Free Simple Circuit Diagram
This relay circuit is controlled by almost any type of infrared remote controller. This circuit works on assumption that almost all remote controller use high frequency modulated infrared light. By filtering out un-modulated or low frequency modulated signal, this circuit will be able to remove any interference from ambient infrared light coming from other sources such as sun light, soldering […]
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This solid state relay (SSR) equivalent circuit is made of optocoupler and a triac. This SSR circuit is also designed with LED protection from overvoltage and reverse polarity. The diode 1N4002 is the reverse polarity protector, as it will short the wrong polarity to null the voltage with the help of 150 Ohm series resistor. The 2N4403 transistor will protect […]
Read moreLM111 comparator can be used o design a relay driver with TTL strobe, this can be used to provide more control of your relay driver. You can control the strobe input using a microcontroller or other digital signal. Here is the schematic diagram of the relay driver: [Source: National Semiconductor Application Note]
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This is a Driving Relay circuit using 555 IC. The circuit is used to drive a relay to avoid 555 hangs up, it uses an inductive feedback. The coil is prevented to drive Pin 3 below a negative 0.6V by a clamp diode that across the coil. However, in some case, this negative voltage maybe cause the timer to malfunction. […]
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