| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide methods and apparatus to provide transient event protection for circuits.SOLUTION: An apparatus includes a first clamp circuit 200. A first power circuit provides a first reference voltage VDD. The first clamp circuit directs energy from a signal node 204 to the first power circuit in response to a transient resulting from a voltage at the signal node being lower than a second reference voltage. The apparatus also includes a second clamp circuit 202. The second clamp circuit includes a transistor. A collector terminal of the transistor is prevented from having a lower voltage than the second reference voltage. A second power circuit provides a second reference voltage VSS, which is lower than the first reference voltage. The second clamp circuit directs energy from the signal node to the second power circuit in response to a transient resulting from a voltage at the signal node being higher than the first reference voltage.</p> |
