# Questions tagged [input]

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

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### Peculiar input current

http://www.cheemi-tech.com/product-current-transformers-CMPT107.html Voltage between B & C is 119V which is equal to 1.19mA but input current between A & B is 14mA. Why is it so? Edit: In ...
615 views

### Voltage time graph integration

In a Voltage time graph , at constant current I= 170 amps, voltage=0 to 5,5 and time= 0 to 97 sec and voltage decreases from 5,5 at 0sec to 1,16 at 97 sec, now how can I find the total power ...
234 views

### Detect 230VAC or 12VDC in the same pin [closed]

I'm designing an input interface for a microcontroller (uC). Want to detect signals (only want to know if there is voltage or not) of different typology, so you can have in the same input to the board:...
111 views

### prox sensor with NPN open collector output or a dry contact

I am totally new in this field. I want to use a 5 V / TTL signal from a National Instrument to switch on/off a Red lion PXU series temperature controller. But this controller required a dry contact ...
87 views

### Input power vs charge curve (battery charging) [closed]

I want to know when charging a battery whether the charger reduces its current input as the battery reaches 80 percent charge, because it takes longer to charge the battery due to the charge curve. ...
129 views

### Read state from LED in another circuit

For a current project, I have to read the state of an LED in another circuit with a Raspberry Pi. My current schematic is this: simulate this circuit – Schematic created using CircuitLab ...
56 views

### PIC16F883 over 12V input with resistors?

I am using a ADM00308 with a MTS2916A driver development board from MicroChip. There is a serial port RX & TX which can be programmed into an input. I'll use those inputs to drive the motor a ...
451 views

### Resister Parallel to AC Live & Neutral

Hi Guys, I am a newbie to electronics but love to get started learning. So after a few google searches and YouTube videos, I have decided build my own variable Power Supply using an old Computer ATX ...
364 views

### How can I design an isolated, wide-range digital logic input compatible with AC and DC voltages from (say) 5V-300V?

There are some excellent suggestions on how to create a wide-voltage range digital logic input on this question. The question is very similar to my needs. I'd like to be able to detect the presence ...
157 views

We are designing analog input with RC low-pass filter and we want to be able to disconnect the filter if needed. So we came up with these two options. 1st option has jumper at the right side and has ...
76 views

### what is the minimum current sinking capability for pic

what is the minimum current sinking capability for pic16f18854? also i need to connect input switch to the pic.i have tried making my own and assuimg suitable data.please help me is this correct.need ...
39 views

### Do I need different isolations among long-wire switches?

I'm playing with an MCU board (like Arudino) to read the state of several switches in my home (i.e. magnetic switches). The wires between the sensor and the board are quite long: 15+ meters in a star ...
73 views

### Arduino NANOs sharing input signals and controlling Pixel Ring blowing up

We're a bit stuck on the following problem : We've connected a bunch (18 to be precise) of Arduino NANOs on the same +12V supply and they all share the same PWM output from another device (which goes ...
315 views

### Error: illegal Verilog output port specification

I am having problems with my verilog test bench. Every time I try to run it, I get the error in the title above for my four switch registers. I have searched this question numerous times but I cannot ...
246 views

### Differences between flip-flop control inputs and clock inputs

I'm studying clocked flip-flops (FFs). However, I cannot differentiate between the two terms control inputs and clock inputs. Can you tell me the differences between those two types of inputs, or ...
1k views

### MCU Input Protection

I am working on a simple protection circuit for an I/O pin on an MCU. The device will be 3v battery powered. The MCU's I/O pin has a voltage tolerance of (GND - .6V) to (Vdd + .6V). Pull-to-ground ...
101 views

### What does “LB” out mean in a DC-DC buck converter?

Teacher gave me a schematic,and it includes a DC/DC buck converter with "LB" input and output,but i have no idea what the "LB" is,so i want to ask that does someone know what may the "LB" be?
78 views

### Wide Voltage Automotive Status To Microcontroller Input

I need to monitor the status of a wire in an automotive application that can have 10-40VDC on it at any time. What is a good approach to limit the voltage to a microcontroller input across such a wide ...
85 views

### Input of boost converter or charge pump in the energy harvest [closed]

I read some paper about the energy harvest, and lots of paper said the induced voltage from, for example, the thermo-electric harvesting could be as low as tens of millivolts in a realistic case, so ...
79 views

### ST10F269Z2T3 abnormal Input Logic Levels

We are using a ST10F269Z2T3 Microcontroller (Datasheet) in one of our old Designs. Among other things, the ST10 monitors the functionality of external devices using Standard logic Inputs. Eg.: Input ...
141 views

### Tristate driver I/O for analog signals

In FPGAs a tristate drive is used to convert a pin from an input to an output or vice versa. Now this works only in digital circuits. Is there a way how you could obtain the same functionality of ...
414 views

### Wide voltage range input regulation (24V - 3.3V)

TL; DR: I need a circuit capable of handling input voltages from 24V to 3.3V (with a 10mA/5mA maximum current) and delivering 3.3V to the microcontroller (ESP32) input. Recently, I've been working ...
118 views

### How I can get a high level with this circuit? [closed]

simulate this circuit – Schematic created using CircuitLab I have this circuit. The MCU on the right select speaker output if I have a low level and if i want audio jack output, i need a high ...
36 views

### Maximum input capacitance of IO-Link-Device on C/Q

I have a bit of trouble understanding the IO-Link-specification concerning the input capacitance of the C/Q-pin. The specification says in table 7 (line 754): CQD Input capacitance min: 0 max: 1,...
90 views

