Something put into a system or expended in its operation to achieve output or a result

learn more… | top users | synonyms

0
votes
1answer
43 views

Understanding the input specifications for a laptop adapter [closed]

The sticker on my laptop adapter claims the input should be INPUT: 100-240V~ 2.5A(2,5A) 50-60Hz What does all this mean? Here are a couple specific questions: Can the adapter accept anywhere ...
1
vote
0answers
86 views

Should my external analog input be isolated?

I want to build a device that samples analog signals from various measurement instruments via their analog outputs. The instruments have their own power supply, and all devices are powered from the ...
2
votes
1answer
78 views

What is the use of dual differential amplifiers in audio applications?

Why do audio amplifiers use dual differential pairs sometimes? Is there a mathematical justification and not just "the joy of symmetry"? Any hints, especially with some math would be of great help. ...
2
votes
3answers
156 views

What kind of metal are the legs of resistors made from?

Can anyone tell me what kind of metal is used in electronics to make wires going in/out to the elements? Can longer of this metal wire be found anywhere? Actually I am looking for sth like copper wire ...
0
votes
3answers
65 views

How should a SPDT switch be wired for a digital input?

I want to connect a switch to a digital input on a logic board and make it so that the input goes high when the switch is pressed. I'll be using a SPDT switch: Should I connect the digital input to ...
1
vote
2answers
67 views

Need an extra pin to control my driver board

I've been searching for a way to add an extra pin to a driver board. The MCU board that i'm using only has 8 pins on the left side and i'm already using all of them. 2 are for powering the driver and ...
0
votes
2answers
75 views

Inputs to a Wiimote using a microcontroller

I've seen various methods of grabbing inputs and sensor data from Wiimotes and Wii Nunchuks as standard Bluetooth HIDs into microcontrollers like the Arduinos, but is there a way of sending button ...
2
votes
2answers
84 views

What is the difference between digital input with low bias and digital input with high bias?

I have 3 inputs. Input #1 is low bias. I can hook up a 12V positive to input 1 and it will change it's state to 1 (or input is ON). Inputs #2 and #3 are high bias. Connecting a 12VDC to either of ...
1
vote
2answers
90 views

Invert PWM input with NOT gate

What practical advantages could there be in using a logic NOT gate IC (e. g. schmit trigger hex inverters) when compared to a simple NMOS + pull-up resistor inverter? I want to invert the PWM output ...
1
vote
1answer
149 views

How can I detect an open analog input pin?

Many of the Renesas micros have built-in support to precharge or discharge the sampling cap on analog inputs to be able to detect when the external circuit is disconnected. In the sample image, when ...
1
vote
6answers
171 views

Why is pin protection needed?

I have read this article about protecting input pins. One thing is still unclear to me — why is the protection needed at all with such a high resistance on the input pin inside of the ...
1
vote
2answers
76 views

How to create a circuit to reduce my H-Bridge Inputs from 4 to 2, much like the 4427 Dual Driver does?

My H-bridge is identical to the one here: http://www.robotroom.com/BipolarHBridge2.html I'm trying to reduce the number of inputs from 4-2 so I can control it with my arduino using the 2 inputs. In ...
0
votes
3answers
94 views

Custom PC input peripheral

I would like to somehow plug an extra button to my computer that when pressed would execute some shell script. Backstory: I'm a programmer and I very much wish I had a big red button to commence the ...
1
vote
2answers
204 views

Atmel Xmega ADC input voltage range - Can the ADC be damaged by exceeding it's reference voltage, if the input is still less then VCC?

I've been working with Atmels ATxmega parts a lot recently, and there is one question I still have that I have not been able to find a answer to, even after scouring the datasheets. Basically, The ...
-2
votes
2answers
68 views

Any ADC for 100ksps to 10Msps? [closed]

I have to sample 50 kHz signals having BW of ~30 kHz (35 kHz-65 kHz). For this purpose I'm looking for ADC's with Programmable Sampling rate ~100 ksps to 10 Msps Dual channel (14-bit) Can you ...
2
votes
1answer
98 views

How to work out or calculate this circuit?

I'm not an engineer, I understand a lot but I fail to understand how it works and how to calculate this for a 24vdc input:
2
votes
1answer
86 views

dsPIC 33EP128MC506 will not read RB8, appears to be software problem

I'm using a dsPIC 33EP128MC506. I have two PCBs with this chip, both displaying the same symptoms, implying it's not one-off damage. RB8 is definitely being driven to 3.3 volts, confirmed with a ...
1
vote
2answers
116 views

dsPIC 30F6012A will not read RD9, appears to be software problem

I'm using a dsPIC 30F6012A. I have two PCBs with this chip, both displaying the same symptoms, implying it's not one-off damage. RD9 is definitely being driven to five volts, confirmed with a ...
2
votes
1answer
200 views

Utility of two pins requiring same voltage

I have a LED backlight driver, which has input pin assignment as: Pin Function 1,2 12V Input 3 Brightness control PWM : 100Hz~20KHz DC : 0.5V~2.5V 4,6 ...
1
vote
1answer
139 views

Whats the name of a BMW iDrive type of encoder? [closed]

I am looking for a component that some people call a 7 way encoder switch. Basically, if you look at the center piece of the BMW iDrive, its that. It's a knob looking piece that if you turn to the ...
0
votes
0answers
137 views

Voltage detection / Universal uC Input => CLD, PTC

I'm currently developing a open-source "Home-PLC" for home automation. Every thing runs fine so far and I have a module with fixed voltage AC inputs and outputs. In the next step I want the build ...
1
vote
1answer
186 views

Arduino all input pins same value

Here's the situation: I have an Arduino mega 2560 and I'm trying to analogRead from 2 different pins. code: ...
4
votes
2answers
112 views

What is the use for non-inverting input resistance in a negative feedback opamp?

Here in the Figure R5=50K. This resistor value is not in the equations to obtain output voltage, and in many tutorials non-inverting input is directly grounded without a resistor. What might be the ...
3
votes
1answer
513 views

Problem Reading PIC18F4550 Input

Hi I am facing some problem with Reading the input from a PIC18f4550 , for a simple arrangement where when a switch on (switch = 1), few led should glow., and on releasing the switch the led should go ...
4
votes
2answers
647 views

PIC - How to skirt around low maximum ADC input impedance?

Reading a 9V battery on a PIC is nothing new. The most simple and straightforward way is with a voltage divider. I'd like to keep the divider resistances cranked up into the hundreds of kohms so I'm ...
2
votes
1answer
212 views

Recommended voltage/current for dry contact input?

What would be a reasonable value for voltage and max current to used in conjunction with a remote dry contact output so that it can return to my MCU (through isolator)? I plan on using this input for ...
0
votes
1answer
47 views

Differential Voltage Range vs. Clipping Level

The data sheet for the AD835 analog multiplier mentions that its inputs have a "Differential Voltage Range" of ±1V and a "Differential Clipping Level" of at least ±1.2V (typ. ±1.4V). What is the ...
4
votes
1answer
228 views

ATtiny45 pin change interrupt PB5?

On the ATTiny45 data sheets it states that PB5 can be used as a digital IO pin and I want to use it to trigger a pin change interrupt, my only issue is that it is also the reset pin and the moment I ...
2
votes
2answers
117 views

How can I get this to not read an arduino digital input?

I have been working on this for a while. It is a small part of a much bigger code. I have a digital input pin connected to a on/off switch and another input pin connected to a momentary push button. ...
3
votes
2answers
147 views

What does it mean for an input impedance to be “differential”?

In a specs of a data acq. device the input impedance is shown as "20 MΩ differential". Does that mean the measured impedance in diff input case? If so how can I calculate the input impedance for ...
1
vote
1answer
117 views

PIC (16F627A) inverted inputs

I'm having problem with inputs of my PIC. There is somethink like "default value" on all inputs set to logical 1 so if I want to change the state I need to pass GND. How can I turn it "otherwise"? ...
3
votes
1answer
344 views

Digital input ports of the dsPIC30F4011/4013 not working on the dsPICDEM 2 Development Board

I have a Microchip dsPICDEM 2 Development Board with two microcontrollers on it: a dsPIC30F4011 (Motor Control Family) and a dsPIC30F4013 (General Purpose Family). I'm programming in C using the MPLAB ...
1
vote
0answers
85 views

ADC Input Stage Impedance

I plan to use the TI ADS1178 (datasheet) ADC. The ADC specifies a "Differential Input Impedance" = 140kOhms (low-power mode). Would this input impedance be the same for single ended inputs when using ...
3
votes
2answers
211 views

