From eac6e3c70ba7b87fe07e3d7c88459d610bc7c76d Mon Sep 17 00:00:00 2001 From: Werner Almesberger Date: Mon, 14 Mar 2011 21:31:55 -0300 Subject: [PATCH] atben/README-PCB, atusb/README-PCB: various minor clarifications - README-PCB: added imperial units for board thickness - README-PCB: changed surface finish recommendation to prefer ENIG more strongly - README-PCB: removed instructions for Gerber file generation from "interpretation of files section" - README-PCB: mention common coordinate system origin --- atben/README-PCB | 7 +++---- atusb/README-PCB | 6 +++--- 2 files changed, 6 insertions(+), 7 deletions(-) diff --git a/atben/README-PCB b/atben/README-PCB index a50e8ca..d6ddbb4 100644 --- a/atben/README-PCB +++ b/atben/README-PCB @@ -1,8 +1,8 @@ Board characteristics: - stacking: 2 layers, solder mask on front and back, silk screen on front -- board material: FR4, thickness 0.8 mm, 1 oz copper -- surface finish: ENIG (preferred) or tin +- board material: FR4, thickness 0.8 mm (1/32"), 1 oz copper +- surface finish: ENIG recommended - via holes: diameter is nominally 10 mil, but any size <= 15 mil can be used - mechanical tolerances: <= +/- 0.1 mm on all sides @@ -22,8 +22,7 @@ atben.drl Excellon drill file Interpretation of files: -- do not print PCB edges on front/back copper -- do not print component values on silk screen +- for all coordinates, the origin is the lower left corner of the board - the center (!) of the board edge line marks the true board edge, e.g., Edge line (5 mil) diff --git a/atusb/README-PCB b/atusb/README-PCB index 1c82a1c..194687d 100644 --- a/atusb/README-PCB +++ b/atusb/README-PCB @@ -1,8 +1,8 @@ Board characteristics: - stacking: 2 layers, solder mask on front and back, silk screen on front -- board material: FR4, thickness 0.8 mm, 1 oz copper -- surface finish: TBD, both ENIG and tin are acceptable +- board material: FR4, thickness 0.8 mm (1/32"), 1 oz copper +- surface finish: TBD, ENIG is preferred - via holes: diameter is nominally 10 mil, but any size <= 15 mil can be used - mechanical tolerances: <= +/- 0.1 mm on all sides @@ -22,7 +22,7 @@ atusb.drl Excellon drill file Interpretation of files: -- do not print PCB edges on front/back copper +- for all coordinates, the origin is the lower left corner of the board - do not print component values on silk screen - the center (!) of the board edge line marks the true board edge, e.g.,