Invention Grant
- Patent Title: Efficient retention flop utilizing different voltage domain
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Application No.: US16391085Application Date: 2019-04-22
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Publication No.: US11005459B1Publication Date: 2021-05-11
- Inventor: Greg M. Hess , Vivekanandan Venugopal , Victor Zyuban
- Applicant: Apple Inc.
- Applicant Address: US CA Cupertino
- Assignee: Apple Inc.
- Current Assignee: Apple Inc.
- Current Assignee Address: US CA Cupertino
- Agency: Kowert Hood Munyon Rankin and Goetzel PC
- Agent Rory D. Rankin
- Main IPC: H03K3/037
- IPC: H03K3/037 ; G11C19/18 ; H03K3/356

Abstract:
A system and method for efficiently retaining data in sequential elements during power down modes. In various embodiments, a master latch of a flip-flop circuit receives an always-on first power supply voltage, whereas, a slave latch and other surrounding circuitry receives a second power supply voltage capable of being powered down. During a power down mode, circuitry consumes less power while the master latch retains stored data. In some designs, the flip-flop circuit is a level shifting circuit, and the always-on first power supply voltage is less than the second power supply voltage. The master latch uses complex gates with a p-type transistor at the top of a stack of p-type transistors receiving the always-on power supply voltage level on its source terminal and the retained data value on its gate terminal. This top p-type transistor is capable of remaining disabled even when used in a level shifting manner.
Information query
IPC分类: