Memory control with selective retention

A method of controlling data retention in a memory circuit, said method comprising the steps of:

• selectively switching a first supply signal to a respective one of at least two virtual supply lines each shared by a respective one of a plurality of groups of memory cells;
• selectively switching a second supply signal to said respective one of said at least two virtual supply lines;
• controlling said first switching step based on a global activity control signal, used for setting said memory circuit either into a standby state or into an active state, and a first local data retention indication signal allocated to a dedicated group of memory cells;
• and
• controlling said second switching step based on said global activity control signal and a second local data retention indication signal allocated to said dedicated group of memory cells.

An integrated memory circuit comprising:

• a plurality of groups of memory cells;
• at least two virtual supply lines each shared by a respective group of said memory cells;
• at least two first switches configured to selectively switch a first supply signal to a respective one of said at least two virtual supply lines;
• at least two second switches configured to selectively switch a second supply signal to said respective one of said at least two virtual supply lines;
• and
• at least two control circuits configured to receive (i) a global activity control signal used for setting said memory circuit either into a standby or into an active state, (ii) a first local data retention indication signal, and (iii) a second local data retention indication signal,
• wherein said at least two control circuits are configured to:
• control an associated one of said at least two first switches based on said global activity control signal and said first local data retention indication signal;
• and
• control an associated one of said at least two second switches based on said global activity control signal and said second local data retention indication signal.