Questions tagged [pcb]
PCB is the acronym to Printed Circuit Board. A PCB is a carrier for the circuit's components and their electrical connections.
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Proper Way of Validating Hot Spots on Xcede Connector and PCB area
I want to verify if this method of validating hot spots on connectors and PCB areas is proper:
Drive circuit to max current
Use a thermal camera to find hot spots
Is this actually the best way of ...
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12V 1.5A through a switch [closed]
I am making a really simple electrical circuit for a school project. This is the first time I've done this.
The buttons I have are rated for 50mA@24V but I need a power supply of 12V 1.5A to use ...
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Coilgun bus design
I'm a middle schooler designing a 12 stage coilgun. There are separate pcbs for each stage, and each pcb has an analog output that goes to the arduino, and a digital input for the arduino to send a ...
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What's missing here? (DB1) LED bar [closed]
Can anyone help me?
This is a visibly tampered LED strip and it's missing this component DB1, which I think is a diode but I don't know exactly what it is.
The LED strip is powered with 220v.
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Bridge Rectifier Problem or something else?
I am designing a 30V 5A power supply and after simulations working fine I decided to make it on actual hardware. But during the first run, something shorted and the power supply didn't even turn on.
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PCB Design Review Request
I am designing a MIDI controller board. It's my first board ever and I was just wondering if people could check a part of my design for potential problems and shortcomings.
Each section is controlled ...
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PCB short circuit without any component
I'm working on a PCB and I've ordered my first prototype. However, there are some problems. I soldered the decoupling capacitors on the power line and applied a 3.6V voltage to the circuit from the ...
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ESP32 with CP2102 - PC does not recognize the controller
The controller that I made does not show up in the device manager when connected to PC. I checked the drivers and the problem is not there. I already found (and corrected on the schematic) one mistake ...
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Could isopropyl damage a PCB?
I cleaned a PCB with isopropyl alcohol, 75%. When I turned it on, something strange happened. The microcontroller GPIOs that drive the LEDs started to behave like they have relatively low resistance, ...
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Identify number of strings in Philips 14.5W LED PCB
Is it possible by just looking at the attached image whether the LEDs are in a single series circuit, or whether they're configured in series/parallel? The image is not great but I tried to highlight ...
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PCB panel design
I am designing a 4-Layer 0.5mm thickness PCB.
The outline is rather small which introduces some problems with panelizing the PCB. As I am a novice regarding these topics I would like to ask for help.
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PCB 0402/TQFN pad design
I am currently designing a product which uses 0402 passives and other fine-pitch parts. As the PCB-space required is a major design goal I want to reduce the footprints. High production yield is also ...
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How to implement a Bookbinder PCB design in Altium
I am planning to design a bookbinder with airgap rigid flex PCB using Altium.
Based on guidelines from Altium, and various other sources, it is important to have "staggered lengths", to ...
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What momentary switch should I use?
I want a switch that has 2 distinct non-momentary states (say UP and Down) and a momentary state. In both states (...
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Connector identification for Avermedia C875
I have an AverMedia C875 device, I would like to capture an analog output of my VCR with it. The device has a specific connector for such purposes, but I sadly don't have the dongle that originally ...
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Can I replace a PWM IC on a PCB with another PWM IC from the same vendor but having a slightly different part number? [closed]
The PCM is of a power supply unit for a speaker and it has this PWM IC (OB2362). I am not able to find an exact replacement to that chip but found a close match (not sure though): the OB2263. It has ...
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Short inside 2 layer ECU PCB
I am repairing a Delphi MT34 ECU, and after further investigation I came to a problem I couldn't understand or fix. After removing the triple regulator IC and all components in the track, the short is ...
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Is it ok to short data lines of USB-C
USB type C has 2x DP+ and DP- on the connector. When laying out the PCB, is it ok to short each DP+ and DP- together?
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How to remove tenting from specific vias?
I defined a SolderMaskExpansion rule in Altium and with that way all vias are tented. But I want to remove tenting for some of the vias. I mean, I want some vias to be tented and some vias to be non-...
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PCB Routing Considerations for multiple USB Port Types for USB 1.1 Full Speed
I wanted to make a device that has a USB A and a USB C connector on apposing sides of the PCB, similar to the attached image. These USB connectors would be connected to the same USB port, the MCU I ...
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How does current flow in multiple vias?
How does current travel in multiple vias from one layer to other?
For example, we connect four vias, each of which has a limit of 1.3A each from power plane to sink device. If the sink draws 4A of ...
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PCB etching went wrong or what?
I was trying to etch a PCB of 12x23 cm using FeCl3 powder. Below are the pictures of the process:
Before dipping into etching solution (some tracks were corrected using permanent marker):
After ...
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Using other boards than PCB for commercial electronics products
If one solders entire circuit components (such as resistors, caps, opamps) a board as in the following photo:
Is this type of interfacing legal for commercial products? I'm wondering if there is any ...
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Circuit appeared to work for a few minutes at first, then poof! Can you help me figure it out? Diagram included
thank you for taking the time.
I have this PoE design that takes 48V and knocks it down to 5V for powering generic USB devices.
I received some new boards and when testing them, discovered they ...
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How would one build a circuit board without hiring a manufacturer?
Assuming one had access to old CPUs, ram, hard drives, and mainboards with I/O connections and BIOS chips and other chips in them.
I know the basics of the gates to make CPUs and RAM, and I know it's ...
