Questions tagged [schematics]
The diagram that shows how the parts are hooked up logically. If your question is about a specific schematic software package, use that tag instead.
1,413
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What are those components for? [closed]
So I have three different circuits and I need to purpose of some components in them
Series resonant converter circuit. What is the purpose of Lr and Cr components ?
Variable speed/light control of ...
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Purpose of components [closed]
These schemes are not related to each other.
Can someone tell me the purpose of the Lr Cr components here?
What is the purpose of the 39 ohm resistor and 0.01uF capacitor?
What is this circuit used ...
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2
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Circuit diagrams use unit prefix symbol as a decimal point
I've seen some circuit diagrams on-line that appear to use the units prefix symbol as the decimal point. So a 6.8kΩ resistor is shown as 6k8 and a 1.2nF capacitor is shown as 1n2. Is this an ...
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Altium Variant Problem
I have variants in schematic sheet. You can see the enclosed picture. But when I right click on the Project -> Variants there are no variants over there. But I can see the schematic sheet.
How can ...
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Should I include R1 and R2 in the drawing or not?
Is it OK to leave pin 6 and pin 7 (standby/charge) unconnected if I don't plan to use indicator LEDs? I would like to make a low power board.
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Should I include the resistance of capacitors and inductors (reactance) in my schematic?
I generated a DC/DC PS circuit from Maxim Integrated, and got this output:
You'll notice that both the inductors and the capacitors have their respective resistances marked (in milliohms). Are these ...
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Line Level Amplifier [closed]
I'm looking for a circuit that will take an audio signal in at any level (higher or lower than line level) and only output line level. From what I have seen online most of the sites I have found take ...
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1
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Could someone please tell me what each of these components are?
I'm hoping someone could please identify the components in the picture below. The input is 32A, 3P from a variable frequency drive. The bottom most symbol has been identified as pumps/fans/HVAC/etc, I'...
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Add only a subset of components to PCB in KiCad
In the KiCad PCB Editor, when I click "Update PCB with changes made to schematic", all missing components are added to the PCB. How can I add only a specific selection of components? (For ...
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Calculation of series circuit elements
I have a series circuit. Should it be true for this series circuit if I true to write like:
...
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Why does Altium Designer not detect the GND node?
I'm trying to set up a project simulation in Altium Designer.
I have some circuits across two sheets:
As you can see, I included a separate analog and digital ground. I connected them in order to ...
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1
answer
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ISO/IEC Power/Ground Symbol in schematics?
Yet again, we are debating with colleagues to choose the correct power symbols in our schematics.
Some argue that using the horizontal 4-lines symbol for GND is a misunderstanding because this is not ...
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Sanity check on this DAC reconstruction filter design
I've altered a reconstruction filter circuit to use the LTC728XT instead of the AD8608 op-amp used in the example circuit below. Is anyone able to see any issues with my attempt? This is being used as ...
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2
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Unknown amplifier circuit Analysis
Does anyone know what this kind of amplifier circuit is? I am trying to analyze it by calculating its gain, cut-off frequency, and frequency response. I am not sure how to break this circuit into ...
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Power supply names
I'm studying and trying to understand Google developer board schematics, but there are a lot of redundant power supplies. This board is a carrier board when SOM is mounted. For example this:
This is ...
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Wireless charging IC
I am building this wireless IC circuit and I don't understand the term HOST, TRI-STATE an BI-STATE. What do they mean?
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Symbol for potentially dirty ground
I have a net which, although should be ground, could potentially be dirty and contain all sorts of minor noise. What is the correct way for me to denote this in my schematic?
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What is the meaning behind "wire loops" in schematics?
Looking at this section of a TI PoE schematic, you can see wires looping onto themselves by MOSFETs, like Q3 and Q5 in the figure below:
What is the purpose of these wire loops near the MOSFETs?
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Schottky Diode configuration
I'm studying some schematics about Google Coral Dev Board, and I have found this:
Where VBUS_1 comes from USB-C OTG connector and VBUS_VIN comes from USB-C Power only connector. What is the resistors ...
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Setting multi-fingers in MOSFET in series configuration in Cadence Virtuoso schematic
I am trying to figure out to set multi-fingers (nf = 3) for MOSFET (both P-MOS and N-MOS.)
I know I can increase the length directly. As connecting MOSFETs in series increases length, can I somehow ...
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1
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Why is the example schematic for TI LM5051 OR'ing controller shown from the negative side?
Since voltage potential is simply the potential difference between two rails, it doesn't really make a difference if we draw a network as going from +Vcc to ...
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Convention or IC for dynamically switching multiple paths on a PCB?
I'm trying to create programmable circuit paths (controlled via mcu), where my program can arbitrarily connect N pins on one side of the circuit/pcb to N pins on the other side. Ideally, this would ...
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Is there a convention for documenting a schematic with notes?
I want to add an explanation as to why I’ve done something a certain way (mostly for my future self) on my schematic. Yesterday when reviewing a circuit from last year, I asked myself “why the heck ...
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What are these symbols (switch lookalike + and half a disk next to small pulse)?
I'm told as a new employee in a French company to fully understand and familiarize myself with two circuits to later apply many modifications to them. I was given the schematics and I can't understand ...
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How to repeat signal harnesses in Altium?
I am relatively new to hierarchical design in Altium but am finding it really powerful as most of my project involve multiple repeated circuits e.g. I design a lot of automotive controllers and PLCs ...
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Couldn't find SPICE model of BMS
I have designed a schematic of Battery Management System and I want to simulate it before prototyping and PCB design because I can't take risk in it. the IC I'm using for it is BQ25731RSN and I ...
