I have an autoranging multimeter and many AA batteries.... how do I interpret the readings when deciding to keep or discard AA (1.5 volt) batteries?

So I've been reading a few threads here and on other forums. I understand there are various solutions for stepping down or up a voltage. What I have found are the LVC series shif …

I found a sensor recently that emits ±90V (AC) on stimulus. How would I go about reading this from an arduino? Update I didn't think there were so many options. :) The kind of …

Pat asks: Accelerometer Breakout Board - ADXL193 +/-250g could you tell me if this is correct. Looking at the data sheet the mid sensitivity is about 8mv/G @ 5volts. If I use a …

How do most voltage regulator ICs work? Are they the same as hooking up a variable resistor and a voltmeter and turning the knob until you get the desired voltage?

I have a bunch of green LEDs (not super bright), the plastic around the actual LED is physically green, but they did not come with a turn on voltage. 3V seems to work but they're n …

I'm trying to interface a 3.3v I2C device to a 5V Arduino. I don;t have a problem with the SCL line - I can use a simple voltage divider but I have an issue with the SDA line as th …

I have a relay operated by an NPN transistor that needs some voltage applied to the base. I'm working with an arduino and if I give it a digital port, all's well. The circuit loo …

I am designing a circuit that needs to output 5VDC @ 1A. I'm trying to use a wall transformer to step the voltage down to 12VAC. The next step is the diode bridge and ripple capa …

I am trying to build a robot and i have been having trouble getting a working h-bridge for my motors and i was wondering if anyone could help me work this out. i have 2 motors to …

I'm looking to power a remote controlled car with a solar panel on its back. What size to power am I going to get? Is there one light enough that it wont slow the car down?

I need to make a voltage level shifter. it needs to translate a TTL logic level into a 12v logigc level. what I've done is to apply the 5v at the base and 12v Vcc and to take the …

Hello all, I am building a distance sensor..I have the ucontroller portion done. I was going to use IR to reflect a beam and get a proportional analog voltage to estimate distance …

Hi How can I implement (or maybe there is an IC that already does that) a board whose input would be I2C and output would be analog voltage (0V - 5V) ? Eventually I would like to …

I am looking to power a PIC microcontroller with a supply voltage that ranges from 4.5V to 18V. This will be a battery powered device so I would like to conserve power, ie. linear …