Programmable-gain amplifier, corresponding device and method

An electronic device, comprising:

• a programmable-gain amplifier including;
• two pairs of complementary cross-coupled transistors, each transistor in one pair having a series current flow path with one of the transistors in the other pair, first and second coupling nodes being formed at interconnections between the pairs and the two pairs being coupled between a supply voltage node and a reference voltage node;
• first and second sampling capacitors coupled to the first and second coupling nodes, respectively;
• first and second input circuits having inputs configured to receive first and second input signals, respectively, and having first and second outputs, respectively;
• a switching circuit configured to couple during a sampling interval the first and second outputs of the input circuits to the first and second coupling nodes to charge the first and second capacitors and thereby sample the first and second input signals, and the switching circuit further configured to provide during a regeneration interval a supply voltage on the supply node and a reference voltage on the reference to generate a voltage across the first and second coupling nodes that exponentially increases over the regeneration;
• electronic circuitry coupled to first and second coupling nodes of the programmable-gain amplifier.

A method, comprising:

• storing values of input signals on first and second coupling nodes during a sampling, interval,
• exponentially amplifying a voltage across the first and second coupling nodes during a regeneration interval after the sampling interval, the exponentially amplifying including energizing two complementary cross-coupled transistor pairs coupled to the first and second coupling nodes;
• and
• selectively varying the duration of the regeneration interval to thereby vary an exponential gain of the exponential amplifying.