ffd

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 poss...

This circuit using a dual-timer NE556 can produce 1Hz pulses spaced 5 seconds apart, either manually or automatically. IC NE556 comprises two independent NE555 timers in a single package. It is used to produce two separate pulses of different pulse widths, where one pulse initiates the activation of the second pulse. The first half of the NE556 is wired for 5-second pulse output. When slide switch S2 is in position ‘a’, the first timer is set for manual operation, i.e. by pressing switch S1 momentarily you can generate a single pulse of 5-second duration. When switch S2 is kept in ‘b’ position, i.e. pins 6 and 2 are shorted, timer 1 in NE556 triggers by itself. The output of the first timer is connected to trigger pin 8 of second timer, which, in turn, is connected to a potential divider comprising resistors R4 and R5. Resistor R1, preset VR1, resistor R2, preset VR2, and capacitors C2 and C5 are the components determining time period. Presets VR1 and VR2 permit trimming of the 5-secon...

This 1.5 volt led fasher runs more than a year on a single 'd" cell and alternately flashes 2 LEDs at about a 1 second rate. The circuit employs a 74HC14 CMOS hex inverter that will operate at very low voltages (less than 1 volt). One section is used as a squarewave oscillator (pins 1 and 2), while the others are wired to produce a short 10mS pulse on alternate edges of the square wave so the LEDs will alternate back and forth. The output sections each use a capacitor charge pump to increase the voltage for the LEDs.  The circuit draws an average current of 800uA from the 'D' battery and the LED peak current is about 40mA with a fresh battery and drops to about 10mA as the battery voltage falls to 1.1 volts. The capacity of a alkaline 'D' cell is about 12 amp hours with a cutoff voltage of 1.1 so the circuit should run about 12/.0008 = 15000 hours or maybe 625 days, but I haven't verified that yet. The idea for this circuit came from a single 1.5 volt LED f...

Have you ever wondered exactly what is going on in the 2.4GHz WiFi and ISM band around your house. What channel is it best to set your wireless router to? Why are you getting such poor performance across your WiFi network? Is your neighbour on the same frequency? Just what is out there? This neat little gadget will sniff the airwaves and give you a graph of the signal strength vs frequency across the entire band. It connects to your computer by USB 2.0 and with the companion Windows software you can display the spectrum or save the raw data to an Excel compatible file for some more number crunching. It uses just two significant components, a radio module from Cypress Semiconductor and a PIC microcontroller from Microchip. Total cost to build it should be less than US$30. The 2.4GHz Band The 2.4GHz ISM (Industrial Scientific Medical) band is often called the WiFi band because it is used for WiFi networking (ie, 802.11 b/g/n). This band is unlicensed, meaning that you and anyone can tran...

This is a Simple1.5.4.5V to 9V Converter Circuit Diagram. Build a Simple1.5.4.5V to 9V Converter Circuit Diagram. 1.5.4.5V to 9V Converter Circuit Diagram 1.5.4.5V to 9V Converter Circuit Diagram

This is an example of efficiently driving a 1 watt white LED from a 12 volt battery using a buck converter. The LED could simply be connected with a series resistor to get the desired current, but the efficiency would be only 25% since the resistor would drop 9 volts while the LED only requires 3. The buck converter provides about 90% efficiency. The idea is to establish a circulating current through the inductor, diode and load, while the switch replenishes the lost load energy on each cycle. The duty cycle of the switch will be the output voltage divided by the input voltage, or about 3/12 (25%) in this case. It's actually a little greater since there is a small (2.2 ohm) resistor in series with the LED that drops about 0.5 volt, so the total load is about 3.7 volts and the duty cycle is around 31%. The circuit could also be used to charge AA batteries from a 12 volt source with adjustment to the duty cycle. The driver section uses a CMOS hex inverter (CD4069) where two of the in...

      In this article we learn about a 1 Watt FM Transmitter amplifier with a reasonably balanced design specified to boost a RF frequency in the 88 – 108 MHz spectrum.             It may be considered a fairly sensitive configuration when used with quality RF power amplifier transistors, trimmers and inductors. It involves a power amplification factor of 9 to 12 dB (9 to 15 times). At an input power of 0.1W the output may be well over 1W. It's advisable to choose T1 transistor on the basis of the fed voltage. Considering you possess a 12V power supply in that case using transistors like: 2N4427, KT920A, KT934A, KT904, BLX65, 2SC1970, BLY87. At 18 to 24V inputs you may want to use transistors such as: 2N3866, 2N3553, KT922A, BLY91, BLX92A. You could also consider using 2N2219 at 12V However that would yield just an output power of 0.4W at the fullest. How to Calibrate this 1 watt fm power amp Initially don't appl...

Build a 1.2-36V 5A Adjustable Power Supply circuit diagram with LM317 . This circuit is a simple power supply circuit. 1.2 - 36V adjustable bench power supply with 5A of output current. Max input voltage is 37V and output is adjustable via potentiometer between 1.2 up to 36 volts. TIP147 PNP darlington transistor boosts the current of LM317 from 100mA to 5A. LM317 is the most useful and inexpensive adjustable regulator and for this circuit you can also use LM317 L that can give 100mA, that's enough for transistor bias.   1.2-36V 5A Adjustable Power Supply Circuit Diagram  D1 and D2 are protection diodes because when you turn the circuit off the output capacitors are discharging and can damage the transistor or regulator. 100nf capacitors are in parallel with electrolytic capacitors to remove high frequency noise because large value electrolytic have large ESR and ESL and can't remove high frequency noise.

