Questions tagged [5v]
Questions regarding 5V level signals, level-shifting, and circuits.
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2answers
79 views
How to efficiently trigger QC and convert it to constant 5V and a peak of 5A?
Introduction
For a university project I started working on RGB LED Shutter glasses, which are based on the idea of a kickstarter by Macetech. However, these glasses miss some features I was looking ...
1
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1answer
49 views
PIR Sensor for bulb in room
This has been very long since I left electronics but recently I restarted taking interest in it as hobby.
I bought some PIR sensors from Aliexpress and found it is very simple to implement if I have ...
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3answers
68 views
DC 3-12V Water pump connected to power source doesn't work
I'm trying to make a simple connection of 3-12V Water Pump to a power supply(https://www.amazon.co.uk/dp/B07D3XS91J?ref_=pe_1365641_54848841).
I'm using power supply which is 5V (https://www.amazon....
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1answer
46 views
SOPs for converting a digital circuit from 5V to 3.3V
I am in the middle of an exercise in which I have to upgrade an old motor driver circuit. The old circuit has an MCU and all its logic based on Vdd=5V. I have to use a new MCU whose Vdd=3.3V. So now I ...
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3answers
99 views
Interfacing GPIO 3.3V to 74HC04 5V
Will it be safe if I connect STM32F407 GPIO outputs (Vdd=3.3V) to 74HC04 hex Inverter inputs (Vdd=5V)? What is the best recommended method to add an inverter at the output of STM32F407 MCU?
edit:
...
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2answers
81 views
The Blue LED of ESP8266 glows continuously when connected to 5V relay output
I am a newbie. Need help on my project.
I am building a project which controls a 5V relay from ESP8266 ESP-01. Since the GPIO2 gives the output of 3.3V, I am using an N channel MOSFET 2N7000 to ...
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2answers
37 views
Isolated DC/DC converter application circuit / usage
I'm trying to find a basic application circuit schematic for an isolated DC/DC converter – this one specifically: DCWN03E-12 – but I'm having no luck so far. The thing that led me to this particular ...
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1answer
57 views
Measuring USB power adapter quality using multimeter
I have heard horror stories about poor quality USB power adapter. I have a collection of no less than 20 USB power adapters, most are from cell phone manufacturers and some from small projects.
I ...
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1answer
47 views
si7021 with 5V MCU [duplicate]
i need to connect Si7021 wich is an 3.3v I2C humidity sensor with Arduino,
this sensor has open drain SCL and SDA drivers.
is it possible to connect this sensor directly to Arduino 5V?.
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votes
1answer
60 views
Feeding AMS1117-5V with 3.3V [closed]
I need that an Arduino NANO clone work with 3.3V.
Can an AMS1117-5V give 3.3V if supplied with only 3.3V?
edit: current consumption is 400mA max. the AMS1117 output current is 800mA.
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1answer
85 views
Are there 5V battery packs available without a boost converter? [closed]
Looking for a 5V portable power source without switching or conversion noise.
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0answers
33 views
Switch resistor with n-channel MOSFET not working
So I try to amplify a photodiode signal with an operational amplifier.
As I want to amplify two signals (1 for a high-intensity light and 1 for a low-intensity light) I sort of need to design a ...
0
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3answers
96 views
Correct use of op-amp to amplify photodiode in reverse bias
So I have a photodiode in reverse bias, from which I intend to measure my pulse.
Currently, my schematic looks as follows:
simulate this circuit – Schematic created using CircuitLab
Weirdly,...
2
votes
4answers
520 views
Photodiode almost no mV at analog port
So I have bought a photodiode, which I intend to hook up to the analog port of my Arduino, so that I can measure differences in the light that the photodiode picks up.
I realized, that when I don't ...
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1answer
39 views
where do i find max short circuit current of photodiode?
I'm trying to convert the current signal from a photodiode to voltage through a transimpedence amplifier.
The photodiode is put in photovoltaic mode in order to get the greatest accuracy and lowest ...
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1answer
107 views
Why is this photodiode operated in reverse bias
Referring to the following document by NXP on figure 9. The cathode of a given photodiode is connected to the transimpedance amplifier in forward bias.
To me, this seems wrong, as almost every ...
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1answer
73 views
Choosing the right capacitors and resistors for transimpedance circuit
I'm designing a circuit for a pulse watch. Therefore I naturally have an operational amplifier and a photodiode in my circuit.
