| 摘要 |
<p>A microcircuit (12) includes core (14) and other portions (16), which receive different supply voltages from disparate sources. An electrostatic discharge protection (ESD) circuit internally connects the lower and higher voltage terminals together with a diode (32), poled so that the diode conducts if the nominally lower voltage supply exceeds the higher voltage supply. A shut-down circuit (24) is provided for sensing the voltage of the higher-voltage source, and shutting down the lower-voltage source any time the higher-voltage source drops below either the actual voltage (in one embodiment) or nominal voltage (in another embodiment) of the lower value source.</p> |
