SYSTEM AND METHOD FOR AUTOMATIC DETECTION OF POWER UP FOR A DUAL-RAIL CIRCUIT

摘要

When powering-up or exiting from a sleep mode, the ramping up of various supply voltage nodes may occur at different rates. Thus, in a dual-rail memory circuit, a first voltage rail may be at voltage before a second voltage rail. Such a transient state of operation may lead to current spikes that unnecessarily draw power and introduce undesired inefficiency. An internal sleep signal generation circuit in the dual-rail memory circuit precisely controls an internal sleep signal such that the transition from off or sleep mode to operating mode is set to assure that the supply voltage nodes are close enough to the at-voltage operating level before releasing the sleep mode.

主权项

1. A memory, comprising:
a first voltage node configured to ramp up to a first voltage magnitude; a second voltage node having a second voltage magnitude that is greater than the first voltage magnitude; and a sleep mode generation circuit configured to hold a sleep signal at a first logic value until a ramping voltage at the first voltage node exceeds a threshold voltage and the change the sleep signal to a second logic value.