Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

3.3v to 5v level shifter

Status
Not open for further replies.
S

sirius_reamus

Newbie level 5
Newbie level 5
Joined
Sep 5, 2009
Messages
8
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Location
mumbai
Activity points
1,333
hi,

i have tried to buy max3372, lm3350 and QS3861 Ic's in Mumbai.

i have to interface aubtm-20(3.3v supply) with 8051(5v supply)

does anyone here know where i can buy these IC's or are there any alternatives to this.

level shifting is needed for UART communication betweeen autbm-20 and 8051.

thank you,

Vivek
 

74HCT family logic gates (with 5V supply) are a simple solution for 3.3V to 5V level conversion. Hopefully some types are available at your site.
 
Another solution would be using two transistors (right side circuit)
level_converter.jpg

Or using a mosfet like this (HV=5v, LV=3.3v, TxLV=3.3v in, TxHV=5v out)
https://www.sparkfun.com/datasheets/BreakoutBoards/Level-Converter-v10.pdf

Alex
 
@ALEXAN

do you think the circuits you mentioned can operate at 115200bps baud rate?
 
Last edited:

The 115200bps is equivalent to 115200 pulses /sec ,
the transistor can switch much faster than that.

About the mosfet circuit i think it can work but it is close (it takes about 5us to turn off with 10k),
with 1k resistors in the input it would work 10 times faster (switch off current is controlled with this resistor),
the turn on delay is lower (faster) and depends on the circuit driving it.

Alex
 
hi

i think most of the 8051's will work with 3.3V supply


ml
 

The transistor circuit that alexan_e has defined I have been using for years, it is cheap, it is simple, it is easy to fix :) and it works at 115,200 !
 
Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top