Demo, JUNE 15, 2007
| Author Name: | Zdravko Lukic |
| Title: | Universal and Fault-Tolerant Multiphase Digital PWM Controller IC for High-Frequency DC-DC Converters |
| Abstract: |
This work presents a flexible 4-phase digital PWM controller IC for
Switch-Mode Power Supplies that can be used with interleaved,
multi-output, and parallel dc-dc switching converters operating at
frequencies up to 10 MHz. The IC can be programmed to operate with any number of phases and it is fault-tolerant. If during the interleaved mode a failure in one of the phases occurs, it automatically switches to operation with reduced number of phases by disabling the critical phase and adjusting the angles of the remaining ones. The key element is a new multiphase digital pulse-width modulator that utilizes a programmable counter, a delay line, and a digital logic with the variable number representation. This IC is realized in a standard 0.18 um CMOS process and exhibits low power consumption of 45 uA/MHz per phase. The controller operation is also experimentally verified with a 1 MHz, 25 W, 4-phase interleaved buck converter. |