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.
1,633
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Altium Efficient Usage of Signal Harness
I have a 16-channel differential analog input which I would like to represent through a signal harness (see below). I am new to Altium, and I am curious if there is a trick to define my harness more ...
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Diode and bipolar NPN transistors orientation not correct, says JLCPCB
JLCPCB is telling me 4 components are incorrect but when I look over it and the datasheet it all seems correct to me.
My original | JLCPCB corrected:
This is what my current board looks like:
My ...
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Do non-polarized capacitors need to be in any type of orientation?
I have submitted my PCB design to JLCPCB for population. They are asking me if the orientation of my capacitors are correct:
My PCB and schematic of it:
In the datasheet it states that these are non-...
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Aircraft Simulator Intercom [closed]
I'm new in trying out electronic projects and I am an aviation enthusiasts. I'm trying to build my own "Intercom" system for my simulator that is connected to a PC but I am lack in ...
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3
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NE555 + CD4017 Airplane Strobe Light with LDR
Engineers! I have built a simple airplane strobe light using NE555 and CD4017 in order to flash two LED in a different pattern. I have added an LDR resistor with a transistor in order to switch OFF ...
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How to understand schematic circuit diagrams in functional safety
I'm having a hard time understanding the kind of diagrams which frequently appear in literature relating to ISO 13849.
Are there relevant instructions or guides on how to understand this kind of ...
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Where can I follow new developments in electronics? [closed]
I can say I am new one in electronics. Is there a site, magazine, forum, etc. where you follow current developments in the field of electronics? I am particularly interested in PCB design. I would be ...
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PCB from circuit diagram [closed]
Can anyone please explain why this U1A and U1B is there and how can it be converted into a schematic in Easy EDA?
(Source: https://m.media-amazon.com/images/I/610mQaFartL._SX522_.jpg )
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LED "optical noise" when powered by DC
I am currently designing a circuit where:
An LED driven by a constant current driver shines directly into a photodiode. (I have also tried without the op amp constant current circuit.)
The photodiode ...
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ESP32 custom board review
I have just finished the electronic design of my project and would like to request a review from anyone with more experience in PCB design. It's a custom development 2-layer board based on the ESP32-...
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Setting VBUS_MIN and ISNK_COARSE/FINE on an Infineon CY4535
I am using the Infineon CY4535 EZ-PD evaluation kit to power a 5V, 3A device from a USB-C source. I am having trouble reconciling schematics and tables given in the documentation (PDF link here) that ...
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Removing HSE backup crystal from ST RF module
I'm currently examining the reference design schematics from ST, available at en.MB1389-WL55JC-highband-E02_Schematic. In the schematics, the EXTERNAL HSE CLK with TCXO configuration is linked to the ...
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How should I interpret this DP3T switch diagram?
Which pins are the poles and how are they connected in the three positions of the following switch?
Datasheet for DP3T Switch (SLW-993515-2A-SMT-TR).
I'm just not sure how to read this schematic:
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Understand interphone 4+N wiring and arrow symbol
Could anybody help me understand the attached interphone 4+N wiring? specially the arrow symbol crossing a two segments right angle, what it means, what is it connecting?
I have an issue with an ...
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SWD Connection to MCU and Appropriate Configuration for Reset Pin
I aim to establish a connection between SWD header and an STM32 MCU on PCB, having identified the relevant pins on MCU (SWO, SWCLK, and SWDIO). I have two inquiries:
Is it appropriate to connect ...
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What is the purpose of these Schottky barrier diodes connected with reverse polarity between the Vin line and gnd?
On the laptop's PCB I see two Schottky barrier diodes connected with reverse polarity between the Vin line and gnd. What is the purpose of this?
At first I suspected that it might be a TVS or a Zener ...
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Explain schematic for one-shot trigger
Can you please help to explain following schematic:
How does this circuit work?
What is the purpose of the diode and the capacitor?
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What is this weird split circle symbol in a schematic?
I saw this weird symbol in a schematic and I couldn't find what it means.
It was connected from one side to the shield and ground of a USB port.
From the other side it was connected to the ground of a ...
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Meaning of 'POL' on component?
I have this component on a schematic and no idea what POL means.
Here is the a more complete schematics of this washing machine:
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What does mean NC in an schematic and BOM?
I am reading this datasheet to implement that IC for an USB-C PD module to charge a 2-S battery pack, but I have the doubt in the schematic (page 11). There are some capacitors with value NC which I ...
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Identifying different connector symbols in French circuit diagrams from the 80s
I'm trying to troubleshoot an old analog oscilloscope (Metrix ITT instruments OX 725), which seems to come from the late 1980s in France.
There is (part of?) a service manual with circuits diagrams ...
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How to amplify ultra high-frequency signal
I have found some schematics to amplify ≈100 MHz signal, but can't find a schematic for 2.4 GHz and higher, up to 5+ GHz. The main problem I face is that I can't find a transistor fast and powerful ...
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Which wire is hot?
I have an analogue oscilloscope that had its power cable head chewed off by something. Before I replace the cable, I want to be 100% sure which side of the cable is hot and which is neutral. This is ...
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ATmega64 custom board is not programming
I have designed a custom board for ATmega64 as below:
It's the first time I want to program it, and I get a "chip enable program error". I can program ATmega16 and ATmega8, but for ATmega64 ...
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Schematic Review: Interfacing ADS1299 with Seeed XAIO NRF52840 sense?
I need someone to review my schematic and guide me to fix the problems in the schematics.
Need help reviewing the schematics.
Can I power the ADS1299 with Seeed Xaio? If not, then how? I asked this ...
