waqas5304
Member level 1
use amplifier as microphone
hi
i am using INA163UA instruementation amplifier to detect output of dynamic microphone of 5 ohm impedance. after detecting the signal i amplify it and feed it in summing amplifier and than using audio amplifier ssm2211 i drive a headphone of 8 ohms. the INA163U isbeing with single supply. the 15 v supply of INA163UA is being controlled by on/off switch. the problem is when the switch is ON and the microphone is unplugged , INA163UA generate excesisve noise that is amplifeied and fed into the headphone, moreover the current increases also. when the microphone is plugge din the noise is low.
i have tried everything but the problem is same. i hope some one must have solution
waqas
hi
i am using INA163UA instruementation amplifier to detect output of dynamic microphone of 5 ohm impedance. after detecting the signal i amplify it and feed it in summing amplifier and than using audio amplifier ssm2211 i drive a headphone of 8 ohms. the INA163U isbeing with single supply. the 15 v supply of INA163UA is being controlled by on/off switch. the problem is when the switch is ON and the microphone is unplugged , INA163UA generate excesisve noise that is amplifeied and fed into the headphone, moreover the current increases also. when the microphone is plugge din the noise is low.
i have tried everything but the problem is same. i hope some one must have solution
waqas