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.
6,794 questions
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Identify SOT-23 component marked "2A?" on refrigerator PCB (possibly transistor)
I would like some help identifying an SMD component.
The component is in a SOT-23 package (3 pins) and it is mounted on a refrigerator control board.
The marking on top looks like "2A" plus ...
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Guidance on medium-speed SPI bus over backplane
I am developing a system with multiple (four) distinct PCBs containing devices that need control from a central MCU via SPI plus a smattering of gpio and other slower signals. My plan is to connect ...
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AP63203, continuous hiccup mode (output stuck at 2.3V)
When supplying 5V power to Diode Incorporated's AP63203WU-7 regulator I am stuck in perpetual hiccup mode. My tests to identify issues are as follows:
Remove regulator and supply 3.3V line with 1V ...
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Review request SDRAM, LCD, Ethernet layout
My last review request is here Last_review
I have two question, is my SDRAM, LCD and Ethernet layout good? And why when I start simulate the SI in Altium, the result said my max impedance in this line ...
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Locating signal distortion on a high speed pcb
There is a challenge which is not described in the signal integrity books that I am aware of.
In the books the signal is passing through components of schematics.
Suppose a signal gets distorted and ...
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Review request: Capacitor discharge pulse driver PCB
I’ve designed a PCB for a capacitor discharge pulse driver intended to energise a coil to accelerate a steel ball. The goal is to achieve a high-current, fast discharge with low inductance and clean ...
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How would you assess the feasibility of a design given the PCB dimensions and total component area?
Recently, I designed a 6-layer PCB (power + digital: CAN, RS-485) where the ratio of component area to board area (both sides, excluding keepout regions) is around 0.55. There are a few through-hole ...
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Help identify small pcb component
I found this thing on the floor. It's probably 3 mm across and I have no idea what it is. It's a one piece metal cap or something. I've disassembled an xbox 360s and a toshiba c55 laptop recently if ...
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Review request my first high speed layout
this is my first project layout the high speed (higher than normal I layout).
This my board using STM32H743IIT6 + IS42S32800J-6TLI + LAN8720A-CP-TR + LCD RGB 24bit interface (which I already layout), ...
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PCB EMI Filter Layout Conducted Emissions
My question is about how much my LC filter layout matters (copper connections, proximity, etc.), and where should each part of the Pi filter be located (all together, one in each specific place, right ...
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HFSS printed PCB antenna simulation with lumped inductor boundary
I'm trying to simulate a printed PCB antenna in HFSS. I'm certainly not a model expert and sometimes feel I lack some understanding of what it required in terms of boundaries for example PerfectE ...
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Trying to Build a Tire Temperature Sensor: Schematic Review
I posted on here a while back asking for help with my schematic and got (rightfully) fried by the responses. I've been working on it intermittently for the past few months while dealing with classes ...
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PCB MIFA Mismatch: 50R (ideal) vs. (22+j42)R (layout)
I designed a MIFA for a 2.4 GHz on a standard 2L, 1.6mm FR4 PCB, based on TI's AN043. Initially the MatLab antenna toolbox sim showed a near-perfect 50R match but the physical PCB is way off. I also ...
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ESP32 Unused Pins & EMI Best Practices
I’m finalizing a PCB design using an ESP32-WROOM-32E module. The board is powered by a 5V Meanwell SMPS stepped down to 3.3V via an LDO.
I have a handful of unused GPIOs left over. I want to make sure ...
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High-side 3.3V power switch for op-amps controlled by STM32 GPIO (active-high enable)
I’m designing a small PCB with an STM32 that uses two MCP6072 op-amp chips (so 4 op-amps total). They only need to run occasionally, so I’d like to turn their 3.3 V supply on and off from a GPIO ...
