Simple 6V to 12V Converter Circuit (High Current)

This post shows you how to build a little helper circuit that can take a 6V battery and turn it into a 12V power source.

This is useful for electronics that need 12V to work, like some motors or toys.

This special circuit can provide more power current than some other converters, so it can be used for things that need a bit more juice.

Circuit Working:

Parts List:

This voltage converter circuit, ranging from 6V to 12V, utilizes an IC manufactured by SGS along with several supplementary components.

The primary IC employed is the TDA2003 although it can be substituted with a TDA2002.

The construction cost of this converter is intended to be economical enough to justify its assembly rather than modifying the entire equipment setup to accommodate a direct 6V power supply.

The design prioritizes simplicity and functionality eliminating the need for a transformer.

The initial IC, designated as IC1 operates as a stable power multivibrator.

Its oscillation frequency is dictated by the capacitor C3 hovering around 4kHz during standby and rising to approximately 7kHz under load.

Meanwhile, the output signal of IC2 mirrors that of IC1 but in an inverted phase.

During IC1s output at zero, capacitor C4 charges through diode D1 up to the power supply level minus the voltage drop across D1.

As IC1 shifts polarity its output becomes positive causing the voltage from IC1 to add up to the charge stored at C4 halting diode D1 conduction.

Subsequently, capacitor C5 charges via diode D2 to a voltage double that of the power supply level.

The theoretical output could potentially triple the supply voltage.

To prevent unnecessary voltage escalation at low current consumption a limiter stage has been integrated into the circuit comprising a 15V zener diode and a darlington transistor T1 and T2.

This stage confines the output voltage to around 14.2V.

Additionally, capacitor C8 has been incorporated to filter out ripple from the output ensuring that any hum signals are suppressed particularly on radio or audio devices.

During construction of the 6 to 12V converter, it is advisable to affix the ICs onto a common heatsink in close proximity to the PCB while the transistor necessitates a separate heatsink.

For a substantially higher current output from the converter, capacitors C4, C5 and C6 should be increased to 2200uF.

Formulas and Calculations:

You may use capacitors and diodes organized in a way that efficiently doubles the input voltage to convert 6V to 12V using a voltage doubler circuit.

An approximation for the output voltage of a voltage doubler circuit is as follows:

V_out ​= 2 * V_in​ − V_diode​

where:

• V_out is the output voltage.
• V_in is the input voltage 6V in our circuit.
• V_diode​ is the forward voltage drop across each diode.

Example Calculation:

Assume:

V_in = 6V

V_diode (typical forward voltage drop of silicon diodes) = 0.7V (for each diode)

V_out = 2 * 6V − 2* 0.7V

V_out ​= 12V − 1.4V

V_out​ = 10.6V

The actual output voltage may differ somewhat owing to component tolerances and losses, this is a simplified calculation.

It does, however, provide a decent estimate of the anticipated output voltage.

You may effectively create a 6V to 12V voltage doubler circuit by comprehending and using the voltage doubling formula as well as taking the properties of the components into account.

Based on your unique needs and the demands of your application, change the settings and configurations of the components.

How to Build:

To build the 6V to 12V voltage converter circuit below mentioned are the steps:

Prepare the PCB:

• Design or obtain a PCB layout for the circuit.
• Place appropriate markings for component placement and solder points.

Component Placement:

• Mount the TDA2003 or TDA2002 ICs onto a common heatsink in close proximity to the PCB.
• Affix the Darlington transistor T1 and T2 to a separate heatsink.
• Place capacitors C3, C4, C5, C6 and C8 onto the PCB at their designated positions.
• Install diodes D1 and D2 as per the circuit diagram.
• Position the zener diode 15V appropriately on the PCB.

Soldering:

• Solder each component onto the PCB according to the circuit diagram.
• Ensure proper connections and avoid solder bridges.

Testing and Adjustment:

• Before connecting to power, double check all solder joints for any errors or shorts.
• Connect a 6V power supply to the input terminals of the circuit.
• Using a multimeter measure the output voltage across the appropriate terminals.
• Ensure it is around 12V.
• If needed, adjust component values or troubleshoot any issues.
• Verify that the output voltage does not exceed the desired limit around 14.2V after incorporating the limiter stage.

Finalization:

• Once testing is successful and the circuit operates within desired parameters finalize the connections.
• Mount the PCB securely within the equipment setup where it will be utilized.
• Ensure proper insulation and safety measures are in place.

Note:

• Following these steps carefully should result in the successful construction of the 6V to 12V voltage converter circuit.
• If any difficulties arise during the process consult the circuit diagram and datasheets of the components used for further assistance.

Conclusion:

These circuits are often used in automotive applications, portable electronic devices, power supplies for industrial equipment and various other scenarios where a reliable and efficient voltage conversion with high current capability is necessary.

References:

Is it possible to convert 6V 4A (24W) DC to 12V 3A (36W) DC using step up booster?