Patent ID: 9576165
Date: 2017-02-21
CPC Classifications: G06F,G06K,H04N

Claim:
1. A security module comprising: a processor configured to process at least one audio/video data stream; an interface comprising a plurality of contacts including a power supply contact and a clock contact configured to receive a clock signal; a frequency divider configured to divide a frequency of the clock signal to generate a divided clock signal, or a frequency multiplier configured to multiply the frequency of the clock signal to generate a multiplied clock signal, or both; a voltage detector configured to measure a voltage on the power supply contact and to categorize the measured voltage as pertaining to one from a plurality of predetermined voltage ranges; and a multiplexer configured to select the received clock signal or the divided clock signal or the multiplied clock signal for operating the security module; wherein said security module is configured to function according to any one from a plurality of predetermined operation modes, each of the predetermined operation modes having a frequency of operation corresponding to a frequency of one of the received clock signal, the divided clock signal, or the multiplied clock signal, the predetermined operation modes including any communication protocol from a plurality of different communication protocols or any class from a plurality of classes of a communication protocol; and wherein the security module is configured to monitor for a change in a category of the measured voltage from the voltage detector on a frequent basis and, when the security module detects the change in the category, to switch to a different mode and to cause the multiplexer to select between the received clock signal or the divided clock signal or the multiplied clock signal corresponding to the different mode.