### How would you calculate the input and output impedance of this amplifier?

How would you calculate the input and output impedance of this amplifier? I have done a lot of research and found so many conflicting pieces of information. Not sure what is right. C1 = 10Uf, C2 = ...
138 views

### Input circuit for ESP8266

I built the following simple circuit as an input to an ESP8266 microcontroller: When I hold the switch closed, the input goes low. How do I modify this circuit to do the opposite? I want to press a ...
405 views

### Associate std_logic_vector constant with input port VHDL-200X

I am trying to configure a chip over SPI interface using FPGA Spartan 6 Eval board. I just need to configure, I do not need to read the data from the chip, it will be done by another interface. ...
104 views

### Powering 5V IC with 3.8V

I'm trying to power a ESP8266 and ATMega128 from a LiPo battery via the TP4056 charging module. I get 3.8V out of the charging module. According to the ATMega128 Datasheet it is possible to power the ...
2k views

### in SPI, can MOSI and MISO be connected together?

I'm using an 8051 series microcontroller, and documentation states that if I use serial mode 0, then its RXD pin can function as a bi-directional pin (both input and output) while TXD is strictly a ...
93 views

### Input voltage limits of AD8495 (thermocouple amplifier) vs supply voltage

I'm working on an android multigauge for cars based of a pic microcontroller. Some inputs from sensors are not fed by my circuit so after stumbling upon this thread: http://www.microchip.com/forums/...
95 views

### What is a “current load” on a 24 V input used for?

The MAX14821 (datasheet) is a 24 V IO device that features selectable current loads for use in actuators on the inputs. What would this be used for? It's not just ...
153 views

### Audio ADC voltage level SNR question

I keep looking for Audio specific ADCs and the majority of these devices work at low voltages on the analog circuitry (5V for example). Lets say we want to process an higher voltage audio input ...
223 views

### Connecting a coin receptor to a key press

I want to connect a coin receptor to a keyboard press. I want to have an arcade cabinet with my computer game running. It should only add credits when a specific key is pressed, which can be ...
2k views

### 12 V input on 3.3 V GPIO, TVS pulled down or Schottky pull up?

I am building my own PLC that has to accept permanent inputs of up to 30 V DC into a STM32F with 3.3 V inputs. The switched input will have to work with 8-30 V, but 90% of the time the ...
475 views

### designing a universal 0-10v and 0-300k resistance input circuit

I'm trying to design a universal input circuit which can accept 0-10v as well as variable 0-300k resistance. I'm using this ADC (mcp3008) which has a maximum input of 5 volts , couldn't find an ...
91 views

### Can I use a similar AC adapter with different input but the same output?

I have a landline telephone from Japan. The owners manual says only use OUR AC adapter, {Input 100v 50/60Hz 8VA - Output DC 11V 430mA} I want to use this in North America - can I use a AC adapter ...
911 views

### Vbe vs Ic characteristics of NPN transistor at different Vce in active region

Below is an NPN transistor characteristics for Vbe versus Ic at different Vcb or Vce: It seems like in the active region, Vbe vs Ic curves gets steeper with an increasing Vce. The following ...
2k views

### stm32f4 vdd and interfacing input pins

The stm32f4 discovery datasheet DS8626 specifies vil and vih as below So I have some questions based on the documentation How do I know that what value VDD is operating at if I use the usb to power ...
301 views

### AT32UC3C Negative ADC Input Voltage

The AT32UC3C ADC can be set up using either internal or external references as seen in Table 36-8. For any type of voltage reference used, the datasheet suggests that the ADC is capable of converting ...
121 views

### Signals shorted when connected to the input of an unpowered IC

I use one SPI bus from CPU to two FPGAs with different (i.e. individual) CS signals. The CPU and first FPGA are powered up, and the second FPGA is unpowered. When I send SPI signals to both FPGAs, ...
338 views

### PIC16F15345 Microcontroller, RA5 Digital Input Pin Issues

I've been having a very strange problem with my PIC16F15345 microcontrollers. I'm trying to read a digital input state from a specific pin on the microcontroller (Pin2, or RA5). My setup code is below:...
138 views

### Diode populated keyboard matrix: Wire two separate buttons to the same output?

I have an encoder board for a 16x8 row/column switch matrix. An absolute beginner to electronics but using all of the great online resources for research the best I can. However, occasionally it turns ...
43 views

### How to decide maximum input current required in linear charging method?

I am using MCP73213 IC for my charging application. I would like to use the maximum capacity of the IC for charging. i.e., 1 ampere charge current during constant current charge cycle.And input ...
298 views

How can I find the minimum analog input voltage for an oscilloscope? I've checked the datasheet for the particular one I am using(Agilent DSO-X 2002A) and only the maximum input voltage is listed.
540 views

### Sallen Key topology input and output impedance

Ideal Operational amplifier Zi=(R1+R2)||Zc2 Zo=0 741 Operational amplifier Zi=(R1+R2)||Zc2 Zo=0 (at DC) For the input impedance when using a 741 I am not sure if I should consider the Fairchild ...
129 views

### harvested a joystick from a fight con, want to use it to take input into an arduino. how do I wire up the switches?

the joystick is just 4 switches around a shaft (up, down, left, right)- 0, 1, or 2 of them are engaged depending on direction the joystick is being pulled. here are some images showing what I'm ...
347 views

### Can you use a stepper motor as input?

I'm not too versed in EE so I apologize for my duncitude - My thought is that you can precisely control a stepper motor, but can you inversely get precise readings out of a stepper motor? For ...
548 views

### Audio input: stereo to mono and filtering DC

I have to get an audio input from a PCB 3.5mm jack and summing right and left channel into one (mono). Then, I have to filter any DC noise from the input. Resistors are 1kOhm each. This, for now, ...