Questions tagged [flex]
16 questions
4
votes
2 answers
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 bonding a flex to the surface of a rigid PCB? Can we…

Leo Atreides
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3
votes
1 answer
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 rigid-flex PCBs.
One thing that I haven't been able…

DCrown
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2
votes
1 answer
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 the polarities. What are the terminals?
Image…

BHP
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1
vote
1 answer
What schematic symbol is used for a flex cable?
Generally asking, but primarily for KiCad, what is the schematic symbol typically used for FPC/FFC/flex cables?
That is to say, the flat end which is sometimes stiffened and does not have a connector like in the following image:
In KiCad, would the…

Daniel
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1
vote
1 answer
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)
Core (Polyamid) 25µm – 50 µm
CU 35µm…

Alexander Ohm
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1
vote
1 answer
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 potentially starve the solder joint of solder. I…

jsmith0910
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1
vote
1 answer
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 manufacturer is here:
Please note that I am asking…

Ahmed
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1
vote
0 answers
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 the pads on the PCB as SMD rather than NSMD, but I am worried…

Vinzent
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1
vote
1 answer
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 above. Here is another picture with the part I’m…

Filippa
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0
votes
1 answer
Flex boards routing inside device housing
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 inside the device. What software do they use? Do…

Tommy
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votes
0 answers
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 voltage follower circuit?
And what is the probability…

Raghav Kumar
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0
votes
1 answer
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 DFN parts.
Flex cable is 4mm wide and 200mm long and has…

tipo1000
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0
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0 answers
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 electronics.

Kaizer Sozay
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0
votes
2 answers
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 way to go?
Can they really be that accurate or…

Brandan B
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0
votes
1 answer
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 button in one layer and the other contact in another…

vram
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