5
votes
Accepted
What is a "mechanical pad"?
The "mechanical pad" is where you attach the housing of the flex connector you are using.
The adapter board is not intended to have the flex soldered to it.
The idea is that you solder a proper ...
- 73.6k
5
votes
Accepted
Integrating two I2C sensors into a single circuit
If you follow the best practice that the decoupling capacitors should be as close to their chip as possible it should be clear that you would not combine the capacitors. Keep the separate caps with ...
- 57.9k
5
votes
Accepted
Does anyone know what CJMCU on breakout boards means?
It's just a brand name as pointed out in the comments by CL..
cjmcu.com
- 119
4
votes
What are the reasons why this analog to digital conversion is inaccurate?
Vcc is the power supplied to the Arduino. The ADC does measurements relative to Vcc, so if Vcc changes 10%, the values reported by the ADC will change approximately 10% (the other direction). Vcc ...
- 3,105
4
votes
Should I short these ground pins together?
If you need to follow FDA rules (or similar) because this is a product, then there are requirements that should be followed if the design is to be used in a product.
In many designs the MAX86150 is ...
- 88.8k
4
votes
Accepted
How can I attach a USB microphone to a Breakout-board using ADC Ports?
You can't. The USB "Microphone" is actually a microphone, an amplifier, analog filtering, an ADC of its own, a bit of digital signal processing and a microcontroller that speaks the rather complex USB ...
- 100k
4
votes
Accepted
Can you physically connect an FPC to a FFC socket that has the same pitch but more circuits?
Physically, yes, you can.
But, electrically, the FPC is likely to be misaligned in the FFC socket, therefore either shorting adjacent circuits or not making any contact.
So, not advisable.
Instead, ...
- 25.6k
3
votes
Accepted
Critique of first PCB project
please specify the direction 'electrical type' for the relevant pins in your symbol
Always include a frame in a schematic
when dealing with ICs just break out connections by making a net / wire at a ...
- 110
3
votes
Why do SparkFun make breakouts for circuit multiplexers?
Because sometimes you want to prototype with the newest or devices with more features. Hobbyists often do not have access to in house fabs just for initial prototyping, while they will eventually get ...
- 73.4k
3
votes
Accepted
White dust on chip pins
That looks like residue from something like safewash water based flux remover. Or residue from washing after using a water soluable flux. The residue is only in places where surface tension would hold ...
- 1,747
3
votes
USB-C used only as analog tranmission line and not as intended?
The USB-C to USB-C cable can't be used as an arbitrary transmission line.
The VBUS bandwidth is limited because the cables are mandated to have bypass capacitors between VBUS and GND.
There are also ...
- 172k
2
votes
How to discern quality of a breakout board? other than proper soldering on back of board
How would i know which is of higher quality?
Quality, in this context, usually means life expectancy and life expectancy is dependant on many factors such as: -
How the boards have been handled ...
- 473k
2
votes
How to determine necessary electrical components for breakout board
Many times, what you are calling a breakout board is in fact a complete circuit.
The other parts are all the things needed to make it work - often implemented from a recommended circuit in the ...
- 73.6k
2
votes
Accepted
ESP8266 not running uploaded Arduino sketch
Thankfully I got it to work by changing the "Flash Mode" setting in the "Tools" menu to "DOUT" and it seemed to have done the job. I'm not sure if this was relevant was well, but I also changed the ...
- 131
2
votes
Accepted
Cortex-M0 vs. Cortex-M0+ for an IoT sensor using LoRA
It's not really possible to answer this question accurately, because neither you nor the article you link to provide any sort of useful definition of 'deep learning'. Depending on who you talk to, ...
- 5,117
2
votes
Simple RF-powered LED circuit works on bread board but not perf board
Pluggable breadboards have some capacitance between nodes. The perf board will have substantially less of this internode capacitance. Maybe you need to experiment with the perf board and some small ...
- 57.9k
1
vote
Why doesn't my pull-up work on S-35770 I2C counter IC?
I changed the resistor to 4.7k and it's working now. Not sure why is that, but this solved it pulling RST up.
- 61
1
vote
Looking for a way to connect wires to a breakout board without soldering
Google friction fit pin headers.
- 2,915
1
vote
Should I short these ground pins together?
The issue of separated grounds in ADCs and DACs is a common one. The idea is to avoid 'digital currents' flowing into the analog ground and vice versa thereby corrupting them.
Your specific question ...
- 1,048
1
vote
This L293D just blew up. Can someone please help me figure out why?
Least thermal resistance with a L293 is to the centre/ground pins.
These should connect to a heat sink - think 6 cm² (1 square inch) of 35 micron copper - this should reduce resistance from about 80°C/...
- 2,056
1
vote
Accepted
Low Profile PCB Connector Identification
Looks like FFC/FPC connectors.
These types of connectors are commonly used with camera sensors, LCDs, screen digitizers etc.
The connectors mostly come in SMD configuration and use flex cables for ...
- 2,162
1
vote
Accepted
Why did Adafruit pick a 10K resistor for this phototransistor breakout?
The datasheet says that the
loading resistor shall be chosen to meet the requirement of maximum ambient light, and output saturation voltage
However, Adafruit cannot know what ambient light level ...
- 20.1k
1
vote
Accepted
BGA break out and impedance control
For SDRAM interfaces, the exact impedance of the wires is not important. Actually, very few designs I know even care about this. Most you will see is a 10-30R series resistor to keep reflections at ...
- 1,256
1
vote
BGA break out and impedance control
Assuming layer 2 is your reference plane....
Can you specify a thinner spacing between L1 and L2?
This is the usual fix for this sort of problem as a thinner gap between the layers will make the ...
- 17.6k
1
vote
How to determine necessary electrical components for breakout board
A breakout board is designed to ease interface functions for some limited purpose. A VLSI digital IC such as an ARM chip will have a great deal of analog components inside for clocks and PLLs, but ...
- 148k
1
vote
How to determine necessary electrical components for breakout board
Sometimes, components are external to the IC because they're difficult or expensive to make with the IC process. Sometimes external components are use to program the IC to do certain things.
...
- 174k
1
vote
Accepted
Removing pull-up resistors from breakout board
Based on the excellent answer by @SamGibson (and his comment with suggestion), I realized the VIN trace is only used to feed the voltage regulator and those two pull-up resistors. So I could cut the ...
- 167
1
vote
Removing pull-up resistors from breakout board
Is it [possible to remove the I2C pull-up resistors] "by hand" (I do have that fine tip for soldering but not much experience with miniature soldering)?
I think I've reverse-engineered the schematic ...
- 18.3k
1
vote
Accepted
Best way to connect two adjacent PCBs by their outermost hole rows?
For staple-shaped connectors you are either looking at:
U-Shaped Headers. For example, Farnell sells them as Board-to-Board connectors, such as these here.
Solder anchors. Digikey sells these, they ...
- 373
1
vote
Best way to connect two adjacent PCBs by their outermost hole rows?
It depends how many units you intend to produce, if this is a one off, bent zinc-plated paper-clips are cheap, easy to solder and very strong.
just make staples out of paper-clip wire and solder them ...
- 36.4k
Only top scored, non community-wiki answers of a minimum length are eligible