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  1. X

    Power supply circuit ideas

    I have a project which required 3.3v (170mA), 5v (1.2A), 12V (not sure yet). For the 3.3v I am going to use an AMS1117-3.3 which is more then enough so this is not an issue. I have 2 questions mainly as follows: I want to use 8x of these stepper motors driven by 8x DRV8825 and I am not sure if...
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    What's the difference between 8 & 32

    Hello all, Ok so I have a project, I am not in a hurry to learn and the main purpose here is to learn. But I need to learn the right way. Basically my question is this... What is the difference from an Atmel 8 bit uC to an Atmel 32 bit uC from the Programmers Perspective? As in, what is the...
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    Choosing a Mosfet to switch an Electric Match

    Thanks Hero for your reply. I will read about these level logic mosfets later on but I have a feeling they switch on / off rather than turn on slowly etc... Regarding the 12W resistor, you are right. 1W should be enough because I'm only going to pulse 1A for 100 - 200mS Thanks :)
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    Opto Coupler Common Ground

    That's what I thought.. so is there any other way to protect your circuitry apart from using opto couplers and  2 different supplies? I must use only 1 car battery. Thanks for your reply too :) X
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    Wireless task taker device

    Welcome :)
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    Wireless task taker device

    Hi there, Ok I did this with the right parts in about 10 minutes. Very simple. You need to buy an Arduino. http://www.arduino.cc/ And either a Wifi Shield or an Xbee Shield. Let me explain in simple terms. The Arduino was designed to have small boards plugged into it. These boards can actually...
  7. X

    Choosing a Mosfet to switch an Electric Match

    Hi Guys, I have a couple of questions but I know you might be busy, I would appreciate ANY answer even for 1 question.  :-* I have a situation where I would like to switch an electric match. The typical trigger power for such a device is 12v 800mA - 1A. I have three questions for this. 1. I...
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    Opto Coupler Common Ground

    Hi Guys, As I understand opto couplers, their main use is to isolate a circuit from another,mainly for protection purposes. In my case I have an Arduino which controls a couple of shift registers (74HC595) which trigger transistors and I would like to protect the Arduino and the Shift Registers...
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    Powering a device with Ac and Dc

    ???
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    Powering a device with Ac and Dc

    Dear Friends, I am building a device which requires 12VDC however it can either be powered by a car battery which is already 12V OR by 12VAC (or maybe 16VAC) At first I thought it was simple because I can simply put a bridge rectifier and a 7812 and AC or DC won't effect my electronics. But...
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    Mixing Voltages

    Hello all, I have a project at the moment and everything is to work from a single 12V battery. Now I am using an Arduino which has its own 5V regulator. Since I intend to switch some ICs and a relay, I can't just power everything from this poor 5v regulator. Can I for example have a...
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    need design project

    Well why not use Arduino man? Its open source, you can build and modify it as you like without breaking any laws and you can find a MILLION projects using Arduino. It very easy to control too. I'd say that you can actually get up and running with the code in less than 4 hours. good luck
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    A Clean Output

    Hi Hero999, Thanks for your constant cooperation. There has been some development since the last post. So I intend to use an Arduino to connect it to a 74HC595 Shift Register. I will then use a PC817 Opto Coupler as this is fairly new, small and fast. I haven't thought about the output of the...
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    A Clean Output

    Hey Hero, Thanks for your reply.  Ok so basically I chose the wrong symbol when making the diagram. The current design is now slightly different. I basically have the uC -> Shift Register -> Opto Coupler -> Transistor The loads are all 12V 50mA so no need for large switching stuff...
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    A Clean Output

    I have a small update. A friend of mine just introduced Shift Registers to remove the grid thing.... any other ideas?
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    A Clean Output

    My dear friends, I am currently designing a circuit whereby using 16 pins of a micro controller, I would like to trigger 64 outputs using the attached schematic. I plan to do this by using a matrix style connection (8 x 8). The schematic only shows this using 6 pins (3 x 3) otherwise it would...
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    12 V to 3 V Question

    Thanks for your reply. Yes I know resistors are current driven but these mammoths are different. When you give them 3v, they draw 1A, but when you give them 3.5, they simply draw too much and burn (obviously because they need a resistor). According to the datasheet, these LED take 3V continuous...
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    12 V to 3 V Question

    Hi all, Sorry for a simple question but I need to be sure. I have a 12V 2A power supply (thus making it 24W). I need to power some LEDs which take 3V 1A (thus making each led 3W). Can I use a 7803 with heatsink for each LED with this power supply (upto a max of 8 LEDS? 3 x 8 = 24W) Thanks
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    Voltage / Frequency Powersupply

    I think I managed to make it work. Thanks for the help. However what if I still wanted to give it a try? As long as the output matches that of the original board (using an oscilloscope) I should be good to go. Thanks x
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    Voltage / Frequency Powersupply

    My Dear Friends, I have an old system which basically allows me to vary DC voltage and frequency such that the output is like a square wave in a function generator but which can take a couple of Amps. At the moment, I have a large transformer which supplies power to another variable transformer...
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