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mosfet

motor driver suggestions - 6v 6a stall

I am looking for suggestions on how best to drive my Pololulu motors on my MopBot.  This bot is basically a swiffer mop attached to the bot which it pushes around so it requires more torque than the usual small bot I have done before.  These motors are rated 450 ma @6v with no load and 6 A stall.  I am using 6 NiMH AA batteries in series for about 7.2V - 7.5V although could go higher if needed.

Gives all directions for two motors
I designed this circuit for those interested in controlling motors that require a lot of Amperage, but have gotten frustrated over trying to create a MOSFET … Read more

Depletion Mode MOSFETs

Ok. I tried, I'm simply too dumb to understand depletion mode mosfets. Specifically, how to drive it with one voltage source. Something about using an op-amp as an inverter to drive the gate? I don't suppose someone has a sample schematic? The end goal is to find a 1A rated, normally on switch, in a SMD package.

Relay vs H-bridge question

most of the time I use an L298D motor driver IC for controling motors. However i find that the 1+ voltage drop is anoying. Some motors just dont go fast enough. 

Using a 7.2V power supply, leaves about 6V going to the motors and, as I understand it, the L298D is not designed to take in higher voltages. Although I think it can handle quite a bit if you cool it properly.

Sweeps the floor using ultrasound, IR, and an encoder for obstacle detection/avoidance
Using a
this is a follow-on to an earlier proof-of-concept robot found here: http://letsmakerobots.com/node/36052 The brush part of this sweeper is from a Shark hand held … Read more
Run 2 Motors, Fwd and Rev with PWM
I found this site for almost a year ago and I must say it is incredible! Full of useful information and creative, helpful people! When I saw Chris the Carpenter … Read more