Questions tagged [component-selection]
All related to methods to select the correct components and/or component values to specific applications
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Sensor selection for 0.5mm resolution and 0.5m range [closed]
I want to record motion of body of 1 mm2 cross-section made of metal or plastic moving in gas of low density.
I need resolution of 0.5mm (more, as in 0.5-0.1mm, is better) and range of few tens of cm.
...
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Using transceiver between DALI and microcontroller
Does anyone have experience using a transceiver between a microcontroller and DALI bus? Please see the attached wiring diagram. I am not sure what is wrong with the circuit, but when I measure the ...
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Choose right capacitors for flyback design
Would like to build an flyback inverter from 12V to 100V power 250W.
The 12V source is a rectified generator.
I'm struggeling with the right primary capacitor selection.
I calculated a ripple current ...
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How to understand MOSFET "turn on" times?
Consider this circuit:
simulate this circuit – Schematic created using CircuitLab
Ignoring the different threshold voltage, the (time domain) simulation shows a clear difference between Q1 and ...
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Replacement of a MOSFET alternative
This is the MOSFET part that I'm using in the current design - LP0701
Can the NVJS4151P be the right alternative for the LP0701? I am not sure as some parameters do not match.
My requirements :
500 ...
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What can I do about components with inadequate creepage?
I'm designing a device for use in a non-climate-controlled environment (garage, shed, etc.) If I understand it correctly, this puts me directly into pollution group 3 unless I can also engineer it to ...
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(Another) how do I choose an appropriate TVS for a relay?
I've seen questions about selecting TVS diodes before (for example, How to choose the correct TVS diode and how to size it?; there are others, but they aren't about TVSs for protecting relay coils). ...
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Triac dimming using MOC3021 but light is flickering
I m using BTA12/BTA136/BTA139 for dimming using MOC3021 with zero cross detector circuit using interrupt pin of the controller, but after some time light is flickering or triac is damaged.
I m sharing ...
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How to verify if SDRAM alternative is a direct drop in replacement?
I'm trying to verify whether the two SDRAM chips are complete drop in replacements of each other. I've verified the footprint, electrical characteristics and various timing parameters (namely CL, tRCD,...
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High-side switching: Load switch IC vs P-channel MOSFET
I want to switch the power in one part of a circuit with a 3V0 GPIO. The circuit is battery-powered and only active for a short duration once an hour, so I want to use as little power as possible. The ...
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WS2811 MOSFET driver - components help
I'm trying to build a board capable of driving 12 V, single-channel, non-addressable strips with the WS2811 protocol for my project. In my case I want to be able to safely switch up to 5 A (but most ...
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Need advice on LDOs that can take ceramic caps on Vin (8.4 V) and Vout (5 V) at 50 mA of current draw [closed]
I´m designing a really small circuit based on an ATtiny85 and a laser ranger sensor. The PCB is really small, 30 mm by 20 mm, so I need to use smaller and fewer components.
I need a recommendation for ...
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Spring-loaded pins for power transfer
I am trying to build an automated battery swap mechanism for drones.
What I currently have in mind is a battery housing sitting on the drone which has electrical contacts on the inside, and a Li-po ...
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Need an RF switch IC or circuit that can switch with a DC bias
I have an active antenna used for GPS. I need to supply the conductor of the RF cable with 5V DC. It consumes around 20mA. This antenna connects to a PCB where I inject the DC bias onto the RF line ...
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How to approach finding which micro controller include a specific sub-peripheral
Broadly: An application I am working on requires a specific function of a common peripheral. I know that this function is optional in a big family, but short of visiting every single SKU's datasheet, ...
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Switching regulator maximum current - why choose Semtech TS30011 instead of TS30012?
While browsing for a switching voltage regulator, I noticed that Semtech TS30011 and TS30012 have the exact same characteristics and price, only that the former has a max output current of 1A, and the ...
