EP0420390A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
PLD including configuration memory with backup power supply, and method of supplying power to a PLD with configuration memory
Assignee: STMicroelectronics lnc USA
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Filing: 1990-06-29
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Granted: —
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Expires: 2010-06-29
Abstract
Abstract A programmable logic integrated circuit device utilizes volatile memory elements such as SRAM (62) for retaining configuration information. A circuit (66) is provided as part of the device for detecting loss of power on a supply input pin (64). When power loss is detected, a backup voltage supply (70), packaged with the programmable logic device as a unit, is connected thereto. The backup power is used to supply voltage only to those portions of the device having volatile memory elements containing configuration information. Backup power is not provided to input and output buffers (74,76) of the device, thereby preventing excess loads being placed upon the backup device because of events which may occur external to the programmable logic device.
Inventors
- 👤 Randy Charles Steele
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 01:31
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/02; H03K19/173; H03K19/177; H03K19/17748; H03K19/17772; G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/41; G11C16/00; G11C16/02; G11C5/00; G11C5/14; G11C5/141; H03K19/17704; H03K19/1776; H10; H10B; H10B69/00
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
85 words
A programmable logic integrated circuit device, comprising: a plurality of input/output buffers; a plurality of memory elements for storing configuration information; a power loss detect circuit connected to a device supply voltage input; and a backup power supply connected to said power loss detect circuit; wherein, when said power loss detect circuit detects a power loss on the supply voltage input, said backup power supply is switched to provide power to said memory elements, and wherein backup power is not supplied to said input/output buffers.
Claim 2
Dependent Claim
85 words
A programmable logic integrated circuit device, comprising: a plurality of input/output buffers; a plurality of memory elements for storing configuration information; a power loss detect circuit connected to a device supply voltage input; and a backup power supply connected to said power loss detect circuit; wherein, when said power loss detect circuit detects a power loss on the supply voltage input, said backup power supply is switched to provide power to said memory elements, and wherein backup power is not supplied to said input/output buffers.
Claim 3
Dependent Claim
18 words
The device of Claim 1, wherein said backup power supply comprises a battery integrally packaged with the device.
Claim 4
Dependent Claim
37 words
The device of Claim 1, wherein said input/output buffers can be individually configured to function as either input or output buffers, and wherein said plurality of memory elements comprises latches for storing configuration information for said buffers.
Claim 5
Dependent Claim
20 words
The device of Claim 1, wherein said plurality of memory elements comprises random access memory configured to perform logic functions.
Claim 6
Dependent Claim
28 words
The device of Claim 4, wherein said plurality of memory elements further comprises random access memory which can be written to an read from during normal device operation.
Claim 7
Dependent Claim
23 words
The device of Claim 4, wherein said plurality of memory elements further comprises configuration bits for controlling the operation of programmable switching matrices.
Claim 8
Dependent Claim
84 words
A power supply for a programmable logic device having input/output buffers and volatile memory elements, comprising: a power supply input pin for supplying power to the device; a battery housed with the device as an integral unit; and power loss detect circuitry connected to said input pin and to said battery, wherein said battery is electrically connected to the volatile memory elements when power loss is detected by said power loss detect circuitry, and wherein said battery is electrically isolated from the input/output buffers.
Claim 9
Dependent Claim
84 words
A power supply for a programmable logic device having input/output buffers and volatile memory elements, comprising: a power supply input pin for supplying power to the device; a battery housed with the device as an integral unit; and power loss detect circuitry connected to said input pin and to said battery, wherein said battery is electrically connected to the volatile memory elements when power loss is detected by said power loss detect circuitry, and wherein said battery is electrically isolated from the input/output buffers.
Claim 10
Dependent Claim
17 words
The supply of Claim 7, wherein the volatile memory elements include configuration bits for the input/output buffers.
Claim 11
Dependent Claim
19 words
The supply of Claim 7, wherein the volatile memory elements comprise random access memory configured to perform logic functions.
Claim 12
Dependent Claim
27 words
The supply of Claim 9, wherein the volatile memory elements further include configuration bits for programmable switching matrices used to interconnect portions of the random access memory.
Claim 13
Independent Claim
67 words
A method for supplying power to a programmable logic device having input/output buffers and configuration memory elements, comprising the steps of: when a sufficient supply voltage is available on a supply input, providing power to the entire device from such supply voltage; when the supply voltage is insufficient, providing power from a backup power supply to the configuration memory elements without providing power to the input/output buffers.
Claim 14
Independent Claim
67 words
A method for supplying power to a programmable logic device having input/output buffers and configuration memory elements, comprising the steps of: when a sufficient supply voltage is available on a supply input, providing power to the entire device from such supply voltage; when the supply voltage is insufficient, providing power from a backup power supply to the configuration memory elements without providing power to the input/output buffers.
Claim 15
Dependent Claim
49 words
The method of Claim 11, wherein said backup power supplying step comprises the steps of: providing a power loss detect circuit connected to the supply input; and when an insufficient supply voltage occurs, supplying power to the configuration memory elements from a backup battery housed integrally with the device.
References Cited (Backward Citations)
No citation records indexed.
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