Pioneer PBD001A / PBD002A power mosfets ics

ubergeeknz

Member
2018-08-31 12:32 pm
I've picked up the power amp module of a pioneer multichannel receiver (appears a handful of models used this power amp module) and it's using these rather unusual output devices.

They appear to be power mosfets of some description.

Has anyone experience with these? I found a circuit diagram, and I do have the entire module (looks like one channel was dead as those outputs are missing) .. might these be worth pressing into use for a diy 2 channel amp? The specs on the receivers seem not bad (110wpc @ 0.09% 8Ω) but could surely be improved upon... TIA IMG_20191123_220619.jpg Screenshot_20191123_221512_com.google.android.apps.docs.jpg 1574500873707.jpg
 
I found a circuit diagram, and I do have the entire module (looks like one channel was dead as those outputs are missing) .. might these be worth pressing into use for a diy 2 channel amp? The specs on the receivers seem not bad (110wpc @ 0.09% 8Ω) but could surely be improved upon...
The amp architecture needs various improvements to get better performance, its probably needing a current mirror load for the differential pair (there is already a current mirror that seems to do nothing but drive another current mirror, perhaps it can be repurposed). Such a mirror load will increase gain, thus increase feedback (but need compensation cap changes). It will also eliminate even-order distortion from the differential pair.



The VAS is a single transistor, that's usually improvable by either cascoding or adding an emitter-follower stage to buffer the input stage from the VAS.