Questions tagged [device]
The device tag has no usage guidance.
141
questions
-4
votes
1
answer
134
views
Help in identifying an abnormal PCB found suspiciously [closed]
This is an odd PCB I found a while ago on the bedroom floor of my apartment next to my bed where my dongle for extra USB-3 ports was hanging off the bed. I have no relationship to this board, it's not ...
0
votes
0
answers
68
views
Why does it seem like the ideal photodiode model leads to a violation of conservation of energy?
Short version of my question:
Roughly speaking, the output power from a properly biased ideal photodiode feeding a resistor is quadratic with the optical input power, with seemingly no limit. So at ...
0
votes
0
answers
37
views
Finding pressure sensor specifications of portable integrity test device
I have a portable integrity test device (BEA Technologies – Italy), model Z02030300 (X-150-N.)
The pressure sensor inside is broken. I do not know the manufacturer of the sensor.
Does anyone know a ...
1
vote
1
answer
148
views
Justification for equivalent gate capacitance simplification in digital circuits
A MOSFET is, in reality, a four-terminal device with capacitances between each pair of terminals:
These capacitances are, of course, the standard MOSFET intrinsic and extrinsic differential ...
5
votes
4
answers
2k
views
Why do we usually operate well into strong inversion?
In textbooks like the venerable Gray and Hurst or in contexts like my introductory analog design class, it was always emphasized that with MOSFETs we always want our designs to obey some constraint ...
2
votes
0
answers
51
views
How to learn about memristors as a circuit designer? [closed]
I'm trying to learn about memristors to play with it in circuit design. I think it might be more intuitive to do tests and measurements rather than reading maths formulas. The problem is that I don't ...
0
votes
2
answers
631
views
ESP and a metal cover (but not on every devboad) cover under which it hides
This is regarding the metal cover on the ESP devboards, which covers, among others, the ESP itself, flash memory, etc.:
This topic has been discussed here before, and the reason for this cover is
...
0
votes
2
answers
426
views
Is there a surge suppressor or power strip that doesn't draw power when switched off? [closed]
I've read that leaving electronics plugged in but not being used still draws power. Is this true? But if it was turned off it would probably not draw as much power as it would be if it was turned on? ...
4
votes
3
answers
2k
views
What is this used for and what is it? (Wooden base, metal strip connecting two terminal blocks with finger nuts and small screws.)
This was handed to us and I have no idea what the device is, or what its usage is.
1
vote
1
answer
61
views
Will the saturation current through one of these NMOS circuits always be greater than the other?
Is there a definitive way to know for all cases if an NMOS would have a greater saturation current if a resistor R is connected to 1) the drain side or 2) the source side?
The assumption is that the ...
1
vote
0
answers
203
views
Remapping a PCI(e) device when another core is accessing the device
According to PCI(e) specs, is it undefined behavior to access a leaf device from a CPU core when another core is remapping that leaf device to another physical address (e.g. for MMIO on ARM)?
If not, ...
-3
votes
1
answer
133
views
How to make LEDs produce light like incandescent light? [closed]
LED light flickers around 100 Hz and is caused by rectifying AC power. How can LEDs be made to emit constant light that comes from an incandescent element which does not flicker?
0
votes
0
answers
69
views
Automated Hardware/Software Test
I am an Electrical Engineer and I don’t have a strong Software Engineering background.
My problem is: I need to test several Smart home devices. For example: a door that opens and closes (also 2 ...
1
vote
1
answer
106
views
Trouble with body effect physics
I’m struggling to understand why a negative voltage applied to the bulk contact of an n-type MOSFET increases the threshold voltage.
I read other similar questions and I get that the negative voltage ...
-1
votes
1
answer
92
views
What is this technological device?
Today at work, I came across this device. One of the black lids has the inscription PGEP79. A small amount of colorless liquid was contained inside the transparent casing. Overall, it looks like an ...
1
vote
1
answer
543
views
HAL USB device library transfer complete callback (USB MIDI adaption)
I have been able to implement Zac Rogers USB MIDI adaptation of the Cube MX USB device middleware:
https://github.com/zacrogers/blue_usb_midi
I can send USB midi messages on both F103 and F411. It ...
