Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 45,000+ electronic circuits, cross-referenced into 500+ categories.
We have searched the web to help you find quick solutions & design ideas.

Got Designs?
Please eMail
if you want me to link to and/or post your original design
NOTE:  We make every effort to link to original material posted by the designer. 
Please contact us if our link is not to your site!  Thanks.


Power Supplies: AC to DC Converters / Linear
#'s - A         B - K        L - S       T - Z
Power Supplies -- Main Page


Last Updated: June 02, 2021 01:44 PM

Circuits Designed by Dave Johnson, P.E. :

Display RF Signal Strength - Many cordless telephones, computer networks and cell phones use a RF transmitter lefted on the 2.45GHz band.  Using a microwave diode detector and 100uA meter, this passive circuit will display the strength this signal.  The drawing shows how a bent piece of wire can be used as the antenna. . . . Hobby Circuit designed by David Johnson P.E.-July, 2006

Energy Harvesting using a Current Transformer - Energy harvesting is all the rage these days.  With some modern electronics, information from low power sensors can be sent to a distant data collection point using a low power RF transmitter.  To power these remote sensors, various energy sources can be. . . Circuit by David A. Johnson P.E.-January, 2010

Full Wave Rectifier - This is a classic circuit that can accurately convert an AC signal to DC.  At 40KHz the input signal can be as low as 0.05 volts peak to peak.. . . Circuit by David Johnson P.E.-July, 2006

Ideal Blocking Diode Circuit for Photovoltaic Solar Panels - Most photovoltaic solar panels are used to charge a battery during the daytime.  Nearly all panels come equipped with a blocking diode.  The diode prevents DC current from flowing backwards from the battery bank into the panel at night.  The usual blocking. . . Circuit by Dave Johnson P.E.-March, 2011

Ideal Diode Function - Most photovoltaic solar panels are used to charge a battery during the daytime.  Nearly all panels come equipped with a blocking diode.  The diode prevents DC current from flowing backwards from the battery bank into the panel at night.  The usual blocking . . . Hobby Circuit designed by David A. Johnson P.E.-January, 2008

Isolated Miniature AC/DC Power Supply - This circuit uses a novel approach to produce a fully isolated and regulated 5 volts @30ma from the 120vac power line.  It uses two tiny SCRs that alternately discharge two capacitors through a miniature high frequency transformer . . . Hobby Circuit designed by David A. Johnson P.E.-June, 2000


Links to electronic circuits, electronic schematics and designs for engineers, hobbyists, students & inventors:

DC Power Supply-  Build a simple DC supply having three output terminals: regulated +5VDC, unregulated +10VDC and 7.5VAC.  The supply is suitable for microcontroller experimenting. __ Designed by Wichit Sirichote

DC to AC inverter using a 555 timer-  This DC-to-AC inverter schematic produces an AC output at line frequency and voltage.  The 555 is configured as a low-frequency oscillator, tunable over the frequency range of 50 to 60 Hz by Frequency potentiometer R4.  The 555 feeds its output ( amplified by Q1 and Q2) to the input of transformer T1, a reverse-connected filament__ Tony van Roon  VA3AVR

Digital Bench Power Supply-  PIC Project  This unit delivers 0 to 20 volts at up to 4 amps in 0.1volt increments.  The entire device runs on a PIC16F870 ( about $3 in small quantities).  This is basically a switching power supply with the voltage regulation done in software.  The PIC used here has analog inputs ( used to measure voltage and current) and hardware PWM ( pulse width modulation) output used to control the power. __ Designed by Luhan Monat-Mesa Arizona

Display RF Signal Strength-  Many cordless telephones, computer networks and cell phones use a RF transmitter lefted on the 2.45GHz band.  Using a microwave diode detector and 100uA meter, this passive circuit will display the strength this signal.  The drawing shows how a bent piece of wire can be used as the antenna. . . . Hobby Circuit designed by David Johnson P.E.-July, 2006

Dry cell battery charger-  The circuit of dry cell charger is very simple utilizing very few components.  The working of this circuit is based on PCR ( Periodic Current Reversal) principle.  Where low AC voltage is given to dry cell for charging.  A 6V-0V/1 amp secondary transformer is used for step down of AC voltage.  The time for charging is 12 to 16 hour.__

Dual 12V Power Supply-  Schematic only __ Designed by Tony van Roon  VA3AVR

Dual Polarity Power Supply-  This dual polarity power supply is easy to build, requires few parts, and is adjustable from 0-15 volts.  It is great for powering op amp circuits, as well as other circuits that require a dual supply voltage. 
 __ Contact IQ Technologies

