Entendo que PWB (printed wiring board) e PCB (printed circuit board) são coisas diferentes.

À pergunta se existe alguma diferença entre PWB e PCB, um especialista do site CircuitInsight.com, responde:

"This question has been discussed numerous times at IPC meetings and usually enables a fair amount of emotion.

All of the following are possible uses, depending on your age, geographic location (slang usage), and where/how you got your training. I'm sure there are more.

PB - printed board. the most generic term for a bare board

PWB - printed wiring board, one of the first uses when the issue was only a point to point connection.

PCB - printed circuit board, where the width, side to side and multi-layer relationship(spacing) of conductor runs has or is designed to have a specific effect on circuit operation other than just a point to point connection. Circuit impedance is a primary issue. In approximately 1999 the IPC Technical Activities Executive Committee made a mandate to only use the term PCB for all new document development because more often than not the printed circuitry design will have an impact on function."

Conforme explicado, PWB se refere ao circuito ponto a ponto (point to point). Esta informação também pode ser confirmada neste vídeo, onde se abordam os dois tipos de circuito: https://youtu.be/BGNA_CwzYIw