Questions tagged [component-selection]
All related to methods to select the correct components and/or component values to specific applications
354
questions
2
votes
1answer
36 views
Component footprint symbol cross-reference / cheat sheet / appnote?
While shopping for components I've noticed different manufacturers / suppliers will use different names / codes for identical footprints, which can make it a chore to work out what will actually fit - ...
0
votes
1answer
64 views
Best way to "cut" a connection on a pcb [closed]
Imagine you have some traces on a PCB, that connect from point A to point B.
I would like to have control over that connection. I want to be able to enable/disable the connection from a distance (...
-1
votes
0answers
50 views
Clamping for external reed/contact sensor
i'm trying to realize a low power input interface for reed/contact sensors for my MCU (ATMEGA328P), i've seen the Trevor_G answer to this question and i think that this will be the way to go, using ...
0
votes
1answer
84 views
How can I produce a continuous sound of pressure 70 dB with randomized noise? [closed]
How can I achieve a sound system that can produce a continuous sound with randomized noise in the range 70-75 dB?
I need that for conducting a medical experiment in which the doctor measures stress ...
2
votes
1answer
61 views
How to catch signal in ESP8266 when someone rings (doorbell)
I'm actually a software developer and new to electronics and ESP8266 etc.
I want to learn electronics and my first project would be to catch the signal within ESP8266 when someone rings / uses the ...
1
vote
2answers
70 views
Relay selection for 48V loads
I want to use a relay to remotely switch a 48VDC 1A load (3A peak on startup with capacitive load), however, nearly all relays I have looked at specify a 30VDC maximum contact voltage. When searching ...
0
votes
1answer
37 views
Determining component design age
Is there a way to see when a component was designed without opening every datasheet?
I look at some TI LED driver parts first released 2007, revised 2016. Is that datasheet or component?
Does it ...
2
votes
0answers
50 views
How to choose the right flexible cable for moving parts?
Is there a generally accepted guide to select a cable, which has to withstand certain bending stress?
I am looking for something like this:
...
0
votes
1answer
69 views
DS3231 Question
Can someone help me understand the differences between:
"Adafruit DS3231 Precision RTC Breakout" and one of these generic breakout modules, "DS3231 AT24C32 IIC RTC Module"?
Why I ...
2
votes
1answer
59 views
How to choose a common mode choke for ethernet?
I'm currently working on a design which contains gigabit ethernet. Due to some weird size constraints, I can't use a magjack or one of those transformer ICs, so I'm using discrete magnetics. I've ...
0
votes
2answers
50 views
Which (if any) capacitors should I choose for these DC/DC converters?
I’m trying to choose/work out if I need capacitors for the input and output of two DC/DC converters.
The first converter is a Murata PAE-29/3-D48, powering this along a ~30cm cable, and a bike ...
2
votes
2answers
360 views
Normally open pushbutton that remains closed until fully released [closed]
Description of desired item
I'm looking for a button component that is normally open, stays open while pushing it, closes when the maximum travel distance is reached, and then stays closed until fully ...
6
votes
4answers
1k views
In terms of costs of mass production: is it better to try to reduce resistances' tolerance or capacitors' tolerance?
So I am doing a small project of optimization of components tolerance to reduce the impact of circuit sensitivity to meet a project specification.
Right now I am with 5% resistors and inductors and 3% ...
1
vote
1answer
50 views
Power ORing with power switch with reverse current prevention
Power ORing is usually done with diodes so that the power source with higher voltage is powering the load. Can these diodes be replaced by power switches such as SiP32508 that doesn't have output ...
0
votes
0answers
35 views
Replacement DAC for MCP4922
I have designed a circuit for controlling a device in the lab, using a Microchip PIC32MX Microcontroller, connecting via SPI to a pair MCP4922 DAC, the output is then adjusted with an operational ...
1
vote
1answer
189 views
How do I stop buck converter voltage from dropping whenever current increases?
I built this buck converter circuit using the LM2596T-5 (5 V OUTPUT, 12 V INPUT) using the exact components mentioned in the datasheet's first page (schematic below), except for the diode.
I used the ...
1
vote
2answers
154 views
Selection of MOSFET for flyback transformer switching circuit
I am working on a project that uses a transformer in flyback mode to create plasma arcing. It's based on a simple circuit that's available in a lot of DIY kits which uses a MOSFET to switch voltage on ...
