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Electronics => Beginners => Topic started by: ammjy on November 16, 2019, 05:31:16 am

Title: Question about Differential amplifier.
Post by: ammjy on November 16, 2019, 05:31:16 am
Hello,

Thanks you for your time.

I have a question about differential amplifier.

I would like to know what does RC circuit that connected with Vout 1 doing in this differential amplifier.

it is just load might be ?

Please, let me know !
Title: Re: Question about Differential amplifier.
Post by: Ian.M on November 16, 2019, 07:38:13 am
I would expect a part designated RL to be the load.  The series capacitor feeding RL is to block the DC voltage on the collector of T1.
Title: Re: Question about Differential amplifier.
Post by: David Hess on November 16, 2019, 01:30:18 pm
It is AC coupling the load so I assume this is for an audio application.
Title: Re: Question about Differential amplifier.
Post by: Audioguru again on November 16, 2019, 05:32:18 pm
Many audio amplifier differential amplifier circuits are DC-coupled.
Title: Re: Question about Differential amplifier.
Post by: David Hess on November 16, 2019, 07:10:55 pm
Quote from: Audioguru again on November 16, 2019, 05:32:18 pm
Many audio amplifier differential amplifier circuits are DC-coupled.

Sure, but you would not DC couple the output from half of a differential pair because of the large level shift unless you performed a second level shift.  The output from one half has a very large offset.