公开(公告)号：US20170099063A1

公开(公告)日：2017-04-06

申请号：US15266458

申请日：2016-09-15

Applicant: Marvell World Trade Ltd.

Inventor： Vijay Ganwani ,  Vijay Ahirwar ,  Yui Lin ,  Sudhir Srinivasa ,  Hongyuan Zhang ,  Sridhar Narravula

IPC: H03M3/00 ,  H04L27/26 ,  H04B1/10 ,  H04L7/033

CPC classification number: H03M3/378 ,  H03M1/1085 ,  H03M1/1095 ,  H03M3/356 ,  H04B1/1036 ,  H04B2001/1063 ,  H04L7/0331 ,  H04L27/2636

Abstract: Apparatus for determining a signal-to-quantization-noise ratio of a quantization circuit includes a signal generator that generates an input test signal for input to the quantization circuit, circuitry for isolating, from output of the quantization circuit, a signal representing quantization noise, and circuitry for determining a ratio of the output of the quantization circuit to the signal representing quantization noise. The signal generator generates an analog test tone having a frequency, and the circuitry for isolating includes a notch filter filtering that frequency. Alternatively, the circuitry for isolating includes circuitry for generating a digital test signal, and a digital subtractor for subtracting the digital test signal from the output of the quantization circuit. According to another alternative, the circuitry for isolating includes a transformation circuit whose outputs represent a peak of the output of the quantization circuit and a noise floor of the output of the quantization circuit.