Digital to analog converter

Claim 2

A digital to analog converter having a digital data source for producing a series of 2n-bit serial words at a first output and a bit synchronized pulse train at a second output, comprising, in combination: conversion means adapted to receive the data source first output for sequentially converting the 2n-bit serial words into first and second parallel n-bit outputs; an n-bit digital to analog converter operatively connected to receive said conversion means outputs for converting respective ones of said outputs to corresponding analog signals; counting means adapted to receive the data source second output for periodically producing a first output signal during the nth bit interval of each of said 2n-bit words and a second output signal during the 2nth bit interval of each of said 2n-bit words; first sample and hold means operatively connected to receive said converter output signals and said counting means first output signal for sampling said analog signals during the nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; second sample and hold means operatively connected to receive said converter output signals and said counting means second output signal for sampling said analog signals during the 2nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; third sample and hold means connected to receive said first sample and hold means output and said counting means second output signal for sampling said first sample and hold means output during the 2nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; and summing means connected to receive said second and third sample and hold means analog outputs for summing said analog outputs according to a predetermined weighted ratio and for producing an analog output signal indicative of the binary value of each of the serial words.

Claim 3

A digital to analog converter according to claim 1 wherein said counting means is a 2n-bit ring counter wherein the first output signal is indicative of the nth count and the second output signal is indicative of the 2nth count.

Claim 4

A digital to analog converter according to claim 2 wherein said conversion means first parallel n bit output is representative of the n least significant bits in the 2n-bit serial word and said second parallel n bit output is representative of the n most significant bits in the 2n-bit serial word.

Claim 5

A digital to analog convertor, comprising in combination: a source of digital data for producing a series of 2n-bit serial words at a first output and a bit synchronized pulse train at a second output; conversion means connected to receive the data source first output for sequentially converting the 2n-bit serial words into first and second parallel n-bit outputs; an n-bit digital to analog converter operatively connected to receive said conversion means outputs for converting respective ones of said outputs to corresponding analog signals; counting means connected to receive the data source second output for periodically producing a first output signal during the nth bit interval of each of said 2n-bit words and a second output signal during the 2nth bit interval of each of said 2n-bit words; first sample and hold means operatively connected to receive said converter output signals and said counting means first output signal for sampling said analog signals during the nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; second sample and hold means operatively connected to receive said analog converter means output signals and said counting means second output signal for sampling said analog signals during the 2nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; third sample and hold means connected to receive said first sample and hold means output and said counting means second output signal for sampling said first sample and hold means output during the 2nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; and summing means connected to receive said second and third sample and hold means analog outputs for summing said analog outputs according to a predetermined weighted ratio and for producing an analog output signal indicative of the binary value of each of the serial words.

Claim 6

A digital to analog convertor, comprising in combination: a source of digital data for producing a series of 2n-bit serial words at a first output and a bit synchronized pulse train at a second output; conversion means connected to receive the data source first output for sequentially converting the 2n-bit serial words into first and second parallel n-bit outputs; an n-bit digital to analog converter operatively connected to receive said conversion means outputs for converting respective ones of said outputs to corresponding analog signals; counting means connected to receive the data source second output for periodically producing a first output signal during the nth bit interval of each of said 2n-bit words and a second output signal during the 2nth bit interval of each of said 2n-bit words; first sample and hold means operatively connected to receive said converter output signals and said counting means first output signal for sampling said analog signals during the nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; second sample and hold means operatively connected to receive said analog converter means output signals and said counting means second output signal for sampling said analog signals during the 2nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; third sample and hold means connected to receive said first sample and hold means output and said counting means second output signal for sampling said first sample and hold means output during the 2nth bit interval of each of said 2n-bit words and for storing an analog output representative thereof; and summing means connected to receive said second and third sample and hold means analog outputs for summing said analog outputs according to a predetermined weighted ratio and for producing an analog output signal indicative of the binary value of each of the serial words.

Claim 7

A digital to analog converter according to claim 4, wherein said counting means is a 2n-bit ring counter wherein the first output signal is indicative of the nth count and the second output signal is indicative of the 2nth count.

Claim 8

A digital to analog converter according to claim 5 wherein said conversion means first parallel n bit output is representative of the n least significant bits in the 2n-bit serial word and said second parallel n bit output is representative of the n most significant bits in the 2n-bit serial word.