A D/A converter including first and second R-R2 resistor ladders and a set of
SPDT
switches. The first R-2R resistor ladder includes N type resistors coupled between
a common voltage node and an output voltage node and the second R-2R resistor ladder
includes P type resistors coupled between the common and output voltage nodes.
The R-2R resistor ladders have multiple common switch terminals, each coupling
an N type 2R resistor to a corresponding P type 2R resistor. Each SPDT switch is
responsive to a data bit for switching a common switch terminal between the common
voltage and a reference voltage. Each N type resistor may be formed in a PWell
coupled to the common (or more negative) voltage and each P type resistor may be
formed in an NWell coupled to the reference (or more positive) voltage. The SPDT
switches may be configured with equivalent switch path impedances.