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About the VIH of Analog switcher "MC14052/4053/4066&quo

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wizz

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74lvc07 3.3v to 5v

I used 3.3V MCU and CPLD to control several 5V MC14052/4053/4066s.

The 3.3V mcu/cpld 's Vohmin = 2.4V.
The MC14052 datasheet said the Vihmin = 3.5V, but VihTYP = 2.75V.

Can they work?

(BTW: I don't want to use 74lvc2425/74lvc07 to change IO level.)

thx.
 

bman

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mc14052 -mac

As you guessed from the data sheets, CD405x's with a 5V supply won't work reliably when driven by 3.3V logic.

Try the 74HCT405x series or 74LC405x. They have TTL input logic levels (2.4V Vh, 3.15V max)

See http://www.philipslogic.com/products/switches/4052/ for data sheets.

You should also probably use pull-up resistors on the 3.3V drive signals to be sure the "1" voltage goes all the way up.
 

wizz

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logic levels for a 4053

Thank you very much.
 

flowers

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mc14052

Hi, wizz:

If your cpld has the 5V input tolerence, you can simple driver the TTL 5V input by cpld by sending the 'Z' in VHDL with an extra pull resistor to 5V.

regards
flowers
 

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