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2 votes

What is the best solution to keeping heavier components on a double-sided PCB while going through second pass reflow?

As a last resort, if the techniques mentioned by V. Spike don't work for you, you can use glue, typically it's red in colour (perhaps for visibility). Here is one supplier, there are others such as ...
Spehro Pefhany's user avatar
2 votes

What is the best solution to keeping heavier components on a double-sided PCB while going through second pass reflow?

Put all heavy parts on one side of board Handsolder heavy parts Use dual temperature solder processes (use a higher temp solder for the one side of the board and a lower temp for the final pass)
Voltage Spike's user avatar
  • 84.6k
0 votes

How to continuously vary inductance in the range \$[-A, A]\$, A>0?

Yes, you can build circuits using active devices that behave like inductors, both positive and negative. It is also straightforward to make them variable. One implementation would be to use a classic,...
user69795's user avatar
  • 1,600
1 vote
Accepted

Unknown SMD component - PCB Designation question

I think it's a capacitor, the frequency doesn't change the capacitance, it looks like a cap. It's most likely not an inductor or ferrite. You could be more sure if you had a more complete LCR meter ...
Voltage Spike's user avatar
  • 84.6k
3 votes

Tinkercad multimeter doesn't work

In the top example, you're shorting out the LEDs with two ammeters. The approximately 9mA (9V/1kΩ) flows half through one and half through the other. Note: please learn to use an ammeter correctly ...
Spehro Pefhany's user avatar
14 votes
Accepted

What is this component - 8 legged inductor?

It's not an inductor. It's a transformer for a DC/DC converter, made by Epcos which is now a part of TDK. Likely a custom order product for this specific product so likely no public data sheet ...
Justme's user avatar
  • 158k
0 votes

Need help implementing a 16x13bit ROM

Consider a Silego (Renesas) GreenPAK device. These are small-footprint "programmable FPGAs" that could easily implement a 16x13 LUT. GreenPAKs have an array of lookup tables of various sizes ...
hacktastical's user avatar
  • 54.9k
2 votes
Accepted

What is this component? (datasheet)

It's a a Jieli (杰理芯片) Bluetooth MCU, probably a AC6965E. I think it's a AC6965E, because the marking characters after the dash seem to match with the last characters of the product number on Jieli ...
nanash1's user avatar
  • 5,862
2 votes

Need help implementing a 16x13bit ROM

Excellent question! The ROM is small enough to have several fonts and get it done with TinyTapeout and you get a custom IC! That’s on a hobbyist budget. It will need an external parallel-to-serial and ...
Kuba hasn't forgotten Monica's user avatar
9 votes

Trying to determine what this small glass-enclosed item is

Context from the surrounding circuit is worth looking at: CN1 (fused, 'L') and CN2 ('H') are single-phase connections to the line filter (yellow 'X' type capacitors, common-mode chokes) and remaining ...
Tim Williams's user avatar
  • 39.2k
8 votes

Trying to determine what this small glass-enclosed item is

It's a gas discharge tube arrester for circuit protection against surge voltages. Image credit: DigiKey / Mitsubishi Here's another, from a Mitsubishi TV board, that is closer in looks to the item in ...
vu2nan's user avatar
  • 18.8k
0 votes

Altium annotation - no changes were made

You want to try and have it look for more changes than just comments and library reference. Altium will only generate changes on what you tell it to check. That goes for ECOs and DRC checks.
Voltage Spike's user avatar
  • 84.6k
18 votes

Trying to determine what this small glass-enclosed item is

It's a gas discharge tube. Used for e.g. lightning surge protection. They are sealed tubes of noble gas which are designed become conductive when a high voltage spike occurs. The GDT then provides a ...
Tom Carpenter's user avatar
7 votes

Identify an IC labeled LB21

It is a LM317LIPK from Texas Instruments (marking "LB", "21" is a datecode). Picture from lcsc:
vivier's user avatar
  • 1,083
2 votes
Accepted

What are the purpose of these components on my car ECU?

I don't know for sure, but I suspect they are to deal with vibration which is an issue in the automotive environment. You will note that it is applied to the most massive capacitors only and they have ...
Spehro Pefhany's user avatar

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