Power supply circuit » Converters

DC Voltage Doubler Circuit

aPowerSupply.com — Tue, 03 Jan 2012 03:56:33 +0000

This is a cheap DC Voltage Doubler Circuit diagram, which requires a few components and will deliver 10V from a 5V power supply. If the oscillator must be built from a non-functional gate then is required 2 more components: R1 and C3.

The most important parameters of this voltage doubler circuit are given in the table below. Note that because of the IC tolerances these data may have some differences.

Voltage doubler circuit diagram

AC DC Converter Circuit

aPowerSupply.com — Mon, 02 Jan 2012 03:35:51 +0000

This AC to DC converter circuit is capable to convert an alternative voltage from 70 – 260 Vac into a DC voltage from 180 to 250 Vdc.
To achieve this convertion we use a rectifier MC34161 as a voltage doubler at low input voltages and as a classic rectifier at high input voltages.

MC34161 includes a reference power supply which delivers 2.54V at pin 1. The signal level applied at pin 2 is internally compared with a 1.27V voltage.
D5 zener diode, togheter with R1 and C4 provide IC’s required 12V voltage. Capacitor’s voltage of C2 and C3 must be > 250V.

Attention: this ac to dc converter contains very high voltages and you must be careful!

Output DC voltage/Input AC voltage

AC to DC converter circuit diagram

Single chip voltage converter

aPowerSupply.com — Tue, 20 Dec 2011 23:25:00 +0000

With HV4205E you can build a simple single chip voltage converter. With IC and a few external components connected like in the schematic you can obtain dc stabilized voltages between 5 to 24V directly from main power source (100 to 260V ac). The maximum output current is 50mA.
The main chip contains a preregulator which ensure C2 charging voltage (a large capacitance). The charging process continues untill the capacitor voltage has reached a level of approximately the desired voltage + 6V.
When this stage is reached, C2 delivers the required voltage to the regulator, the output of this regulator can be adjusted between 5V and 24V with P1 and is available at IC pin 6.

Attention!
Because this circuit is coupled directly to the main supply do not touch any part of it!

Voltage converter schematic

6v to 12v converter TDA2003

aPowerSupply.com — Sat, 17 Dec 2011 21:57:22 +0000

This 6V to 12V converter circuit is made with an IC from SGS with several additional components. The IC is a TDA2003 but it can be replaced with a TDA2002. The cost of building the 6volts to 12 volts converter should be low enough to justify constructing it instead of modifying the entire equipment setup to work directly with a 6 volts power supply. The two principles of simplicity and functions properly without the need of the transformer.

The IC1 opam functions as a stable power multivibrator. Its oscillation frequency is determined by C3. Its oscillates at around 4kHz at standby and increases in a loaded condition up to around 7kHz. The output of the IC2 opamp is identical to the IC1 oscillator signal but in the opposite phase.

When the output of IC1 is at zero, the C4 charges via the diode D1 up to the power supply level minus the voltage drop at D1. When the IC1 swings to the opposite direction, its output become positive. The output voltage from IC1 adds up to the voltage stored at C4 forcing the diode D1 to stop conducting. C5 then charges via the diode D2 to a voltage that is double than the power supply level.

The theoritical output could reach the triple of the supply voltage. TO guard against unnecessary voltage increases at low current consumptions, a limiter stage was added to the circuit composed of a 15 volt zener diode and a darlington transistor T1/T2. This stage caps the output voltage to about 14.2 volts. To fiter out ripple from the output, C8 was also added. This helps prevent the hum signal from being noticed on radio or audio devices.

In constructing the 6 to 12 volts converter, attach the ICs to a common heatsink close to the pcb. THe transistor must be attached to a separate heatsink. To get a much higher current output from the converter, C4, C5 and C6 must be increased to 2200uF.

6 to 12 volts converter schematic

6v to 12v converter pcb layout

Converter 12V dc – 220V ac

aPowerSupply.com — Thu, 15 Dec 2011 21:16:32 +0000

This converter has a central component, the CMOS 4047, and converts a 12V DC voltage to 220V AC voltage. 4047 is utilised as a astable multivibrator. At pin 10 and 11 we find a rectangular symmetrically signal which is amplified by tow Darlington transistors T1 and T2 and finally reaches the secondary coil of a transformer network (2 x 10V/60VA). Primary coil terminals voltage is 220 alternative voltage. To obtain a better performance use a toroidal core transformer with reduced losses. With P1 the output frequency can be regulated between certain limits (50…400Hz).

12/220V Converter circuit schematic

Voltage Converter with TL497A

aPowerSupply.com — Fri, 07 Oct 2011 18:53:45 +0000

This voltage converter is built with TL497A and converts an input voltage of 5…12 voltage to a higher level of 15…30 volts. This is specially helpfull in mobile applications where power supply levels are commonly limited to 12 volts supplied by batteries.

The voltage converter circuit uses the TL497A as a flyback-voltage converter. The choke coil is 40uH/2A. Capacitors C2 annd C1 suppress voltage spikes. The maximum output current depends on the difference between the input and the output voltages and is around 100mA. The ripple voltage is relatively low. The standby current is around 8mA and the efficiency is about 70%.