Title :
A digital CMOS programmable clock generator
Author :
Holler, Paul T. ; Lee, Hyun
Author_Institution :
AT&T Bell Labs., Allentown, PA, USA
Abstract :
The digital CMOS software programmable clock generator (PCG) was designed as a macro cell to provide quadrature clocks for the Hobbit based Personal Communicators. The PCG produces a highly accurate variable frequency system clock from 20 kHz to 100 MHz (10 kHz to 50 MHz in quadrature), while using a single inexpensive crystal oscillator as a reference. Both the frequency and tolerance of PCG can be programmed by the user. This cell resides inside the system control chip and has a bus interface allowing local storage of programmed data. Control signals which start and stop operation come from a power management portion of the chip. The output frequency can be changed on the fly
Keywords :
CMOS digital integrated circuits; clocks; crystal oscillators; personal communication networks; pulse generators; 20 kHz to 100 MHz; Hobbit; bus interface; crystal oscillator; digital CMOS; macro cell; output frequency; personal communicators; power management portion; programmable clock generator; quadrature clocks; system control chip; variable frequency system clock; Application software; Circuits; Clocks; Costs; Energy consumption; Frequency; Latches; Microprocessors; Power generation; Switches;
Conference_Titel :
ASIC Conference and Exhibit, 1994. Proceedings., Seventh Annual IEEE International
Conference_Location :
Rochester, NY
Print_ISBN :
0-7803-2020-4
DOI :
10.1109/ASIC.1994.404558
