Thread: Discussion H-bridge motor controller
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Old Apr 04, 2012, 02:15 AM
jeffs555 is offline
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"Simplify, then add lightness"
Joined Nov 2000
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Only problem: my high-side V-gate-to-source is only reaching ~3.8V. My mosfets need 4.5+ to turn on (they are logic type).
I just re-read your original post and it says you are using IRF540S. Those are not logic level mosfets and are only spec'd for 10v gate drive. Just because the threshold voltage is below 5v does not make them logic level mosfets. Most logic level mosfets have thresholds of around 2v. You will need logic level mosfets for use with that 5v driver.

PS There is an IRL540 that has the same 100V rating as the IRF540 but is a logic level device.
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Last edited by jeffs555; Apr 04, 2012 at 02:59 AM.
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