ADJUSTABLE 1.5A STEP DOWN 1.5MHz SWITCHING REGULATOR ELECTRONIC DIAGRAM However, an Adjustable 1.5A Step Down 1.5 MHz switching regulator circuit can also be used to overcome such problem. It uses ST1S03 step down DC-DC converter. The ST1S03 can also be used to power low-voltage digital core in HDD application . With input voltage range 3V to 16V, the ST1S03 can gives current up to 1.5A. The circuit can use tiny surface-mount components due to an high switching frequency (1.5 MHz). Resistor divider is used to set the output voltage value. Components needed to build the divided are capacitors (2 pieces), schottky diode (1 piece), and inductor (1 piece).

Want to avoid the problem of carrying three different flashlights to perform a test? Why don’t you try integrating Ultra Violet, Infra Red and visible light together in one flashlight? Read on to know more about this. The multi-tasking flashlight is basically composed of a metallic case, a switch, cables and connections, four 9V batteries and three different LED heads that provide the desired light beam. For the construction of this flashlight, LedEngin’s LZ4-40 is recommended. This comes with a very wide wavelength that includes infra red and ultra violet light. Distinct visible light color temperature can also be found The first step is to build the body of the flashlight, using an aluminum tube. Next come the drilling and cutting for switches and covers. Once the body is finished, the work on the constant current driver should be completed, adding the proper terminals for the batteries and the base for the LED heads.  Once all the power source wiring is completed and insulated w...

                                     This is the circuit diagram of adjustable symmetric 1 to 24VDC, 1A Power Supply. This power supply give dual output positive and negatif output, you can adjust both positif and negative output (+1 to +24VDC and -1 to -24VDC). This kind of power supply also known as dual polarity power supply or splitted power supply which give positive anf negatif output. This power supply can be used for universal usage, which required not more than 1A DC current. Please take a note that you should adjust the output voltage using general multimeter or DC voltmeter before use this power supply to protect the supplied devices. Circuit Features: Low cost universal symmetric power supply Just add a suitable transformer and a heatsink Ideal for e.g. op-amp applications, amplifiers, … Trimmers...

Some of you may remember me mentioning the 1963 Hofner Colorama II (also known as the Hofner 164) that I bought a while back on ebay. What do you mean you don’t remember? I posted about it right here: http://diystrat.blogspot.com/2008/11/my-first-ever-electric-guitar.html Oh wow, was that really three years ago? Who knew? Anyway, as is always the danger when you buy something without seeing it in person first, especially a 50-year-old guitar, you never really know what sort of shape it’s going to be in. The photos showed a guitar that appeared to be in fairly average shape for its age and most of the original parts seemed to be there, but upon closer inspection it appeared that this particular guitar needed a lot more work than originally anticipated. In fact, I don’t think there’s a single part of this guitar that doesn’t need work in some way or another. In that previous post, I mentioned that I completely messed with my original Hofner Colorama II almost 25 years ago, and so I feel ...

Except for use as a normal Battery Charger , this circuit is perfect to 'constant-charge' a 12-Volt Lead-Acid Battery , like the one in your flight box, and keep it in optimum charged condition. This circuit is not recommended for GEL-TYPE batteries since it draws to much current. The above circuit is a precision voltage source, and contains a temperature sensor with a negative temperature coλficient. Meaning, whenever the surrounding or battery temperature increases the voltage will automatically decrease. Temperature coλficient for this circuit is -8mV per °Celcius. A normal transistor (Q1) is used as a temperature sensor. This Battery Charger is centered around the LM350 integrated, 3-amp, adjustable stabilizer IC. Output voltage can be adjusted with P1 between 13.5 and 14.5 volt. T2 was added to prevent battery discharge via R1 if no power present. P1 can adjust the output voltage between 13.5 and 14.5 volts. R4's value can be adjusted to accommodate a bit larger or s...

 Google introduces its tablet the Tango Project, a project that handles allow you to create 3D maps of the environment of a mobile device. The Project Tango Tablet, as Google calls it for now, is mainly designed for developers interested in exploring the future of 3D technology on a mobile device can do so and to develop new features that may allow it to another level bringing this technology, as mentioned Google. The 7-inch tablet that goes on sale later this year is priced at U.S. $ 1.024, making it not the cheapest in the market. However, Google's tablet was created with help from Nvidia to allow create internal maps of buildings in 3D, thanks to various cameras and sensors that are in the device. The tablet has a Nvidia Tegra K1 processor, 4GB of RAM, 128GB of storage, Wi-Fi and 4G LTE. Although the Tango Project or Project Tango would be in its initial phase, the new tablet could help take an important step for this kind of technology can reach consumers in the future.

Power supply circuit to generate output below were variations between 1.3V DC to 12.2V DC with 1A current. In addition, the power supply circuit is also equipped with over-current protection or shield against belebih flow. Power supply circuit is very simple, but the quality is quite good, made her basiskan regulator IC LM723 is a pretty legendary. Description: R2 to set the output voltage. The maximum current is determined by R3, over-current protection circuit inside the LM723 to detect the voltage on R3, if it reaches 0.65 V, the voltage output will be off her. So the current through R3 can not exceed 0.65 / R3 although output short-circuit in his. C3 and C4 are ceramic capacitors, as much as possible directly soldered to the PCB, this is because the LM723 is prone to oscillation that is not cool. LM723 works with 9.5V input voltage to 40 V DC and the LM723 can generate its own current of 150mA when the output voltage is not more than 6-7V under input voltage. Specifications: Output...