1.4V

Example Calculation:

If the input voltage Vin is 5V:

Ideal output: 2 × 5V = 10V

Practical output: 10V – 1.4V = 8.6V

How to Build:

To build a Simple Dual Output Voltage Doubler and Inverter Circuit follow the below steps for connections:

• Gather all the components as mentioned in the above circuit diagram
• Connect pin 2 of IC1 to one terminal of capacitor C1 and other terminal of C1 connect to pin 4 of IC1
• Connect pin 3 and pin 6 of IC1 to GND of the circuit
• Connect pin 5 of IC1 to Vout = -Vin
• Connect capacitor C2 negative to end of pin 5 of IC1 and positive of C2 connect to GND
• Connect pin 8 of IC1 to +Vin
• Connect anode of diode D1 between pin 8 and anode of diode D2
• Connect negative of capacitor C3 from pin 2 of IC1 and positive of C3 connect anode of diode D2
• Connect positive of capacitor C4 between the junction of cathode of D2 and Vout = 2Vin-1.4 and negative of C4 connect to GND

Conclusion:

Simple Dual Output Voltage Doubler and Inverter Circuit acts as both a voltage doubler and an inverter giving you two different voltage outputs from just one power source.

This is really handy when you need different voltage levels for your projects.

The MAX660 IC charge pump chip makes it easier to build the circuit and cuts down on the number of inductors needed, which helps keep it small and efficient.

By choosing the right capacitors and diodes you can tweak the circuit to fit different power supply requirements in low power electronic projects.

References:

Voltage Doubler Design and Analysis