0
votes
1answer
50 views
What is wrong/missing from the process subsystem? [closed]
My teacher told me to reconsider the process subsystem but I'm not sure what is really missing from it.
background story: when a guy is standing on the porch, the LED lights up
0
votes
0answers
71 views
Convert a through-hole type circuit board to SMD type
I want to replace the through hole parts of the following circuit with SMD parts (control section.) This is an 80W FPC using L6562A. Is this a straightforward action or does it require further ...
2
votes
2answers
74 views
IC for ultra-low power switching
I've previously used complimentary pairs (eg DMC2990UDJ) to switch ICs on and off.
I've attached a schematic which switches a potential divider for battery voltage monitor as an example. Where R7 and ...
-1
votes
3answers
168 views
What is a suitable equivalent to 2N5459 JFET? [closed]
I am attempting to build an audio limiter circuit which has a JFET as part of the BOM. This JFET is obsolete and no longer manufacturered. Can someone recommend an equivalent JFET or a way of ...
0
votes
3answers
309 views
For the capacitor specification "Ripple Current at Low Frequency" is a higher value better for a linear power supply?
I'm finding information that seems to be contradictory in various places, and I think people are talking about different ways of looking at the same spec.
The specification that Digikey uses to search/...
0
votes
1answer
125 views
What DC motor is suitable to push and pull 60 kg load system with wheels?
I have a projector system with a PS4 and other electronic devices that I put on a small shelf cabinet with wheels. In normal status it will stay inside the space under my wardrobe. When I need to use ...
0
votes
1answer
149 views
Is there any reason to use the LM317 in place of the better and more recent LM338?
This more recent version of the LM317 is fantastic, and while it happened some of my LM317s "fried" somehow, LM338s never betrayed me.
Reading the datasheets, I don't find any advantage to ...
-1
votes
1answer
61 views
Choose a varistor for a broken PC PSU [closed]
My computer's PSU (Corsair RM 650X) has blown.
I've searched a bit online and I have found that this is a common defect due to a low quality varistor put in those kind of PSUs before 2018.
I know this ...
0
votes
0answers
16 views
12VDC 3-Position Axial/Rotating Connector
I am looking to source a connector suitable for use in a 12VDC light. I need to assemble/disassemble the 3 components- a base, stem and head.
The 'tricky' part is that I also want these connectors to ...
10
votes
14answers
5k views
Should I take Ohm's law for granted?
I have started recently on the study of electronics.
One of the most basic statements that I learned about electricity is the relationship between the voltage and the current across a conductor. I did ...
0
votes
0answers
18 views
DFROBOT Gravity SEMG sensor component identification
Well, a wire got pulled, and a pin came off.
I have a DFROBOT EMG sensor that has a broken smd component. I need to identify what it is. The picture is shared.
I couldn't find a schematic so from what ...
0
votes
2answers
40 views
Smallest Footprint Source Only (No Sink) Buffer Solution [closed]
I'm currently in the process of designing a cable snake cable tester for recording studios that involves testing for connectivity between a large number of inputs. This involves using a ...
3
votes
2answers
365 views
Why do manufacturers specify typical values, not just maximum and minimum?
Why do manufacturers specify typical values? I am still going to have to design my circuit so that it can accept values within the maximum/minimum values.
What is the probability of getting a "...
0
votes
1answer
91 views
is it OK to replace higher ampere TRIAC for a washing machine?
I have a 6 year old top load washing machine which requires a TRIAC replacement for wash motor. The actual TRIAC that came with factory PCB board is NXP BT138X-800 and the one I am looking to replace ...
0
votes
2answers
153 views
Swimming pool depth sensing
OBJECTIVE: A device that floats on the water's surface and measures the depth. If any changes occur in the depth, it sends a report to a remote receiver.
MY RESEARCH: I have considered the following ...
0
votes
1answer
66 views
Choice of mosfet transistor for linear operation (voltage controlled dummy load / current source)
BACKGROUND
I have built very simple dummy load to test thermal behavior of some switching power supply (5V 5A). Vbat is 8-9V from 6F22 battery. Resistors are oversized to reduce working temperature.
...
0
votes
2answers
28 views
How do I make sure my part matches with the eagle part selected?
I need help matching the part I have with the eagle part.
