All Questions
Tagged with level-shifting transistors
24
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Using NPN transistors for I2C level shifting
Background: I'm familiar with the method of level shifting an I2C signal using NMOS FETs and pull-up resistors. The Philips application note AN97055 documents the method and explains how it works here:...
- 21
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2
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Level shifting to lower voltage: logic-gate vs voltage divider
In my design I need to level shift 5V signals to 1.8V, for now I'm planning to use AND gates with the same 5V signal on both inputs and 1.8V as the power source. I got the idea from this document.
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- 490
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1
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244
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Converting 3.3V logic to 5V logic with two common emitter transistors in series
I am working with digital signals. I would like to know if there is any alternative to boosting a 3.3V logic signal to 5V logic only using transistors.
I am currently using two common emitter ...
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3
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2
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Pull-Up Resistor to 5V on 3.3V Output
I'm using a 74LVC245 buffer, which is a 3.3V chip with 5V tolerant inputs. What will happen if one of the chip's outputs is enabled and is connected to an external device with a 2K pull-up resistor to ...
- 308
1
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2
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436
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Improve the response of this circuit
I designed this circuit (shown below) to level shift an input PWM (10 kHz 5% duty) signal (from microcontroller, 0/+3V3) to 0 and -12V. When the input PWM is HIGH (+3V3) the output is at 0V while when ...
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1
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973
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PWM level shift
I have a 10 kHz PWM (0V (LOW) to 3V3 (HIGH)) which I wish to level shift as following; when PWM is high (3V3) the output should be 0V while when PWM is low (0V) the output should be -12V. Ideally this ...
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57
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Bidirectionnal level shifter not working on my clock to drive a smartcard
I'm actually designing a circuit that would permit me to drive a Smartcard, it's a pretty straight forward design :
All the signal starting with CA are coming from GPIO of an IC that controls all the ...
2
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1
answer
319
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Level shiffter (3.3V / 5V) for controlling transistors
Is it possible to control the base of the transistor using the level shift chip (3.3V / 5V)?
I want to use the SN74AHCT125 level shift chip.
Transistor BC337-16
- 535
5
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1
answer
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What's wrong with this single-transistor level-shifter?
I was trying to step up the output of a 3.3V microcontroller pin to 5V for communication with another device. I wanted to do it with a single bjt, and found a good design for doing that here
Single ...
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1
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1
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650
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What's the purpose of using PNP transistors on I2S bus?
What could be the reason of using these 3 PNP transistors on I2S bus (LRCK, BCK and DATA pins)? The DAC used in this schematic is PCM5102. I know for sure that this DAC would work without these ...
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1
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level shifting 5V pulse to 12V pulse
When I search for level shifting 5V pulse to 12V, I came to know about the circuit given below.
It is simply based on a push-pull amplifier configuration as you all know. And what I have understood ...
- 673
0
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3
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5k
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Controlling voltage on source and drain of MOSFET
I learned that MOSFET works by controlling the voltage on the Gate terminal. For NPN MOSFET as an example, when a voltage on the gate is high enough, it lets the current to flow through the MOSFET, ...
- 107
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2
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2k
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Level-Shifter, a resistor i dont understand
I got a lot of help in understanding this circuit in a previous post.
I just don't understand the choice of R3 or why it is even there exactly.
EDIT: I just read my question and realized I give no ...
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Changing a 3.3V signal to a 5V signal using a BJT transistor
I saw someone asking this EE.SE question in a thread over 2 years old and could not really understand some things about the answer.
He had a 3.3V input signal that he wanted to change into 5V signal.
...
- 1,055
0
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1
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223
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at89s52 the right way to drive transistor
I want to ask about this configuration, the port is connected to at89s52 pin (not P0) and some of my friend say that this should work because the at89s52 have internal R that can replace the external ...