R-2R digital-to-analog converter having transistors of equal emitter size

摘要: A digital-to-analog converter has a plurality of switches, each which being responsive to bit digital signal having n bits, selectively pass therethrough weighted current magnitude 2 i-1 Ic where i is an ith bit. The respective flows through corresponding transistor into resistor ladder circuit. circuit arms, receive from the emitter transistor. further includes base resistors connected in series such that bases transistors are with junctions r1-r7. carry first therethrough. control BC for controlling series-connected maintain voltages two predetermined always same.