Analog Functional Blocks
In this chapter we have discussed two important analog functional blocks in data converters, the MDAC and the integrator. Both SC and SI circuits were considered. We showed how to calculate the noise and maximum speed of the circuits based on first order models. The maximum speed of the circuits is determined by the bandwidth and the required number of clock phases. The maximum speed normally decreases as the gain of the circuit increases. The thermal noise of the circuits can be referred to the input as a noise voltage. We showed that the noise voltage power for all the circuits is only determined by the capacitors in the circuit.
The results in this chapter will be used in chapter 9 and chapter 11 to investigate the effect of circuit imperfections on pipelined and oversampled sigma-delta converters respectively.
KeywordsNoise Source Thermal Noise Current Mirror Total Noise Clock Phase
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