1
vote
1
answer
78
views
Reduce number of device power supplies
I have three 5 V DC, 1 ampere devices running from three separate standard manufacturers 240 V power supplies.
Can I connect the three devices in parallel to a single 5 V, 5 ampere power supply?
0
votes
1
answer
1k
views
MOS Capacitor band diagram question
In a MOS system, is the energy offset between metal/oxide or semiconductor/oxide always the same regardless of the gate voltage applied? In other words, are A and B in the diagram above always the ...
2
votes
2
answers
534
views
What are up-screened components?
What are up-screened components/devices in the frame of qualification of electronic components?
How is it done?
2
votes
2
answers
1k
views
Why does the majority carrier concentration near the junction not decrease under forward bias? (PN junction)
We see that the current due to the majority carrier decreases near the junction as shown above, which means the majority carrier concentration should also decrease since the diffusion current is given ...
0
votes
2
answers
84
views
Precisely determine the actual consumed watt of the device [closed]
What is the actual consumed watt of the device stated a value of input watt and a value of output watt which we often see it?
0
votes
2
answers
74
views
The definitive method to probe the device operating current
How can I measure the current a device consumes?
I tried one that has 1.5 V power supply requirement. I measured its resistance with a DMM from the power supply box (with the batteries removed) by ...
0
votes
2
answers
4k
views
Which alcohol is bad to use when cleaning computers?
I heard there are some alcohols that are prohibited to be used when cleaning a computer or an electric device.
Apart from beverages, which ones are these?
0
votes
1
answer
136
views
Do not connect Vdd and Vss with AD732x ADC?
According to the AD732x datasheets, especially the figure of "Equivalent Analog Input Circuit (Single-Ended)", do not connect Vdd and Vss should have no effects except on throughput rate (...
1
vote
1
answer
87
views
Feature 'logo/labels' on cases of self made devices
Not really an electronics question however has something to do with the tech you have used for your own projects. For example, on any consumer device with USB support, Bluetooth, HDMI 2.x etc there is ...
4
votes
2
answers
468
views
Single AA battery to mains power
I am trying to figure out how to run a device that requires 1 AA battery (1.5v?) Using a mains adapter.
All the adapters seem to be 3v minimum.
Can anyone help please?
Product details: https://www....
1
vote
0
answers
54
views
Data transmission through multiple IoT devices
We are implementing a device which will have multiple sensors inside multiple houses in our local area.
Each house will have 1 device fixed at a place and data will be transmitted to one central ...
0
votes
1
answer
4k
views
What is the effect of using wrong DC adapter to power on an electrical device?
Electrical devices powered by a DC adapter have specific in/out voltage/current values, so as an example what will happen if we used an adapter with 9v/1A output for a 5V/0.5A device?
Consider all ...
2
votes
1
answer
2k
views
Understanding XLR phantom power adaptor
It's a scheme for microphone adapter, from XLR to mini-jack, with the conversion of 48V phantom power to plug-in power 6.2V. Could you describe how the circuit works?
2
votes
2
answers
1k
views
When to consider Peak current/voltage vs. RMS current/voltage and vice versa
When manufacturers create power labels for AC electrical devices, what value to they use for the current and voltage? Do they use the RMS of the sine wave? Or do they use the peak of the sine wave? ...
0
votes
1
answer
92
views
The constant time value for an electronic device [closed]
i am working in a data science project that require certain information about electronic devices. So I know that for each electrical circuit there is a permanent regime and a transient regime and ...
0
votes
1
answer
51
views
Difference in electrotherapy Lifepak 12 [closed]
I'm a beginner medicine student and I've got a question out of curiosity, why in defibrillators lifepak 12 or other versions..paramedics or dictors set energy for defibrillation and cardioversion in ...
2
votes
1
answer
303
views
Vector monitor, purpose of a third "green gun" connection
I recently came into possession of a vector monitor, as shown below (Vector Monitor, Model: IO-1128, from Heathkit). Its got a red, blue and green "gun" connections. However, I am not sure ...
