D-a converter

Abstract

Abstract PURPOSE:To sufficiently guarantee the accuracy such as the differentiation linearity and monotonousness, by D/A conversion with the matrix circuit using a minute current source as a unit current source. CONSTITUTION:The digital data in n-bits is split into upper-rank bits (nX+nY) and lower-rank bit nZ, and the matrix circuit 1 of 2<nx>X2<ny> is composed of the use of 2<(nx+ny)> sets of the minute current sources (consisting of transistor TRQ1), and with a cross point selecting element 2 (consisting of TRQ2, diode D and TRQ3) including the minute current source provided at the cross point (Xi, Yj) of the circuit 1, this is selected according to input digital data and converted into an analog quantity. Further, analog processing is made with the ladder circuit (not shown) consisting of nZ-bits of lower rank. Further, the synthesized analog quantity obtained from this is picked up as the output. That is, the X and Y lines connected with the element 2 are used as the signal takeout line also as the control of the cross point selection.

Inventors

• 👤 Hitoshi Takeda

Bibliographic Details