A 480-MHz, multi-phase interleaved buck DC-DC converter with hysteretic control

• Main Authors: Schrom, G., Hazucha, P., Hahn, J., Gardner, D.S., Bloechel, B.A., Dermer, G., Narendra, S.G., Karnik, T., De, V.
• Format: Conference Proceeding
• Language: English
• Subjects: Applied sciences; Capacitors; Circuit properties; Circuits; Clocks; Convertors; DC-DC power converters; Electric, optical and optoelectronic circuits; Electrical engineering. Electrical power engineering; Electrical machines; Electronic circuits; Electronics; Energy consumption; Exact sciences and technology; Frequency; Hysteresis; Integrated circuits; Integrated circuits by function (including memories and processors); Microprocessors; Power electronics, power supplies; Power generation; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Signal convertors; Voltage
• ISSN: 0275-9306; 2377-6617
• DOI: 10.1109/PESC.2004.1354830

We propose an on-chip 1.8 V-to-0.9 V DC-DC converter aimed to reduce the input current and decoupling requirements of future microprocessors. By utilizing a 90-nm CMOS process, employing a four-phase hysteretic control, and operating at ultra-high frequency of 480-MHz, we achieved a 10% output droop with only 2.5 nF of on-chip decoupling, for 0.5 A of load current. No off-chip decoupling was connected to the output. At 480 MHz the measured efficiency was 72%. At 250 MHz, the efficiency improved to 76% at the cost of a 17% droop or larger decoupling of 11.5 nF. A converter with 100 A rating would require a capacitor of 0.5 /spl mu/F, which is comparable to the size of an on-chip capacitor of a typical microprocessor.