摘要 |
Short-circuit protection in switched output stages is described to protect switching output stages from excessive output current in short-circuit conditions which may cause device damage. Design techniques to attain this goal include measuring currents in switching transistors by placing a scaled transistor in parallel thereto, combined with circuitry for making drain voltages substantially equal. The various techniques for short-circuit protection comprise (a) using a transistor and an operational amplifier in combination, (b) using a single transistor in place of the operational amplifier, (c) using a circuit to generate over-current detection signals, (d) providing over-current detection signals to a driver in order to reduce the output current, (e) using an inverter to feedback regulate output current, (f) using a switch to bypass the current regulator during normal operation, and (g) automatically opening this switch in an over-current situation.
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