[SOLVED] Clarification regarding SN74HCT14 schmitt Inverter

[shashy.br]

HI,


I am planning to use a digital attenuator (HMC424LP3 from HITTITE) for my design of a X band Synthesizer unit,

Since the component requires negative control they have mentioned the 74HCT04 can be used as a level inverter for -5V/0V control pins of the Attenuator.

Hence i have selected a component SN74HCT14D for this application !!!

Will connecting the VCC pin of the IC with GND and the GND pin of the IC with -5V affect the component SN74HCT14D?

https://obrazki.elektroda.pl/3046804200_1351830268.jpg

 

[FvM]

The suggested circuit should work. Alternatively you can refer to CD4053 analog multiplexers, that allow a level conversion without external components.

 

[jiripolivka]

I have used this inverter with Hittite attenuators, without any problem. The diagram shows, however, a 7404 while you write about 7414 and CD4053.If their OUTPUT is TTL, then any of them should also work.
The 7404 is simply powered by 0/+5V but "buried" under zero volts. The input 5V Zener is important as it allows this level shift.

 

[FvM]

The diagram shows, however, a 7404 while you write about 7414 and CD4053.If their OUTPUT is TTL, then any of them should also work.

The Hittite suggestion shows a CMOS 74HC04, but according to the control voltage specification, TTL level can work. Any other level converter solution with 0/-5V output level will do as well.

 

[shashy.br]

thank you all for your comments