Hello,
I’m using the LTC4381 and I’m seeing a relatively long soft-start / turn-on time that seems to be dominated by the recommended GATE network.
In the datasheet, the GATE pin is shown with a minimum of C2 = 47 nF (to GND) and a 33 Ω series resistor. With these values, my measured turn-on time is approximately ~70 ms, which is too slow for my system (I’m targeting around ~10 ms).
Questions
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If I reduce C2 below 47 nF and/or change the 33 Ω resistor, what are the expected downsides?
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Is the concern loop stability (e.g., current-limit amplifier oscillation), increased inrush current, ringing/EMI, or something else?
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Are there typical symptoms/waveforms that indicate it has become unstable?
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Are there ADI-recommended ways to shorten turn-on time while keeping the circuit stable and protected?
For example:-
Alternate GATE RC arrangements (split capacitors, asymmetrical charge/discharge paths with a diode + resistor, etc.)
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Any other supported approach that preserves current limiting / protection behavior
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If the long turn-on is fundamentally limited by the LTC4381’s GATE pull-up capability, is there an alternative part you’d recommend for a similar function but with a faster turn-on requirement?
Thanks in advance for any guidance.
Best regards,
Hüseyin
