All Questions
Tagged with level-shifting i2c
46
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I2C Level Shifting (Adafruit breakouts)
I have programmed an I2C slave on an Arduino Nano and an I2C master was on an Arduino Mega. I'm now working on upgrading the master to a Teensy 4.1.
The new master is a 3.3v microcontroller, where as ...
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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:...
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I2C Level Translation secondary device battery powered
I'm running a PCF8523 RTC directly on the battery supply that can vary from 3-4.28 V. The RTC must communicate over fast mode I2C with a microcontroller running at 3 V IO.
The RTC VIH is 0.7xVDD = 2....
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IC for translating 5V to 1.8V I2C signals [closed]
Looking for an IC to translate between 5V and 1.8V I2C. I need to connect an I2C sensor with MCU. MCU I2C pins are pulled-up to 5V while the maximum voltage on the sensor's I2C pins is 1.8V.
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Why PCA9306 2.9V coming at lower side even after removing the pullup
Below is my schematic for PC9306. The high side is connected to 5V and it is going to an Arduino Nano.
SDA from our ASIC is coming to J113 (SMA connector marked in RED). The voltage at this side is 2....
- 2,593
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224
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I2C level shifter with only one reference
I need to translate a I2C SCL and SDA signal coming from another board with 3.3V to VDD (1.8V) on my board. So I don't have the possibility to use the 3,3V as a reference voltage. Only the 1.8V.
How ...
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2
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499
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VGA DDC voltage
While designing a pcb with a VGA output, I came across the DDC pins on the connector. I'd like to use that protocol to retrieve data from the monitor.
After searching on the internet, I found that the ...
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Why does a MOSFET level shift on the I2C bus break some I2C devices that operate on the same level as the MCU?
Background:
I'm attempting to control a stepper driver (+5V logic) with an esp32 module (+3V3 logic). The A4988 datasheet claims to operate at +3V3. And indeed it did ... poorly. It works great at +5V....
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1
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259
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Level shifter for interfacing SCD41 and Raspberry pi over I2C
I am connecting an SCD41 CO2 sensor to a Raspberry Pi Zero 2 W. To keep the 3.3V current draw low, I would like to power it at 5V (peak current is 205 mA at 3.3V vs. 137 mA at 5V). A TXS0108E module ...
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Level shifting I2C with VREF1 = 2.8V and VREF2 = 3.3V
I'm trying to connect a few devices on an I2C bus - primarily a GNSS module and a microcontroller. The microcontroller is the bus controller and must run on 3.3V, while the GNSS module internally uses ...
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133
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PCA9306 Level Translator Output is coming without providing Enable Signal
I am using PCA9306 board for level Translation .The schematic is given below.The board is purchased from third party not made by me.(https://www.sparkfun.com/products/15439)
I need to control the ...
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65
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I2C Shifter being used to protect against short to much higher supply rail
For a device I'm retrofitting, there is a risk that some I2C datalines could be shorted to a supply rail that can be between 12-44V, or ground
To the best of my understanding this bodge circuit per ...
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answer
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I2C bus with different voltages slaves
I have one MCU powered with 3.3v acting as an I2C master in the BUS and 4 slaves, one of them is 3.3v logic and the others three are 5v logic.
It's ok if they share the BUS, connecting the 5v devices ...
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2
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Using a voltage divider versus step-down voltage regulator for i2c pull-up
I have a device (NXQ1TXH5) that I want to run at 5V. I am also interfacing this device with a Raspberry Pi4 for i2c communication. This raspberry pi 4 is going to be the master in my i2c network. This ...
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Bidirectional logic level converter with voltage regulator and 5 volt microcontroller
I have to use an N-channel enhancement mode Mosfet based Bidirectional logic level converter along with a fixed 3.3 voltage regulator along with 5 volt micro controller. I am powering the low voltage ...
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