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Eagle I can not change the isolete value of bottom Ground polygon
well this is my PCB design with Eagle Autodesk. Ground polygon looks perfect with Isolate value 0.8128 [mm] on Top.
but this value can not effect bottom polygon Why? How can apply 0.8128 isolate ...
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Different capacitors between VCC and ground required for different sensors and components [duplicate]
I am designing a custom board with a ATmega16u2. In the specifications of the linear voltage regulator, a 10uF capacitor is required between the regulated voltage and ground. A 1uF is required between ...
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Resistance measured individually vs measured on PCB
I always wanted to ask this question.
Suppose I have a 1kohm resistor. I measure its resistance by connection a multimeter to both of its terminals (when it is not connected to any part of a circuit.) ...
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Where can I find large thru-hole heatsinks like this? [closed]
I'm doing a project with an OPA541 amplifier, and I need to find a heatsink similar to the one in the pictures:
But I only found small ones with a screw hole and legs for soldering, none of the large ...
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Is voltage important for calculating PCB trace width? If not, why?
As per the IPC 2221A the formula for calculating PCB trace width follow the process given below;
First, the area is calculated:
Area[mils²] = (Current[Amps]/(k*(Temp_Rise[°C])b))^(1/c)
Then, the width ...
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Add only a subset of components to PCB in KiCad
In the KiCad PCB Editor, when I click "Update PCB with changes made to schematic", all missing components are added to the PCB. How can I add only a specific selection of components? (For ...
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Using High Power Relays to Actuate an AC Motor
I want to remove the need for contactors in a motor application. Currently we are using a 1.5HP (1.1KW) motor and actuating it via a contactor.
I have a PCB I am designing and want to use the ...
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How to deal with one clock input at the IC when most crystals and oscillators have two pins?
I am having trouble in figuring out how to deal with an IC that only has a single input for the sleep clock. Does one pin of the clock go into the IC and the other to ground, or does configuration ...
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Class AB RF Amplifier with only one active device
I'm designing an amplifier for the 420-440MHz band. I'm looking at using the following part from Ampleon: BLP15H9S100. I'm new to doing RF amplifier work and I've been going through the design process ...
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How to fix the keyless key (replace the antenna) of Mistubishi Outlander?
Background story:
I had a keyless keyfob for my Outlander, and lost it.
I went to the service and they configured a new key for me.
The serviceman told me that many times when the key falls the ...
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Is 0.01" dimensional tolerance the industry standard for class II and class III circuit boards?
Or does it vary? This is a reference request for ridged PCB thickness. Email from a US manufacture:
This is from the board house.
Your customer has a profile (routed pcb outline) tolerance of +/-
0....
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How can I adjust the imported 3d body in Altium designer?
I've downloaded and imported the following SMPS transformer 3d model into Altium designer but it doesn't fit my footprint how can I adjust it by changing scales and moving pins?
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Bandpass filter doesn't work when implementing PCB
I have been trying to make a 5th-order Chebyshev filter going from 500 MHz - 570 MHz and a 3rd-order Chebyshev filter going from 500 MHz - 540 MHz. This is my first time making a filter into a PCB.
No ...
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PCB and breadboard parasitic capacitance
I am getting different bandwidth measurements from my breadboard and PCB (for the same circuit with exact same component values). The cut-off frequency I measure on the breadboard is slightly higher ...
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Kelvin connections in PCB
in the following webinar from youtube, a recommendation is presented about the kelvin connection at the 41st minute of the video. but I couldn't get it. (second language)
https://www.youtube.com/watch?...
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How to unplug these connectors on 80's amp/receiver
I'm trying to unplug these connectors to get access to the lcd display.
Do I need a special tool? I tried but to no avail. The little ones seem fragile. What is the name of these connectors?
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Plane layer thermal relief rotation with Altium?
It is straightforward to configure horizontal/vertical thermal relief connections with polygons, but with Plane layers, it seems the option isn't available. The result is not very professional (see ...
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How to use plane layers with Altium and Eurocircuits?
I don't quite understand Plane layers in Altium. For one particular project, we made a decision to use Plane layers instead of signal layers.
When exporting the production files (Gerbers) and ...
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Is there any difference between Silicone and RTV
I've used silicone RTV that's intended for use on PCBs and have also used 100% silicone purchased from the hardware store to use on PCBs. I was not able to tell a difference between the two. ...
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Antenna feed trace keep it short or long?
I am designing a GPS module but am quite new to RF design. I have seen a number of people say to keep your antenna feed line as short as possible. But in the design guide of the GPS module I am using, ...
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Magnetic field shielding for electronics?
I am looking at an issue where a PCB design that is powered by a couple of CR2032 batteries will shut off all of a sudden in the presence of strong magnetic fields (around 15-40mT). However, when the ...
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What could the component be if the diode test result shows finite voltages for both orientations?
I was trying to identify a 2 terminal component using the diode test in DMM- It measured 0.420V in one direction and 1.88V in other direction.
I am not sure what this component could be. For other ...
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High Voltage & Low Voltage PCB Design
I am trying to make a PCB that acts as a "Raspberry PI HAT" and allows me to connect the raspberry to different sensors. Specifically, I'm having difficulties in defining the design rules ...
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Greener way to design a PCB
Lets say we are designing a very simple PCB and there is a layer(s) where not much is going on, from an environmental perspective alone would it be better to leave the layer with a large ground copper ...
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What is the use of this capacitor compared to the other near it?
It is a lock PCB circuit and I can't understand why it's parallel to the 12 V and ground (the capacitor I circled), but the other capacitor (C539) is like a maintaining contact for 24 V.
