Using the LM3551 and LM3552 are fixed frequency, current mode step-up DC DC converters with two integrated NFETs we can design a very simple and high precision LED brightness control system. The devices are capable of driving loads up to 1A from a single-cell Li-Ion battery. The LM3551 and LM3552 can drive one or more high current flash LEDs eithe
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r in a high power Flash mode or a lower power Torch mode using the TORCH FLASH pin. A programmable Timeout function on the FTO pin forces the internal NFETs to turn off after a certain user defined time. An external SD pin (LM3551) or EN pin (LM3552) is available to put the device into low power shutdown mode. During shutdown, the feedback resistors and the load are disconnected from the input to avoid leakage current paths to ground. The RT value for this LED driver circuit is 17 ohms and the value for the RF is 6. 5 ohms. The output current for IFlash is 250mA and for the ITorch is 75 mA. Some of the features of this LED driver electronic project are : flash timeout protection, independent Torch Flash Shutdown modes, LED disconnect in shutdown, programmable soft-start limits inrush current, over-voltage protection, wide voltage range 2. 7 to 5. 5V, 1. 25MHz constant switching frequency.
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
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The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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