Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [level-shifting]

Level shifting is the process of converting between different voltage ranges or logic levels, e.g. from [-1 - 1 V] to [0 - 3 V], or 3.3 V logic to 5 V logic.

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Step up 3.3V to 5V for digital I/O

I normally use an Arduino for my projects because it has 5V inputs and outputs and has 5V Vin so that makes life very easy when interfacing with 5V components. For this project I want to use a Raspberry Pi because I want to hook it up to a display.…
Huckle
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Bidirectional 5 V to 3.3 V level shifter

How do I interface 3.3 V Input/Output to 5 V Output/Input? I need it primarily for an Arduino Due but any general purpose bidirectional circuit (or IC) would work. Some people advised me to use the SN74AHC125 and CD4050 ICs, but I don't understand…
3bdalla
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Can I reduce voltage from 3.3V to 1.8V using a 1.5V battery?

I am interfacing to an EEPROM that works via SPI at 1.8V; unfortunately I do not have a 1.8V power source around and being this a weekend project, I wanted to complete it without going to the shop. I asked a skilled friend an advice and he suggested…
gdm85
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Single transistor level up shifter

I need a simple, single directionnal level shifter for 3.3V -> 5V conversion. There are many options on the internet, some using a logic ic and some using 2 NPN transistors (converter and inverter), but I never found an option using only a single…
Nicolas D
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Level shifting a +/- 2.5V signal to 0 - 5V

I have a front end module that generates an (ECG) signal that varies from +/-2.5 V. I want to shift this signal to 0 - 5V. What is the best way to do this? Would a summing amplifier like the below circuit good enough? With R1 = R2 and V1 = 2.5V, V2…
govind m
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Is my MOSFET-based bidirectional level shifter insane?

In a moment of cheapness, I decided not to order a 5v to 3.3v level shifter from Sparkfun, but instead to put it together myself. The original schematic used a BSS138 MOSFET, but since I enjoy surface-mount soldering about as much as root canal…
Jon Bright
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I2C: 3.3 V and 5 V devices without level-shifting on 3.3 V bus?

Do I really need a level-shifter if I use 5 V-powered devices on an I2C-bus that has pull-ups to 3.3 V? In my understanding the devices will only pull the lines (SDA, SCL) low (to ground) and never drive their supply-voltage to the bus. So I don't…
Jannis
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Are BJTs suitable for level-shifters? It seems FETs are more common,how do they compare?

I'm a hobbyist, and never got past the datasheets/tutorials for FET transistors; I'm a BJT man. I never found discussions dealing with BJT vs. FET and specific applications best suited for each type. My projects are very simple switching and logic…
user160409
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Shutdown Controller for Raspberry Pi in a car

Following on from my previous question I'm trying to create a shutdown controller for my Raspberry Pi. The Raspberry Pi needs to be powered from the battery, but should power-down after the Pi detects that the ignition has been turned off. The Pi…
Nicholas Albion
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How is this circuit for level converting (5V<>3.3V) working?

Does anybody know, how is this circuit exactly working? It is level converter between 5V and 3.3V logic and it is bi-directional. I have some theory, but I am not sure with it (I never worked with MOSFET before). And what is that diode for? I take…
vasco
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I2C level shifting

I am currently designing a circuit that can record data from a sensor and save the data recorded into an EEPROM. My two devices (EEPROM and for testing purpose a RTC) are connected via an I2C bus to a PIC16F887 µC. However, the two devices voltage…
Al_th
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Analog voltage level conversion (level shift)

I have a joystick that puts out analog voltage somewhere between 1.5V and 3.5V. I want to transform this range of voltage to control a motor controller that takes analog voltage between 0V and 5V. How do I level shift and amplify properly?
jfenwick
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How do you shift a square wave down?

I have a square wave the oscilates at 25khz from 0 to 30v. I would like it to oscillate from -15v to +15v. Is there a SUPER DUPER SIMPLE circuit to do this? Keep in mind it's going up and down at 25khz. Here's the circuit. The square wave I want…
Curtis
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How to convert a digital signal from 24V to 5V

I have an industrial automaton that gives me a digital signal (24V or 0V) on its outputs and I want this signal to control an integrated circuit, but the integrated circuit only takes a TTL signal in its input (0 to 5V). I think it can be controlled…
Pierre B
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What's the purpose of this diode in this level-shifter?

look at this circuit: I don't get that what's the usage/purpose of the BAS316 in this circuit?
Roh
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