Smart Sensitive Electronic Hearing Aid

This is the circuit diagram of electronic hearing aid featured with sensitive sound detection and energy saving, so this hearing aid will work in the long term with a 9V batery battery cycle. The common hearing aid circuits consume the battery energy continuously once they are turned on. This smart electronic hearing aid saves battery… Read More »

6V / 9V / 12V Battery Charger with Constant-Current Charging

This is the circuit diagram of battery charger which has many important features such as current-constant charging, overcharge protection, short-circuit protection, deep discharge protection and more. The constant-current charging is a popular method for lead-acid and Ni-Cd batteries. In this circuit, the battery is charged with a constant current that is generally one-tenth (1/10) of… Read More »

5V DC Regulated Power Supply with Short Circuit Protection

This is the circuit diagram of 5V DC regulated power supply which featured with short circuit protection system. There are 2 kind of output that are regulated 5V DC with short circuit protection and without circuit protection. The main circuit is protected from any damage due to short-circuit in the additional power supply circuit by… Read More »

Water Level Indicator with Single 7 Segment LED Display

This is an unique water level indicator circuit which use 7 segment LED display to show the current water level in the water tank. Most water level indicator circuits for water tanks are based upon the number of LEDs that glow to indicate the current level of water in the water tank / container. This… Read More »

Electronic Dice Based Microcontroller Atmel AT89C2051

This is the circuit diagram of electronic dice which built based microcontroller chip of Atmel AT89C2051. The application of this electronic dice is similar to the one used in a game of dice. The circuit generates the random numbers which not displayed numerically, but represented by the number of glowing LEDs. The LEDs are the… Read More »

Car Anti-Theft Protection with Buzzer

This is the circuit diagram of car anti-theft to protect and increase the security of your car, prevent your from stealing. This circuit is very simple, low cost and easy to built. When key-operated switch S2 of the car is turned on, 12V DC supply from the car battery is extended to the entire circuit… Read More »

Battery Charger + Small LED Lamp based Solar Cell / Photovoltaic

This is the circuit diagram of rechargable battery charger which use solar cell / photovoltaic as the DC source. This circuit works to charge 3 types of rechargable batteries that are lead acid, Ni-Cd and Li-ion. The lead-acid batteries are generally utilized in emergency lamps and UPS. The photovoltaic module or solar cell explained in… Read More »

Electronic Candle Circuit using TTL IC

This is a simple and easy built electronic candle circuit which build using TTL (transistor-transistor logic) that are 74LS164, 74LS86 and 74LS00. This circuit will give the effect of candle light in a normal 220V electric bulb lamp. A candle light, as we all know, resembles a randomly glimmering light. So, the objective of this project… Read More »

Electronic Stopwatch

The above simple circuit design can be utilized as an accurate stopwatch to count up to 100 seconds with a determination of 0.01 second or up to 1000 seconds with a determination of 0.1 second. This stop-watch might be utilized for sports, games and other comparable different exercises.