Apparatus for obtaining a substantially continuously scaled analogue representing the average value of a sequence of binary words

Claim 1

Apparatus for obtaining a substantially continuously scaled analogue signal representing the average value of a sequence of binary words, comprising an accumulator for storing the sum of a sequence of words supplied thereto in binary form, a digital to analogue converter, multiplexer means for supplying the accumulator word sum to the converter, the multiplexer means being settable in a number, n, of positions in each of which it is arranged for the supply to the converter of the quotient of the accumulator word sum to a predetermined significant bit and 2n, a counter for registering the number of words supplied to the accumulator and having a capacity of registering up to 2n words, and logic circuit means driven by the counter and adapted to set the multiplexer in position for the supply to the converter of the quotient of the accumulator word sum to said predetermined significant bit and 2n and to afford at the converter a reference voltage proportional to the quotient of 2n and the number of words counted by the counter, the converter by multiplying the voltage reference and multiplexer input thereto providing an output which is the average word.