Questions tagged [digital-input]
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17 questions
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How to properly handle floating input on an optocoupler LED with long wires in automotive environment?
I am working on a circuit that uses a PC817 (or LTV-847 for multiple channels) as an input stage for my microcontroller (via MCP23017). The installation is in an automobile, and the input comes from a ...
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Photointerrupter RPI-0451E using 24V connected to PLC input
The following circuit works with 24V and is to be connected to a PLC input:
It works fine with Signal Out disconnected, I have around 1V when light is not cut and around 22V when light is cut.
But if ...
- 293
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RC switch de-bouncing, for MCU digital input
Does this simple 3 component circuit-snippet, provide a debounced digital input for the mcu?
so based on the switch mode, the input is either High or Low, but with a delay (since the caps are there) ...
- 313
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Universal PNP/NPN (2-wire / 3-wire, 5 – 24 V) isolated pulse-count front-end – sanity check
I’m about to freeze a little front-end that will live inside a loom monitor.
The same box may be plugged into very different textile machines, and I’m tired of keeping two versions of every board (one ...
- 629
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Digital I/O circuit with optocouplers on PSoC5
I’m working on a project with a PSoC5 and need to isolate 24V digital signals (both input and output) using optocouplers. I’d like to know if the circuit I’ve designed is suitable or if there are any ...
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How does a remote controller know which button was pressed? [closed]
I disassembled one of my remotes to see what's inside, and saw that lines connected to different buttons connect to each other also. Whenever I use buttons in my own circuits, I connect each button to ...
- 881
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How does this industrial camera's digital input circuit work?
Industrial cameras I use have a GPIO pin which looks like this when used as an input:
Source:
https://docs.baslerweb.com/circuit-diagrams-(basler-cameras)#gpio-input-line
I'm curious about how it ...
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Using 1.8V digital signals with TPS281C100A and AP22653A
I plan to use the following two devices: AP22653A and TPS281C100A and drive the enable pin from 1.8V logic. They are specified for minimum 3V3 operation, but for both inputs the VIH is 1.5V. Would ...
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Isolated digital input for large variable input voltage (12-240)
In industrial applications, relays are used to send the signal to other parts and machinery. They switch 24 DC and 220 AC on, off signal.
Although there are plenty of circuits to read input signals, I ...
- 345
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Voltage divider with serial resistor connected to BOOT1 pin from STM32F10X microcontroller
I was viewing a circuit in a schematics that is given to me. I found this voltage divider with a resistor connected to the BOOT1 pin from a microcontroller:
NOTE: BOOT1 is connected to the BOOT1 ...
- 891
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876
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4-20mA analog output into a digital input?
I'm measuring the 0-10V pressure output of a pressure sensor with a LOGO! smart relay (PLC). I would like to make sure that the pressure sensor is working even when I'm measuring nearly zero values ...
- 35
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3
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What does "strap input" mean as applied to the DS90UB960WRTDRQ1?
I am using a DS90UB960WRTDRQ1 in my design. In the pinout functions the definitions of the I/O pins are given as shown below:
What does "strap input" mean? What is the difference between a ...
- 4,445
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Digital Input Voltage range selection
I am designing 24V industrial shields with 4 channel Digital Inputs. the digital inputs voltage range shall be set by 1P3T switch wherein the switch shall be actuated between 3 voltage ranges of 0-24V,...
- 129
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Do all logic circuits have to have negligible input current?
There are common configurations where, for example, a logical HIGH input (a voltage source) is connected to the input of some logic circuit through a resistor as shown there. Typically this logic ...
- 163
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How to determine the signal direction in Altium Schematic?
I have 5 signals as digital input. We can think of them as a simple button. They hook up to PCB via a connector on the card and I want to show them as a port in the Schematic. How can I determine ...
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