6

It's likely that this is 3 pads in a row, with the middle one connected to the IC, and the other ones connected to VBUS and GND. This allows you to take a normal 0402 0 ohm resistor and put it on either the left, or the right, connecting the IC pin to either GND or VBUS (or leaving it floating if you install no resistor). For example, for ISET2, connecting ...


6

Well the two GND pins are probably there to bring casing and everything to a defined potential; thus, performance will be better when you connect them, but it might work without. Hard to tell. However, this connection (for the low frequency of 16 MHz) doesn't need to be crazy good – a short, well-soldered wire that connects the two ground pins to the nearest ...


6

Unless there is some kind of hidden short, which would not show up on the schematic, you’ve probably got a damaged ‘595, which could have happened from ESD, a supply transient or something like that. Something caused latchup then the excessive supply current destroyed the chip. You really MUST have bypass capacitors on this kind of circuit. One 1uF for each ...


6

In your image, FIDU is the symbol's name for fiducial. Fiducials are used by optical equipment (a pick and place machine) to visually see and locate the board's origin relative to the machine's origin. A small fiducial is probably a 1 mm diameter footprint. Typically, I would place 3 on the top-side of the PCB near the corners and 3 for the bottom-side. I ...


4

This may be the answer, as I don't see anything else wrong in the schematic, and your other tests point to the transistors' not switching properly: according to its datasheet, pin 3 of the MMBT3904 is the collector, and pin 2 is the emitter; in your schematic, they have been swapped. You may want to measure the voltages between the collector and ground when ...


3

"Fidu" is short for fiducial marker. They are used on printed circuit boards (PCB) to assist in lining up the various layers.


3

So, Orcad files are, to my knowledge¹ not text files, but binaries. That makes it harder for typical source versioning software to track changes. However, having a version history of your files is still better than having to manually make copies – as long as you know which files need tracking. Git does all that – I'd recommend looking through section 1.3 (...


2

The two errors fixed, the compensating capacitor is not needed here. One suggestion is to set the frequency to around 300kHz, there are less losses than at 600kHz (R31 200k> 400k). It works nicely with these values ​​anyway.


2

There are a few mistakes. BOOT and PH connections are swapped. The catch diode is on the wrong side of coil. Compensation pin is missing a capacitor. If it is not needed, it is a good precaution to draw it, so you have a place for a capacitor if you need it, so you don't have to manufacture new boards just because you don't have a place for an important ...


2

I found a solution. In the link I mentioned below is help me about this topic. Thank you for your interest. https://resources.altium.com/p/multi-board-design-projects-in-altium-designer


2

If that is what I think it is, it is a Fiducial. They are used for the board manufacturer as a reference so that they know where everything is located on the board coordinate-wise. If you want to learn more about them, there is plenty of information online if you look up ‘Fiducial’.


1

I would guess it refers to Fiducial Marks, measuring points on PCBs for positioning.


1

The HC595 datasheets usually only specify a total current of up to 75 mA (table "Maximum Ratings"). I suppose you're trying to drive each channel there with 10 mA. That will not really work well; even if you don't have all LEDs on at the same time, when reading the datasheet you'll extrapolate that at 5V supply, and drawing more than 6 mA from Q_A ...


1

You will need to add your library to your project. The easiest method would probably be to right-click your project name and select "Add Existing to Project..." and browse to your library. If you want to add libraries to be available to ALL of your projects, click on the gear in the upper right-hand corner ("Setup system Preferences") and ...


1

Yes exactly. Those symbols dont represent actual components they are just a "bus" symbol. All it means is every symbol that matches needs an electrical connection between them. It also implies what voltage those lines should be at constantly when powered on. Usually a voltage regulator will be somewhere in the schematic if its a complete schematic. ...


1

To convert certain older (non-synchronous, like the LM2596) buck converters to a buck-boost, there is a little-known hack, that you can find in the datasheet for ST's L5973D (https://www.st.com/resource/en/datasheet/l5973d.pdf), Figure 16 (Positive buck-boost converter). This would explain the extra silicon component which is likely just a mosfet. The second ...


1

Why doesn't a charging cycle begin, when the MPP voltage isn't reached? Best guess: A solar panel is a current source over most of its characteristic; the output voltage is set by the input impedance of whatever charger is connected to it. MPPT in this IC probably works by reducing the current it delivers on the output until the MPP is reached. If it can't ...


1

User definable Lithium Ion charger This circuit is "out of my head" and will probably need some 'minor playing', assuming I've not done something really silly. As shown there MAY be stability issues, but maybe not. Some tweaking (loop gain, capacitors) may be in order. At first glance this may appear far more complex than eg TP4056 type chargers ...


1

You can try to make your own charging circuit based on LM334 constant current source. Maybe. It's just my first idea. You need to sense battery voltage all the time to avoid overvoltage. And LM334 is, as it stands in its name, provide constant current. When battery reaches 4.2 you have to go to constant voltage mode, where current must fall, which is a ...


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