New answers tagged pcb-design
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Relay Switching Problem when load is connected
this could be an elecrical noise problem going to the capacitive touch, from contact bounce.
you may have better ideas. mine:
A) don't poll the capacitive touch ic as often (stop short cycling)
B) ...
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Hole through half of PCB in Altium
Altium supports counterbore hole features for exactly this purpose! This is described in the Pad Features section of Altium's Working with Pads & Vias documentation.
Here I have created a 3mm ...
- 11.5k
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Is a +16.8V gate drive safe for a MOSFET with +-20V V_GS rating?
16.8 V is fine for typical MOSFETs with 20 V absolute max gate-source voltage. It may delay your MOSFET turn off slightly, so if the MOSFETs are in a bridge, be sure to have sufficient dead time to ...
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Power return pins for the Allwinner R11
On many EDAs the component symbols have 129 pins where bottom ePAD is pin 129 and labeled as GND.
So the bottom pad is the only ground pin, and this is common for chips in similar packages.
- 196k
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Power return pins for the Allwinner R11
From the datasheet linked in the question section 3.1. Pin Characteristics has:
Type defines the signal direction: I (Input), O (Output), I/O(Input/Output), OD(Open-Drain),A (Analog), AI(Analog
Input)...
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Car strobe unit PCB with 8 LEDs schematic check
Your TVS diode D1 is a 58V version. Which means it will clamp slightly above 58V. The problem is that 58V is larger than the maximum allowed voltage of almost all the passive components that follow. ...
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How do you decide the correct trace width in PCB design?
You might find your answers from a suitable PCB design software tool. You can then enter currents, frequencies etc. and get PCB specifications for tracks, vias and all sorts.
Try the free Saturn PCB ...
- 25.4k
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How do you decide the correct trace width in PCB design?
Use the largest trace or pour that fits the board size and clearance rules, unless:
impedance control forces you to use a specific trace width
solderability would be compromised too much (usually not ...
- 25.4k
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How do you decide the correct trace width in PCB design?
There is not a single universal rule for trace width. It really depends on what the trace is doing. In practice, these are the main things you can look at:
Current: For power traces, current is ...
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Hole through half of PCB in Altium
I need a mechanical hole that starts at the bottom of my board and has a depth of 0.4mm.
That's not really a hole, and it's not a blind via. It's a milled slot/recess. Many PCB shops can do milling ...
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Hole through half of PCB in Altium
Found a way to do this:
Created a new footprint. Instead of adding a pad I added a circle on the mechanical layer, selected the circle, clicked Tools > Convert > Create Region form selected ...
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Hole through half of PCB in Altium
This is called "back drilling." Altium's web site has an article on back drilling. This is done through setting up rules for Maximum Via Stub Length (Back drilling). This technique may not ...
- 13k
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High Voltage PCB for Electromagnetic accelerator / Coil-gun
First: STOP. You need to really think through all the hazards in such a device before proceeding. This type of circuit can produce lethal voltages and currents, as well as other hazards (explosion, ...
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ADG819 output voltage collapse
I would buzz through your PCB against the breadboard. You will find a missing connection, or some ground connection being provided by test equipment on the breadboard version.
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High Voltage PCB for Electromagnetic accelerator / Coil-gun
I would not, personally, use PCBs for such a device, given the extremely high current pulses generated. I used to build high-power experimental radio transmitters, running at 3500v with 100uf worth ...
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High Voltage PCB for Electromagnetic accelerator / Coil-gun
You appear to be using parts (terminal block, tact switch) that are unsuitable for the working voltage. Fortunately, the terminal block appears to have failed before allowing you to attempt to operate ...
- 28.5k
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Should I use tracks or copper pour for mains line connection between two points?
Using a copper pour for a 16 A line is perfectly fine as long as it’s done properly. If space is tight, a wide pour on both layers with regular via stitching is a solid choice: it lowers resistance ...
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Should I use tracks or copper pour for mains line connection between two points?
Pours do not always create a better connection. They may increase width and add thermal headroom.
It is generally discouraged to use only pours for electrical connection because then the connection ...
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How do you you turn off all test fields in PCBNEW except for the ident?
One possibility would be to choose Edit -> Edit Text and Graphic Properties for mass-editing of specific fields only.
