# US 7,411,853 B2 · Volatile memory elements with elevated power supply levels for programmable logic device integrated circuits > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,411,853 B2 - Document ID: US7411853B2 - Status: Granted - Kind: B2 - Application number: 11/282,437 - Filed: 2005-11-17 - Published: 2007-05-17 - Granted: 2008-08-12 - Earliest claimed: 2005-11-17 - Assignees: Altera Corporation - Inventors: Lin-Shih Liu; Mark T. Chan; Toan D. Do - Web page: https://patentgrep.com/patent/US7411853B2 ## CPC - G11C 5/14: Power supply arrangements {, e.g. power down, chip selection or deselection, layout of wirings or power grids, or multiple supply levels} - G05F 1/465: {Internal voltage generators for integrated circuits, e.g. step down generators} - G11C 11/413: Auxiliary circuits, e.g. for addressing, decoding, driving, writing, sensing, timing or power reduction - H03K 19/1776: for memories - H03K 19/17784: for supply voltage - H03K 19/17792: for operating speed - G11C: STATIC STORES (semiconductor memory devices H10B) - G05F: SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) ## Abstract Integrated circuits are provided that have volatile memory elements. The memory elements produce output signals. The integrated circuits may be programmable logic device integrated circuits containing programmable core logic including transistors with gates. The core logic is powered using a core logic power supply level defined by a core logic positive power supply voltage and a core logic ground voltage. When loaded with configuration data, the memory elements produce output signals that are applied to the gates of the transistors in the core logic to customize the programmable logic device. The memory elements are powered with a memory element power supply level defined by a memory element positive power supply voltage and a memory element ground power supply voltage. The memory element power supply level is elevated with respect to the core logic power supply level. ## Claims ### Claim 1 A programmable logic device integrated circuit comprising: a region of programmable core logic including transistors, wherein the core logic is powered at a core logic power supply level; and an array of volatile memory elements powered with a memory element power supply level that is greater than the core logic power supply level, wherein the memory elements are loaded with configuration data and provide corresponding output signals that are applied to respective gates of the transistors, wherein the transistors comprise p-channel metal-oxide-semiconductor power-down transistors, some of which are selectively turned off to power down portions of circuitry on the integrated circuit. ### Claim 2 (depends on 1) The programmable logic device integrated circuit defined in claim 1 further comprising first and second memory element power supply terminals in each memory element, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided to each memory element using a memory element positive power supply voltage applied to the first memory element power supply terminal and a memory element ground applied to the second memory element power supply terminal, and wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element positive power supply voltage that is greater than the core logic positive power supply voltage. ### Claim 3 (depends on 1) The programmable logic device integrated circuit defined in claim 1 further comprising first and second memory element power supply terminals in each memory element, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided to each memory element using a memory element positive power supply voltage applied to the first memory element power supply terminal and a memory element ground applied to the second memory element power supply terminal, and wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element ground power supply voltage that is less than the core logic ground power supply voltage. ### Claim 4 (depends on 1) The programmable logic device integrated circuit defined in claim 1 further comprising first and second memory element power supply terminals in each memory element, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided to each memory element using a memory element positive power supply voltage applied to the first memory element power supply terminal and a memory element ground applied to the second memory element power supply terminal, and wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element positive power supply voltage that is greater than the core logic positive power supply voltage and using a memory element ground power supply voltage that is less than the core logic ground power supply voltage. ### Claim 5 (depends on 1) The integrated circuit defined in claim 1 wherein each memory element comprises two cross-coupled inverters, wherein each inverter comprises a p-channel metal-oxide-semiconductor transistor and an n-channel metal-oxide-semiconductor transistor, wherein the p-channel metal-oxide-semiconductor transistor and an n-channel metal-oxide-semiconductor transistor in each inverter are connected in series between a positive power supply terminal at which the memory element positive power supply voltage is supplied and a ground terminal at which the memory element ground power supply voltage is supplied, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided using a memory element positive power supply voltage and a memory element ground, and wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element positive power supply voltage that is greater than the core logic positive power supply voltage. ### Claim 6 (depends on 1) The integrated circuit defined in claim 1 wherein each memory element comprises two cross-coupled inverters, wherein each inverter comprises a p-channel metal-oxide-semiconductor transistor and an n-channel metal-oxide-semiconductor transistor, wherein the p-channel metal-oxide-semiconductor transistor and an n-channel metal-oxide-semiconductor transistor in each inverter are connected in series between a positive power supply terminal at which the memory element positive power supply voltage is supplied and a ground terminal at which the memory element ground power supply voltage is supplied, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided using a memory element positive power supply voltage and a memory element ground, and wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element ground power supply voltage that is less than the core logic ground power supply voltage. ### Claim 7 (depends on 1) The integrated circuit defined in claim 1 wherein each memory element comprises two cross-coupled inverters, wherein each inverter comprises a p-channel metal-oxide-semiconductor transistor and an n-channel