## What is Source and Sink Current

What is source and sink current? Source and sink currents are used by integrated circuits such as microcontrollers, digital signal controllers, digital signal processor and any application specific integrated circuits. Sometimes these are being interchanged by others that it should not be. In this article we will know the answer of the question what is source and sink current. Source

## MOSFET Power Dissipation and Junction Temperature Calculation

There are some factors to consider in calculating MOSFET power dissipation. When the power dissipation is known, it is possible to compute the junction temperature of the MOSFET. Important to take that a MOSFET installed with no heatsink has different computation strategy compared to the one with a heatsink. Small current or low power MOSFETs are usually mounted to PCB

## Optocoupler Circuit Design and Detailed Analysis

Actually, Optocoupler circuit design is not that difficult as some thought. It’s just like you are designing a BJT circuit. If a BJT has its beta or current gain, optocoupler has its CTR or current transfer ratio. Once you know what a CTR is and learn how to use it, then Optocoupler circuit design is that easy. Current transfer ratio

## Open Collector and Push-Pull Configurations

Open collector and push-pull configurations are IC pin driving techniques (particularly output pin). Nowadays ICs such as microcontrollers, digital signal controllers and processors are already configurable. The programmer can set the output pin to either open collector or push-pull implementations. Open collector is an implementation wherein the IC will not provide the supply by itself the external circuit by floating its

## Factors Affecting Current Transfer Ratio of Optocoupler

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.

## How to Calculate MOSFET Power Dissipation

MOSFET power dissipation is the sum of the conduction loss and the switching losses. These power losses are very different from each other. Conduction loss is the static loss wherein the main contributor is the drain to source on-state resistance of the MOSFET as well as the drain current. While switching losses are dynamic losses that are dependent on the

## How to Select a MOSFET for Power Electronics

These are the important things to consider on how to select a MOSFET for power electronics. These parameters when considered during the development stage, you can ensure a product with a very high reliability. 17 Key Items to Consider on How to Select a MOSFET for Power Electronics 1. Gate to Source Threshold Voltage (VGSth) Let us start this tutorial

## How to Drive a Relay with a MOSFET

It is very common application to drive a relay with a MOSFET. From household applications to automotive are using this circuit. There are some aspects to consider like the stress on the MOSFET, the level of driving voltage to guarantee MOSFET saturation, the level of the actual voltage applied to the relay coil if enough to meet the requirement and