The original PSP lineup isn't dead as of yet. Neur0n comes around with his Analog Block plugin which completely disables input from the [COLOR=blue !important][COLOR=blue !important]PSP's[/COLOR][/COLOR] analog stick. This is useful if your stick is jittery or just doesn't work properly. While this may not be the hardware fix that you're looking for, this is a [COLOR=blue !important][COLOR=blue !important]band[/COLOR][/COLOR]-aid solution that will definitely do the job for some of you out there.
The plugin works across all PSPs on any 6.xx ME [COLOR=blue !important][COLOR=blue !important]custom [COLOR=blue !important]firmware[/COLOR][/COLOR][/COLOR]. Installation is still the same as any other plugin. Drop it in the 'seplugins' folder residing at the root of your memory stick and add the corresponding line to your 'vsh.txt', 'game.txt' and 'pops.txt' files.
PSP = ms0:/seplugins/analog_block.prx 1
PSP Go = ef0:/seplugins/analog_block.prx 1
From there, you're all good to go. You can grab Analog Block via the Source link below.
Source: PSP Custom Firmware