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Hello We wish to sense 200mA of current max in a led drive circuit and there will be 200v of potential between the current sense bit and the output signal bit. No Hall sensors seem to do low these are all up to at least 20A
Hello We wish to sense 200mA of current max in a led drive circuit and there will be 200v of potential between the current sense bit and the output signal bit. No Hall sensors seem to do low these are all up to at least 20A
Hello, Is this so? ("direct drive led" means the leds are connected direct to rectified mains with no switch mode driver used...instead some special switchs are used to simply switch in (and then out) more leds as the mains half sine rises and falls at 100Hz) The below article says that "centralised" (...)
hi every one, I'm using a circuit which has 2 7segment but I use 7 leds instead of each 7segment. this 7segments shows numbers from 10 to 35 and because of supply current limitation Just 2 leds can be on each time so I have to use PWM signal to turning on them. Consider I want to show 28 so 12 leds should be on and as I mentioned just 2 (...)
HI Anybody knows about this board details? mean connection and working code... I got 5 board from a dump yard and its working good.. (all display) But not got the controll board.... anybody knows about this board? Thank in advance..
It's a standard monochrome led-board design. There are loads of microcontroller projects showing how to drive similar display boards. Presuming the latest decoder circuit is correct, it's a 1:16 mux scheme. Respectively I would expect either 16 rows x 96 columns or 32 rows x 48 columns led matrix. The difference only matters for data (...)
133629 Is it ok to add a potentiometer parallel to constant current source(CL2 see attachment) and led to reduce the led intensity(see my schematic in attachment). or if i am going to use TLC5916 to drive 8 Parallel led 133633 and add parallel potentiometer to each led to reduce the intensity manual
In my project i used 1K resistor as pullup resistor for pic microcontroller on PORTB and enabled internal pullup resistor also... is 1k is suitbale for pullup operation..? Or i need to change the value...?
My solar garden light has a 1.2V battery but the DC to DC converter in it boosts the 1.2V to about 3.5VDC to light the colors changing led. It does not have a DC amplifier. My audio amplifier amplifies the tiny signal level from my MP3 player so that it can drive a speaker. It does not have a DC to DC converter.
Sounds complicated and if you intend to run one I2C bus around them all you will run out of addresses, bus drive capacity and speed. What are the IR phototransistors detecting? Most need a fairly 'bright' IR source before they give significant changes in their current and that current has to be detected somehow. Cheap RGB leds can be just as goo
Depending how you drive or switch the leds you may be able to sense a day/night condition by using the photo-electric properties of an led. The sensing can be done during the off cycle.
A TIP120 is not a single transistor, it nis two transistors connected as a darlington. Your circuit has nothing to limit the led current so the leds will blow up. The maximum allowed current in a TIP120 is only 5A so you should use a powerful Mosfet for 25A.
Besides wrong mux counter output polarity, if you want to light more than one led in a column, the series resistors should be connected to the row rather than the column transistors, otherwise the current will be shared by a varying number of leds and cause intensity variations.
I have used a 555timer to output a pulsed signal. The amplitude is 4.6V. I am then inputting this signal into a transistor to pulse the led. However when I do this the amplitude drops to 0.8V. How do stop the amplitude from falling when I put it through the transistor? :?:
Hello, I have designed a 12v voltage regulator on a breadboard. I can adjust the voltage using a potentiometer. I want to add a led which lights up only when the voltage is 10v. Below that, the led is off. I want to use the led as an indicator that the voltage is equal or more than 10v. I have attached a schematic of the voltage (...)
I wanted to try and increase the range of my TV remote. I do not have any infrared leds and cannot get them easily, however I can get a lot of bright leds and I can build an amplifier circuit. Now I know that a TV responds to IR, but would a very bright led produce enough IR to trigger the sensor in the TV?
Hi, I am working on a led tube driver circuit sample. Basically I am trying to reversing the circuit just for simulation purpose. So, the basic blocks of the circuit consists of: AC input - Bridge rectifier - EMI filtering - Buck Converter - Controller IC for Buck - Output. Now, I am having trouble finding the controller IC, which is a 6 pin
Hi folks, new in this forum! I was design a circuit using as pilot strobe lights for my UVA/drone. When power on, all led light up with 100 % brightness level. Ater 3-4 second, the pattern from my Nano started, but only with 20 % brightness. If connected other power supplies, else two 3400 mAh Li-Ion battery in serie connection, just a littl
Hi there, I have 7 segment common cathode display, each segment look like on attached image, 5mm red color I will use 12VDC to drive it, total 2 seven segment common cathode display, for countdown show...
Your block diagram is insufficient. Each digit needs to drive 4x160mA with constant voltage ( either common Anode or COmmon Cathode) which is multiplexed to give 1/4 of the average max current of 160mA per digit. Then each segment must be current limited by a resistor drop including ESR of driver, Vf of led @20mA and Vdrop of digit (...)