US5347197A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Display device having a display tube including a cold cathode and a current mirror drive circuit for the cold cathode
Assignee: US Philips Corp
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Filing: 1993-03-19
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Granted: 1994-09-13
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Expires: 2013-03-19
Abstract
Abstract A display device having a display tube including a cold cathode, for example a PN emitter (PNE), has the terminals of the PN emitter (PNE) coupled between first terminals of a first (CR1) and a second (CR2) current mirror. The first current repeater (CR1) is connected to an output of an amplifier (AMP) whose feedback input (FI) is connected to second terminals of the first (CR1) and second (CR2) current mirrors.
Inventors
- 👤 Terence Doyle
- 👤 Matheus J. G. Lammers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:22
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/148; G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/26; G05F3/265; H03; H03F; H03F1/00; H03F1/30; H03F1/302
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
126 words
A display device having a display tube including a cold cathode, said display device comprising: amplifying means having a signal input and a feedback input; first current mirror means coupled to said amplifying means and having a first terminal and a second terminal; second current mirror means having an input and an output; said cold cathode having a first end coupled to said first terminal of said first current mirror means, and a second end coupled to said input of said second current mirror means; and feedback means having a first end coupled to said second terminal of said first current mirror means and to said output of said second current mirror means, and a second end coupled to said feedback input of said amplifying means.
Claim 2
Dependent Claim
126 words
A display device having a display tube including a cold cathode, said display device comprising: amplifying means having a signal input and a feedback input; first current mirror means coupled to said amplifying means and having a first terminal and a second terminal; second current mirror means having an input and an output; said cold cathode having a first end coupled to said first terminal of said first current mirror means, and a second end coupled to said input of said second current mirror means; and feedback means having a first end coupled to said second terminal of said first current mirror means and to said output of said second current mirror means, and a second end coupled to said feedback input of said amplifying means.
Claim 3
Dependent Claim
55 words
A display device as claimed in claim 1, wherein said amplifying means have a voltage output coupled to a main terminal of said first current mirror means, while said first terminal of said first current mirror means is an input terminal, and said second terminal of said first current mirror means is an output terminal.
Claim 4
Dependent Claim
40 words
A display device as claimed in claim 1, wherein said amplifying means have a current output coupled to an input of said first current mirror means, said first and second terminals of said first current mirror means being output terminals.
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) | 1997-09-12 | 1998-03-14 | 1998-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-12 | 2002-03-14 | 2002-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-12 | 2006-03-14 | 2006-09-13 | $7700.00 | Window Closed / Lapsed |