Static information storage and retrieval – Read/write circuit – Signals
Reexamination Certificate
2007-03-06
2007-03-06
Elms, Richard (Department: 2824)
Static information storage and retrieval
Read/write circuit
Signals
C365S189090, C365S195000
Reexamination Certificate
active
10946951
ABSTRACT:
A data processing system (10) has an embedded non-volatile memory (22) that is programmed and erased by use of a high voltage provided by a charge pump (78). In order to prevent the non-volatile memory (22) from being inadvertently programmed or erased during low power supply voltage conditions, the charge pump (78) is disabled and discharged when the power supply voltage drops below a predetermined value. This is accomplished by enabling a low voltage detect circuit (110) in response to a program or erase operation being initiated. A control register (76) will provide a high voltage enable signal to the charge pump (78) only when a power supply valid signal is received. In another embodiment, the low voltage detect circuit (110) may be enabled by another condition to protect the data processing system (10) from an authorized access.
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Espinor George L.
Morton Bruce L.
Sibigtroth James M.
Wood Michael C.
Clingan, Jr. James L.
Elms Richard
Freescale Semiconductor Inc.
Hill Daniel D.
Nguyen Hien N
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