Patent ID: 9509310
Filing Date: 2016-11-29
CPC Classification: H03K,H04B

Claim Text:
1. A driver circuit configured to produce a pair of output signals from a pair of input signals, the driver circuit comprising: a current source connected between a first node and a supply terminal, and operative to supply a driving current to the first node; a first switch connected in parallel with the current source between a second node and a voltage regulator operative to supply a DC regulated operating voltage to a terminal of the first switch; a differential switching circuit connected between the first node, the second node, a third node and a fourth node, and operative to receive the pair of input signals at a first input node and at a second input node, and convert the pair of input signals to the pair of output signals at a first output node and at a second output node; a voltage divider coupled between the first output node and the second output node, having a first transmission gate switch and a second transmission gate switch serially connected through a fifth node of the voltage divider; a common-mode-feedback circuit coupled to the fifth node, and operative to generate a common mode control signal in response to a reference voltage and a level of voltage at the fifth node; a common mode resistance unit coupled between the third node and a ground terminal, and having a resistance value controlled by the common mode control signal; a second switch coupled in parallel with the common mode resistance unit between the fourth node and the ground terminal; a digital controller coupled to the current source, the voltage regulator, the voltage divider, the first switch and the second switch; wherein the driver circuit is operative to select between: a) a first mode of operation in which input signals and output signals are differential signals and in which current is conducted from the current source to the ground terminal, passing through the fifth node, and b) a second mode of operation in which input signals and output signals are single-ended signals and in which output voltages are generated between the voltage regulator and the ground terminal.