From ff4e1e3a367a290d52e90d9ddb702b93be2d8f09 Mon Sep 17 00:00:00 2001 From: Bdale Garbee Date: Mon, 25 Mar 2019 10:25:28 -0400 Subject: [PATCH] update Notebook text regarding 12V up-converter --- Notebook | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/Notebook b/Notebook index a831435..0cc1128 100644 --- a/Notebook +++ b/Notebook @@ -11,7 +11,8 @@ connect all of them to pin 4, the gpio driving the circuit. The net effect is that we're making 12V from the gpio, which means all the LED current and switcher inefficiency is coming as current through that gpio. The -measured LED current is around 7mA, so this is "safe" for the SOC, but really -not a great plan... +measured LED current is around 7mA, so this is "safe" for the SOC, but leaves +less engineering margin than we usually like. -Need to redesign this in the future to use a transistor/FET switch. +Changing the circuit to be powered from v_lipo with the gpio hooked to shdn* +and controlling a FET switch on the output might be smarter someday? -- 2.30.2