Application of dynamic power supply scaling in a low-energy ATM interface

The potential for saving energy by employing dynamic power supply scaling in an ATM (Asynchronous Transfer Mode) interface circuit is analyzed and simulated. Feedback is used to adjust the power supply based on how full the input buffer is. Either a DC-DC converter or multiple supply voltages can be used. Self-timed processing circuitry allows the feedback to control the speed fairly precisely, even incorporating variations in process and operating conditions into the loop. The trade-offs and requirements for buffer size, converter response time, and control algorithm are discussed. Significant energy savings are possible if the power supply voltage can be adjusted quickly. A similar analysis can be used for applications other than an ATM interface.