How can I indicate pin 1 on a SMT package footprint without silkscreen?

Sometimes when I order PCBs from a board house, I omit the bottom silkscreen for budgetary reasons. When I place surface-mount chips on the bottom of the board, I then end up with a footprint that doesn't indicate the chip orientation. How can I clearly indicate pin 1 with the remaining layers in a way that will be clear but not significantly impact the PCB size or cause issues when soldering?

PCB Assembly, pcb manufacturing
November 2, 2023

Have a differently shaped solder mask on pin 1.

For surface mount processors, you could have the pin 1 pad be noticeably longer than the others.

Oliver Smith

Oliver is an experienced electronics engineer skilled in PCB design, analog circuits, embedded systems, and prototyping. His deep knowledge spans schematic capture, firmware coding, simulation, layout, testing, and troubleshooting. Oliver excels at taking projects from concept to mass production using his electrical design talents and mechanical aptitude.

Oliver Smith

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