LAYOUT FILES: (Y)et (a)nother (u)seless (D)ummy (L)oad
Eagle Shell
Latest commit 68e55d9 Apr 27, 2015 @madworm Fixed vertical offset of multi-line-text.
Some time ago KiCad changed how it handles that.


LAYOUT FILES: (Y)et (a)nother (u)seless (D)ummy (L)oad


For testing various projects I desire an adjustable constant current sink. Nothing fancy, not microcontroller controlled, not 'constant power', maybe with a display, maybe just use a DMM for that. BUT I need AMPS! I'm shooting for a device that is capable to sink 5A. At least for a limited amount of time, a couple of minutes should be enough to see if the DUT overheats and/or craps out.

It will be as simple as can be: MOSFET(s), heatsink, sense resistor(s), opamp(s), gain control, reference voltage, multi-turn pot to set the reference current. It may or may not come with binding posts.

The first opamp will amplify the voltage drop on the mOhm range sense resistor to a useful value (1V --> 1A), the second opamp will be wired in the usual follower setup driving the MOSFET(s). I don't want to use a 1R sense resistor, as this causes the device to need at least 5V for 5A. I'm aiming at something lower.

BTW. It is strictly for DC input voltages.

Before having PC-boards made, please make sure you know about your manufacturer's peculiarities! Especially drill-sizes and their tolerances may vary too much and give you trouble.