摘要 |
A SINC filter for an oversampling Sigma-Delta digital to analog converter (OSDAC) having a cascaded construction that results in reduced sensitivity to capacitor mismatch. Specifically, the SINC filter circuit filter may be defined by a transfer function H(z), which is further defined by first constituent transfer functions H1(z) and H2(z). The constituent transfer functions may be implemented in a cascaded fashion. Preferably, one of the cascaded sections includes a resistor string that defines a plurality of reference voltages. A plurality of switching elements are configured to controllably switch these reference voltages to a capacitor of a tap.
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