Dual Voltage Power Supply-  The following circuit Diagram of ( DUAL VOLTAGE POWER SUPPLY) can be used for Misc..  application. It requires a few components to built.  The most important components of this circuit are REGULATORS.1 : ( AN) 7812 and 2 : ( AN) 7912 AN7812 is the Positive Voltage Regulator.  It regulates the voltage from ( almost) 24vDC to 12vDC ( accurate). __ Contact IZHAR FAREED

Dynamo Current & Voltage Regulator-  Useful for lovers of older cars, motorcycles and boats. __ Designed by Manfred Mornhinweg

Efficient LED Power Supply Has Battery Backup-  04/08/10 EDN Design Ideas:  Power three to six LEDs from an ac- or dc-power source and charge a backup battery. Design by Zhihong Yu, Juno Lighting Group, Des Plaines, IL

Emergency Power-  This unit was constructed in a plastic 4-outlet juction box ( $5 from Home Depot).  The front panel is cut from 60-thou Lexan, and a scrapped Pep-Boys battery charger provided the transformer.  The PIC16F870 keeps track of battery voltage as well as both charging and discharging currents. __ Designed by Luhan Monat-Mesa Arizona

Energy Harvesting using a Current Transformer-  Energy harvesting is all the rage these days.  With some modern electronics, information from low power sensors can be sent to a distant data collection point using a low power RF transmitter.  To power these remote sensors, various energy sources can be. . . Circuit by David A. Johnson P.E.-January, 2010

EPR-32: 25 Watt Multiple Output TOP245P Supply-  This design kit is an AC-DC power supply with universal input and 4 outputs.  The design, rated for 20 W ( 25 W peak) , is implemented using a TOP245P device from the TOPSwitch-GX IC family and an EEL25 core in a flyback topology. __

Expanded Scale Battery Volt Meter-  This circuit is used to measure the voltage on a 12V ( nominal) lead acid rechargeable battery system.  It was specifically designed for use in solar powered systems, but is general enough that it can be used for automotive or other 12V systems.  Lead acid batteries normally spend their working lifetime in the voltage range of 11-15 Volts.  This meter circuit __ Designed by G. Forrest Cook

Fast Charger for Better Lead-Acid Battery Life-  This peak limiter is simple and very effective.  Uses discrete FET gain control __

Fast Rectifier Circumvents Input-Level Effect-  12/22/94 EDN Design Ideas:  All diode-based rectifier circuits suffer from a signal-level-dependent frequency response.  This response occurs because the dynamic impedance of the diodes varies as the signal level changes.  The result is a slower frequency response and distorted rectified outputs at low signal levels compared with high levels.  An alternative approach Design by Michael Steffes and Jim Riphahn, Comlinear Corp, Ft Collins, CO

Fidelity Testing for A to D Converters-  Linear Technology AN132 __ Designed by Jim Williams - Oct 1st, 2011

Fixed Voltage Power Supply-  The fixed voltage power supply is useful in applications where an adjustable output is not required.  This supply is simple, but very flexable as the voltage it outputs is dependant only on the regulator and transformer you choose.  The maximum output current is 1.5A __ Contact IQ Technologies

Full Wave Rectifier-  This is a classic circuit that can accurately convert an AC signal to DC.  At 40KHz the input signal can be as low as 0.05 volts peak to peak.. . . Circuit by David Johnson P.E.-July, 2006

Full-Wave Rectifier Operates to 200 MHz-  07/20/95 EDN Design Ideas:  The circuit in Figure 1 uses current-feedback amplifiers to implement a wideband full-wave rectifier for applications such as a control/AGC system reference or as an amplitude indicator.  Putting the full-wave-rectifier diodes in the feedback loop of an op amp works better than does using simple diode-based rectifiers.  The op amp's loop gain Design by Rea Schmid, Comlinear Corp, Fort Collins, CO

Generate Boost Rails In a Bridge-Rectifier-  11/16/12 EDN Design Ideas:  Bridge ac inputs have the ability to sink and source current with reference to the bridge-rectifier outputs.  Many single-voltage power supplies consist of a transformer, a rectifier, and a filter capacitor, as shown in Figure 1.  This circuit is relatively inexpensive and easy to build but supplies only a single voltage.  Circuits employing op amps, data converters, and other analog circuit blocks often require additional voltages to operate.  These extra voltages can be either higher than the main supply voltage or negative. Design by Horst Koelzow, Calgary, Alberta

HF linear Amplifier with MRF454-  100W HF Linear Amp - Schematic only, no circuit description __ Designed by © 2001 - YO5OFH, Csaba Gajdos

High Current Power Supply-  Since my page was first posted, I have received a number of emails asking about a high current power supply.  I looked around, but couldn't find one that was suitable.  So, I designed this.  It is a linear supply, which might have a few of you rolling your eyes, but it takes very few parts, is simple to build and can supply huge currents. __ Contact IQ Technologies

