# All Questions

13,089 questions
533 views

### What is causing this long tail in the transient reponse?

I have a fifth order transfer function for which I designed a controller using pole-zero cancellation technique on a root locus. I am after <5% overshoot and <2s settling time. Currently, the ...
225 views

### Switch from JTAG to SWD with bitbang sequence on STM32F103VB

I am trying to switch from JTAG to SWD without any external devices. Why? Because I would like to use the SWO pin to send a stream of logging information to another device. To accomplish this ...
3k views

### Stability factors of a voltage divider bias circuit

I am trying to derive the stability factors of a voltage divider bias circuit. I could derive S,S', however, I'm facing some problem with the derivation of S''. Please help me in this regard. How to ...
131 views

### Microstrip transmission line impedance calculation

I'm attempting to calculate the necessary trace width of a PCB transmission line in order to have a characteristic impedance of 50ohm. However, different online calculators are giving me slightly ...
388 views

### LM386 guitar practice amp circuit not working, need help finding mistake

I'm very new to electronics and I built this guitar amp circuit on a breadboard: and it was working really nicely. Now I've decided to put the circuit on a universal PCB which I'll use in the actual ...
528 views

### Electric fly zapper - how is this safe?

My trusty electric fly-zapper broke, so I opened it up to have a look in case it was something simple. I have to say I was a little surprised by what I found inside: the capacitor reads 473K, meaning ...
87 views

67 views

### VHDL Procedure - Same variable for input/output parameter

I've written a component where I use the same variable for the input and output parameter of a procedure. A reduced example looks like this: ...
76 views

### Subthreshold Analog Accelerator - How is current derived through two sub-threshold transistors in series?

Was browsing the following paper: Fick, Laura, et al. "Analog in-memory subthreshold deep neural network accelerator." 2017 IEEE Custom Integrated Circuits Conference (CICC). IEEE, 2017. When I ran ...
177 views

### High-Level Synthesis (HLS) vs RTL for ASIC flow

I'd like to know when it's a good idea to use HLS over RTL (Verilog/VHDL) design if I'm targetting ASIC implementation? Can synthesis tools like Design Compiler convert HLS C/C++ into gate-level ...
91 views

### 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 ...
374 views

### 4 switch Buck-Boost, boost not reaching designed current

I am working on a power supply that regulates the voltage coming out of a 3S LiPo battery. The buck portion of the circuit works fine and outputs 5+A with acceptable ripple. The Boost portion instead ...
125 views

### Incrementing net name for group

I am wanting to make 50 copies of the block below, but I need incrementing numbers on each of the net labels (these will go to a connector). I do not want each block connected to the other blocks. It ...
148 views

### Help with deciding my layout for EMC tests and SI. Different alternatives

I am thinking of what way would be the best to layout my system in order for it to have the best SI and pass EMC tests. My system consists of two PCBs joint by a flat flex cable (up to 7cm) and these ...
3k views

### UART reception problem when SysTick Interrupt is enabled

I'm using a STM32F411RE-Nucleo board and generating a project with Cube MX for System Workbench. The problem is that HAL_UART_Receive function doesn't receive input ...
230 views

### Setting up T2080 to FPGA PCie DMA

I'm doing an FPGA design using a T2080 MPC interfacing to an Altera Cyclone V FPGA. The goal is to use my FPGA to pump 2 other FPGAs on the same board. I need to create a scheme that allows the ...
135 views

### imx6q sabre board microphone

I have been trying to record audio using the circuit below. It is different from the normal microphone circuit in that the MIC_IN and MICBIAS are separate paths. I tried to connect an electret ...
193 views

### Home made passive tablet pen

I have an old wacom tablet at home, its really big and I'd like to use it but I've lost the pen for it. It uses pens with passive LC circuitry. The board creats an EM-field (I can see it on my ...
113 views

### Testing strategies for testing a Scheduler

We have developed an in-house Scheduler which is based on Rate-monotonic scheduling. We have 6 tasks (5 actual tasks and 1 idle task). Our scheduler works on 1msec timer interrupt. Before sending it ...
3k views

### Dual active bridge converter

I'm having issues calculating the power losses associated with the operation of a bidirectional isolated Dual Active Bridge DC/DC converter. The converter is controlled using Phase Shift Modulation (...
75 views

### Is this symbol standardised?

Sometimes there are these two half-arrow symbols on PCBs and on enclosures. See the images, for examples. Those symbols are often placed near the screws, that are to be unscrewed upon disassembly. ...
45 views

### Frequency Divider Analog Circuit issue

I am trying to implement a divide-by-two circuit quoted from the book "Low power CMOS circuits : technology logic design and CAD tools" by Christian Piguet Could anyone advise about the spice error "...
68 views

