Design and Applications of a CMOS Analog Multiplier Cell Using the Differential Difference Amplifier
This paper presents design techniques for a wide input range CMOS differential difference amplifier (DDA) and discusses its application as a basic block in the implementation of a simple four-quadrant multiplier cell. The cell can be configured as an amplitude modulator or a one-over circuit, which are widely used in many analog signal processing applications. The DDA can also be reconfigured as an opamp, and hence can be used to design many of the opamp-based multiplier circuits. The DDA amplitude modulator (AM) uses a transistor and a resistor as the only components external to the DDA. A DDA one-over circuit, which provides an output proportional to the inverse of the input, is also achieved with the same level of simplicity. High-frequency effects due to the DDA’s finite gain-bandwidth (GB) and MOS parasitic capacitances are investigated. Experimental results obtained from a 2 µm CMOS MOSIS chip are given.
KeywordsAmplitude Modulator Differential Pair NMOS Transistor Analog Integrate Circuit Analog VLSI
Unable to display preview. Download preview PDF.
- 1.Huang, S.-C., Ismail, M., “A CMOS differential difference amplifier with rail-to-rail fully-differential outputs” (to be published).Google Scholar
- 6.Ismail, M., Huang, S.-C., Sakurai, S., “Continuous-time signal processing,” in Analog VLSI: Signal and Information Processing, edited by M. Ismail and T. Fiez, ch. 3, McGraw-Hill, 1994.Google Scholar
- 7.Mead, C.,Ismail, M., Analog VLSI Implementation ofNeural Systems. Kluwer, 1989.Google Scholar
- 8.Stremler, F. G., Introduction to Communication Systems. Addison-Wesley, 1982.Google Scholar
- 10.de la Plaza, A.,Morion, P., “Power-supply rejection in differential switched-capacitor filters,” IEEE J. Solid-State Circuits, Vol. SC-19, pp. 912–918, Dec. 1984.Google Scholar
- 11.Sackinger, E., Guggenbuhl, W., “A versatile building block: the CMOS differential difference amplifier,” IEEE J. Solid-State Circuits, Vol. SC-22, pp. 287–294, April 1987.Google Scholar