High current regulated power supply -  Scroll to find this circuit:  The high current regulator below uses an additional winding or a separate transformer to supply power for the LM317 regulator so that the pass transistors can operate closer to saturation and improve efficiency.  For good efficiency the voltage at the collectors of the two parallel 2N3055 pass transistors should be close to the output voltage.  The LM317 requires a couple extra volts on the input side, plus the emitter/base drop of the 3055s, plus whatever is lost across the (0.1ohm) equalizing resistors (1volt at 10 amps) , so a separate transformer and rectifier/filter circuit is used that is a few volts higher than the output voltage __ Designed by Bill Bowden

High dynamic range RF Amplifier-  Schematic only, no circuit description __ Designed by © 2001 - YO5OFH, Csaba Gajdos

High Efficiency Linear & Switching Solutions for Splitting a Digital Supply-  DN172 Design Notes __ Linear Technology/Analog Devices

High Efficiency Linear Regulators-  AN32 Presents circuit techniques permitting high efficiency to be obtained with linear regulation.  Particular attention is given to the problem of maintaining high efficiency with widely varying inputs, outputs and loading.  Appendix sections review component characteristics and measurement methods. __ Linear Technology/Analog Devices

High IP3, wide band, balanced linear power Amplifier HELA-10-  AN-60-009  Application Note __ MiniCircuits.com

High side PWM Motor/Light Controller-  The diagrams are for 12V operation only and there are high side ( common ground) and low side ( common +12V) versions.  The low side version of the circuit uses an N Channel FET, the high side version of the circuit uses a P Channel FET.  N Channel devices tend to handle more current than P Channel devices, they are also less expensive.  The high side version of the circuit is useful when one side of the load has to be grounded __ Designed by G. Forrest Cook

High-Speed Rectifier Uses No Diode-  03/30/95 EDN Design Ideas:  Fig 1 shows a high-speed, full-wave rectifier-or absolute-value circuit-that uses a high-speed clamping amplifier, IC2.  This circuit is faster and performs better than rectifiers employing diodes in their amplifiers' feedback paths.  These diode-based circuits have limitations at lower signal-input levels and higher bandwidths.  These limitations Design by Paul Hendricks, Analog Devices, Wilmington, MA

Ideal Blocking Diode Circuit for Photovoltaic Solar Panels-  Most photovoltaic solar panels are used to charge a battery during the daytime.  Nearly all panels come equipped with a blocking diode.  The diode prevents DC current from flowing backwards from the battery bank into the panel at night.  The usual blocking. . . Circuit by Dave Johnson P.E.-March, 2011

Ideal Diode Function-  Most photovoltaic solar panels are used to charge a battery during the daytime.  Nearly all panels come equipped with a blocking diode.  The diode prevents DC current from flowing backwards from the battery bank into the panel at night.  The usual blocking . . . Hobby Circuit designed by David A. Johnson P.E.-January, 2008

Improved Active Rectification-  02/06/03  EDN Design Ideas:  Build an adjustable high-frequency notch filter - Rectifiers convert ac signals to dc.  You can combine a diode and a load resistor to create a half-wave rectifier, provided that the amplitude of the ac source is much larger than the Design by Reza Moghimi, Analog Devices Inc, San Jose, CA

Instrument panel lamp dimmer control-  Motorola - This circuit uses an MC3392 low side protected switch and an MC1455 timing circuit to form an automotive instrumentation panel lamp dimmer control.  The brightness of incandescent lamps can be varied by Pulse Width Modulating the input of the MC3392.  The modulating signal can be obtained directly from the MC1455 timer ( or a microprocessor).  The MC1455 is configured as a free-running clock having a frequency and duty cycle control. __ Contact IQ Technologies

Interference Free Switch Mode Pre-Regulator-  I created this circuit to fix an overheating problem with a small Chinese-made stereo set.  This simple solution to a perplexing problem worked so well that I felt the need to share it.  This circuit can be used for other applications as well. __ Designed by Andrew R. Morris

Isolated Miniature AC/DC Power Supply-  This circuit uses a novel approach to produce a fully isolated and regulated 5 volts @30ma from the 120vac power line.  It uses two tiny SCRs that alternately discharge two capacitors through a miniature high frequency transformer . . . Hobby Circuit designed by David A. Johnson P.E.-June, 2000

      <<<         This the last page of B - K


AC to DC Converters / Linear Power Supplies: 
#'s - A         B - K        L - S       T - Z


HOME Schematics Index Hobby Corner Dave's Circuits Contact Info
Imagineering Ezine Dave Johnson, P.E. Faraday Touch Switches


 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |   Link to DiscoverCircuits.com  |  Privacy Policy

Copyright  January, 1998 - June, 2021     David A. Johnson  All Rights reserved. 

 COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED!