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.
6,187
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What exactly makes the SET_ADDRESS command fail in my situation?
TLDR: Can USB packets be transmitted between host and device, even if a possible hardware problem exists as evidenced by a USB error -71?
I am working on a custom ...
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Help testing pcb [closed]
8’ led shop lights they’re going out 1 by 1 and half of the light stops working then the other half isn’t far behind…..can the driver be tested to determine which part is failing I suspect that all ...
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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 ...
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Trace between RFM95 module and U.FL connector
I want to connect a SMD U.FL connector with RFM95.How can I calculate the trace width of the signal and ground lines between the RFM95 and the U.FL connector.?
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Easiest way to power a 3.3V microcontroller from a 9V input?
I know there are discussions about this topic on this forum, and reading them has given me some good suggestions. Essentially, I have a PCB that is powered by a single 9V battery. I also need to use ...
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VDD and VSS pins shorted together
I have a PIC18F2420 MCU taken out of a PCB. There is a short between pins 8,19 and 20 which are VSS,VSS and VDD respectively.
Has this MCU completely failed?
One thing I have noticed when the MCU was ...
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1
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micro usb is not giving 5v but instead vbus is giving 0.45v
I just got my first 4 layer newly assembled board from PCBway.
When USB cable is connected, the board is not powering on.
When I checked the vbus it's showing 0.45v. After this I checked the MOSFET q1 ...
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Who produces this board and where can I find a circuit diagram/ data sheet?
I have this circuit board from a rear bicycle light. I want to know who produces them so I can find a circuit diagram and data sheet.
It has a logo on it and the text: RCY-1 94V-0 STEADY REAR V01
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Using ON-ON switch instead of ON-OFF switch?
I need to order a switch to turn ON or OFF a circuit, which would be mounted on a PCB after the power supply. This switch has to meet various specifications (through hole right angle, i>1A, v>...
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Implementing Swap in PCB Project Using Altium
I’m currently adapting an electronic project based on a schematic that was provided to me. Unfortunately, I cannot share parts of the schematic due to confidentiality reasons. However, I have created ...
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power input terminals on PCB shows zero resistance [closed]
I am newbie in electronics and struggling to find what is wrong with PCB I have for desk.
I have the height adjustable electric desk, and suddenly the height adjustment stopped working. Whenever I was ...
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Passivate one channel on a dual band chip antenna 2.4GHz / 5GHz
I'm making a dual band chip antenna design. For 2.4 GHz and 5 GHz
The antenna is this one: ANT162442DT-2001A2 from TDK
My problem: I'm using an esp32-c3 with 2.4GHz support... no 5GHz support... so I ...
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Is this layout for the power section alright?
I’m working with two buck converters (LMR51430XFDDCR) and am currently designing their layout. I’m unsure if there are any potential issues with my current design. I am aiming for a PCB as small as ...
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Soldering RG179 coaxial cable directly to PCB
I'm building a very low-cost bidirectional SDI-3G to fiber converter. I am in the process of selecting a connector for the SDI part. The issue is that I can't really find one that won't explode the ...
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Where should the Cff cap be placed in this design?
I used the power design tool from TI for the LMR51430XF buck converter (the details are in the first screenshot). In the design, I have a Cff CAP that doesn't appear anywhere in the datasheet of the ...
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LPDDR4 layout, should we avoid having signals in same byte group on different layers?
Is it a bad idea to route intra byte DQx on different layers?
I am trying to interface AM6442 to LPDDR4 16bit. I have followed every constraint in TI's DDR layout guidelines to the letter, ...
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Automatic Switchover Between Two Supplies
I am using two power sources for my PCB (USB 5 V, power supply terminal 12-24 V). I want to power the board via USB if the power supply is not connected.
while I was looking for a solution, I came ...
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Parallel IR recievers facing opposite directions? [closed]
I have a circuit with an IR receiver, but I also want to be able to point the remote at the back of the unit, can I simply wire another on the back of the PCB in parallel with the factory one?
Only ...
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3
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Is there a difference between these two layouts?
I am using an SG90 servo motor with a 100nF(C16) decoupling capacitor and a 100µF(C20) bulk capacitor at its power pins. I'm wondering if there's a difference between these two layouts or if both ...
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Which Arduino pin is giving gnd to the bus rail on a PCB?
I'm using a protoshield v2 for my Arduino Uno R3 project and I'm a little confused on how the bus rails works.
So I understand that the 5V pin from the Arduino is giving 5V to the 5V bus rail on the ...
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VNQ9080 input pull-downs
I'm using the VNQ9080 in a design and am undecided about adding pull-downs to the inputs. The inputs are controlled from a SX1509 I2C I/O expander which has the pins on HI-Z by default. I want to make ...
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Personal Safety Alarm pcb board (via Piezo Buzzer) Question - missing inductor part
I’m working on a personal project, and I could really use some help. I’m not an electrical engineer, so I apologize in advance if this is a basic question, but I’m a bit stuck.
I paid someone to ...
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Choice of oscillator for microcontroller
I'm using STM32F103C8 and I read Oscillator Design guide and one of the part numbers of recommended 8 MHz crystals is this one:
------------------------------------------------------------- 1 ------...
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When using a servo with STM32F405RGT6 do I need to connect any CAP near the servo pins?
I am using a 9g servo motor and have connected two 100nF ceramic capacitors: one between 5V and GND for power supply decoupling, and one between the signal (SIG) and GND for signal integrity. ...
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Which STM32F405RGT6 pins are suitable for PWM?
I plan to connect three 9g servos to the STM32F405RGT6 (datasheet) and need to select the appropriate GPIO pins for PWM output. Can I use pins PA8, PA9, and PA10 for this purpose, as these pins are ...
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Is this a good schematic for the W25Q128JVSIM flash memory?
I'm designing a PCB and need additional flash memory for the firmware, so I've chosen the W25Q128JVSIM flash memory(datasheet) and plan to use standard SPI. I've connected both the IO2 (/WP) and IO3 (/...
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ESP32 protoboard wifi not working due to jumper wires?
I made a prototype board (pics below) with a ESP32-C3 board that has a ceramic antenna. I'm a beginner for hardware stuff, but I soldered everything and it works just fine. I then made a second one ...
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Do you see anything wrong with my power circuit?
As the battery input I am using a Turnigy Nano-Tech 2200mAh 3S 25C Lipo Pack w/XT60 that fully charged is able to provide 12.6V. The ferrite bead FB1(2744555576 from fair-rite) is supposed to act as a ...
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What is this SMD 6-pins LED controlling component?
I want to build a similar, simple circuit that is switch activated blinking/flashing one or two LEDs, then it turn off automatically in about 10 seconds.
What the name of the component in this image ...
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Where is the Cf cap in this design?
I am using WEBENCH from TI for the LM2596SX-5.0/NOPB buck converter. It is a Cf cap in the "BILL OF MATERIALS" that doesn't appear on the schematic. Do you know where is that from?
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How to choose the parts for this LM2596S-5 buck converter?
I am using the LM2596S-5 buck converter with a +12V input from a Turnigy Nano-Tech 2200mAh 3S 25C LiPo battery (with an XT60 connector). My goal is to achieve a 5V output with a maximum current of ...
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Maximum circle in Altium [closed]
I want to draw big circle with radius = 1329mm. But cannot work in altium. And what the maximum size of circle in altium?
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Can a "sharp turn" on a trace with an SMD resistor also present a risk of reflection?
I'm aware that in transmission lines, taking sharp 90-degree angle turns are a bad idea. Below is an example of different current behaviors of high-speed transmission lines from various shapes of ...
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SD Card Writer Attached to ATmega328P Not Working Despite Success Using Arduino Uno [migrated]
I've designed a custom circuit board using an ATmega328P, which I intend to use for writing data to an SD card via a reader/writer module. When I initially tested the SD card reader/writer with an ...
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Can an ESD protective surface cause damage to powered on electronics?
I want to connect bare hard drives which are meant for internal use via a SATA/IDE to USB adapter or something similar. That means that the drives will be operating outside of any sort of casing.
The ...
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111
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Empty Spaces on PCB
I'm designing a PCB for the first time, and I've read it's good practice to fill blank spaces with pours, I've done this with the ground layer, but am unsure whether I should do it with the top layer ...
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Do you see anything wrong with the power section in my schematic?
I am new to electrical engineering and I would be very grateful if someone could look over my schematic and tell me if something is wrong or could be done better. In my schematic I have a XT60-M ...
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Release + replace wires in pcb connection block: on Ritto 7230 intercom phone [closed]
I have to move my house/gate Ritto 7230 intercom phone.
The connection block doesn't have any obvious release mechanism for the wires: none of the holes on the front seem to offer any possibilities.
I ...
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Is this design effective for ensuring that only one power source is active when two power sources are connected?
I found a design online that originally used a P-channel MOSFET, but I swapped it for an N-channel MOSFET. I'm not sure if this was the right choice or if it will work as expected. Any advice would be ...
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Tin "lagoon" on PCB - possible solder mask removal?
I was desoldering the PCB of a SATA connector and I got it off just fine. I happened to go over the solder and in some parts of the PCB, it looks like the solder mask has come off. There are no raised ...
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I need help identifying an SMD DFN/SON IC marking 2H 4 and 12NX
I need help identifying an SMD DFN/SON IC marking 2H 4 and 12NX,is hard to find.
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Debouncing schematic vs the placement
I have the schematic for my debouncing figured out but want to see if the placement of my components is correct.
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LMG1210 | EPC2304 High Side Gate Oscillation
I'm using the LMG12010 to drive a half-bridge comprised of two EPC2304s.
I tuned the gate resistors with no supply bus present until both the low and high side gate outputs were to my liking, no ...
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Power line crossing data lines via the ground plane
Sorry if this is a stupid questions. I have searched this and have not found a direct answer.
I am designing a Stm32 based board, mainly referencing this video: https://www.youtube.com/watch?v=...
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how it looks like when pcb damage with over power issue and components damage due to aging of pcb?
This PCB looks aged and damaged components but I doubt whether an over power issue has caused the PCB to be damaged. please can someone expert in this field explain this to me. I used the monitor ...
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Placing MOSFET heatsink on PCB?
I'm printing a PCB for the first time, and I would like to know the best way to heatsink the MOSFETs; I'm using 4 RFD16N06LESM9A surface mount MOSFETS connected in parallel:
Would it be best to mount ...
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Is it normal to be able to tear off PCB components with bare hands? [closed]
I just ordered 5 boards from a popular Chinese PCB manufacturer and (for the first time ever w/ with this manufacturer) some SOD-323 diodes and their pads and adjacent tracks were peeled off out of ...
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MOSFET Power Control Problem: DFPlayer Circuit Not Working on PCB
I built a circuit that plays MP3 files and is controlled by an Arduino. I assembled the circuit on a breadboard, and it worked, but when I fabricated a PCB, the circuit failed. The problem is that the ...
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Connecting an IC Power Pin to the Power Plane via Vias
In my design, I have a dedicated power plane. I’m wondering whether I should connect the power pin of the IC directly to the power plane polygon or use thermal relief.
Considering it is connected to ...
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How do I connect an LED with two cathodes and two anodes?
I came across an LED that has two terminals, cathode and anode. My project is a board with 38 infrared LEDs in an MCPCB that I need to design. In this case, I would like to use two 21V supplies to ...