The job that I want the transimpedance amplifier to carry out is to ...
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1answer
90 views
Correct use of transimpedance amp
So I realized that it might become a necessity for me to use a transimpedance amplifier for a pulse watch that I intend to make.
Some background:
The pulse watch shoots light at 940 and 660nm at ...
0
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1answer
57 views
Does this photodiode need an operational amplifier?
I'm trying to make a circuit for a pulse watch, which should be capable of measuring blood SpO2. I use 2 LEDs for each wavelength (respectively 660nm and 940nm) to shine at the upper wrist.
The ...
0
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1answer
120 views
5V to 3.3V for bluetooth module - Is a voltage divider ok?
So I purchased the JDY-10 BLE 4.0 module and a very small MCU which only is capable of feeding 5v.
Since I'm not an electrical engineer, I've been reading a bit on the internet, and so far, I ...
3
votes
1answer
127 views
Powering 9216 leds @5V, @24V with converters
I am struggling with a power supply question. I would like to power up and control 9216 LEDs -- strips of 144 LEDs/meter (WWA SK6812 - just like the RGB kind).
These are powered at 5V and draw 43.2 ...
1
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1answer
43 views
Driving power + USB over cartridge connector [closed]
I hack old hardware (mostly microcomputers) by putting new insides in them, but I still consider myself a newbie when it comes to electrical engineering, so please bear with me, because this question ...
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2answers
188 views
2.8V to 5V conversion not working as it should. Why?
I'm using an arduino Leonardo clone (SS Micro) who works on 5V logic only, but has also a 3.3V output for powering devices.
I'm interfacing it with a breakout board TOF sensor, the VL6180. This ...
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2answers
103 views
Tachometer Signal Voltage Reduction
I am working on a formula style car and creating a digital dash based on an Arduino. I currently have a signal from the ECU running at 12v DC and a varied frequency depending on the RPM of the engine. ...
3
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2answers
895 views
Having trouble in GPIO output, 220 V to 5 V signal
I'm not an electric guy, I'm just trying to build a small circuit to sense 220 V with my Microcontroller (RPi). But I'm getting either 5 V or 1.3 V on a GPIO wire.
I can't understand the problem. I ...
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1answer
178 views
Two 5V Raspberry Pi UPS Idea
I need a cheap, reliable and easy to build UPS for my raspberry pi server.
The UPS must maintain power for a maximum of 1 hour.
Based on what I found on the internet,I came with two solution. (see ...
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3answers
114 views
I'm planning to put lots of phone chargers on one circuit, how to calculate this
This would be primarily for samsung S7 devices. Would like to be able to charge, say, 256 of them.
They will work in groups of 16, trying to design the power flow of this. Was imagining that each ...
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3answers
279 views
True 5V CPLD other than PIC/Altera ATF150*?
Are there any True 5V CPLD's families still in manufacturing other than PIC/Atmel ATF150*?
I am talking not just "5V tolerant IO", but rather ones with 5V VCCIO, able to drive 5V loads without ...
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3answers
121 views
Can a 12V power supply provide more than the rated current at lower voltages?
This might be a silly question but if I'm using a 12V power supply rated to provide 5A does that mean that if I was to regulate the voltage down to 5V I could theoretically draw 12A at 5V?
If Watt = ...
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1answer
165 views
How to reduce noise in this circuit?
I'm using a Raspberry Pi in a circuit I'm building that includes a few elements.
Elements in the circuit:
PWM driver to control 3 servos
Mic board for recording
Class D Amplifier that drives 2x3W ...
1
vote
1answer
139 views
micro blown up with 3V?
I'm attempting to make a 12v blinking light that turns off with a high signal and since I've got some 5v arduino pro minis I though I might do it with them. So I put together a program and a plan
My ...
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3answers
145 views
OpAmp VS Voltage Divider VS Buck Converter (Current Sensor Output)
I'm working on part of a project and I need to build the circuit that reads the current through a phase of a motor using this IC from Allegro.
Assuming there will be no more than 5A, and using a VCC=...
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0answers
94 views
Delay +5V to LED strip from 30A power supply
I have an LED project I'm working on using addressable LEDs (WS2812B). I'm powering these 900 LEDs with three 5V, 30A power supplies (one PS/LED strip).
