Unanswered Questions
21,291 questions with no answers
11
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Estimate base-spreading resistance from Gummel-Poon model
I'm attempting to calculate the base-spreading resistance of BJTs from manufacturer-provided SPICE models, which use the Gummel-Poon model. This Agilent publication (Internet Archive link here, if ...
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10
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x86 Motherboard Bring Up - Intel Tiger Lake UP3 CPU
For those who has experience with Intel x86 motherboard design and bring up.
I'm in the middle of motherboard bring-up that has Intel Tiger Lake UP3 CPU.
Seems like I had a good run so far at power-up ...
- 1,107
7
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292
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Extremely long net in Xilinx synthesized design labeled "async_path". What's it for?
I used Vivado to synthesize a small design for the Xilinx xc7k-160t-1. The design includes a fifo instantiated with Vivado's XPM macros which crosses clock domains from 100.8MHz to 200MHz.
When I ...
- 1,467
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Frequency locking for averaging resampling
Background
I've done a long one-shot measurement of a periodic signal by an oscilloscope. Thus, I've captured around 250 periods of a signal. The signal itself is a pseudo-random binary sequence at ...
- 711
6
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959
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Understanding EGSM-900 (LTE 8 band) electromagnetic spectrum
I am trying to fully understand the physical layer of the GSM standard. For doing that I am looking at the E-GSM-900 band (mostly used in Europe). In my country these frequencies has been assigned to ...
- 185
5
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194
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Why does output of this reverse bias noise source not have normal distribution?
I am trying to build a noise source based on reverse biased PN junction (i am trying to replicate this project https://altusmetrum.org/ChaosKey/ ). At this point i tried multiple iterations but so far ...
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5
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772
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How to match an edge launch SMA connector to a pcb with coplanar waveguide with ground?
I'm trying to develop a pcb that is capable of handling signals over 6GHz and created a test board to see how the pcb and connectors perform. The pcb is a relatively low-cost 4-layer FR-4 TG155 board ...
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5
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Bidirectional flyback converter design
I see a fair amount of questions on here about designing flyback converters, but I don't see any about designing a bidirectional DC/DC flyback converter, such that either side can be the primary and ...
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STM32 - I²C Slave HAL Callback ACK
Objective: implement a single byte I²C slave on STM32.
Materials: STM32L452RE Nucleo-64 board, HAL Library, CH341 USB-I²C adapter(1), Artix Linux with Runit, Rhode & Schwarz RTB2004 oscilloscope
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5
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310
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Cannot find what causes faults on DRV8353RH
I keep getting faults on a a new batch of ESC boards based on the TI DRV8353RH & Infineon IPT020N10N3ATMA1. Please consider:
When starting a motor at 48V - 56V the DRV asserts a fault after ...
- 111
5
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245
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Invisible magic components that spoil the Eagle preview
You know, after the eagle board design is finished, you can see the card on the preview screen.
I'll show you two examples. There is no problem with one. The card is centered on the preview screen.
...
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5
votes
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answers
451
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Detection of CT secondary subsidence current
In utility power system protection we have a protection function called "breaker failure" protection. This protection is used to take appropriate action if/when a circuit breaker fails to ...
- 3,720
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785
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Drift with Madgwick algorithm with fast movements
I am trying to correctly track orientation of a sensor with accelerometer and gyroscope using the open source Madgwick algorithm. The algorithm returns quaternions which represent the rotation between ...
- 185k
5
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136
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What complications arise when designing a USB device sharing switch?
I wish to design and build a USB switch capable of transferring one USB keyboard between one of two computers. I wish to automate the process of unplugging the device from host A and plugging it ...
- 155k
5
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Potential issues with mounting tiny PCB directly to piezo transducer?
I am designing a very small signal conditioning daughterboard with the intent of mounting it directly underneath a cylindrical piezoelectric force device/"sensor" to rectify and filter the ...
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