Do More

 Make it a practice to turn off the lights in your room - Tips To Save Energy Lots of people today leave their bedrooms without turning the lights off. Although lights do not consume much electricity, lots of energy would be wasted if you constantly left them turned on for the most parts of the day, even if you are not inside the room. Thus, make it a practice to turn off the lights, so that you can save energy.  Make it a practice to turn off the lights in your room - Tips To Save Energy

View on Scribd View in Google Docs Download PDF (4shared)

This is a Variable 5 to 20V DC Supply Circuit Diagram . If you are looking for a low drop voltage regulator that can provide a power supply of 1A with an output voltage of between 5V and 20V DC, National Semiconductor LM2941 Low Dropout Adjustable Regulator is that you can pick to make use of. It's a typical dropout voltage of 0.5V which means that the input supply need only must be 0.5V DC over the desired output voltage.  Variable 5 to 20V DC Supply Circuit Diagram   Its other features include internal short circuit current limit and reverse battery protection. As shown in the schematic below, the regulator has five pins which consists of the ON/OFF control, Input Voltage, Output Voltage, Ground & Adjustable pins. ON/OFF is used for the purpose of switching on & off of the regulator. The capacitors C1 & E1 are to be placed as close as feasible to the regulator.  The output of the circuit can be varied by varying the worth of potentiometer VR1 from 5V DC to 2...

Ever needed a low power 120volt AC  power source for your car, van or truck? Well this circuit should do the trick for you. It will supply 15 watts of AC power to a device. It should power lamps, shavers, small stereos and small appliances. If you draw to much power the circuit will shut down all by itself. 12 Volt DC to 120 Volt AC Inverter Circuit Diagram The output of this circuit is a square wave so there may be some noticeable hum on audio units plugged into it. To reduce some of the hum increase the value of the output capacitor which is at .47uf now. That transistor in the circuit are high power PNP transistors. Radio Shack part number 276-2025 are good ones to use or TIP32. The transformer is a 24 volt 2 amp center tapped secondary Radio Shack part number 273-1512 or equivalent.

Kit that can change the normal 12v dc voltage from a car battery, battery bike 12V motor. With the current 7A. so this circuit is very suitable for power car amplifiers and sound systems that use simple 12V battery. Kit converter is also equipped with inputs "SEND" to activate the circuit and also send this interchangeable inputs is connected to the Tape / cd / dvd player of your car. And input "send" is if the non-connected with an output of "send" player car you then connect it to +12 hrs on v from the battery / batteries The series is already in the test kit and has been functioning normally.

RESISTOR TO REDUCE L200 POWER DISSIPATION ELECTRONIC DIAGRAM Instead of in series with the input, the resistor R can be connected between pins 1 and 2 of the IC if the load is constant. You can see this in the right figure. This will make some part of the load current flows through the resistor and the other part through the device.

This is a Simple 1.5V Battery to 5V Voltage Converter Circuit Diagram. Stable and secure 5V DC (at 200mA max) from an ordinary 1.5V AA sized cell. At the heart of this circuit is IC1 MAX756 from Maxim, which is a CMOS step-up DC-DC switching regulator for small, low input voltage or battery-powered systems. Simple 1.5V Battery to 5V Voltage Converter Circuit Diagram MAX756 accepts a positive input voltage down to 0.7V and converts it to a higher pin selectable output voltage of 5V (or 3.3V). Typical full-load efficiency for the this IC is greater than 87%. Max756 combine a switch-mode regulator with an N-channel MOSFET, precision voltage reference, and power-fail detector in a single monolithic device. The MOSFET is a “sense-FET” type for best efficiency, and has a very low gate threshold voltage to ensure start-up under low-battery voltage conditions (1.1V typ). The circuit can be easily wired on a very small rectangular common PCB.All connections should be kept as short as possible. ...

I have a circuit where I want to have a constant current of 2mA through a variable resistor. I've been told that I could probably use a LM317 as a current regulator, with one resistor on the ouput. But I've read some places that the LM317 takes minimum 5-10mA load to function correctly. How can I achieve a constant current output of 2mA when I don't know the resistance of the variable resistor? The input voltage is about 2.755V. Output voltage doesn't matter, just the current. Here's an image to my feeble attempt at a schematic: The LM317 with the single series resistor between output and adjust input is actually a fixed current source, not a current limiter. You don't need the LM317 to create a current limiter, a few discrete components will do: For a limiting at 2mA you select a 330 Ω resistor for R S E N S E . If there flows 2mA through it Q2 will start to conduct and reduce the base voltage of Q1, so that its current is cut off. edit (re changed question) ...

