US5339270A
Expired / Lapsed
US
⏱️ 0.0 years remaining
AC drain voltage charging source for PROM devices
Assignee: Callahan Cellular LLC
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Filing: 1993-06-23
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Granted: 1994-08-16
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Expires: 2013-06-23
Abstract
Abstract A method for programming a programmable read only memory (PROM) is useful for a PROM which has a source, a drain and a control gate. A DC signal is placed on the control gate. For example, the DC signal has a voltage of approximately 5 volts. An AC signal is placed on the drain. The AC signal, for example, oscillates between approximately 0 volts and 5 volts and has a frequency of at least 100 Megahertz. As a result, charges tunnel through a tunnel oxide region to an floating gate, thus programming the PROM.
Inventors
- 👤 Chun Jiang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:28
CPC Classifications
G; G11; G11C; G11C16/00; G11C16/02; G11C16/06; G11C16/10; G11C16/12
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
104 words
A method for programming a programmable read only memory having a source, a drain, a floating gate and a control gate, wherein the floating gate region is separated from the drain by a tunnel oxide region, the method comprising the steps of: (a) placing a DC signal on the control gate; and (b) placing an oscillating signal on the drain, wherein an oscillating frequency and a fall time for the oscillating signal are selected so that upon the oscillating signal reaching a minimum voltage, hot electrons at the drain tunnel through the tunnel oxide region to the floating gate, thereby charging the floating gate.
Claim 2
Independent Claim
104 words
A method for programming a programmable read only memory having a source, a drain, a floating gate and a control gate, wherein the floating gate region is separated from the drain by a tunnel oxide region, the method comprising the steps of: (a) placing a DC signal on the control gate; and (b) placing an oscillating signal on the drain, wherein an oscillating frequency and a fall time for the oscillating signal are selected so that upon the oscillating signal reaching a minimum voltage, hot electrons at the drain tunnel through the tunnel oxide region to the floating gate, thereby charging the floating gate.
Claim 3
Dependent Claim
20 words
A method as in claim 1 wherein, in step (a) the DC signal has a voltage of approximately 5 volts.
Claim 4
Dependent Claim
29 words
A method as in claim 1 wherein in step (b), the oscillating signal oscillates between approximately 0 volts and 5 volts and has a frequency greater than 100 Megahertz.
Claim 5
Dependent Claim
29 words
A method as in claim 1 wherein, in step (b), the oscillating signal fall time from high voltage to low voltage is less than or equal to 0.1 pico-second.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-08-15 | 1998-02-14 | 1998-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-15 | 2002-02-14 | 2002-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-15 | 2006-02-14 | 2006-08-16 | $7700.00 | Window Closed / Lapsed |