A Programmable FSK-Modulator in 350nm CMOS Technology

This paper describes the design of a programmable FSK-modulator based on VCO and its implementation in 0.35m CMOS process. The circuit is used to transmit digital data at 100Kbps rate in the frequency range of 400-600MHz. The design and operation of the modulator is discussed briefly. Further the characteristics of PLL, frequency synthesizer, VCO and the whole design are elaborated. The variation among the proposed and tested specifications is presented. Finally, the layout of sub-modules, pin configurations, final chip and test results are presented.

Authors:

• Nasir Mehmood
• Saad Rahman
• Vinodh Ravinath
• Mahesh Balaji

Keywords:

• FSK Modulator
• CMOS
• VCO
• Phase Locked Loop
• Frequency Synthesizer.

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