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.

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3answers
96 views

Component with multiple VCC and GND pins. Should I connect all of them? [duplicate]

I want to make a really small arduino using the Atmega 328p and I noticed that it has 3 GND pins and 2 VCC pins. I measured the pins and it seems that all GNDs are connected and all VCCs are ...
0
votes
0answers
18 views

How to Simulate 10w LED packages in Circuit Lab

I've been messing around buying random electrical components from China and I came across these 10w LEDs and, after seeing how bright just one was when supplied with 12v at 900mA, now I'm looking for ...
19
votes
4answers
2k views

What is the use of an op-amp whose output and inverting input are connected to ground?

I am in first year of Engineering school and I was given an assignment containing this circuit, which drives pressure sensors in a pitot tube : I am struggling to understand the whole circuit, and ...
2
votes
1answer
109 views

What is this symbol?

I am in first year of Engineering school and I was given an assignment which contains this circuit which drives pressure sensors in a pitot tube : For training, I am trying to reproduce it using ...
3
votes
1answer
21 views

Altium: Change Net Label Size and Font at once!

I have a complete schematic project in Altium Designer. I need to change Net labels text and font. Since I have a huge number of Net Labels, I am wondering if it possible select for instance 20 ...
1
vote
1answer
42 views

Measuring DC current with Hall Effect sensor over PIC on the same circuit

Before I begin with my question just so you know I'm not very familiar with electrical engineering so please forgive if I ask some dumb question :) What I want is to know if I can use Hall Effect ...
1
vote
1answer
36 views

Altium warning: Adding items to hidden net +3.3V

I am drawing a schematic project in PCB Designer and facing the following warnings when I compile the project: Adding items to hidden net +3.3V and Adding items to hidden net Ground When I double ...
-2
votes
1answer
90 views

What kind of this electrical schematic? [closed]

I have to re-draw this schematic by Office Visio but don't know what kind of this schematic is, and how to find these components in Office Visio.
0
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0answers
27 views

Amplifier Schematic Question

I have acquired two Hitachi ss-81A (not my post, but same speaker model) and I want to build an amplifier for them. They are 8 ohm, 4 watt max speakers. From my research so far, it seems like the ...
-2
votes
1answer
63 views

Help choosing component values for a relay delay circuit

I want to build a circuit that controls a relay with the following specifications: the relay should turn on and stay on for ~60 seconds after the button is pushed the relay should stay on as long as ...
0
votes
1answer
26 views

How to remove pin name from Eagle Device Page? [See Image]

How to remove those pin name from Eagle Device Page?
3
votes
1answer
38 views

Is my Bob Smith termination valid for Ethernet 100Mb/s?

This is my first ethernet circuit, and I am a noob in differential signal lines. That is why I want to learn with a "simple" circuit. I use the reference schematics from the LAN9512 usb to ethernet ...
0
votes
1answer
19 views

Schematic representation for net connected to specific component

I have a board with a +5V trace from a current sense resistor across a noisy +5V plane to an OpAmp, so I thought I'd shave that particular yak soon and create a few symbols for KiCad that actually ...
1
vote
2answers
86 views

GND in a DC circuit with circuit board

I wonder a question. Let's say I use a circuit board in a project (the left hand side on image below, not the Verabod), and I want to solder a circuit on it. For example, I want to use the circuit ...
0
votes
0answers
17 views

LCD interface and contrast adjustment scheme

I am referring below graphical LCD. But since it's datasheet is not thorough, I have few queries in interfacing. Interfacing: VDD,LEDA is 5V and VSS is Ground. How Vo,Vout connection is to ...
2
votes
4answers
121 views

Difference Between - (Minus Sign) and Chassis Ground in Schematics

I was working on building some projects from the book Electronic Projects for Musicians and I noticed that in most of the schematics there are two symbols for what seems to be ground. One is a - ...
3
votes
3answers
144 views

Altium Schematics: what does Locked function mean?

