TRS232: TRS-232 input impedance(Pin9~Pin12)

Steven He

Prodigy 80 points

Part Number: TRS232

Dear Sir,

As below picture(red block, Pin9~Pin12), does it is high impedance when VCC not applied before ?

Thanks!

Steven

over 6 years ago

0 Max Robertson over 6 years ago

TI__Guru 62910 points

Hi Steven,

We would like to check this on a few devices to confirm our understanding is correct, so we will get back to you later. (It may take us a few days to get the parts in our lab.)

Best regards,
Max

0 Matt Mendez over 6 years ago in reply to Max Robertson

TI__Intellectual 2885 points

Hi Steven,

Here is the information you asked for:

GND - 9 : 10.77 MΩ
GND - 10 : 33 MΩ
GND - 11 : 33 MΩ
GND - 12 : 10.77 MΩ

0 Terry Wu over 6 years ago in reply to Matt Mendez

Expert 1680 points

Hello Sirs,

Looks like the pin9~12 is hi impedance when IC no power.

Will it have problems that RS232 signal drive these pin from another PC's RS232 side ?

Many thanks !

0 Matt Mendez over 6 years ago in reply to Terry Wu

TI__Intellectual 2885 points

Hi Terry,

If you connect a PC to the "right side" pins 7, 8, 13, and 14. The high impedance of pins 9-12 should not affect it whatsoever. They are not directly connected inside the chip.

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TRS232: TRS-232 input impedance(Pin9~Pin12)