### Inrush Current problem?

I have a 360W 36V Switch Mode PSU which I am using in a garden lighting system I have designed. I'm in the UK so it's running off 240V therefore can supply about 10A. Each section of the ...
40 views

### Abstract signal and noise model for a logarithmic image sensor

A conventional grayscale image sensor pixel can be modeled as a "light bucket." Photons arrive on the sensor pixel for a fixed exposure time. The light bucket fills up with photo-electrons linearly ...
65 views

### What is the difference between input and output offset voltage for an opamp?

Looking at many OpAmp (and InAmp) datasheets, I find the info either confusing or lacking. For example, in one datasheet they just call something Offset Voltage ...
99 views

Description of the situation I am trying to get an analog vibration sensor signal to a Raspberry Pi 3 B+. To convert the analog signal to digital values, I'm using Waveshare High-Precision AD/DA ...
65 views

### Switching regulator not suppressing variance in input?

I am having a little problem with my switching regulator, based on a AP65211A and here is my schematic: Parts: ...
30 views

### MOSFET pinchoff reduce current

I understand that in an n channel MOSFET as Vgs increases, electrons are attracted towards the gate forming an n channel. These electrons are responsible for the conduction of the MOSFET. As Vds ...
35 views

### 7030 SMD LED pad configuration

I have not done a lot of work with SMD LEDs and have a question about the pad layout. I have done quite a bit of research and haven't found much helpful info yet. I am working with 7030 SMD LEDs ...
92 views

### Find transfer function and step function for this circuit

Can someone help me to find the transfer function of this circuit (i want to have the tension through the capacitor I think) and the step response in order to get the voltage in the function of the ...
97 views

### Weird problem on STM32 ADC with Interleaved Mode

I am sampling a signal on the STM32F3 Discovery board (stm32f303vct6) with two ADCs working in interleaved mode. It works great with a 200kHz 1V sine wave. But when I apply 10kHz 100mV sine wave, I ...
43 views

### Advice for a Solar Charger and Battery Project

I am a high school robotics teacher (no formal engineering training) and I am taking a group of students to Kenya this summer to work with high school students there. The organization we are ...
55 views

### Detrimental impact of magnetic field on PCB and battery?

We are developing a small consumer electronics product consisting of a small 4-layer PCB along with a few PDM microphones and BLE chip/ an antenna, as well as a LiPo battery. We are locating a small ...
82 views

### Orientation of “bipolar” capacitors on PCB

I've come across a video on a popular and well-respected electronics channel on Youtube where they say that even bipolar capacitors have a preferred orientation in a circuit that minimizes hum and ...
58 views

### Power use question for a trail camera

I am trying to calculate how long that a trail camera can be deployed before the batteries run out. The trail camera in question is a Reconyx HyperFire 2. Here is a useful review of the trail camera ...
46 views

### Microphonic SAW transmitter?

I built this very simple SAW transmitter, with a simple "spring" antenna for the right frequency. To test it, I tuned a portable receiver to around 433.92Mhz and fine tuned it until I heard silence. ...
88 views

### How to distribuite high current in multilayer PCBs

I'm designing a 150Amp controlled rectifier and I'd like to know how to distribute the current using a multilayer design. Currently, I have a 4 layer design containing: Top Layer: 6oz, Vdc+ and Vdc-...
55 views

### Alternate uses for Gate Driver - Driving a Load without External IGBT or FET

What issues would one encounter by using a gate driver IC to directly drive a load instead of using it to drive transistors? For consideration would be the very affordable Infineon 2EDN752x series ...
62 views

### Can I extrapolate battery power by a brief observation?

Part of the research we are conducting requires us to estimate how detrimental our proposed algorithm to the battery life of the wearables. To do so, I opted to simply charge the wearable to 100% and ...
87 views

### Why are project files in Altium modified every time they are opened? Is there a way to prevent this?

I use Altium Designer 18. When I open a project file (.PrjPCB), the asterisk ("*") appears next to the project name indicating that the project has been modified, but I haven't actually made any ...
82 views

### Modeling scalar control of PMSM

I have met with a scalar control algorithm for a permanent magnet synchronous motor. I haven´t heard about it before so I decided to develop a dynamic model to further analyze this control algorithm. ...
76 views

### How to select a diode for baker clamp?

What are the requirements when selecting a diode for baker clamp circuit? 1- for example, How the reverse leaking current of the diode affects the circuit? can a diode with relatively high reverse ...
56 views

### System of multiple conductors: image method

The problem statement, all variables and given/known data The following figure represents the traversal cut of a system with two cylindrical equal conductors of radius r0 length l at a distance d ...