From 671a7762db6980f43dbab03e5c1d90e67817077a Mon Sep 17 00:00:00 2001 From: Will Langford <langfordw@gmail.com> Date: Mon, 26 Mar 2018 18:38:56 -0400 Subject: [PATCH] update --- electronics/pulseGenerator_v2.brd | 8 ++++---- electronics/readme.md | 9 +++++---- 2 files changed, 9 insertions(+), 8 deletions(-) diff --git a/electronics/pulseGenerator_v2.brd b/electronics/pulseGenerator_v2.brd index 0f16c60..2967be7 100644 --- a/electronics/pulseGenerator_v2.brd +++ b/electronics/pulseGenerator_v2.brd @@ -3032,8 +3032,8 @@ design rules under a new name.</description> <wire x1="23.9323" y1="67.6597" x2="23.9323" y2="69.215" width="0.6096" layer="1"/> <contactref element="C22" pad="1"/> <contactref element="C23" pad="1"/> -<wire x1="49.2125" y1="22.2885" x2="29.845" y2="4.8675" width="0" layer="19" extent="1-1"/> -<wire x1="48.895" y1="52.1335" x2="49.2125" y2="22.2885" width="0" layer="19" extent="1-1"/> +<wire x1="51.816" y1="52.197" x2="48.895" y2="52.1335" width="0" layer="19" extent="1-1"/> +<wire x1="49.2125" y1="22.2885" x2="51.816" y2="22.415" width="0" layer="19" extent="1-1"/> </signal> <signal name="N$13" class="2"> <contactref element="U4" pad="6"/> @@ -3671,8 +3671,8 @@ design rules under a new name.</description> <contactref element="C23" pad="2"/> <wire x1="54.6862" y1="47.879" x2="54.6862" y2="49.149" width="0" layer="19" extent="1-1"/> <wire x1="54.6862" y1="19.685" x2="54.6862" y2="18.415" width="0" layer="19" extent="1-1"/> -<wire x1="49.2125" y1="18.9865" x2="45.4025" y2="3.81" width="0" layer="19" extent="1-16"/> -<wire x1="48.895" y1="48.8315" x2="49.2125" y2="18.9865" width="0" layer="19" extent="1-1"/> +<wire x1="49.2125" y1="18.9865" x2="51.7525" y2="19.047" width="0" layer="19" extent="1-1"/> +<wire x1="48.895" y1="48.8315" x2="51.816" y2="48.895" width="0" layer="19" extent="1-1"/> </signal> <signal name="VIN"> <contactref element="JP1" pad="2"/> diff --git a/electronics/readme.md b/electronics/readme.md index 78c3fc9..4da6c34 100644 --- a/electronics/readme.md +++ b/electronics/readme.md @@ -38,7 +38,8 @@ My understanding of the waveform: - High-side gate drivers: [**LM5107**](http://www.ti.com/lit/ds/symlink/lm5107.pdf) [UCC27200A](https://www.digikey.com/product-detail/en/texas-instruments/UCC27201ADDAR/296-28428-1-ND/2638108) - I could get away with just using one of these (and using a low-side mosfet to do the discharge control). The problem with this is that then the workpiece and worktable are at high voltages whenever the machine is on. So I suspect I'll go with two... - Capacitor: [6.8uF conductive polymer](https://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=254554510&uq=636564567701952216) -- 3.3V switching regulator: https://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=254721636&uq=636571622259993391 +- [3.3V switching regulator](http://ww1.microchip.com/downloads/en/DeviceDoc/20005004D.pdf) + - [relevant reference designs](http://www.microchip.com/wwwproducts/en/en554058) - window comparator - http://www.ti.com/lit/ug/tidub01/tidub01.pdf - just need 1 x (4x) https://www.digikey.com/product-detail/en/texas-instruments/TLV1704AIPWR/296-38432-1-ND/5015597 @@ -92,9 +93,9 @@ Connecting those two regions, is the sensing and control circuitry. This region - need to tie unused low input pins of the gate drivers to ground (should be easy to bridge) - need to jumper between HS pin of the gate driver and MOSFET source (bottom of mosfet) - should use switch instead of solder jumper to switch between 5V and 12V (or better yet, have it automatically switch to the higher voltage source⦠[I can probably do this with properly rated shottky diodes](https://electronics.stackexchange.com/questions/130986/automatically-switching-from-9v-battery-to-dc-wall-adapter-on-insertion)) - - I don't have the overhad to use a normal 0.7V diode with the 5V supply. Something called an [ideal diode](https://datasheets.maximintegrated.com/en/ds/MAX40200.pdf) works for this though. - - [This one would likely scrape by for the 5V side](https://www.digikey.com/product-detail/en/central-semiconductor-corp/CFSH05-20L-TR/CFSH05-20LTR-ND/4807452) (0.5V drop at 500mA). - - Here's a [diode for the 12V side](https://www.digikey.com/product-detail/en/on-semiconductor/MBRS410LT3G/MBRS410LT3GOSCT-ND/1967073). + - I don't have the overhad to use a normal 0.7V diode with the 5V supply. ~~Something called an [ideal diode](https://datasheets.maximintegrated.com/en/ds/MAX40200.pdf) works for this though.~~ But this doesn't work above a 6V reverse voltage. + - [This one would likely scrape by for the 5V side](https://www.digikey.com/product-detail/en/central-semiconductor-corp/CFSH05-20L-TR/CFSH05-20LTR-ND/4807452) (0.5V drop at 500mA). (actually this one would work, but I think the BAT54S 200mA schottky diode in the fablab inventory would work was well. It has a higher 800mV drop at 100mA but the MCP switching regulator should be okay down to 4V) + - Here's a [diode for the 12V side](https://www.digikey.com/product-detail/en/on-semiconductor/MBRS410LT3G/MBRS410LT3GOSCT-ND/1967073), which I may not even need. - should have pull downs on both inputs to gate drivers and inputs to mosfets (for safety) - unclear if I need higher powe-rated resistors for the gate drive resistor. [They'll be undergoing high momentary currents but their average power dissipation is well below their 1/4W rating.](calculations.ipynb) -- GitLab