Sites like GitHub or OSHPark often have user-submitted schematics for modules containing this chip.
Electronics stacks and repair forums are goldmines for hand-drawn schematics or high-resolution PCB photos that allow you to "reverse engineer" the diagram. Troubleshooting Your Circuit tsk105a03 schematic diagram free
Some versions allow for fine-tuning the output via a potentiometer. Basic Application Circuit Sites like GitHub or OSHPark often have user-submitted