A Low-Power 30MHz,6th Order Bandpass Differential Gm-C Filter on Chip Utilizing Floating Current Source

Abstract

This work employs a leap-frog Gm-C structure to design a sixth-order Butterworth and elliptic bandpass filter that the cutoff frequency (Fo = 30MHz). A continuous-time differential Gm-C biquad and its corresponding voltage-mode version are elucidated, utilizing F.C.S (Floating Current Source) circuits as fundamental components. The enhanced current source architecture exhibits a streamlined configuration. It incorporates a reduced number of transistors, which facilitates optimal utilization of the chip's area and introduces a streamlined approach to circuit design. The suggested filter topology lacks a crucial resistor component, vital in achieving integration functionality. The suggested filter incorporates a grounding configuration for all capacitors, thereby mitigating the detrimental impact of parasitic effects. The filter design has been effectively realized utilizing TSMC's 0.18μm CMOS process. The findings from simulations have been provided to validate the theoretical analysis.

Keywords

• Continuous-Time
• Gm-C Bandpass Filter
• Floating Current Source (F.C.S)
• TSMC

References

1. Feng, J., Wang, C., Zang, M., & Ren, Y. (2011, January). Realization of current-mode general nth-order filter based on current mirrors. In 2011 3rd International Conference on Advanced Computer Control. IEEE, 367-370.
2. Bozomitu, R.G., & Cehan, V. A. (2009). Vlsi Implementation of a New Low Voltage 4th Order Differential Gm-C Bandpass Filters for Different Approximation In CMOS Technology. Acta Technica Napocensis, Electronics and Telecommunications, 50, 5-12.
3. Ranjan, A., & Paul, S. K. (2011). Voltage mode universal biquad using CCCII. Active and Passive Electronic Components, 1-5.
4. Gaspar, J., Chen, S. F., Gordillo, A., Hepp, M., Ferreyra, P., & Marqués, C. (2004). Digital lock in amplifier: study, design and development with a digital signal processor. Microprocessors and Microsystems, 28(4), 157-162.
5. Hiroshi, Y. (1999). A 450kHz CMOS Gm-C Band-pass Filter with±0.5% Center Frequency Accuracy for On-Chip PDC IF Receivers. In IEEE International Solid-State Circuits Conference, February.
6. Song, H. J., & Kim, C. K. (1990). An MOS four-quadrant analog multiplier using simple two-input squaring circuits with source followers. IEEE Journal of Solid-State Circuits, 25(3), 841-848.
7. Khorramabadi, H. (1992). A CMOS line driver with 80-dB linearity for ISDN applications. IEEE journal of solid-state circuits, 27(4), 539-544.
8. Edwards, R. T., Strohbehn, K., & Jaskulek, S. E. (2000, May). A field-programmable mixed-signal array architecture using antifuse interconnects. In 2000 IEEE International Symposium on Circuits and Systems (ISCAS). IEEE (3), 319-322.

9. Ahmed, M. A., Khalaf, M. Z., & Demirel, H. (2023). Study of finfet transistor. Critical and literature review in finfet transistor in the active filter. 3 c TIC: cuadernos de desarrollo aplicados a las TIC, 12(1), 65-81.
10. Ahmed, A., & Demirel, H. (2023). DESIGN Third order Sinusoidal Oscillator Employing Current Differencing Cascaded Trans conductance Amplifiers. Gazi University Journal of Science Part C: Design and Technology, 11(3), 735-743.