From 4220144a48f60102b238bbbae9316392ec228406 Mon Sep 17 00:00:00 2001 From: Bdale Garbee Date: Sun, 10 Oct 2010 09:26:11 -0600 Subject: [PATCH] initial documentation for Robert's amplifier for electric violin use --- electronics/audio/lm1875.mdwn | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 electronics/audio/lm1875.mdwn diff --git a/electronics/audio/lm1875.mdwn b/electronics/audio/lm1875.mdwn new file mode 100644 index 0000000..1ca8a6b --- /dev/null +++ b/electronics/audio/lm1875.mdwn @@ -0,0 +1,23 @@ +# Audio Amplifier + +This is an amplifier based on a National Semiconductor LM1875 that Bdale and +Robert built to use playing around with an electric pickup on Bdale's +violin. The ultimate objective is to have a modest effects chain with amp +and speaker that Robert can use when playing music with his friends. We chose +to start by building a high-quality amplifier. + +## LM1875 + +This part family came to Bdale's attention for other reasons, and the +apparent simplicity with which a 20 watt amplifier could be built with the +[LM1875](http://www.national.com/mpf/LM/LM1875.html) made it seem like a +good choice as a starting point. Samples +were obtained, and the first prototype wired up using the split supply +example application circuit in the data sheet just worked... and worked +brilliantly! + +## Artifacts + +A schematic for this circuit based on the data sheet reference design is in +the [hw/audio](http://git.gag.com/?p=hw/audio;a=summary) repository at +[git.gag.com](http://git.gag.com). -- 2.30.2