A device for driving a dot matrix display panel has a number of first terminals that can be connected to different signal lines in the dot matrix display panel, to carry current to or from picture elements in the dot matrix display panel. The invented device also has a second terminal and a set of switches that can selectively connect the first terminals to the second terminal. These switches enable a measurement device connected to the second terminal to measure electrical parameters at the first terminals individually, so that the electrical parameters of the device can be tested efficiently and accurately, without having to contact each of the first terminals with a probe.