## Kirchhoffs Circuit Law

We saw in the Resistors tutorial that a single equivalent resistance, ( RT ) can be found when two or more resistors are connected together in either series, parallel or combinations of both, and that these circuits obey Ohm’s Law. However, sometimes in complex circuits such as bridge or T networks, we…

## Real-Time Clocks

This information can be read by a microprocessor, usually over a serial interface to facilitate the software performing functions that are time dependent. RTCs are designed for ultra-low power consumption as they usually continue running when the main system is powered down. This enables them to maintain current time against…

## Electrical Units of Measure

The standard units of electrical measurement used for the expression of voltage, current and resistance are the Volt [ V ], Ampere [ A ] and Ohm [ Ω ] respectively. These electrical units of measurement are based on the International (metric) System, also known as the SI System with other commonly used electrical units being derived from SI base units. Sometimes…

## DC Circuit Theory

All materials are made up from atoms, and all atoms consist of protons, neutrons and electrons. Protons, have a positive electrical charge. Neutrons have no electrical charge (that is they are Neutral), while Electrons have a negative electrical charge. Atoms are bound together by powerful forces of attraction existing between…

## 7-segment Display Counter

Nowadays it is very easy to display numbers and letters across multiple LED displays using micro-controllers, such as the Arduino or Raspberry-Pi, along with a small bit of software related code to display the required digits. But sometimes as an Electronics student or hobbyist we want to display two or…

## AC/DC Converters

Circuits often require an integrated AC power source as the optimum strategy to reduce size, cost or due to application specific needs. Understanding the key concepts associated with conversion and the practical alternatives available is a good start towards a successful design. Safety First! When the AC source is a…

## MOD Counters

The job of a counter is to count by advancing the contents of the counter by one count with each clock pulse. Counters which advance their sequence of numbers or states when activated by a clock input are said to operate in a “count-up” mode. Likewise, counters which decrease their…

## Bidirectional Counters

As well as counting “up” from zero and increasing or incrementing to some preset value, it is sometimes necessary to count “down” from a predetermined value to zero allowing us to produce an output that activates when the zero count or some other pre-set value is reached. This type of…

## BCD Counter Circuit

We saw previously that toggle T-type flip flops can be used as individual divide-by-two counters. If we connect together several toggle flip-flops in a series chain we can produce a digital counter which stores or display the number of times a particular count sequence has occurred. Clocked T-type flip-flops act…

## Simple LED Flasher

The electronics student or hobbyist’s always likes to make various circuits for their home or school and especially ones that flashes a few lights, and there are many circuits and kits on the market that can flash any number of LED’s or lights periodically, randomly or sequentially but one very…

## Synchronous Counter

In the previous Asynchronous binary counter tutorial, we saw that the output of one counter stage is connected directly to the clock input of the next counter stage and so on along the chain. The result of this is that the Asynchronous counter suffers from what is known as “Propagation…

## Frequency Division

In the Sequential Logic tutorials we saw how D-type Flip-Flop´s work and how they can be connected together to form a Data Latch. Another useful feature of the D-type Flip-Flop is as a binary divider, for Frequency Division or as a “divide-by-2” counter. Here the inverted output terminal Q (NOT-Q) is connected directly back…