The author claims in his paper below claims that the cicuit in Fig.5 on Page.4 offers Temparature independent Current.
I did not understand that circuit. Can you help me understand this?

Paper: Krishnakumar Sundaresan et al " Process and Temperature Compensation in a 7-MHz CMOS Clock Oscillator" IEEE JSSC Feb 2006

Free-Download from net : [ISCAS2003 Paper, Fig.7 on Page.3]
http://www.ece.gatech.edu/research/integrated-mems/conference%20papers/sundaresa...

Thanks in advance,
Packiaraj.V.

Hi,
The left circuit is a PTAT  current source (check any VLSI circuit book for how does it work) which generate a current that has a linear behavior with temperature. this current is then used to compensate VCTRL.

Nimrod