Low-power stereo headphone and mono speaker driver.
To access files, click on the tiny paperclip in the upper left corner.
Changes for Rev04:
Speaker connector. Responding to universal criticism about the tiny screw terminals of the speaker connector, I replaced it with a spring-loaded connector. This connector can be retrofitted onto the Rev03 PCB, but you will need to cut off the rear pins and put a bit of VHB tape under the connector to keep the stubs of the rear pins to from shorting out to the PCB.
Low-voltage operation. This module deliberately disables the outputs when the +12V rail goes below about 10V. I did this to fix a power-on thump problem. However, several users were interested in using this module with reduced voltages, esp running off of 9V batteries. So I changed the shutdown levels to about 7V, which still seems to keep the thump problem under control, but allows for operation with a 9V battery regulated to 8V.
Aux phone jack. These modules never seem to have enough phone jacks. Some users want to send signals to an off-board effect box, then route the returns through the SPKR module. Other users want to take the line-level aux outputs (LOUT, ROUT, MONO OUT) and send them off-board. For both of these cases, I added an uncommitted stereo phone jack, which can be wired either to inputs or outputs.