Protected DrMOS ICs enable fast AI current limiting



SmartClamp DrMOS power devices from AOS are designed for the demanding power requirements of AI servers and high-end GPUs. Each device is a synchronous buck power stage with two asymmetrically optimized high-side and low-side MOSFETs and an integrated driver. They provide precise 100-A positive and 50-A negative current limiting during high di/dt transients. The flagship AOZ53228QI extends protection to multiphase voltage regulators, helping prevent failures during frequent high peak-current events.

In AI applications, fast load transients can drive current beyond the limits of standard inductors and power stages. Conventional overcurrent protection schemes may introduce response delays that allow short current overshoot events, which can stress the high-side MOSFET, particularly under inductor saturation conditions.

The SmartClamp family mitigates this risk by implementing current limiting directly within the power stage rather than relying solely on the controller, improving response to load transients that occur in tens of nanoseconds. An internal ramp-based sensing method continuously monitors inductor current in real time, enabling cycle-by-cycle current clamping instead of reacting after fault conditions develop. Cycle-by-cycle control reduces the likelihood of inductor saturation and MOSFET overstress during AI-style burst loads.

SmartClamp devices, including the AOZ53228QI, AOZ53262QI, and AOZ53263QI, are available in production quantities with a 12-week lead time. The AOZ53228QI is priced at $1.40 each in lots of 1000 units.

Alpha & Omega Semiconductor 

The post Protected DrMOS ICs enable fast AI current limiting appeared first on EDN.



Source link