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Help with FBL Z803 chip identification
I have a component on my D5 EVO electric gate motor PCB which was shorting both ends to GND. This resulted in the PCB not powering on.
After removing this component the PCB now powers on, but part of ...
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Help with component choice for weather proof sensor node
I'm planning on making a wireless weather station with a sensor node and a master to display the sensor data. The sensor node would be placed outside and measure temperature, humidity, and air ...
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What op-amp could substitute a TL072?
I'm testing out a VCA audio circuit with parts I have laying around based on this article at skullandcircuits.com.
The design calls for a TL072 (datasheet) which unfortunately I don't have on hand.
I'...
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Help with the Texas Instruments TXS0101 for level shifting
I am considering the TXS0101 for my project, which essentially is multiple I2C sensors paired with an ESP32.
As the I2C for an ESP32 is 3.3V logic and some of my sensors are 5V, a TXS0101 seems to ...
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DIMM RAM package for embedded system
I'm selecting components for an embedded system that requires > 99.5 Mbits of memory with an access bit rate of > 2.99 Gbit/s.
I'm considering using a DIMM RAM module, which should solve both ...
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Computer microphone disconnects when connected to wave generator
I am using the Visual Analyser virtual oscilloscope as both an oscilloscope and a wave generator (on two different computers). I connected audio jacks (1 TRS and 1 TRRS) to a breadboard to connect the ...
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How to select the proper LEDs for light fixture
This light fixture has 3 heads with 15 LEDs for each head. The 3 heads are connected in series. In each head, there are 3 sets of 5 LEDs connected in parallel. The 3 LED sets of 5 for each head are ...
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Differential receiver: 75176 vs optocoupler
I have an incoming differential signal for my PCB to be designed which I have to read.
I also need to isolate the incoming differential signals from my PCB's digital system, so I will be using a dual-...
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Cycling through 3 outputs on clock pulse component choice
Is there a better way to cycle through 3 outputs in a loop on clock input?
I'm currently using a CD4017 with the 4th counter tied back to reset, and this does work well enough.
The fact that it is a ...
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Using different relay for refrigerator’s card
My refrigerator’s electonic card has a panasonic Js1f-b-12v-f relay on it. I need to change it but I only can find panasonic Js1-b-12v-f on the market. When I check the datasheet of both, I saw a ...
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MOSFET choice - PWM LED strip [closed]
I'm looking to PWM an LED strip with an ESP8266 (3.3 V PWM signal) with the following characteristics:
Red channel: 12 V, 300 mA
Green channel: 12 V, 250 mA
Blue channel: 12 V, 250 mA
As I ...
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RC deadtime circuit AND gate selection
I am making a deadtime circuit proposed by Verbal Kint and I ran into an issue where the AND gate I'm using is only giving logic level signals.
Is there an AND gate buffer anyone could recommend to ...
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What is the function of a capacitor between source and gate in this reverse polarity protection circuit?
I want to incorporate a simple reverse polarity protection to my design. I stumbled across this circuit in the Raspberry Pi Compute Module 4 IO Board schematic:
I understand how the Q1 + D4 + R26 ...
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What is this component marked 10mΩJ?
Can someone help me to identify this component marked "10mΩJ?" I'm pretty sure it's a 10 mega ohm resistor, but I can't find it anywhere to buy one. Maybe a similar resistor can work, but ...
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Suitable IC for 3.3 V to 5 V level conversion with a Schmitt trigger input [closed]
I've managed to find some ICs which enable level shifting, but none of them have Schmitt trigger inputs. In order to reduce cost and component count, I'd like to ask some of you experienced designers ...
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What is a field effect rectifier diode (FERD) and what is it used for?
I was searching DigiKey for a particular type of diode, and found field effect rectifier diode (FERD). What are they used for?
