DIFFERENTIAL SWITCH DRIVE CIRCUIT AND CURRENT-STEERING D/A CONVERTER

摘要

A differential switch drive circuit (10) for driving a differential switch circuit (4) having a first and a second switch element (1,2) each of which has one end connected to a current source (3), comprises a current source (5), a current control circuit (6) which includes a pair of transistors having a pair of differential input terminals (A,B) and a pair of differential output terminals (X,Y) and having a common connection portion connected to the current source (5), and load elements (7,8) each of which is connected to the pair of differential output terminals (X,Y). In accordance with the voltage at the pair of differential input terminals (A,B), the differential switch drive circuit (10) outputs to the pair of differential output terminals (X,Y) an output voltage having a steady state where two values are each substantially constant and a transient state where the value transitions between the two values. At this point, currents flowing through the pair of transistors are controlled such that the sum of values for currents flowing through the load elements (7,8) in the steady state of the differential output voltage is different from the sum of values for the currents flowing through the load elements (7,8) in the transient state.