For example select ...
- 10.3k
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M.2 B-key card: how to report as "self-powered device"? Additional components?
but I've seen USB-cards (like this), that seem to have solved that problem already.
Not standards-compliant, probably. You being able to buy a device on Aliexpress has a damn low correlation with the ...
- 111k
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Calibrating phase shift of multiple RF circuits
A peak to peak phase variation of 5º sounds tight enough to me, but if you want to play around with phases, there is a way to tweak them on your PCB, exactly as you mentioned.
The method involves ...
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Is it safe to route top layer traces under header pins, SMD IC?
From a manufacturing perspective, this routing method is acceptable (assuming red is the top surface and blue is the bottom surface). Because except for the hole rings of the soldering holes at the ...
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Altium diff routing problem
You don't; Interactive Routing is always octagonal to screen coordinates.
You could route one section, rotated to an orthogonal angle, and copy-paste the routing to other angles. This is particularly ...
- 53.1k
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Altium diff routing problem
While routing the track, you can press the Shift + Space keys to change the corner style of the tracks.
You can view the corner style in the Properties panel while routing is active.
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Can I put ground and signal on the same layer?
First, the cost of four-layer boards isn't significantly higher than double-layer boards—perhaps only about 1.5 times more—making it worth reconsidering. Second, I believe signal routing crosses paths,...
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Can PCB mounted device touch bare 230VAC copper?
Yes, it is fine. The bottom side is a combination of plastic molding and epoxy resin (around the pins and the periphery), both of which are excellent insulators.
By doing both top and bottom parallel ...
2
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Accepted
How to remove guides in Altium PCB editor?
You can add, edit, and remove guides in the Guides Manager section of the Properties panel (on the General tab).
Make sure this particular panel is visible by going to View > Panels > ...
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MCU crystal layout
It should work just fine.
In most strict application notes for MCU crystal layouts, the crystal ground plane is drawn as a separate island and only connects to main ground plane right through the MCU ...
- 196k
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MCU crystal layout
I don‘t see your question here, but in case you want to know if your design looks OK I can say yes, all good.
- 11.6k
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Startup current vs LDO capability
The key spec you're looking for is the max current limit:
So the max guaranteed current this LDO can deliver (assuming it doesn't go into thermal shutdown/limit) is 250 mA. Beyond that the output ...
- 25.5k
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Can PCB mounted device touch bare 230VAC copper?
Yes, it can touch bare copper because the body of the relay is a non-conducting material i.e. plastic. However, it's impossible to say that your PCB is adequately designed to provide sufficient ...
- 502k
3
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Trace width calculator, current values shown
For a given current(in the trace calculator kicad or saturn pcb toolkit) if i give 10mm trace width and I get 5A of current is it the continous current that i can take out or is it the peak current ...
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Routing techniques for FFC breakout
Not in this picture are the other components (SSD1963, ESP32, Clk etc.). I have messed up circuit boards before in the early stages of prototyping, hence I am designing this board to be able to be ...
- 53.1k
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Routing techniques for FFC breakout
There are some rooms for improvement.
The bottom layer
Because your signals are not "DC only" but toggling at 40MHz, you have to consider the return currents.
Long story short: Put a ...
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Will this circuit work properly?
About your communication circuits (I2C and SPI) I am assuming that you are placing series resistors for Electrostatic Discharge (ESD) protection. This is not the most effective solution because series ...
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Will this circuit work properly?
A common gotcha on STMicro MCUs is the oscillator transconductance.
You may want to check the ATS08A datasheet and compare to the MCU datasheet and related appnotes, especially AN2867 - Guidelines for ...
- 53.1k
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Will this circuit work properly?
No, it will not work properly
C21 is misplaced, should be connected like C9
C4 is misplaced, U4 will not receive a supply this way.
C19 is misplaced, U5 will not receive a supply this way.
C20 is ...
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LPDDR4 T Branch topology layout routing length match
yes. Remember why you need align things: so that the signals arrive within a small window of time; since there's only one strobe and it is for all the address bits, all the address lanes need to have ...
- 111k
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PCB trace width compared to wire gauge
There's a bunch of factors at play here.
The two that are probably most salient are that:
First, your external wiring is designed for all of the bumping and battering it'll get over the product ...
- 49.5k
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