Contents
What does a resistor block do?
A resistor is an electronic component that reduces or restricts the flow of electrons or electric current to certain level. How much electric current does a resistor blocks is depends on the resistance of a resistor. Hence, they cannot control the flow of electrons or electric current through them.
Which of the following is true about optocouplers?
Optocoupler can be used in both input. and output circuitry. Optocoupler acts as an input device. Optocoupler acts as an output device.
Do Resistors reduce voltage?
If a component in your circuit requires less voltage than the rest of your circuit, a resistor will create a voltage drop to ensure the component does not receive too much voltage. The resistor will create a voltage drop by slowing down, or resisting, the electrons as they try to flow through the resistor.
What is optocoupler in embedded system?
An optocoupler (or an optoelectronic coupler) is basically an interface between two circuits which operate at (usually) different voltage levels. The key advantage of an optocoupler is the electrical isolation between the input and output circuits.
What kind of resistor is used in optocoupler?
The 68R resistor is used to Control the BT136 TRIAC which is controlled by the photo-TRIAC inside the opto-coupler unit. This type of configuration is used to control electrical appliances using low voltage circuitry. The IL420 is used in the upper schematic which is a photo-TRIAC based Opto-coupler.
Why do we need optocouplers in our electronics?
Optocouplers not only protect sensitive circuits but enable an engineer to design a variety of hardware applications. Optocouplers can avoid a great deal of cost in replacing components by protecting them. However, optocouplers are more sophisticated than fuses.
Why does an optocoupler have a high saturation voltage?
You could also place the transistor on the high side with a resistor between emitter and output ground, so when the input goes high the output at the emitter is high too. But beware, most common optos have a high saturation voltage because of the limited base drive, sometimes in the order of 1 Volt!
What kind of RX unit does an optocoupler use?
Most modern optocoupler devices use a phototransistor as their Rx unit; such a device is known simply as an ‘optocoupler,’ since the input (the LED) and the output (the phototransistor) devices are optically coupled. Figure 2 shows the basic form of an optocoupler, together with a very simple application circuit.