I am drawing a schematics in Altium Designer and faced this function when I double click on the components. I need to know when there is a component with different parts, ex: 4 parts. I have to assign ...
1
vote
1answer
87 views

Xbox one power adapter wiring - converting it to a 12 volt power supply

Thanks for having a look at my question. I know this may seem like an odd question but here is the history of it. I have a Solidoodle 4 3D printer, Its powered by a knock off xbox 360 brick adapter ...
0
votes
4answers
120 views

Possible error in schematic; unrealistic capacitor

I am trying to get the parts for this electromagnetic coilgun, and I have gotten almost all of the parts. I cannot seem to find the 1,000 uF 1.5KV capacitors (C3 and C4) for the voltage ladder, and ...
0
votes
1answer
84 views

Chess-Board schematic/pcb layout

Hey guys as described here I also want to make a chess board with some arduino support. Here I want to ask some questions regarding the schematic and the pcb layout I am planing to do. @Dmitry ...
3
votes
1answer
44 views

Altium error: Net contains multiple output sheet entries

I'm having a hard with this one and cannot figure out how to deal with it. As shown in the figure below, ADC[0..2] is going out from A2 and A3 and in to A1: In details: ADC 0 is the output of ...
1
vote
1answer
35 views

Altium Designer: How to handle these type of Nets?

I have such complicated Bus [0..4], which go out from Page 2 to Page 1, and then from Page 1 to Page 3 as shown in the figure below which is a Top Sheet: I receive the following error when I ...
0
votes
0answers
24 views

230 VAC signal with spark capacitor should work on a high-impedance sensor

Preface There are lot of a motion sensors which turns on L (phase) on its output. In my case I need to connect this output to my board to 'sense' the motion. To do this I put 1 MOhm resistor between ...
2
votes
1answer
106 views

Why do these triangle symbols mean?

In configuration B in the image below, what do the triangles mean?
3
votes
2answers
333 views

Altium deisgner: drawing 4x10k resistor

I am drawing a schematics in Altium Designer. Based on an old design, there is 4*10k resistor as shown in the figure below. It is actually one component (one Part No in the library) with 4 different ...
0
votes
1answer
32 views

Upper and lower dimmensions in schematics [duplicate]

What is the difference between upper and lower dimmensions in schematics? So far I have assumed that those are simply maximum and minimum values specified by the tolerance. Is my assumption correct? ...
5
votes
1answer
798 views

Meaning of “caps not pop with watch crystal” in a schematic

caps not pop with watch crystal You can find this sentence in ADuC 841 evaluation board schematic. Could someone explain what does it mean?
0
votes
1answer
87 views

Altium: Unconnected port “xxx” at 550,430

As a new in Altium and trying compile my PCB project. I got a warning which says: Unconnected port "xxx" at 550,430 It seems really strange since I see a normal port which is connected to a BUS at ...
6
votes
4answers
238 views

Minimum energy required for LED blink to be visible

I have a 5V schematic with 15n capacitor and I wondering if I will be able to blink an LED, powered from this capacitor. My calculations is that the capacitor will have about 0.2 uJ of energy. This I ...
2
votes
2answers
87 views

Altium error: Open emitter pin and power pin object!

I am new with Altium Designer. I receive the following error: (+12V contains Open emitter pin and power pin object!) Here is the error schematic part: The error is in Pin 4. Any TIPS?
1
vote
1answer
55 views

How to debug combinational loop warning in Xilinx ISE

I am designing a Binary to BCD converter logic circuit for implementation on Xilinx Spartan 6 FPGA's, and I have a warning during synthesis that looks like this : ...
0
votes
0answers
64 views

altium: where to find a generic logic gates ICs?

I'm looking to add a few generic logic gates to a schematic in Altium. Where can I find the components? I don't need to simulate the circuit and I don't need a PCB footprint - just the schematic ...
17
votes
5answers
3k views

What does “Piggy” mean in this Schematic?

What does the word "Piggy" mean in this schematic diagram? I found some sections of a schematic where a part is denoted as "Piggy". What does it mean?
0
votes
1answer
49 views

12V peristaltic pump flow control

I have 12V peristaltic pump and need to control its flow (lowering down more specifically) Two options I came across: POT in series Voltage divider Is there any shortcomings in above schemes? ...
1
vote
1answer
39 views

Assigning numbers to the new components in Altium designer?

