Abstract: A digital to analog converter having a pair of resistor strings. A first one of the resistor strings is adapted for coupling across a voltage supply. Resistors in the first resistor string produce voltages in response to current fed thereto from the voltage supply. A first switching network couples a voltage produced across a selected one of resistors in the first string across the second resistor string. The resistors in the second resistor string produce voltages in response to current passing from the first resistor string to the second resistor string through the first switching network. That is, the second resistor string is unbuffered from the first resistor string. A second switching network couples a selected one of the voltages produced at a selected one of the resistors in the second resistor string to an output.

Abstract: An integrated circuit chip is provided having an electrical circuit formed therein. A plurality of devices is formed in an active device region of the chip, such devices being connected as active devices. A plurality of additional ones such device are formed in a region adjacent to the active device region, such additional ones of the devices being connected as passive devices. The additional devices provide a dual purpose: first there presence improves the electrical characteristic matching among the devices which are to provide the active devices for the circuit; and, second, they are available to provide passive devices for use by the circuit rather then merely taking up space as a mere "dummy" previously unused by the circuit. More particularly, a plurality of first devices is formed in an active device region of the chip to provide the active devices. Each one of such first devices has the same shape and size.