Texas Instruments Incorporated
Multiplying digital to analog converter with increased multiplying bandwidth

Abstract:

A multiplying digital to analog converter (MDAC) includes a first resistor configured to be selectively connected to a current output node based on a first bit of a first portion of an input digital code and a second resistor configured to be selectively connected to the current output node based on a second bit of the first portion of the input digital code. A resistance of the second resistor is a resistance of the first resistor scaled by a factor. The MDAC further includes a first capacitor configured to be selectively connected to the current output node based on the first bit of the first portion and a second capacitor configured to be selectively connected to the current output node based on the second bit of the first portion. A capacitance of the second capacitor is a capacitance of the first capacitor scaled by an inverse of the factor.