I am drawing a schematics in Altium designer. I have several schematics (sheets) in my current project. Some of the components have already a designator numbers like R5, C20, L13 ... etc. But some ...
0
votes
1answer
48 views

Project libraries don't show in Altium 14.1

I am having strange issue, because when I open my schematic document and try to add component, when I click on Libraries (it doesn't show my project libraries). Libraries. I try to edit in ...
0
votes
0answers
45 views

Suggestion proofread my atmega with nrf24l01 board

I am making a revision to my mini LED display board. Other than asking for help to see if there are any faults/suggestions on this circuit. I also have few questions: I am using a 1w 0.1 ohm ...
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votes
1answer
90 views

is there a way to light up the second led and not the first one? [closed]

simulate this circuit – Schematic created using CircuitLab In this schematic I made I'm trying to light up a a series of LED's but not in sequence "not yet" what I want is to raise the ...
0
votes
2answers
66 views

7.2VDC and 6VDC power supply from 12V transformer

I have a Arduino MEGA2560 clone, 5pcs of standard size servo motor (model MG996R) and 2 pcs of micro sized servo motors (model 9G), which I have to supply with DC power. And because the micro Servo 9G ...
0
votes
1answer
71 views

Decoupling Capacitor Calculation

I have few questions related to the schematics(BBB_SCH) sheet 2 in link There is a bulk decoupling capacitor of 10uF,10V connected to the pin ...
0
votes
1answer
57 views

Conceptual question on interpreting magnitude graphs

I am designing a band pass filter and I am having trouble understanding how to interpret my simulation results. What I think this is telling me is that when I send a frequency through one of my ...
0
votes
1answer
85 views

Schematic Check for Color Organ

I am making a small color organ just for proof of concept fun. I am using 3 passive low, band, and high pass filters with their outputs connected to an envelope detector and a BJT that drives each ...
-3
votes
1answer
144 views

Laptop Motherboard Schematics [closed]

I am working on a bunch of Hp laptop motherboards. These models are variations of HP 15-f Models They have different model numbers but the boards PCB looks the same just different variations of the ...
0
votes
2answers
203 views

Can I connect many SX1272 (LoRa) based devices to a gateway?

Simple question: Is SX1272 chip by Semtech capable of sending data to LoRa gateways? I'm a little bit confused about LoRa and LoRaWAN. What is the difference?
6
votes
2answers
91 views

Capacitor value in schematic with “mk” units

I've got a schematic that originated in Brazil that generally uses European symbols rather then US. But some values for capacitors are confusing me. There are several that are marked 100n and so ...
0
votes
1answer
53 views

how to remove this error “ERROR 152: Port on instance does not exist in entity declaration for instance”?

I am new to Cadence Allegro HDL for schematic design and for my first design i got this error. In 728 page document provided by cadence its is mention as follows, "Open the symbol for the component in ...
3
votes
2answers
78 views

Proper Arrow Directions for Off Page Connectors / Symbols…

Good day everyone, As I understand it, there are two kinds of objects that can be used on a schematic to indicate that the Net to which they are attached is connected to a location elsewhere on the ...
-7
votes
2answers
99 views

Creating electronic parts from scratch [closed]

So I want to create my own electronic parts from scratch,I don't like buying stuff from internet because it's mostly expensive and I believe if you make it yourself its more cheaper. You might ask ...
3
votes
1answer
65 views

How to represent socketed components in schematic

What method do people generally use to represent socketed components in a schematic, notably in this case I am referring to resistors & capacitors mounted into machined socket pins (multiple into ...
1
vote
1answer
155 views

SX1272 - LoRa - What is the minimal schematic (needed capacitors/resistors) to use that device?

I'm interested in SX1272 by Semtech. It's a LoRa modem. I'm not the best at reading datasheets. Maybe it's because of my poor English. I wonder what is the minimum schematic of such a chip? What ...