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Altium: possible to connect two repeated sheets?
Can two "Repeat" ports in two "Repeat" sheets be connected?
In other words, can I have a repeated sheet, where each instance has a unique sheet entry, and connect them one-to-one ...
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Why Intel 4004 published schematics uses NMOS, if the 4004 was produced only with PMOS?
According to Wikipedia[0]:
The 4004 employs an 10 μm process silicon-gate enhancement-load pMOS technology on a 12 mm2 die[36]
In 2006 Intel released original schematics of 4004 CPU [1]. Seemingly ...
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DPDT toggle switches vs DPDT slide switches
I am wondering if all DPDT switches function the same or if they can differ. I am looking to replace a slide switch with a toggle switch but I am unsure if the circuitry is the same. In the attached ...
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Electromagnetic Pendulum Pulse Driver - Having Trouble Getting Circuit Running
Now I'm not super well versed in circuits though I've dabbled a bit in some circuit building in the past. I'm working on an electromagnetic driven pendulum for a clock I'm building. The Schematic I'm ...
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RTL viewer diagram shows no logic gates
I'm trying to write a Verilog gate-level description of this circuit:
My code is here. I compile it on Quartus II (there is no error):
...
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Don't understand a symbol in this circuit
I'm trying to fully understand this circuit. I don't understand how the connection from the power source is going into the center of this coil. What does this represent?
The circuit is for an ...
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What is this strange symbol in this IC block diagram that looks like a rectangle inside a buffer?
I am not sure what the below symbols of a buffer looking symbol with a rectangle inside are:
This is from this datasheet here on page 11 of 13.
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What is the origin of negative offset in this amplifier circuit?
I'm working on a class AB power amplifier for a school project. The desired specifications are a load impedance of 4-16 Ohms, 1% Total Harmonic Distortion (THD), and 10W amplification.
The input ...
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USB pin connection in ESP32 PCB schematic
I want to know about the VBUS pin connection of the USB connector. I have an ESP32-S3-DevKitM-1 board.
https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/hw-reference/esp32s3/user-guide-...
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What is purpose of this diode?
Recently, I was exploring methods to distribute power akin to EURORACK systems, and I stumbled upon this schematic.
I've attempted to grasp the role of diode D4 in this setup, but regrettably, I've ...
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Why do we need multiple capacitors in parallel instead of a single equivalent capacitor? [duplicate]
I am trying to read and understand the below Raspberry Pi schematic to validate some of the basics I learned recently regarding passive components and how they are used in real schematics.
When I ...
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Custom STM32 board can be programmed via USB DFU, but no connection via ST-Link
I have spent a fair bit of time trying to understand why the stlink does not to see the STM chip when conected over serial wire (port is shown under 'Com ports' in the schematic). I have tried the st-...
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Reverse engeneering the control of an inductor
I tried to make the schematics of a toaster of mine. I don't have access to the toaster anymore but here is a part of the schematics I got.
It shows the control of the inductance that acts as a magnet ...
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What is this symbol for?
It looks like a connector, or as the diagram is about a dynamo, a light.
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My first schematic of a 2-channel relay board [closed]
Hey all this would be my first try at creating a schematic in KiCad.
The schematic is a basic 2-channel relay.
The inputs are automotive 12v and gnd. This gets converted to 5v by the K78L05-1000R3.
...
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What are some best practices for library management for schematic and PCB design?
Most CAD packages use a "symbol" and "footprint" library approach when it comes to designing schematics and PCBs. Some (like recent versions of Altium) have "component" ...
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Which signal should be fed into the single ended input of the PAM8320?
I'm feeding audio from this DY-SV17F module into this PAM8320 amplifier.
The configurations I believe I can choose from are:
1: Feed either DACL or DACR from the module to the amplifier.
2: Combine ...
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What logic function performs this IEEE Standard 91-1984 symbol?
I'm thinking about copying network interface card for an old HP9000/300 series computer. These cards are insanely expensive on ebay these days (around 200USD), and i think that i could make one for ...
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Tolerance on a resistor when looking at a schematics
In the schematics at the end of this document, there are a bunch of resistors. The author says in a footnote:
Part Notes, All Pages:
Unless noted:
Resistors are 5%, 0.12 W, or better, for standard 5%...
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Confused about STM32 FMC pins for SDRAM
Context: I am currently working on a design that is centered around the STM32H723ZGEI6. I chose to opt for 32MB of external RAM via the IS42S16160J SDRAM IC. However, I am having some trouble figuring ...
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ST7735 driver IC connection with TFT DISPLAY
I am a noob to electronics and thinking of using this 128x160 1.8 inch Color TFT LCD Display with ST7735 Controller SPI in my project. So, does the TFT Display come with a pre-programmed ST7735 ...
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What are these double arrows on a schematic?
If I have to reproduce this schematic in KiCad, what should I use?
How do I represent Vin+ in KiCad? Is this a local or global label?
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Schematics IC a / b / c suffix meaning
On the schematics below, I try to understand what does IC1b or IC1d mean. Could you help me to understand it?
Image source: Making Easy Circuits - Electronic Dice Circuit
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ATMEGA32U4-AU Schematics Sanity Check
I had previously asked a few questions about ATMEGA32U2 and got great feedback. I updated my schematics and went ahead to order, only to realize that JLCPCB is currently out of ATMEGA32U2. I have ...
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What went wrong in my reverse engineering?
I am reverse engineering a toaster.
I have the following part of the circuit that I don't understand.
Let me explain what I have at the moment:
We have a potential difference of around 20V DC coming ...
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