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1  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 04:41:14 pm
the problem with that is that logic analyzer will not show if it's 5v or 10v only low or high.
2  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 03:29:13 pm
I have a saleae logic analyzer, but it only works trough 5v.
3  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 03:22:47 pm
I wish to have money to buy one. I'll try on some hackerspace or university.
4  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 03:17:13 pm
Usually you include everything in a schematic (like a block, resistor, lamp etc.) including the load element.
yup, sorry for that!

My current understanding of how to drive the Meanwell is following:
The main problem is that without an oscilloscope I can't see the signal and what my circuit is doing. I'll try to find one and take a look.
5  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 03:04:17 pm
it's a 12V walwart with LM317 regulated to 10v.

I just didn't understand why are you thinking I'm plugging 10v on collector. I'm not. PWM-10v is actually output to the other side of PWM Led Driver. Like GND-10V, PWM-10v is GND and the other leg is on 10v directly.
6  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 02:55:38 pm
with this exactly transistor circuit I first posted, It works fine without any pull-up. this is why I have 2 wires from led driver. one goes to 10v supply and the other to the transistor emitter.

I already tried ULN2803, it worked, but output voltage were lower than 10v, I think because of the diodes it has inside.
7  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 02:26:03 pm
It's a LED Driver. more specifically  meanwell ELN60-48P.

if I give 5v PWM, it dim to 50%. I know PWM is digital, and this meanwell design is terrible. it's how it works. I need 10V amplitude PWM signal.

I found these 2 examples(transistor and opamp) and want to have answers before decide which one is better.
8  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 02:20:38 pm
So, now I have 3 choices, normal opamp, transistor(and I invert on code analogWrite(pin, ~value)) and comparator.

I know nothing about comparator. I supply 2 voltages and opamp output the greater? How do I wire to have 10v PWM from 5v?
9  Using Arduino / General Electronics / Re: OpAmp or Transistor on: March 24, 2014, 01:13:49 pm
not so much. signalling is minimal.

On another forum, a guy told me 2 advantages using opamp:
- current source capability
- easy to adjust gain multiplier

what is current source capability?
10  Using Arduino / General Electronics / OpAmp or Transistor on: March 24, 2014, 12:30:59 pm
Hello folks,

I want to understand the best way to do a level shift from 0-5v PWM to 0-10v PWM. I made these 2 circuits attached. One using an opamp and the other using NPN transistor.

What is advantages/disadvantages of each one?

Thanks,

Wagner
11  Using Arduino / Networking, Protocols, and Devices / Re: Xbee frame ID best practices on: November 09, 2013, 04:09:02 pm
Sorry for resurrect this thread.

I was just thinking the same thing. I want to have a reliable communications among my XBees.

I want to make a queue of packets and remove only when I receive txstatus packets acknowledging delivery.

Some timeout, let's say 2 seconds. It's TCP/IP for XBee smiley-grin
12  Development / Other Software Development / Re: Porting of Arduino IDE 1.5.x for the ARMv7 Platform on: October 25, 2013, 02:29:01 pm
I didn't saw your post before.

But I was doing the same thing and I'm having the same problem smiley-grin But, I'm using an UDOO Quad board.

Thanks,

Wagner Sartori Junior
13  Using Arduino / Audio / Re: Why the Sparkfun Si4735 radio shield is all wrong on: March 25, 2013, 06:48:44 pm
The problem is sparkfun that is not selling breakout anymore. I'll have to buy an "adapter board" and solder by myself.
14  Using Arduino / Audio / Re: Why the Sparkfun Si4735 radio shield is all wrong on: March 24, 2013, 07:25:58 pm
+1... it's a shame sparkfun selling this shield as it is.

look, is all open-source. what do you think in developing our own si4735 board?

I'm not good at all designing PCB but I can help with the schematic. we can use itead studio and open source the pcb so anyone can buy.

a good start is AN383 of silabs that has some tips on design and a proposed schematic. another thing is to make a BOM on digikey and mouser to anyone can buy and solder by yourself.

I suggest using big SMD components to easy soldering.
15  International / Portugues / Re: Setar dados no arduino em tempo de execucao! on: April 23, 2012, 03:37:15 pm
VocĂȘ vai precisar mandar via precisar fazer via serial.

http://arduino.cc/en/Reference/serial

[]s

Wagner
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