What is the function of PC817?

PC817 is normally used in embedded project for isolation purposes. In my embedded projects, I place PC817 after Microcontroller Pins to isolate back EMF, in case of motor control etc. PC-817 has several applications e.g. noise suppression in switching circuits, input/output isolation for MCU (Micro Controller Unit).

What does a photocoupler do?

An opto-isolator (also called an optocoupler, photocoupler, or optical isolator) is an electronic component that transfers electrical signals between two isolated circuits by using light. Opto-isolators prevent high voltages from affecting the system receiving the signal.

What is forward current in optocoupler?

Light-Emitting Diode (LED): Forward Current: IF (mA) The allowable maximum current at which destruction does not occur, within the allowable power dissipation (PD) range of the LED on the light-emitting side when the ambient temperature is 25 °C.

What is CTR optocoupler?

The current transfer ratio is a parameter similar to the DC current amplification ratio of a transistor (hFE) and is expressed as a percentage indicating the ratio of the output current (IC) to the input current (IF). CTR(%) = (IC/IF) x 100.

Where can I use optocoupler?

Optocouplers can either be used on their own as a switching device, or used with other electronic devices to provide isolation between low and high voltage circuits. You’ll typically find these devices being used for: Microprocessor input/output switching. DC and AC power control.

What is PC817?

PC817 is an optoisolator consists of an infrared diode and phototransistor. In electric circuits, we use mostly filters to remove noise. The circuit based on the capacitor and resistor always removes the noise from the incoming signal but the value capacitor and resistor always depend on the incoming signal.

What is optocoupler and how does it work?

An optocoupler (also called optoisolator) is a semiconductor device that allows an electrical signal to be transmitted between two isolated circuits. Two parts are used in an optocoupler: an LED that emits infrared light and a photosensitive device that detects light from the LED.

What is the difference between photocoupler and optocoupler?

Characteristic Differences Although photocouplers conduct only DC (direct current) in the output, OCMOS FETs can conduct both DC and AC (alternating current) in the FETs. Generally, the operating speed of photocouplers is in microseconds or more rapid, while that of OCMOS FETs is as slow as milliseconds.

Do optocouplers need resistors?

There are many different applications for optocoupler circuits, so there are many different design requirements, but a basic design for an optocoupler providing isolation for example between two circuits, simply involves the choice of appropriate resistor values for the two resistors R1 and R2 shown in Fig. 5.2. 1.