Clustered Voltage Scaling

Clustered voltage scaling is a power reducing method which does not affect the overall system performance. The main idea is to run gates on a non-critical path by a low-voltage supply. Since low-voltage gates are not able to drive high-voltage gates, level-converters are needed. In order to reduce the number of level-converters, which may cancel out the power savings, they are arranged in a cluster just before a latch. First, a non-critical path is identified. Then the gates (starting at the end of the path) are replaced by low-voltage gates. If the path is still uncritical, more gates can be replaced. A main advantage of placing the low-voltage gates in front of a latch is that the level converters can be combined with the latch, leading to a latch with level-conversion function (LCF) [1]. Strategies for clustered voltage scaling can be found in [1] and [2].