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Once the circuit was functioning correctly on the breadboard, it was time to turn it into a PCB. I used the free version of Eagle to design the board.
The completed Eagle files for this project can be found here.
The first thing to do was transfer the schematic from the datasheet into Eagle.
The schematic uses header connectors for the potentiometers and switches so they can be easily connected to the board. The bottom left shows the basic power input, an input between 10V and 26V is acceptable, and will effect the maximum output amplitude available. The top right shows the two outputs available.
The blue area is for the Total Harmonic Distortion (THD) adjustment. If the T/S_SW component is not set, no THD will be made. Below that in red is the Symmetry adjustment. Similarly if the SYM_SW switch is not set, then no Symmetry adjustment will be made. The green area is for the timing resistors, up to three potentiometers can be connected to enable coarse and fine adjustments. In yellow is the timing capacitors and switch to select between the two frequency ranges. Finally in purple at the bottom right is the 'phantom ground' which sets a middle voltage between the two voltage inputs.
Now that the schematic was done, the next part is to lay out the components on the board.
The board is a single sided board with only three jumpers. It uses only through hole parts, and is approximately 5cm squared. Below are some 3D renders of the board layout.