My Light Diagram

The circuit described here is a step-up converter to drive 20 LEDs, designed to be used as a home-made ceiling night light for a child’s bedroom. This kind of night light generally consists of a chain of Christmas tree lights with 20 bulbs each consuming 1 W, for a total power of 20 W. Here, in the interests of saving power and extending operating life, we update the idea with this simple circuit using LEDs.  Power can be obtained from an unregulated 12 V mains adaptor, as long as it can deliver at least about 330 mA.  The circuit uses a low-cost current-mode controller type UCC3800N, reconfigured into voltage mode to create a step-up converter with simple compensation. By changing the external components the circuit can easily be modified for other applications. To use a current-mode controller as a voltage-mode controller it is necessary to couple a sawtooth ramp (rising from 0 V to 0.9 V) to the CS (current sense) pin, since this pin is also an input to the internal PWM com...

Here is a design guide from Linear Technology describing how to design boost power supplies that can work from as little as 0.7 volts. These constant voltage power supplies that can run off until nearly every last drop of power is consumed. [ ]

This circuit is a 5v to 12 DC-DC step-up converter circuit which is specially ideal for the usb powered applications. A usb has two current supply modes.Before deecting the connected device the maximum supplies is 100mA to the load.when recognizing device its increases the output current up to 500mA.the controller (LT1618) also provides two input currents modes 100mA and 500mA which is 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.

This very cool American Standard Stratocaster came in for a clean and a restring—normally a very straightforward job. However, it had been in storage for several years in a fairly humid environment and a lot of the metalwork, including the electrics, had become somewhat corroded. It actually looks OK from that distance. Here are a few close-ups. In addition to the dirt and grime, you can see that many of the screws have rusted quite badly. A quick test also revealed that the pots were scratchy, the switch was not working correctly and the output jack was making a lot of crackling noises. A look down the neck shows corrosion on the frets, so these will need a bit of a clean and polish too. Oh and... is that… blood? The only way to deal with this is to dismantle it, but before I do that I’m going to take some measurements since it was actually playing pretty nice and I don’t want to change that if I can help it. Measuring the saddle positions:     And the pickup heights: First...