Questions tagged [flex]
The flex tag has no usage guidance.
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Most probable cause for unwanted capacitance on serial line?
I'm a PCB rookie and just got the first sample of a 4 layer flex-rigid board that I made.
I'm using 3.3V TTL-UART @ 115200 baud, the stackup is as follows:
CU 35 (signal)
Prepreg 0.7mm
CU 35µm (GND)
...
- 321
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Flex boards routing inside device housing [closed]
I have seen several dslrs such as Nikon teardowns and I really admire the way they design the flex cables and FPCs. What I'm wondering is how do they manage to design such complex flex shapes
folded ...
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How to simulate output and noise of a flex sensor?
I am creating a sign language glove. To train the model, I wannat to use a video dataset and simulate the input of the glove.
What is the mathematical formula for the output of a flex sensor in a ...
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Can UL 21147 and UL 20624 type flexible flat cables be used interchangeably?
I need to replace a UL 21147 flexible flat cable in one of my devices but can’t find any in stock.
After searching online, I could not find any UL 21147 type cables and only found UL 20624 type cables....
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What are the concerns of vias-in-pad on flex PCB without filling?
My PCB fab said they can't fill the via-in-pad for flex PCB. The min hole size is 8mil with 20mil diameter. From google search, the concern is the solder will be drawn into an open via which could ...
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What does "P+ ID P-" mean on this battery flex?
My nokia 6.1 plus battery has these labels on it's flex. The phone has been off for about a year and doesn't get ON so I want to shock it's battery. The problem is I do not know battery terminals and ...
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259
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How to design FFC's/FPC's Even/Odd pattern in Altium
I want to design the even/odd pattern of FFC (flexible flat cable) in Altium. I don't know the exact term used to describe it, but the recommended drawing of this FFC from its target connector's ...
- 161
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Stiffeners needed under DFN parts in flex PCB?
This is the first time I'm designing flex PCB and I wonder do I need to put "stiffeners" under DFN parts which are soldered on flex PCB? Stiffeners would be on opposite side of flex PCB than ...
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Fine-pitch SMD pads on flex PCB using coverlay rather than soldermask
SMD: "Solder-Mask-Defined"
NSMD: "Non-Solder-Mask-Defined
I am making a thin flex-PCB (0.2-0.3 mm) on which I am going to mount a component which has SMD pads.
I would like to also make ...
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2k
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How to bond flex to rigid pcb
I have a rigid PCB and a flex (4 layer) PCB. I want to bond them instead of using a connector (although if what I am expecting is impossible I will use a connector).
What methods are available for ...
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126
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How to connect five flex sensors to on esp8266?
I’m using a lolin nodemcu 8266. I was wondering if it is possible to connect 5 flex sensors to one node (to make a glove which detects finger gestures).
I’m an experienced programmer but new to ...
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225
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Purpose of solid plane on flex in wireless earbuds
I'm looking at a teardown of Sennheiser Momentum wireless earbuds. It is a rigid-flex design that folds into the casing:

My question is about the flex that sticks out to the right in the picture ...
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526
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Hexagonal hatched polygons Altium
I'm recently trying to design a flex PCB. I haven't been able to find any specific tutorials on how to do this in Altium. But I did find Altium blogs detailing some of the best design practices for ...
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How accurate are flex sensors?
So for the project I am working on I plan on measuring very precise changes in angle, possibly up to 5 degrees of accuracy.
Are polymer ink sensors (the classic Nintendo power glove flex sensor) the ...
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262
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I need to do a membrane pcb for a keyboard or a flexible PCB like a membrane PCB
I need to design a membrane PCB for a keyboard and/or flexible double sided PCB that works like a membrane PCB. My problem here is that I don't know how to do the buttons, with one contact of the ...
- 148
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354
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Thickness for polyimide stiffener in flex pcb
I'm struggling to find some guidelines for the thickness to specify for a polyimide stiffener under a surface mount connector on a flex board. I see lots of call us and we'll help you figure it out ...
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