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1  Using Arduino / General Electronics / Re: Pros and cons of buck vs. CCR to drive high-power LED? on: October 18, 2014, 10:42:49 pm
which I think means that the 1.8V dropout will be fine (it will still leave enough voltage for the LED). Am I understanding that correctly?

Look at the datasheet Fig 2, if you have about 1.8V at VAK, then you have only about 250mA, you need about 7V overhead to get close to 350mA.
2  Using Arduino / Project Guidance / Re: line following robot project on: October 17, 2014, 08:41:57 pm
The Pololu QTR-8 reflectance sensors had two different output formats: the QTR-8A outputs an analog voltage between 0 and Vcc that can be measured by an analog-to-digital converter (ADC), and the QTR-8RC outputs require a digital I/O line capable of driving the output line high and then measuring the time for the output voltage to decay (which provides an analog measurement of reflectance).

Output format for the QTR-8A: 8 analog voltages ranging from 0 V to supplied voltage
Output format for the QTR-8RC: 8 digital I/O-compatible signals that can be read as a timed high pulse

Arduino Library for the Pololu QTR Reflectance Sensors
http://www.pololu.com/docs/0J19/all

QTR-8A and QTR-8RC Reflectance Sensor Array User's Guide
http://www.pololu.com/docs/pdf/0J12/QTR-8x.pdf
3  Using Arduino / Project Guidance / Re: Li-on batteries on: October 17, 2014, 12:45:17 pm
https://learn.adafruit.com/li-ion-and-lipoly-batteries?view=all
4  Using Arduino / Project Guidance / Re: IR receiver decoding on: October 07, 2014, 05:59:43 pm
Have you read this..

https://www.sparkfun.com/products/10266
http://allaboutee.com/2011/07/10/arduino-infrared-sensor-code/
The connection



Code:
int irPin=2;
 
void setup()
{
 pinMode(irPin,INPUT);
 Serial.begin(9600);
}
 
void loop()
{
 
  if(pulseIn(irPin,LOW))
  {
     //button pressed
     delay(100);
     Serial.println("You pressed a button");
  }
 
}
5  Using Arduino / Project Guidance / Re: Using H-bridge on: September 25, 2014, 06:34:38 am
I use dual H-bridge (aka 'full' h bridge) ?

Which  dual H-bridge that you used? do you have link to this  dual H-bridge ?
6  Using Arduino / Project Guidance / Re: How to configure a 4 hourly timer on: September 25, 2014, 06:21:51 am
have you read this
http://forum.arduino.cc/index.php?topic=223286.0
7  Using Arduino / Project Guidance / Re: PSTN/MODEM IC - Talk over Phone Line on: September 23, 2014, 07:43:14 am
IC
http://www.lsi.com/products/personal-connectivity/pages/data-modems.aspx#tab/tab1
Modules
http://www.cermetek.com/Catalog/High-Speed-Modems/
8  Using Arduino / Project Guidance / Re: RTC DS1307/IN1307 - Very innacurate time on: September 18, 2014, 08:29:30 am
The datasheets for the crystals I bought said specifically *not* to do that.  The heat of soldering can crack the crystal.
9  Using Arduino / Project Guidance / Re: RTC DS1307/IN1307 - Very innacurate time on: September 18, 2014, 08:16:42 am
Read this,
Quote
with some coding that improves accuracy from (typically) 5 - 10 seconds lost per day to maybe a couple of seconds a week or better.
http://forum.arduino.cc/index.php?topic=87846.msg686532#msg686532
10  Using Arduino / Project Guidance / Re: How to increase piezeo speaker range? on: September 10, 2014, 05:40:38 am
You may try Tweeter Speakers System like this with high power amplifier.
11  Using Arduino / Project Guidance / Re: Need a help. on: September 08, 2014, 07:21:21 am
Base on the datasheet, it have three pins, one is +5V another is Gnd, and the out is analog voltage from 1.2V to 3V
you can start using this code, attach the out pin to pin A0

Humidity output signal : (25 , 60% RH, the input voltage = 5V) Humidity 20 % 30 % 40 % 50 % 60 % 70 % 80 % 90 % 95% voltage V 1.25 1.50 1.80 2.00 2.20 2.40 2.57 2.75 2.82

 
Code:
/*
  AnalogReadSerial
  Reads an analog input on pin 0, prints the result to the serial monitor.
  Attach the center pin of a potentiometer to pin A0, and the outside pins to +5V and ground.
 
 This example code is in the public domain.
 */

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue = analogRead(A0);
  // print out the value you read:
  Serial.println(sensorValue);
  delay(1);        // delay in between reads for stability
}
12  Using Arduino / Project Guidance / Re: Need a help. on: September 08, 2014, 07:10:01 am
Please don't cross post.

http://forum.arduino.cc/index.php?topic=265592.msg1872872#msg1872872
http://forum.arduino.cc/index.php?topic=265635.msg1873198#msg1873198
13  Using Arduino / Project Guidance / Re: 5W or 10W Led Driver for RGB on: September 07, 2014, 10:53:38 am
You also can use PWM hardware IC.
For example, something like the TLC5940 offers 16 channel PWM control.
http://playground.arduino.cc/learning/TLC5940
14  Using Arduino / General Electronics / Re: DC DC inverter couple of questions on: September 07, 2014, 01:33:13 am
But with this DC-DC converter, you still need the High voltage coil.
look at the right side of the schematic, it connect to coil.
15  Using Arduino / Project Guidance / Re: 5W or 10W Led Driver for RGB on: September 06, 2014, 07:03:35 pm
3) ill look at both if you give me the names to look for for my specific need, keep in mind they are going to be flashing most of the time not steady burn
4) only  1/2 dim and 1/4 dim upon a push button input

When you said you need the LED flashing and dim, in arduino you have to used PWM, AnalogWrite() function.

With  AMC7135  you don't need MOSFET, you can control using Arduino digital out pin directly like this

This circuit show using 3 AMC7135 for higher current of about 1A, you don't need that you will driving it only 300mA.
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