A simple electric motor homemade, easy to make. 1. 1 meter of wire 2. magnet 3. one battery AA or AAA 4. Improvisation

This is the project of simple Period To Voltage Converter Circuit Diagram . The input signal drives ICD. Because ICD`s positive input (V+) is slightly offset to + 0.1 V, its steady state output will be around +13 V. This voltage is sent to ICC through D2, setting ICC`s output to +13 V. Therefore, point D is cut off by Dl, and CI is charged by the current source.  Assuming the initial voltage on CI is zero, the maximum voltage (^Cinax) is given by: When the input goes from low to high, a narrow positive pulse is generated at point A. This pulse becomes -13 V at point B, which cuts off D2. ICC`s V+ voltage becomes zero.  Period To Voltage Converter Circuit Diagram The charge on CI will be absorbed by ICC on in a short time. The time constant of C2 and R5 determines the discharge period— about 10 /is. ICB is a buffer whose gain is equal to (R& + R9)~Rg = lM5. ICD`s average voltage will be (1362f 1.545) + 2 = 1052/. RIO and C3 smooth the sawtooth waveform to a dc output.

The creator built a neat looking project which uses a piezoelectric element from a tweeter to detect vibrations. He is using a Zilog eZ8 series microcontroller which seemed to be very popular years ago. This project dependently using a strong vibration while the enclosure has been placed on the top of vibration sensor. The LED matrix has two eyes the wandering around effects. Whenever there is no vibration being detected the eyes will shut down as if they were sleeping. A button was placed behind to manually switch it into various modes. It uses a four AA batteries and can draw 150uA when asleep while it draws for about 150mA when up.

This is a 5V to 12V DC-DC step-up (boost) converter circuitry that is especially ideal for the USB powered applications. First of all a USB port has two current supply modes. Before detecting the connected device, it supplies maximum 100mA to the load. After recognizing the device, it increases the output current up to 500mA. In this circuit, controller (LT1618) also provides two input current modes. 100mA and 500mA input modes can be selected by the user. Output currents are limited due to the increased potential difference at the output. When the demand of the load increases, output voltage will start to decrease. For example, if the circuit operates in the 100 mA input mode, when the load is 35 mA, the output voltage will be kept at 12V. But if the load increases to 50 mA,output voltage will reduce to 8V to maintain the constant 100 mA input current.

The creator built a neat looking project which uses a piezoelectric element from a tweeter to detect vibrations. He is using a Zilog eZ8 series microcontroller which seemed to be very popular years ago. This project dependently using a strong vibration while the enclosure has been placed on the top of vibration sensor. The LED matrix has two eyes the wandering around effects. Whenever there is no vibration being detected the eyes will shut down as if they were sleeping. A button was placed behind to manually switch it into various modes. It uses a four AA batteries and can draw 150uA when asleep while it draws for about 150mA when up.

Raj from Embedded Lab shows in his latest tutorial guide how to implement adaptive brightness control to seven segment LED displays for optimum readability in all illumination conditions. The technique has been demonstrated by constructing a temperature and humidity meter that adapts the brightness of the seven segment LED displays to the surrounding lighting conditions.The project uses a general purpose LDR to sense the surrounding illumination and MAX7219 to drive the LED display.

Normally analogue-to-digital converter (ADC) needs interfacing through a microprocessor to convert analogue data into digital format. This requires hardware and necessary software, resulting in increased complexity and hence the total cost. The circuit of A-to-D converter shown here is configured around ADC 0808, avoiding the use of a microprocessor. The ADC 0808 is an 8-bit A-to-D converter, having data lines D0-D7. It works on the principle of successive approximation. It has a total of eight analogue input channels, out of which any one can be selected using address lines A, B and C. Here, in this case, input channel IN0 is selected by grounding A, B and C address lines. Usually the control signals EOC (end of conversion), SC (start conversion), ALE (address latch enable) and OE (output enable) are interfaced by means of a microprocessor. However, the circuit shown here is built to operate in its continuous mode without using any microprocessor. Therefore the input control signals...

This little circuit uses a LM317 variable voltage regulator to adjust the input voltage down to +9 volt, or whatever else you need. Just a solid basic circuit without bells and whistles. You can do with a 10uF capacitor for C1 if your battery is close to this circuit. If it is located more than 3 feet increase the value to 100uF or above. Without a coolrib it can easily handle 500mA. If you need more, or the maximum current (1.5A), then a good coolrib is required. Trimmer potent meter R3 will vary the output voltage. Ceramic capacitor C2 improves frequency/transient response. Can be omitted if not needed for your application. If you want extra protection in case the adjust pin is short circuited, add an extra 1N4001 diode over the input and the output. Cathode to input. But normally only used if the output is way over 25V. R1 and R3 determine the output voltage. You can adapt them for your own needs and applications. Use the following formula: (((R1+R3)/R2)+1)*1.25=V-out which...

Amplification is the method of increasing the amplitude of a AC signal current or voltage such as audio signal for sound or video signal for a television picture. The amplifier allows a small input signal to control a bigger amount of power in the output circuit. The output signal is a replica of the original input signal but has higher amplitude. Amplification is necessary as in most applications, the signal is weak to be used directly. For example, an audio output of 1mV from a microphone is unable to drive a loud speaker which requires a few volts to operate. Hence, the signal require to be amplified to a few volts before it can be fed in to the loud speaker. NP N Transistor Circuit Configurations An example of different type of transistor configurations in the circuit is as shown in Figure one below. (1) The common emitter(CE) circuit makes use of emitter as its common electrode. The input signal is applied to the base and the amplified output is taken from the collector. This is t...