1
vote
1
answer
165
views
Create a synchronous network of 400 devices
I have around 400 devices that i want to address in a star topology. Each device controls a set of LED strips (27*12 resolution). The idea is display a video animation in a good frame per second rate (...
20
votes
2
answers
5k
views
What is the purpose of this device?
I found this device in my father's basement, but I can't figure out what this device is.
It has only 1 SCART connector, 1 power cable and only 1 button in front of it.
I think it may be some old video ...
0
votes
2
answers
78
views
Looking for the category of IC that would send a signal to all selected output pins simultaneously?
What would a multiplexer like device that allowed multiple outputs to be addressed simultaneously be called? - am looking to address multiple outputs in an array (many as possible - probably ganged) ...
0
votes
2
answers
107
views
AC to DC converter device (AC adapter) with adjustable output voltage and adjustable output current [closed]
Is there a device available in the market that can take an input AC from mains and convert it into DC and output it, the output current and voltage must be adjustable.
I know there are AC adapters ...
3
votes
1
answer
1k
views
Why is a DC to AC inverter called "inverter"?
A device to convert direct current to grid level alternating current seems to be called "inverter".
It's typically called like that when used in a solar power system.
Why is it called inverter? Does ...
0
votes
1
answer
139
views
How to turn a motor while obtaining the angle it turned?
I need a device where it can turn mechanically, while be able to measure the angle of which the motor turned.
One solution I thought about was to connect the motor with potentiometer.
However, is ...
0
votes
3
answers
249
views
What is this device mounted on my wall?
I just noticed this device in my apartment and am wondering if anyone with some electronics knowledge can tell me what it is.
22
votes
6
answers
10k
views
Can I disable a battery powered device by reversing half of its batteries?
When I have a device that is powered by two batteries, can I disable it by turning one battery around?
For illustration, the purpose is to leave batteries in the device for storage, but it does not ...
2
votes
1
answer
105
views
What device can switch ON and OFF different pads independently?
I am looking for a device, but I am not sure what I need: maybe you have ideas.
I have a power supply connected to 16 electrodes. What I need is a device (see picture) between the power supply and the ...
1
vote
2
answers
1k
views
SMD Device and manufacturer ID markings S2
I have a SMD device that I am am trying to identify.
Can anyone point me to a manufacturer? Probably a resistor but I am not sure.
Any help would be appreciated.
The scale bar in the picture is not ...
2
votes
1
answer
1k
views
General dimensions and recommendations for a USB dongle
I'm trying to create a device that connects via USB and sits in a users computers USB socket at all times, and I'm unsure of what the general dimension requirements will be.
Ideally, this device ...
4
votes
3
answers
2k
views
Why are "square law" devices important?
In the literature, I often see the notion of square law devices. Why are these devices important, to the extent that they have their own characterization as square law device?
In what context does ...
0
votes
1
answer
79
views
Connector identification (multipin connector for automotive touchscreen)
This connector is from a device connected to the touch screen in the car. This device is chinese, so I'm having trouble locating information about any part number or name.
The connector has 4 wires ...
0
votes
3
answers
1k
views
What exactly are low speed devices? [closed]
The definition of I2C is - "A multi-master multi-slave serial bus used for communication between low-speed devices".
However, I have been searching the web for a concrete explanation for this but ...
0
votes
1
answer
75
views
0
votes
2
answers
6k
views
The forward voltage Vf of a diode
I want to know about the forward voltage \$V_{f}\$ parameter of a diode device, given an I-V charateristic curve and in ambient temperature. What is the criteria to define the \$V_{f}\$ for any diode? ...
0
votes
1
answer
162
views
How can I power a device that requires 5-7V and 2.5-6 mA with what I have?
I have voltage pins on one device that outputs 6.23V DC and 70 mA DC. What type of circuit do I have to build that can power up another device that requires 5-7V DC and 2.5-6 mA DC using my 6.23 V ...