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Altium Harness Conflict
Has Altium fixed the issue where Harnesses override the net names and cause a 'nets with multiple names' warning?
Has anybody found a way past without net ties? I can't afford net ties at my speeds ...
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ST32WL RF Matching Network
I am adapting a minimal design based on the TTN Generic Node. I am trying to reduce the BOM and do not require the option to switch power. In the following diagram there are 4 RF signal I/O pins, 2 ...
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2
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Creating a Library for my Altium19 project
I am trying out Altium 19, but I am having some difficulty in creating a schematic and PCB library.
I am very familiar with DipTrace, so usually I download my pattern or component from say snapEDA, ...
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ESP32 IC Circuit Schematic
This is my second attempt to design a board with microcontroller chips. From my last question, I learnt a lot and this design has improved from my last one, I believe.
Once again, what can be some ...
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Why is this 4160VAC to 120VAC transformer shown as two parallel windings with crossed leads?
I'm seeking to better understand the workings of a Square D medium voltage MCC by reviewing the schematics. It operates the attached motor on 3-phase 4160VAC.
Since the unit also needs 120VAC single-...
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What do the /X.XX refer to on the pin naming in this schematic
I was looking at this development board from Alchitry and the schematic has the pin names written as in the picture below. I can't figure out what exactly the bit after the forward slash are referring ...
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2
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How is this encoder supposed to be wired?
I have this encoder: https://www.mouser.com/ProductDetail/Bourns/PEC12R-4020F-S0024?qs=sGAEpiMZZMsUJpHmmVieqHTo0n9kjhYO9zCZFTxUfRg%3D&countrycode=US¤cycode=USD
and I am trying to figure ...
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2
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Understanding part of TI AN-1839 LED Dimming Schematic
I'm trying to evaluate LED drivers for a project I am working on, and I came across this reference design for the TI LM3402/04: https://www.ti.com/lit/ug/snva342e/snva342e.pdf. The design employs a ...
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2
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Trying to add Lyontek SPI RAM to ESP32D
I am trying to add an SPI RAM to my ESP32D on my custom PCB.
On the first revision of the PCB, I screwed up, so I am trying to make it for the next revision.
The ESP32D already uses SPI to handle the ...
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2
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Why do you need resistors for components, like ADS1115?
I am trying to design my first own PCB and before I always have used breadboards or Prototyping boards. On them you use smaller PCBs, that come with the components on it, to connect it to you circuit.
...
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LTspice Netlist Resistors have TOL in Netlist
Any resistor I place in the schematic has the letters "Tol" in its netlist. I've set all my settings to default value and it's still there. It typically doesn't get in the way unless I try ...
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1
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What does this strikethrough on the arrow mean? is it not bi-directional?
I'm trying to find out if the main DSP core can communicate with an external DSP via I2S . I'm not sure what that strike-through means.
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Help to understand the operating logic of the Bosch charger
I ask for your help to:
determine, if possible, the type of transistor T5, T7 (SMD code: MK3C).
help me understand the operating role of the set T5, T7 and R23, R33 in the circuit (it's like a ...
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Is it possible to individually control each LED the way this schematic is designed?
I'm currently researching a design which includes the below schematic :
This is supposed to be an array of LEDs which are attached to the front panel of the device for indicator lights.
However, I am ...
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Geometric symbols alongside input filter capacitors on 1960's amplifier schematic
Capacitors C1, C2 and C3 are accompanied on this schematic by a semicircle, square and triangle symbol respectively. I'd expect the meaning of unusual symbols to be explained on the same drawing; they ...
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Parallel connection of V7805-2000
I am using V7805-2000 in my design. V7805-2000 is capable of producing 5V @ of 2A. Can I connect two V7805-2000 in parallel to get 4A?. In this datasheet it is mentioned as "No parallel ...
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What does a dashed circle around a connection mean?
The datasheet for the TI TPA3100D2 (a class D stereo power amp) contains a couple of these symbols in the block diagram on page 7:
I'm referring to the dotted circles around schematic lines. The ...
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Kicad assigning net names randomly
I'm running into an inconsistent behavior related to net naming in Kicad, where the same net connection (literally the same sheet duplicated multiple times in a hierarchical layout) ends up with ...
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2
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Effect of (possibly missing) grounds in power amp output circuit
NOTE: It turns out, the ground connections I wonder about below actually are connected (thanks Sim Son in comments), although I still cannot see how they could be connected (additional closeups). The ...
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Advantage of the very common electronics-lab.com linear power supply circuit
I'm in the process of designing my own lab power supply. During my research I came across a design from electronics-lab.com that seems to be very popular for DIY adjustable power supplies (here is a ...
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What is the easiest way to extract the schematics from a physical PCB?
I have a PCB containing a power amplifier. I want to extract the schematics from it. It would take a few good hours, but it is achievable. Is there a tool to help me speed up the reverse engineering ...
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ESP32-WROVER-E low-power custom board validation
I recently finished my degree in Electronics Engineering. My experience with that degree is that you learn a lot of things, but you don't go really deep into any subject.
So I'm trying to solve that ...
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Which (Zener-like) component does this diode-like symbol represent? [duplicate]
I recently stumbled upon a TI datasheet (TPIC6B595, a 595-like power shift register) where they use a diode-like symbol I've never seen.
Datasheet excerpt, figure 13 at p.12 (yellow emphasis mine):
...
2
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Why does the ESP32 DevKit has a green box?
I am trying to copy the ESP32 DevKit behavior in my own PCB (my pcb project).
I want that the ESP is powered from USB when plugged (for programming purpose only), but then powered by my external PSU ...
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