All Questions
Tagged with level-shifting uart
22
questions
0
votes
2
answers
99
views
Low drive strength of level shifter
What part of a level shifter datasheet indicates drive strength?
I have an MCU and sensor connected over UART (115200 baud). The MCU is 3.3V and the sensor is 1.8 V, so I'm using a level shifter in ...
- 465
1
vote
1
answer
356
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How to choose pull-up resistor values for level shifting circuitry for serial communications
I recently joined a new project where two ESP32-WROOM-32UE modules on separate circuit boards talk to each other via the UART pins. The distance between the two boards is roughly 1 meter of cable ...
- 475
1
vote
1
answer
194
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UART level shifter: strange level
This is my circuit
Scoping on the UART host side I have the following trace
But on the device side (3.3V) I have this trace
Not sure on what I am doing wrong there...
Using this NMOSFET: BSD840N
- 187
0
votes
1
answer
365
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Level shifting using MOSFET
I am trying to shift the UART voltages of a 1.8 V device to 3.3 V.
I have implemented the following circuit using the RYC002N05 MOSFET:
After checking the output signal with an oscilloscope, I saw ...
- 57
0
votes
0
answers
256
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5v ALDL 8192 Baud to esp32
I've been working on a diagnostics program for my old diesel, I need the TX/RX pins of my esp32 to connect to the 1 wire ALDL port. I believe I've found a suitable way using the following circuit
Im ...
- 21
0
votes
1
answer
472
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UART 1.8V logic level translator
In my circuit i need to make a possibility to connect 2.5, 3.3 and 5V UART interfaces to my 1.8V. Therefore i need to make logic level translation. I find this 1 channel chip SN74LVC1T45, that convert ...
- 3
0
votes
0
answers
289
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Level shifter problem
I have a question regarding a level shifter schematic that I've implemented. I need to connect a 1v8 logic UART device to both an Arduino and a TTL232-3V3 cable. The Tx side works as expected and I ...
1
vote
1
answer
1k
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setting USB to UART input/output/VCC levels for general situations
I want to make a usb-serial adapter using CH340E(datasheet) chip, and use it on 3.3V or 5V microcontrollers alike, without using a switch or jumper. I've read this and this questions but there, the ...
- 2,017
1
vote
1
answer
810
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UART single-wire half-duplex level conversion
I have a single-line transmission device, I use the oscilloscope to check the waveform
Always keep high potential (12V) and low potential (0V), change to logic analyzer test and find that it can be ...
- 11
-1
votes
1
answer
203
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Level Matching Circuit
How does this circuit work?
Where VDD = 5 V (MCU) and VDD_1V8 = 1.8 V.
It is a recommended circuit to use UART communication when the voltage level are not the same, I think.
- 111
1
vote
1
answer
1k
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UART RX in VHDL
I have to set up a UART transmitter and receiver using a Spartan 3 board. I've got the transmitter set up already and verified it with the arduino terminal using this FTDI breakout.The receiver is ...
- 937
1
vote
1
answer
735
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How does this USART level shifter circuit work?
I'd like to ask how 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, in ...
- 11
2
votes
3
answers
15k
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1.8V UART with 3.3V UART
I have Quectel EC25 module comes with GPRS and GNSS in built, this module needs supply of 3.3V and it's UART works at 1.8V (default Baudrate is 115200) - But i have a processor ATMEGA2560V running at ...
- 527
-1
votes
2
answers
303
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LPC1769 and ATMega88 UART interface
I am referring below schematics for implementation.
LPC1769 -- > 3.3V Powered
AtMega88 -- > 5V Powered
LPC1769 UART pins are 5V tolerant. And due to some reason, can't operate AtMega88 on 3.3V ...
- 739
0
votes
3
answers
413
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Driving a CMOS 1.8V input with a CMOS 5V output
I'm trying to drive a Telit UL865 UART 1.8V input with a ATMega32u4 UART 5.0V output. Both of these gates are CMOS. The datasheet for the Telit says that it has a 5K to 12K pullup on the input. I ...
- 181