Sub-1-V CMOS proportional-to-absolute temperature references

Presents a new all-MOS circuit technique for very-low-voltage proportional-to-absolute temperature (PTAT) references. Optimization of supply scaling below the sum of threshold voltages is based on log companding and implemented by operating the MOSFET in weak inversion. The key design equations for current (/spl mu/A) and voltage (sub-100 mV) references and their standard deviations (around 5%) are derived by analytical analysis. Two sub-1-V sub-5-/spl mu/W integrated PTAT references are presented and exhaustively tested for 1.2- and 0.35-/spl mu/m very large scale integration technologies. Both designs report good agreement between analytical, simulated, and experimental data, exhibiting PSRR(DC)+>60 dB. Hence, the resulting PTAT circuits are suitable for very-low-voltage system-on-a-chip applications in digital CMOS technologies.

[1]  Alvarez,et al.  A CMOS Temperature Sensor For PowerPC RISC Microprocessors , 1997, Symposium 1997 on VLSI Circuits.

[2]  Francisco Serra-Graells.  VLSI CMOS low-voltage log companding filters , 2000, 2000 IEEE International Symposium on Circuits and Systems. Emerging Technologies for the 21st Century. Proceedings (IEEE Cat No.00CH36353).

[3]  Beomsup Kim,et al.  Low-power CMOS on-chip voltage reference using MOS PTAT: an EP approach , 1997, Proceedings. Tenth Annual IEEE International ASIC Conference and Exhibit (Cat. No.97TH8334).

[4]  E. Vittoz,et al.  An analytical MOS transistor model valid in all regions of operation and dedicated to low-voltage and low-current applications , 1995 .

[5]  T. R. Viswanathan,et al.  A CMOS bandgap reference without resistors , 2000, 2000 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.00CH37056).

[6]  H. Oguey,et al.  CMOS Current Reference without Resistance , 1996, ESSCIRC '96: Proceedings of the 22nd European Solid-State Circuits Conference.

[7]  E.K.F. Lee,et al.  Design of low-voltage bandgap reference using transimpedance amplifier , 2000 .

[8]  M.J.M. Pelgrom,et al.  Matching properties of MOS transistors , 1989 .

[9]  K. Sakui,et al.  A CMOS bandgap reference circuit with sub-1-V operation , 1999 .