I'm using a RPX-1.0 data sheet pdf:
https://www.mouser.com/datasheet/2/468/RPX_1_0-1903909.pdf
It is a 3mm by 5mm qfn with 16 pins but it ...
1
vote
1answer
94 views
Why do DC/DC switching controllers seem to favour the buck-boost topology over similar ones like Cuk, SEPIC and Zeta?
I am looking at various DC/DC converter topologies for a power system I am designing. The most suitable topology for me is one that can perform both step-up and step-down functions, so I am looking ...
0
votes
1answer
60 views
Are there smaller packages for Standard rcl (resistor, inductance, capacitor) than 0402mm
I need to miniaturize a PCB as much as possible. Are there packages available on mouser for standard components like resistors (100k) or inductance (Up to 30nH) or Cap (Up to 100pF)?
0
votes
1answer
139 views
How to read Diode Numbering System
How do I read diode numbers. I read that the numbering system for US diodes is the JEDEC system. But I don't think the JEDEC system applies to diode numbers after 1N. Everywhere I look I cant only ...
2
votes
1answer
145 views
Step up 3.3V to 5V to use as power of op-amp
In my previous question I was thinking about how can I "reuse" this circuit (0-10V, 0-20mA and digital contact input), when I only have 3.3V regulated power available from my LoRa Node:
...
0
votes
2answers
103 views
What is the purpose of this thing on NiMH rechargeable batteries ? Can't figure out what this component is or its purpose
What is the purpose of this thing on NiMH rechargeable batteries? I can't figure out what this component is or what it is for.
I'm trying to change the batteries in a Hoover automated vacuum cleaner.
...
1
vote
5answers
1k views
Understanding MOSFET characteristics
I am trying to select an n-channel MOSFET to switch a 12 V power rail. The use case here is to switch on/off a couple of LEDs which are wired in series. The LEDs (datasheet) can draw a maximum of 700 ...
-1
votes
2answers
52 views
How can i make this circuit to switch between two terminals? [closed]
I want to make a circuit so that with a push of a button(hardware one of any kind) i can switch this
to this
Using micro-controllers is also an option just as a passthrough
0
votes
1answer
85 views
How can I reduce the number of microprocessor pins I need to use?
In my circuit, 5 choices are made by the user through jumper.
Please look at the picture:
I have to use 5 pins of microcontroller in this method.
How can I reduce this number of pins?
Is there a ...
0
votes
1answer
59 views
Need help determining if a component is acceptable for use in a production design
For the sake of not going too broad, I am only referring to this single OLED LCD board component from Newegg being used directly within a prototype device that I have designed. My end goal is to take ...
1
vote
2answers
121 views
MOSFET Selection criteria considering conduction losses, switching losses and working frequency
I am trying to choose a suitable MOSFET for my full-bridge resonant converter for wireless power transfer. The circuit topology is something like the following. Specifications: rated power \$-~500 W\$...
0
votes
0answers
60 views
Choose of components for a rgb led strip
I'm pretty new to electronics. I have some basics from my student life but it is not much.
I want to progress in it and the best way for me is to do it with a project.
Anyway, my goal is to power a ...
0
votes
1answer
83 views
How would I build a data acquisition system for SiPMs?
I try to build a radiation detector using of an arrangement of silicon photomultipliers (SiPMs) coupled to a scintillator and I want to read out the number of photons recorded by each SiPM sensor. I ...
0
votes
0answers
53 views
KA336 replacement parts
Can you replace a KA336 with a TL431 directly?
I have a circuit board with a broken KA336 and I can't find it here in my country, not even the LM336. It is a 2.5V shunt regulator.
The adjust pin on ...
2
votes
1answer
66 views
Help Getting Chip Part Number, Logic-Driven DIP 12V/24V Power Control
I am planning a future project, but I need the ability to have a 5V logical high enable a 12 or 24V source from an external supply, in a standard DIP package. I remember using something exactly like ...
0
votes
0answers
45 views
Estimation of Electrolytic Capacitor ESR at SMPS Frequencies
While working on compensation networks or ripple calculations, it helps to know the ESR for my output capacitors. In high voltage SMPS systems, this seems to be difficult for the following reasons:
...
0
votes
2answers
131 views
Voltage Limitations of a header being used as a voltage selector
I have an application that takes a reference voltage. These voltages could be considered 'low voltage' as they range from 0 to 1000 V. Below is a reference schematic of what I'm trying to accomplish, ...
