All Questions
Tagged with capacitive pcb
10 questions
0
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1
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resistor placement in inverting amplifier to minimise noise coupling
(Image is my own creation.)
I notice that an inverting amplifier can be very sensitive to capacitive and inductive noise coupling on a PCB. I was wondering whether the placement of the R1 resistor ...
0
votes
0
answers
213
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Ultra-fast load switch
I have a question that I am assuming has a very easy answer (hopefully). I am trying to turn on and off the power to a pcb really fast, on the order of 1us. My problem is that my board has some bypass ...
- 15
2
votes
1
answer
140
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Capacitive Touch Pad Design with TTP224 ic
I am designing circular capacitive touch pads of Dia:20mm driving from TTP224 IC on my PCB. There will be 2mm glass panel above Touch pads. My PCB contains other circuits like Arduino, Antenna bands ...
1
vote
3
answers
2k
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Soil moisture sensor - Interdigital (FEF) vs Coplanar
I am working on the development of a low cost capacitive soil moisture sensor which uses dielectric permittivity changes to estimate moisture.
I found that interdigital capacitor based on FR-4 has ...
- 39
2
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1
answer
1k
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PCB stackup for capacitive buttons, LEDs and other components
The design I am working on has about 30 capacitive buttons, LEDs for back-lighting, about 8-10 ICs (capsense controllers, LED drivers, MCU, etc), many passive components and coin cell batteries.
I am ...
- 21
4
votes
0
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2k
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Capacitive touch sensor design
I made a PCB with several capacitive pads to be read by IQS127.
They work, but any material I put close to the PCB surface will trigger the output, even the 8 mm glass I'm going to use.
The pads ...
- 1,450
2
votes
1
answer
5k
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PCB trace capacitance
I am designing a capacitive touch keypad using cypress MBR series. The design guide has an excel spreadsheet to help with max trace length and button dia requirements. The idea is to keep the button + ...
- 8,501
0
votes
1
answer
157
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Feasibility- Flex Capacitive Touchpad
I'm a student(don't know much on Eagle) working on a project where I need a way of multi-touch finger tracking on flexible material. Will flex pcbs work?
- 11
3
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0
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318
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Formulas for Integral Components
Formulas for Integral Components:
I am looking for "simple" approximative formulas for integral components. In particular for:
A grounded interdigital capacitor (i.e. above a ground plane and with ...
- 5,239
3
votes
3
answers
3k
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Is FR4 waterproof? What about soldermask?
I'm investigating ways of making a capacitive sensor that will operate in very moist environments, potentially even submerged. What I need is a way to make some conductive plates in a specific ...
- 3,820