Current transfer ratio is comparable to BJT’s HFE or beta (β). This is the ratio of the optocoupler’s collector current to the forward current. Current transfer ratio is popular by its abbreviation CTR. CTR is simply the measure of the optocoupler’s transfer efficiency. If we recall the basics, optocoupler is a semiconductor device with a light source and a detector.
READ
Way back several years ago, power supply designers and engineers are continuously searching for innovation. Long time ago what is available is only the linear type power supply. A linear power supply will consume a lot of power in order to provide regulation. This huge power consumption sacrifices the efficiency of the power supply. Try to imagine if you are
READRelay is made up of two elements; the coil and the contact. The coil needs to be energized so that the contact will change state. For detailed analysis on how to drive the relay coil for it to energize read this. In this topic we will jump directly to relay kickback voltage analysis. As mentioned, relay has a coil. This coil
READ
Opto coupler CTR explanation is not well elaborated by other authors and before I was also having hard time of understanding what is it. Current transfer ratio or commonly known as CTR is the ratio of the collector current to the forward current of an optocoupler. It is synonymous to a current gain of a bipolar junction transistor. If this is the first
READMOSFET is not well discussed in the undergrads; much more how to designing MOSFET switch. MOSFET stands for metal oxide semiconductor field effect transistor. Actually it is easier than BJT if we are talking a switch circuit. Nowadays MOSFET is very popular in circuit designs. Such in automotive, power supply and general electronics as a low side and high side
READ
One of the usual applications of optocoupler is to provide isolation between two ground reference. That is why it is often seen in power supply feedback circuit. How to analyze optocoupler in feedback system is to discussed in this article. Keep on reading below. How to analyze optocoupler in feedback system is not as difficult as you think. However, the lack
READ
How to drive a transistor into hard saturation? In using a transistor to operate as a switch you must drive it into saturation. Saturation happens when the collector current cannot further increase despite there is base current increase. The saturation level of every transistor varies. The usual range is from 0.7V to ideally zero. For instance for a BC817-25 transistor,
READ
BJT operation modes are at cut-off, saturation and active or linear. At cut-off, simply the BJT is not operating, say the base-emitter voltage requirement is not meet. The corresponding collector-emitter voltage is the same with the collector supply. At saturation the other hand, the BJT is driven into the point wherein its collector current can no longer increase despite of the increase
READ