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Need advice in repairing my obsolete 44-year-old OEM Ovation acoustic guitar preamp
Preamp (9VDC): 6 capacitors (4 MMKO box film caps and 2 CAPAR axial 4.7uF 50v electrolytic caps), 1 3-pin junction transistor (M2N5458), 2 unknown transformers, 5 resistors. See attached image.
...
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Pure Sine Inverters and Transformer Selection
So I'm trying to design a 24V to 110V pure sine wave inverter, which I'd like to be able to do 2000W to handle running my portable A/C on battery. I get the whole H-Bridge MOSFET concept, and even ...
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How much voltage does a farm electrical fence really output?
My electrical fence control unit says that it outputs "0-miles 13 kV; 3-miles 7.0k; 5-miles 6.0k", yet that doesn't seem right.
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Inductor and Capacitor 3-digit exponent value codes: is there a standard?
I've seen the standard NNX exponential value code where NN are the significant digits and X ...
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Is there a type of transistor (or other semiconductor device) that can do this?
I haven't completely given up yet, on using some kind of semiconductor for the boxed ??? device below, to control an ATX power supply:
simulate this circuit – Schematic created using CircuitLab
...
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What does EE10 or EE15 mean for transformer cores?
I have been studying about transformers. When I went to buy some transformer cores from Alibaba for research, I saw different names like EE 15 transformer.
What does the EE10 or EE15 transformer code ...
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1
answer
637
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Trouble finding LDM for EMI filter
I am trying to use this DC-DC converter and I am having trouble recreating the recommended circuit as I'm not entirely sure what an LDM is or where to find one:
From basic google searches it looks ...
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Type of transformer needed to measure 4-20mA process current?
I occasionally work with 4-20mA process signals and need to read the current value flowing through the wire. I now use a standard Fluke 17B+ and must disconnect the loop and add the meter in series ...
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How do I make sure the replacement switch for a device can handle the power demands?
My 10 year old (out of warranty which ends at 8 years) blender on off switch broke. The unit still runs great, I don't want to trash it. I just need to replace the switch. But I don't know what kind ...
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Choosing a replacement electret microphone
I'm trying to select a suitable replacement electret microphone for an analog (POTS) phone. The existing electret is completely unmarked so I don't know its part number or parameters. I'm not well ...
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Trouble using PNP as a switch
I simulated a circuit as shown below and it works as expected when the switch is closed or opened. I later change the 2n2907 to FMMT591A due to availability, continuous collector current and size. I ...
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DC-link capacitor selection for electric vehicle
I'm currently trying to build a model of a three-phase inverter to be used in electric vehicles. The selection of a film DC-link capacitor is mainly dependent on the allowed voltage ripple, which is ...
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In calculating the inductor for a boost converter, where does the power of the voltage source calculate in?
simulate this circuit – Schematic created using CircuitLab
As I am using LTspice to develop different types of dc-dc boost converter topologies and wanted to define the best inductor to use when ...
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Noob questions about my accelerometer (ADXL345) and Arduino components in general
I've just bought this accelerometer: https://www.amazon.co.uk/XTVTX-ADXL345-Digital-Acceleration-Gravity/dp/B09NRFDH5J/ref=cm_cr_arp_d_pl_foot_top?ie=UTF8
I've bought it to learn about accelerometers ...
user270727
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How do you make a single falling edge pulse when a falling edge is detected?
im designing a circuit where when the switch is open, the 555 timer ic's output goes high but in real life, for the 555 timer to go back to a LOW state, the trigger pin needs to be higher than 1/3 Vcc ...
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3
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How to select IC components by just footprint and low price for Pick-and-Place testing?
I am very familiar with the usual vendors for components, and how to select parts for a design, including package and footprints. However, I'm looking for an efficient way to track down 'throw-away&...
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Low-profile, panel-mount connectors
I'm working on a hobby project, a handwired ultra-low-profile computer keyboard with a 3D-printed case. The USB-C connector on my dev board is only 3mm tall, so it fits within the 4.5~5.0mm of ...
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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 - ...
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