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What is digital optocoupler?
An Optocoupler, is an electronic components that interconnects two separate electrical circuits by means of a light sensitive optical interface. Both the LED and photo-sensitive device are enclosed in a light-tight body or package with metal legs for the electrical connections as shown.
What are digital isolators used for?
Digital isolators are integrated devices used to isolate digital signals and transfer digital communication across an isolation barrier.
What’s the difference between an optocoupler and an optoisolator?
The distinguishing feature between these two terms is the amount of voltage being isolated. An optocoupler is used to transmit either analog or digital information from one voltage potential to another while maintaining isolation of the potentials of less than 5,000 V.
How is an optocoupler similar to a CMOS digital isolator?
The basic operating principle of the CMOS digital isolator is somewhat analogous to that of an optocoupler, with the exception that output logic state control is determined by the presence or absence of a high-frequency (HF) carrier instead of light. Figure 2B shows the die configuration and bonding of a 150 Mbps, six-channel CMOS digital isolator.
How does an optocoupler work in a transistor?
Referring to Figure 1A, most optocouplers are composed of a light-emitting diode (LED), photo detector and output driver (usually a transistor or buffer). Current flowing though the LED causes emitted light to strike the photo detector, creating a current flow from VDD to the base of the output device, driving the output low.
What is the propagation delay of an optocoupler?
A consideration facing designers is the speed of transmitting the digital data while minimizing the propagation delay. Most optoisolators/optocouplers are used for data rates below 10 Mbits/s, and the propagation delay may be in the 2 to 20-µs range.