metal-oxide-semiconductor transistor, wherein the p-channel metal-oxide-semiconductor transistor and an n-channel metal-oxide-semiconductor transistor in each inverter are connected in series between a positive power supply terminal at which the memory element positive power supply voltage is supplied and a ground terminal at which the memory element ground power supply voltage is supplied, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided using a memory element positive power supply voltage and a memory element ground, and wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element positive power supply voltage that is greater than the core logic positive power supply voltage and using a memory element ground power supply voltage that is less than the core logic ground power supply voltage. ### Claim 8 (depends on 1) The integrated circuit defined in claim 1, wherein the transistors comprise n-channel metal-oxide-semiconductor pass transistors. ### Claim 9 A programmable logic device integrated circuit comprising: a region of programmable core logic including transistors, wherein the core logic is powered at a core logic power supply level; and an array of volatile memory elements powered with a memory element power supply level that is greater than the core logic power supply level, wherein the memory elements are loaded with configuration data and provide corresponding output signals that are applied to respective gates of the transistors, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided using a memory element positive power supply voltage and a memory element ground, wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element positive power supply voltage that is greater than the core logic positive power supply voltage and using a memory element ground power supply voltage that is less than the core logic ground power supply voltage, wherein each memory element comprises an address transistor controlled by an address line with associated address signals, and wherein the associated address signals have logic high levels equal to the memory element positive power supply voltage and logic low levels equal to the memory element ground power supply voltage. ### Claim 10 (depends on 9) The integrated circuit defined in claim 9, wherein each memory element is connected by its address transistor to a data line with associated data signals. ### Claim 11 (depends on 9) The integrated circuit defined in claim 9, wherein each memory element comprises a clear transistor controlled by a clear line with associated clear signals, and wherein the associated clear signals have logic high levels equal to the memory element positive power supply voltage and logic low levels equal to the memory element ground power supply voltage. ### Claim 12 (depends on 9) The integrated circuit defined in claim 9, wherein each memory element comprises a clear transistor controlled by a clear line with associated clear signals, wherein the associated clear signals have logic high levels equal to the memory element positive power supply voltage and logic low levels equal to the memory element ground power supply voltage, wherein each memory element is connected by its address transistor to a data line with associated data signals, and wherein the associated data signals have logic high levels equal to the memory element positive power supply voltage and logic low levels equal to the memory element ground power supply voltage. ### Claim 13 A programmable logic device integrated circuit comprising: a region of programmable core logic including transistors, wherein the core logic is powered at a core logic power supply level; and an array of volatile memory elements powered with a memory element power supply level that is greater than the core logic power supply level, wherein the memory elements are loaded with configuration data and provide corresponding output signals that are applied to respective gates of the transistors, wherein the core logic power supply level is provided using a core logic positive power supply voltage and a core logic ground and wherein the memory element power supply level is provided using a memory element positive power supply voltage and a memory element ground, wherein when the output signals are being provided to the respective gates of the transistors, the memory elements are being powered using a memory element positive power supply voltage that is greater than the core logic positive power supply voltage and using a memory element ground power supply voltage that is less than the core logic ground power supply voltage, wherein each memory element comprises a clear transistor controlled by a clear line with associated clear signals, and wherein the associated clear signals have logic high levels equal to the memory element positive power supply voltage and logic low levels equal to the memory element ground power supply voltage. ### Claim 14 A method for using volatile memory elements on a programmable logic device integrated circuit that contains programmable core logic, comprising: powering the programmable core logic at a core power supply level; powering the volatile memory elements with a memory element power supply level that is elevated with respect to the core power supply level, wherein powering the programmable core logic with the core power supply level comprises powering the programmable core logic using a core logic positive power supply voltage and a core logic ground power supply voltage, wherein powering the memory elements with the memory element power supply level comprises powering the memory elements using a memory element positive power supply voltage and a memory element ground power supply voltage, wherein the memory element positive power supply voltage is greater than the core logic positive power supply voltage, wherein the memory element ground power supply voltage is less than the core logic ground power supply voltage, and wherein each memory element has an n-channel metal-oxide-semiconductor address transistor controlled by an address line; and asserting and deasserting the address line to load data into the memory elements, wherein asserting the address line comprises raising the address line to the memory element positive power supply voltage and wherein deasserting the address line comprises lowering the address line to the memory element ground power supply voltage. ### Claim 15 (depends on 14) The method defined in claim 14 further comprising: asserting and deasserting a clear line to clear the memory elements before data loading, wherein asserting the clear line comprises raising the clear line to the memory element positive power supply voltage and wherein deasserting the clear line comprises lowering the clear line to the memory element ground power supply voltage.