Title :
A 1.2 V NPN-only log-domain integrator
Author :
El-Gamal, Mourad N. ; Roberts, Gordon W.
Author_Institution :
Microelectron. & Comput. Syst. Lab., McGill Univ., Montreal, Que., Canada
Abstract :
A simple log-domain integrator that operates nominally with a supply voltage of 1.2 V is proposed. It does not employ PNP or PMOS transistors in the signal path. This has two advantages: i) It makes the integrator suitable for high-frequency applications. ii) The circuit can be implemented using cheap bipolar processes rather than the more expensive BiCMOS processes or the bipolar processes featuring high-quality PNP transistors. A third-order Chebyshev prototype filter, employing the proposed integrator, is realized using a semi-custom bipolar array. It consumes 282 μA per pole for a cutoff frequency of 1.5 MHz. For lower biasing currents, the circuit can operate from a supply voltage as low as 0.9 V. Detailed experimental results are reported
Keywords :
Chebyshev filters; active filters; application specific integrated circuits; bipolar analogue integrated circuits; integrating circuits; radiofrequency filters; 0.9 V; 1.2 V; 1.5 MHz; NPN-only log-domain integrator; biasing currents; bipolar processes; cutoff frequency; high-frequency applications; semi-custom bipolar array; supply voltage; third-order Chebyshev prototype filter; BiCMOS integrated circuits; Cutoff frequency; Filtering; Low voltage; MOSFETs; Microelectronics; Nonlinear filters; Prototypes; Signal processing; VHF circuits;
Conference_Titel :
Circuits and Systems, 1999. ISCAS '99. Proceedings of the 1999 IEEE International Symposium on
Conference_Location :
Orlando, FL
Print_ISBN :
0-7803-5471-0
DOI :
10.1109/ISCAS.1999.780856
