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Low cost level translator <3.3v> to <3.3v or 5v>

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markbng

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3.3v translator fet

Hello,

I want to translate a 3v3 logic signal to a 3v3 or 5v logic level (output voltage voltage of pcb is 3v3 or 5v). How can I make a cheap solution that can handle signals up to 16MHz? The signal may be inverted. Can I use a picogate? The picogate can be powered by 3v3 or 5v, but has to handle the 3v3 logic input states correctly with both supply voltages. Or do you have other solution(s)? Thanks in advance.

Kind regards,
Mark Bongers.
 

hcet

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level translator 5v to 3v3

You may have a look into I²C specs form NXP formerly Philips. If I remember right, they used an BSN20. This FET should also provide the speed you need.

ep20k
 

    markbng

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markbng

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level-translator 3.3v 5v

This is my current solution. I had one unused 74HCT125 port in my application, so I use it for the level translator. I have a PNP transistor/N-FET solution (option 1) and a P-FET/N-FET solution(option 2). I am really concerned about power dissipation when switching for high to low and from low to high. Which solution is better?

Kind regards,
Mark Bongers
 

BasePointer

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level translator fet

Hi,

5V Inputs may accept 3.3V outputs. So you can directly connect them. Check min/max high/low voltage levels of your inputs.

To connect 5V outputs to 3.3V inputs a few method:
1. If your input has internal clamp diode, you can connect them with a single resistor. Look for DC injection current or clamp current in its datasheet to determine resistor value.
2. You can simply divide 5V to 3.3V. 5V output current and input impedance are important here to determine divider values.
 

ctownsend

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level translator 3.3 to 5v

use a 74HC4050. It will accept any input voltage up to 15 V, and output the voltage at VCC (+ or - 0.5V).

look at the spec sheet attached.
 

yzb1658

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3.3 v 5v level translator

I want to know how to do.
 

ctownsend

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74hc4050 3.3 to 5

yzb1658 said:
I want to know how to do.

Here is some really good information from the appnote an240 from phillips.
 

gassnico

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you can try with this component

**broken link removed**
 

ramesh

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Re: Low cost level translator <3.3v> to <3.3v or 5v

Following are bidirectional level translators. They can be used in multivoltage digital system applications. Each Port to Operate Over the Full 1.65-V to 5.5-V Power-Supply Range

Single port : SN74LVC1T45
Dual ports : SN74LVC2T45
Eight ports: SN74LVCH8T245
 

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