I accidentally attached SRF-04’s Echo output pin with -9 volt, now its not working,
can any body tell me how can i repear it, so i could make it usable for other projects
That pin is not intended to be powered - you’ll likely need to purchase a replacement.
ya I know, but It was an accident, I bought 5 SRF-04 from ROBOTSHOP, all were working but during my final year project I made a mistake and put negative -9 volt to that pin ,
it means It can not b repaired
Correct. It’s a fairly integrated circuit with surface-mount components. We do not offer such a repair service nor does the manufacturer. The simple task of trying to figure out which modules are no longer functional would cost more then replacing the module.