I'm trying to figure out how a Switch Mode constant-current Power Supply could work with a TTL-controlled laser module on its output. If I'm not mistaken, the constant-current is maintained by an Inductor in series with the load. My concern is that when the load is disconnected, the Inductor will instantly produce a high-voltage spike because it suddenly sees an increase in load resistance to infinity and all that "electrical momentum" basically slams into a wall.
I've thought maybe it would work to shunt the current away from the load using a sequence of switches (open alternate path, close main path) but that could be problematic as it has to happen in a consistent order and timeframe otherwise the Inductor will destroy the switches with an HV transient.
Another thing I thought about briefly was to just disable the oscillator, but the Inductor would simply coast down over a (relatively) long period of time and the laser would not shut off instantly, which is what I need.
Are there any well-known and reliable methods for rapidly toggling the constant-current through a Switched-Mode Power Supply's load?
I've thought maybe it would work to shunt the current away from the load using a sequence of switches (open alternate path, close main path) but that could be problematic as it has to happen in a consistent order and timeframe otherwise the Inductor will destroy the switches with an HV transient.
Another thing I thought about briefly was to just disable the oscillator, but the Inductor would simply coast down over a (relatively) long period of time and the laser would not shut off instantly, which is what I need.
Are there any well-known and reliable methods for rapidly toggling the constant-current through a Switched-Mode Power Supply's load?
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