TRIAC Electronic Circuits

TRIAC Circuits
Last Updated on: Sunday, April 15, 2012 07:44 AM

Circuits Designed by Dave Johnson, P.E. :

AIR TRANSPARENCY MONITOR, XENON FLASH RECEIVER
This is Page 2 of the air transparency monitor receiver circuit.

CIRCUIT FORMS DIVIDE BY 1.5 COUNTER
Two inexpensive ICs divide a TTL clock signal by 1.5. By following the circuit with another flip/flop, you could also generate a divide by three function.

HONEYBEE COUNTER
I designed a circuit similar to this one a long time ago to help a beekeeper count the number of bees going into or out of a hive. The low power circuit uses a slotted opto-sensor to detect the passing bees. The circuit advances an electronic counting module whenever a honeybee passes through the sensor. The device only counts the number of bees going through the sensor. A different circuit would be needed to count the number of bees only going out or only coming into the hive.

SOLID STATE RELAY REQUIRES ONLY 50uA DRIVE CURRENT
This circuit demands a control current that is 100 times smaller than that needed by a typical optically isolated solid state relays. It is ideal for battery-powered systems. Using a combination of a high current TRIAC and a very sensitive low current SCR, the circuit can control about 600 watts of power to load while providing full isolation and transient protection.

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

AC Switching with TRIAC From TTL - The MC3032 is an optoisolator TRIAC driver. The 180-ohm resistor sets the current for the LED emitter in the optoisolator. Change the value of this resistor, if necessary, to get reasonable current ASCII format (e.g., 15 mA). Note that you cannot test this circuit without a load. The TRIAC will not switch unless connected to an AC voltage source, so you can't test it for simple switching w/o applying AC and a load. Note the 500V ating on the .01 cap. (ASCII format circuit added 4/02)

All Digital Circuit Fires TRIAC - 07/21/94 EDN-Design IdeasThis digital circuit allows a µP to control ac power precisely without using any digital-to-analog circuitry.… [Design Idea by Robert Trescott Jr, GTE ImagiTrek, Carlsbad, CA]

AN958: Low-Cost Electric Range Control using a TRIAC - Microchip Application Note Published 14-Oct-04 (app note added 2/06)

Circuit forms Divide by 1.5 Counter - Two inexpensive ICs divide a TTL clock signal by 1.5. By following the circuit with another flip/flop, you could also generate a divide by three function.... [Designed by David A. Johnson]

CMOS Gate Implements Reverse Phase Control - 05/21/98 EDN-Design Ideas....The circuit in Figure 1 implements a "reverse" phase control, using only a single CMOS 4001 quad NOR gate. The circuit is known as a reverse phase control because, unlike with common triac or SCR controls, conduction begins at the zero crossing of the ac sine wave. Timing of the turn-off point....File has seeveral circuits, scroll down.... [Design Idea by JC Johnson, Lithonia Lighting, Decatur, GA]

Honeybee Counter - I designed a circuit similar to this one a long time ago to help a beekeeper count the number of bees going into or out of a hive. The low power circuit uses a slotted opto-sensor to detect the passing bees. The circuit advances an electronic counting module whenever a honeybee passes through the sensor. The device only counts the number of bees going through the sensor. A different circuit would be needed to count the number of bees only going out or only coming into the hive.... [Designed by David A. Johnson]

Low-Cost Electric Range Control using a TRIAC - Microchip Application Note Published 14-Oct-04 (app note added 2/06)

Solid State Relay Requires only 50uA Drive Current - This circuit demands a control current that is 100 times smaller than that needed by a typical optically isolated solid state relays. It is ideal for battery-powered systems. Using a combination of a high current TRIAC and a very sensitive low current SCR, the circuit can control about 600 watts of power to load while providing full isolation and transient protection. Published in Electronic Design, Dec 2, 1996. …. [Designed by David A. Johnson]

TRIAC Light Controller - This project is intended for controlling mains powered disco lighting, although there are many other possible uses for controlling almost any mains appliance. It will control five seperate channels at up to 3 Amp per channel. This could be increased by designing another PCB with wider tracks than the PCB included with this design.... [Matthew Hewson's circuit]

TRIAC Light Dimmer - Schematic conly, no circuit description

TRIAC Light Dimmer - This little circuit can be used to dim lights up to about350-Watts. It uses a simple, standard TRIAC circuit that, in my experience, generates very little heat. Please note that this circuit cannot be used with fluorescent lights. (added 4/02)

Triac lighting and heating controller uses few parts

- 2-Sep-04 Issue of EDN The triac lighting-control circuit in Figure 1 is small and inexpensive because load and housekeeping power come directly from the line voltage, thereby eliminating bulky, expensive supplies. The CLZD010 closed-loop controller maintains constant light intensity by automatically adjusting the timing of the triac's firing until the feedback signal and setpoint command are equal.... [Design Idea by David Caldwell, Flextek Electronics, Carlsbad, CA]

Triac Test - These two testing procedures are for use with a digital multimeter in the Ohm's test-range. Testing procedure was actually designed for testing inside micro-waves (magnetrons), but should be no difference in any other circuit. Test inor out circuit….. [Tony van Roon's circuit]

TRIAC Circuits