This voltage monitor circuit is based on an Elektor design with a 555 timer IC in the book 302 Circuits, which uses two LEDs (red and green) to indicate whether the voltage is within range (... Read more
The author wanted a very cheap and simple alarm for some of his possessions, such as his electrically assisted bicycle. This alarm is based on a cheap window alarm, which has a time-switch a... Read more
This circuit is a simple but high-quality preamplifier using a DS1882 digital potentiometer, a device specially designed for audio applications. The potentiometer is controlled over an I2C i... Read more
The RS Latch in the 555 Timer can be used with the Reset and Trigger inputs. The output is set or reset with the momentary inputs applied at these inputs. As the S and R inputs are controlle... Read more
Schematic Diagram: Here we are going to make a flip-flop based 4 bit counter. ie it counts 0000-1111 in a binary system. The clock of the first flip-flop is either natural crystal clock or... Read more
The timer is based on the well-known display driver LM 3915, which has a logarithmic scale. This may be seen strange, but is not because a simple RC network is used for time measurements. T... Read more
Timer chip 1CM7250 from Maxim enables a very simple timer to be designed. The IC has eight programmable inputs for connecting to say two thumbwheel switches. Units are set in BCD code on the... Read more
This compact four-digit digital counter is suitable for any application, such as clocks, frequency meters, digital voltmeter, tachometers, stop-watches, scoreboards, etc. The counter module... Read more
There is a digital version of the 200 well-known Type 555 timer IC: the HCT5555. The traditional 555 can astable or monostable, within, be used a the timing determined by an RC network. Crys... Read more
Many young children will insist on keeping the bedside light on for a couple of minutes after the storybook has been closed and father or mother has gone downstairs. They are also prone to f... Read more
