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.
6,435 questions
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Panel for flexible PCBs
I would like to know what parameters a panel for flexible PCBs should have. Can I use V-cuts or milling? What are the methods of depanelization? Should any part of the panel be rigid? Does anyone have ...
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Do I need to add capacitors at each VDD VSS port of a MCU chip?
I am learning about the STM32F103CBT6 microcontroller and would like to design a simple PCB. I noticed that the pinout diagram shows four pairs of 'VDD' and 'VSS' ports on the chip. Given the ...
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MP2315s buck converter not working
I made a buck converter using MP2315s, and when I tested the final product it didn't work like it should be dropping 12v to 5v. Tested and no output
I input a 12v to the input of the PCB, and the ...
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Do I need resistors in my circuit?
A little backstory. This is my first time creating a PCB with SMD high power LEDs. Or rather, first time to create anything on a PCB. One of my old LED Lights used for reef aquariums was not working ...
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Requesting Feedback on My First PCB Design: Improvements, Grave Mistakes, and Next Steps
I'm a beginner in PCB design and recently created my first design. Since I am a skydiver I thought a simple device for detecting altitude would be a nice point to start and fun to test. I would ...
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What value should I use for the Impedance trace to copper?
I am designing a PCB with a USB Type-C connector. The USB requires a differential pair for high-speed data signals, and I need to calculate the trace width for these differential pair traces. To do ...
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Why is this not a net antennae? (Altium Designer)
Why would this not be flagged as a net antennae in Altium Designer (25)?
This is a GND pour covering all of the bottom layer in my PCB design, and the TH vias (mostly meant to conduct between layers 1 ...
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How can I make a PCB for this sensor? [closed]
I tried to use a breadboard and resistors to use this sensor before and failed miserably. I want a PCB instead. Something guaranteed to work. What company can make one for me?
https://mm.digikey.com/...
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Is my NEO M8N GPS design true?
I have always used GPS breakout cards until now. Now I want to use the same modules in another card that I have produced more professionally. I have obtained such a drawing with the drawings I found ...
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Custom ESP32-S3 board usb disconnect and reconnect every second [closed]
I connect esp32 s3 wroom board to pc windows 10. I hear usb connect noise than 1 or 2 seconds later it disconnects this repeats so it is constantly connecting and disconnecting. I held reset button ...
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Gas water heater: power connection to a thermostat
I purchased a Netatmo smart thermostat, which is supposed to be compatible with my Saunier Duval Thema NOx F25 domestic gas water heater. According to the heater's manual, a connector labeled X16 ...
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PCB routing: how to connect the ground?
I want to create a PCB schematic of a very basic AC/DC converter and I'm a total newbie.
What's the best way to connect ground pins? Transformer is through-hole. Do I have to pour in a second layer ...
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How do I create the switching signals for my DAB converter?
I am currently designing a DAB converter (work in progress) and I'd like to know if there is an easier method for driving the switching signals than the method I have below using a TC4425AVPA to ...
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Full Bridge Rectifier - Output Voltage Saturation
I am putting together a full bridge rectifier, see schematics. The load is connected to V+ and V-. Capacitors as low ESR and with respect to the standard formula.
simulate this circuit – ...
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ADS1263 + ESP32-S3 PCB schematic
I am designing a four layer PCB with a TI 32-bit ADC (ADS1263) and an ESP32-S3-MINI-1U-N8. The aim is to use this board to read the output of an OPA197, which act as a buffer to a sensing resistor as ...
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Simplest way to design a PCB to mass program 10 ESP32's over a single high-speed USB-C port
I am trying to flash up to 10 ESP32's with firmware over USB (similar to the ESP32 Programming Tool that has a USB to UART converter), but I am trying to do it from a single high-speed USB-C line, and ...
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Doubts about the format of 4-layer PCB
I am currently working on improving and correcting the hardware design of two of my company's products. One is a small board measuring 55.499 x 31.369 mm, based on an ESP32-PICO D4() and an STM32G070, ...
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Meander antenna in the corner of PCB
Can anybody think of a reason why I should not put an antenna in the corner of the PCB like this:
It is useful in my design because the board is quite big, and i cannot afford removing copper along ...
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Are the 2 power sources connected inside this IC?
If I connect a USB power source to the IN1, OV1, and PR1 pins of the TPS2121, and another power source with a large capacitance (e.g., 200 µF, exceeding the 10 µF limit imposed by USB specifications) ...
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How to match 50 ohm impedance on 2 layer PCB?
I'm trying to make a 2-layer board with 50 Ω impedance from JLCPCB. The picture above is a 2-layer stack up provided by JLCPCB.
And the width calculated based on this is about 2.7 mm.
Other ...
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What is the total capacitance on the VBUS line in this case?
I am working on a PCB that is supposed to be powered either by an USB Type-C or by a 3 cell LiPo battery, so in this scope I decided to use the TPS2121 power mux. The problem is I don't understand how ...
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Is this a good design for having 2 power inputs for a PCB?
I’m designing a PCB powered by a 3-cell LiPo battery. The battery provides +12V, which is stepped down to +5V using a buck converter. From there, the +5V is further stepped down to +3.3V using an LDO ...
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Best way to design a PCB for frequent component switching?
I'm getting a PCB made with an OpAmp circuit on it that will need some tuning. We aren't sure what resistance and capacitance values we'll need to use for the integrator circuit. These will need to be ...
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LM386 Amplifier Circuit does not produce sound
I'm not an electrical engineer, but i love to learn about electronics.
So i try to make LM386 amplifier circuit to a PCB which can be connected to smartphones, mp3 players or other devices that have a ...
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Is this a good design for connecting 2 power sources to the PCB?
I’m designing a PCB that is powered by a 3-cell LiPo battery. The battery’s +12V output is stepped down to +5V using an LM2596S-5 switching regulator, and then further stepped down to +3.3V with an ...
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Understand nominal current of Phoenix Contact PCB headers
The PCB header MSTBVA 2,5 HC/ 2-G-5,08 (1924305) from Phoenix Contact is listed with a nominal current of 16A.
Does this mean that I can load each pin with 16 A simultaneously or only both in total?
I ...
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Is this a good schematic and did I choose the correct components?
I am using the LP38693SD-3.3/NOPB (datasheet) power converter to step down +5V to +3.3V. I used the WEBENCH power designer tool from TI for the schematic and I chose the input and output capacitors ...
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Can I trust Altium Designer Impedance Calculator over my PCB Fab?
Hello hardware people,
I'm working on 6-layer boards with impedance control.
I usually follow the standard stackup suggested by my PCB fabricator.
I am creating impedance traces for LVDS of 100 Ohm. ...
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Best location for a heat sink - On top of SMD package IC or bottom of PCB
I have a circuit board with several MOSFETs in TO252 and TO263 packages as well as other IC with exposed pads on the bottom.
I need to cool these parts and have 2 options:
Glue a heat sink directly ...
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Why this PMIC has Via between capacitor and PMIC pins?
Why this PMIC has Via between capacitor and PMIC pins?
Does it break the flow?
Is this good layout practices If yes then how?
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How do I mount multiple circuit boards in a project box? [duplicate]
What's the best way to mount multiple, different sized, circuit boards in a project box? For example, I have a new project that requires a relay module board, a DFPlayer Mini MP3 player board, a Jemmy ...
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Need for cleaning solder residue for 7mm spacing due to breakdown voltage
I've designed a board that I ordered from JLCPCB. I have traces with 7 mm lowest spacing between them and with voltage of at most 400V AC, 525V peak between them.
The traces couldn't be wider due to ...
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Is there a way to search like CTRL+F in Gerbers or a PCB picture to find a specific part?
Is there any way to search for a component with the new AI advancement in image text search?
When I am looking for a part, I typically search through the silkscreen or the PCB itself, until I find it. ...
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Do I have to bother with isolation?
I am currently designing a device which is intended to communicate with different devices over RS232. The communication targets are mainly network switches from different manufacturers. The distance ...
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Does this PCB have a specific name?
This is used as a giant button (8x8in). There is a copper sheet suspended overtop. The sheet then shorts the tracks together to indicate an action.
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Connect ring terminal to PCB (low profile)
I have a BLDC motor control PCB (custom board - 15 A peak). The requirements for that board is to have low profile (max around 15-20 mm)
The chosen BLDC come with ring terminal crimp that need to be ...
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How to calculate PCB area size for Triac
I am using a BTA40-600B in a RD91 package to control an resistive load. My max current thru the triac will be 12 A - 120 V AC. According to the data sheet, P(W) for 12 A is 12 W. Junction to case is ....
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Did I calculate correctly the ESR of the MLCC?
I am using the LP38693SD-3.3/NOPB linear regulator from TI. In the datasheet of the IC under 9.2 Typical Application>Output Capacitor it says I need a ceramic capacitor with an ESR between 5mOhms ...
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Integrating USB and TPS62933 Buck Converter for ESP32
I'm working on a schematic for an ESP32 project, using a 6V battery pack as the primary source and the TPS62933 buck converter to step down to 3.3V. I’d also like to add a USB-B Micro input (5V) to ...
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Mod Projector to Power On when Plugged In [closed]
I have a projector (it's a VOPLLS M10) that’s hooked up to a HomeKit enabled smart outlet, but the projector doesn’t power on when “plugged in” / smart outlet is turned on.
The projector only turns on ...
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Convert 6V to 3.3V Battery Schematic (Review and validation)
I’ve been working on a PCB design for a power circuitry prototype using a 4AA battery pack. I’m using the TPS62933 buck converter to step down from 6V to 3.3V and would like to confirm if my schematic ...
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Could I run into problems by connecting +VBUS and +5V directly without any protection even thought I intend on using only one power source at a time?
In my schematic I have 2 power sources, a 3 cell LiPo battery and +5V from the USB VBUS. The +12V from the LiBo battery are stepped down to +5V using a buck converter and from there the +5V are again ...
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What is a "CFG" reference designator and these components with "O" label?
I have a PCB with burnt component, which is numbered as CFGx and there is an "O" on the component:
I looked up but was not able to find anything. It might be configuration related and not ...
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Proper connection of different ground zones / Isolation
I am currently working on a board that has some different IO options such as Ethernet with discrete magnetics, RS232 and USB2.0.
I do struggle with connecting the different ground regions properly to ...
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Need help identifying a PCB-mountable version of this connector
I have searched the internet trying to even identify this. Does anyone know what it is? This is on the end of a cable but ultimately I'd like to plug a circuit board in where this goes, so a thru-hole ...
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Probing many test points on PCBs
I often have to trouble shoot one-off instruments. At the moment if I can't get a hook probe onto a pin I will scratch off some solder resist or use a pad to solder a flying wire to the board.
I'd ...
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Help with IP2368 for 20V PD Output – Not Working as Expected
I am using the IP2368 IC to achieve a 20V output for USB Power Delivery, following the guidelines in the datasheet. However, I am experiencing issues, and it’s not functioning as expected.
Here are ...
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Another boring relay board with ESP32
After years of breadbord and relay boards, I would like to try to build a my own relay board, the relay side schema is the follow:
Figure 1.
I went for the 2N2222 but the BC337 is a good candidate ...
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What is this IC? KA=7F 9A1
I am trying to find what IC is this and its datasheet but I can't find it anywhere.
KA=7F 9A1
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What options are there to reattach/replace this pad?
This pad came off while I was desoldering a PLCC chip. I still have the pad.
As you can see I was able to scrape away to expose the via the pad was connected to and get a blob of solder onto it. I ...
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