Category: Digital Electronics Projects

The circuit 1/86400 Hz frequency generator provides one clock pulse every 24 hours from a 1 Hz input clock pulse source, which is commonly available through a digital clock. It can be used to provide am/pm indication in those digital clocks which do not have this facility, or it may be utilized to advance the date of an electronic calendar every day. It can also be used to trigger an alarm at a determined time without fail. Circuit Description of 1/86400 Hz Frequency Generator The present circuit 1/86400 Hz frequency…

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Wireless control of devices using infrared is not new to electronics hobbyists. Now, here is wireless control of the device using ultrasonic sound waves tested in BEP Lab. The project ultrasonic Lamp brightness controller circuit uses ultrasonic sound waves (above 20 kHz) for remote control of lamp brightness. Circuit Description of Ultrasonic Lamp Brightness Controller Circuit As with all wireless control systems, the Ultrasonic lamp-brightness controller comprises a transmitter and receiver circuit. Transmitter Circuit | Ultrasonic Lamp Brightness Controller Circuit The transmitter circuit generates an ultrasonic sound wave of about 40-50…

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The circuit described here is a hex to binary converter circuit using four, 8-input NAND gate 7430 ICs. The input keyboard switches SW1 to SW15 are connected in such a manner that the pressing of any switch produces the binary ABCD outputs of the corresponding decoded numbers. When all inputs in a NAND gate are high, it produces a low output, But when any of its input goes low, its output becomes high. Normally, all switches are open, the binary output is 0000. Pressing a switch gives a ‘low input’…

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ICs 555 and 4017 are well-known to electronics hobbyists. Presented here is a very interesting project of an LED stopwatch Circuit using timer 555 and decade counter 4017 ICs. This stopwatch is able to monitor time from one second to 60 minutes. It can be used in sports, laboratories, etc. IC 555 (IC1) is the heart of the circuit. It is used in astable multivibrator mode. The special feature of this mode is that if this pin 4 of IC1  is kept at a high logic, it produces a clock…

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The flash type converter is the simplest and the fastest type of analog to digital converter. The entire digital output word is present just after the propagation delay time of comparators and the encoding logic gates. A typical conversion time of a three-bit flash analog to a digital converter is 33 ns. The circuit of a three-bit flash analog to digital converter shown in figure 1, needs just three comparators and no combinational logic circuitry. Circuit Description of Three Bit Flash Analog to Digital Converter In this circuit, the reference…

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