The issue I'm finding is that when I switch on ...
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1answer
61 views
REF02 not working - 4 channel 5v DAC circuit, star gnd connection, stripboard layout
I've connected my circuit as in the diagram, with a 15V PSU powering it (both amps are connected the same way) - but the DAC seems to be drawing too much current for the REF02 to handle, even though p....
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4answers
631 views
5s backup by 1F 5.5V Super Capacitor
Can I have about 4 to 5 seconds backup by 1F 5.5V Super Capacitor?
Power supply output voltage: 5v 600mA
I need 5v 0.5A for my system.
I want to use it as ups for only 4 to 5 seconds so I wasn't ...
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0answers
67 views
Varying performance of mbed, depending on Power Supply
I've written a very basic program (without the mbed library) to turn on all LEDs on an mbed board (https://os.mbed.com/platforms/mbed-LPC1768/):
...
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1answer
106 views
How does this circuit works ? Usart level shift
I'd like to ask how does this circuit works:
I understand how it works in principle, but not technically. It's a USART voltage level shifter. It's supposed to divide 5V to 3.3V by a resistor divider, ...
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1answer
222 views
Can I use a twisted pair for 5V and ground?
I'm going to use a RS485 modbus connection which requires a twisted pair. Now I also need power, that will be a 5V line and a ground. The distance will be about 3 meters max. Can i use a twisted pair ...
0
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1answer
161 views
Splitting a +5V rail into 2 isolated +5V lines
I have a 5v 10A power supply that I am using to power my project. The project consists of a raspberry pi and 3 servos that are controlled by the pi through a PWM driver. The 3 servos and the Pi are ...
0
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0answers
74 views
Designing a Lipo Charger for 1 or 2A charge, 5A discharge
I'm looking for/designing a Lipo charger which can handle a discharging current of 5A at 5V.
Obviously, the lipo's charge is 3.7V (max 4.2V, min 3.2V), so most charging circuits inside a power bank, ...
0
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1answer
2k views
Vcc and gnd in microcontroller on proteus
The microcontroller power pins (Vcc,gnd) in the proteus are set to 5 volts by default. I have basic regulator circuit (my vcc 3.3 volt). How can I use my circuit for microcontroller power supply?
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3answers
98 views
Dividing Current to 10 outputs from 5V source
I need to create a simple power supply circuit to feed 10 external boards, similar to a USB power hub.
My power source is an AC to DC adapter measured to output 5V 10A. I need to limit the maximum ...
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1answer
94 views
Load cell amplifier inverse voltage output
I'm making a load cell modification to my Logitech G29 brake pedal.
The potentiometer on the existing pedal have inverse voltage so 5V is no brake applied and 0V is max brake applied.
This is inverse ...
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1answer
148 views
Voltage oscillates continously in USB Li-ion charger. Anomaly or CC/CV behavior?
I have purchased two USB boards for charging Li-ion batteries and it should have a CC/CV charging regime. So I connected the board to a 5V USB source (computer first then solar panel) and the voltage ...
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2answers
325 views
Can i switch npn transistor using 12v
I want to switch on 5V when switch is connected to 12V. I have been using relay to do this, but I am wondering if I can use NPN transistor or something similar that is cheaper and smaller than a relay....
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0answers
156 views
Help Identifying this circuit and understanding how it works
So I'm hoping to make a few modifications to my Computer case and have found that a number of the LED elements have an associated circuit to them.
I want to be able to understand what I'm doing and ...
0
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2answers
285 views
Replacing the relay in my circuit
I have this delay circuit. I am trying to delay the power to R1(which will be an android phone) by 1 second. SW10 is my SPST relay. Can i replace the relay with something cheaper and physically ...
0
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1answer
40 views
rc circuit for delay to charge android phone
I have made this circuit such that once switched on it takes about 7 seconds to get to 5Vs. I want to connect my phone to it (replace voltmeter in circuit with phone). Without the phone being ...
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0answers
180 views
Need smallest way to achieve 5v portable battery
I have attached two images - One showing the rechargeable USB board I would like to use - The other showing two 3V batteries that have the rechargeable USB already attached and my question is can I ...
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0answers
43 views
Can you identify what type of dc jack component is this?
The little pins that connect to the motherboard broke and i need to find a replacement but i can't find a replacement.
