Composite TPA6120 with servo HPA

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I've just finished my own design of a composite TPA6210 headphone amplifier helped along by a DC servo with a startup delay relay. The servo is probably not needed, as there is minimal DC with it left out of the loop.

All parts are through-hole for my shaky hands, with the exception of the TPA6120 itself. I needed some help getting that on the board, but I imagine it would be straightforward for anyone with non-shaky digits :D

TPA6120 HPA small.jpg

Distortion is a very respectable 0.0003% at 1V peak-to-peak and 0.00038% at 1Vrms.

TPA6120 1V p2p.png TPA6120 1Vrms.png TPA6120 FR.png

I'll post the schematic if anyone is keen.
 
Founder of XSA-Labs
Joined 2012
Paid Member
Nice work DHM! What happened to the B in your name?!!!

I am surprised it needed a servo? What was offset without the servo?

What is the other opamp for?

On TSOP packages, just apply a moderate blob of solder along the pins and with flux, they will wick up along the pins and pads, just run the iron back and forth along the pins like you are playing a washboard. Use solder wick dipped in flux if you have too much and cleans up nicely. No precision soldering needed.
 
Last edited:
Nice work DHM! What happened to the B in your name?!!!

It went the way of the dodo :D. It was bugging me.

I am surprised it needed a servo? What was offset without the servo?

The servo is not really needed. Without it in place the offset is <5mV. But the amp is DC coupled front to back so hopefully any minor source DC will be handled.

What is the other opamp for?
Have a look at the schematic below :)

TPA6120.png
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.