How to limit negative voltage on uC input pin

I'm trying to design a pulse induction metal detector to increase my EE skills a little bit. I started to sketch out the transmitting stage, which is just a MOSFET that switches current through a ...
1
vote
1answer
145 views

CD40106 output voltage

I'm testing some CD40106BE from Texas Instrument, CMOS Hex Schmitt Trigger (Datasheet Here). Vdd = 5V (Pin14) Vss = GND (Pin7) Vin = 5V I measured a Vout = 3.8V on every IC I tested, with a Led on ...
1
vote
0answers
1k views

How to wire a button for input on an Attiny85 using Arduino code?

I am trying to "shrink" my arduino project to an Attiny85. But for some reason I cannot get an input button to work on the Attiny85? To simply the circuit and to make sure I didnt make a mistake ...
8
votes
1answer
235 views

What's mean these microcontroller pin input/output modes?

I bought an stm32f103ret6. When I saw the reference manual, I saw that it has several I/O modes. For input: floating, pull-up, pull-down For output: analog, open-drain, push-pull I have already ...
2
votes
2answers
4k views

What is a “dry contact input”?

I'm a PC software guy, a newbie to electronics. Recently, I've got a project in which I need to source for a DAQ that can provide dry contact inputs to an interfacing digital output controller. The ...
7
votes
1answer
713 views

How is this 5-24V input circuit working?

Since I require some kind of wide range input (going to a microcontroller) for a new project, I looked through some designs that are already in use (or were considered at some point) for other ...
0
votes
0answers
130 views

button input staying high?

I have a setup with 12 buttons. 10 of them connected to the arduino pins 0, 1, 6, 7, 8, 9 and analog 0, 1, 2, and 3 (these are all configured with pinMode as inputs in the setup-part of the sketch). ...
1
vote
2answers
104 views

A 4.8v reading on a loose pin 0?

I have a setup that demands that I use all my I/O's on my Arduino Uno R3 board - including the serial pins 0 and 1. So I've initialized those pins as inputs, but when I make a reading on pin 0 it ...
0
votes
3answers
184 views

Microcontroller I/O configuration

I have been using PIC microcontrollers and have been using MikroC for the programming but I am little bit confused about the ports. On a PIC16F84A the port is defined in mikroC as ...
8
votes
2answers
300 views

How can I check input of USB?

I have following wire as shown below, one end has male USB connector and other end has four wires. I know, when connected to laptop, the RED one acts as voltage source and BLACK as ground. If I give 2 ...
7
votes
1answer
422 views

Should I use a resistor between an input pin of MCU/CPLD and VCC/GND?

Some times, I want my MCU or CPLD to input a static logic. So, I choose to tie it to VCC or GND. The problem is that should I put a resistor in series to limit the current? I just think by myself for ...
0
votes
1answer
306 views

Connect different devices (Ground/Voltage mismatch)

To begin with, I realize that voltage is relative but I do not get how to get a common ground so that everything is relatively correct to go in and out of the chips. The picture summarizes the setup: ...
0
votes
0answers
72 views

Using TLP280-4 with STM32F1xx MCU

This is a continuation of my previous question. Olin Lathrop explicitly explained me the previous question, but also set thinking on the exact way of connection the optocoupler to a MCU input. I ...
2
votes
2answers
342 views

Bipolar Op Amp w/ Near Zero Offset?

My understanding is that if source resistance is low, a bipolar op amp has 10dB less noise than a JFET. I prefer the JFET op amps because the input offset is so low that you can eliminate coupling ...
4
votes
3answers
388 views

Using Single Ended Output with Differential Input by Grounding one Input

I am making a frequency generator using the AD9833 (programmed from the PIC16F876). I wish to use a Programmable Gain Amplifier to adjust the signal level before being sent to a power amplifier ...
0
votes
2answers
135 views

Continous rotary input?

I need something to work as an input for a rotary device. It must be able to rotate continously, accurate to a degree of rotation, and so that any extra full rotation will have no effect on the input, ...
0
votes
1answer
367 views

How to use the PIC16F628A's PORTA,4-7 as inputs?

I'm working on a countdown timer and I want to use the MSN of PortA for my switches. I'm using MPLAB. I can't use C to program the PIC because the collage taught us to program in decimal, and they ...