US5650608A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for generating ratiometric control signals
Assignee: TV Interactive Data Corp
•
Filing: 1994-12-19
•
Granted: 1997-07-22
•
Expires: 2014-12-19
Abstract
Abstract A ratiometric sensor is formed of a first photodiode connected in series with an electronic component, such as a second photodiode or a resistor, between a source of first voltage and a source of second voltage. The ratiometric sensor supplies a "ratiometric voltage" on a ratiometric sensor output line that is connected to a junction between the first photodiode and the electronic component. The ratiometric voltage is proportional to the ratio of the equivalent resistance of the first photodiode to the sum of the equivalent resistances of the first photodiode and the electronic component. A ratiometric sensor that uses a photodiode and a resistance has a large dynamic range because the ratiometric voltage can vary between the first voltage and the second voltage. A ratiometric sensor that uses two photodiodes is less sensitive to noise than a conventional circuit that uses a single photodiode, because noise can get canceled from the numerator and denominator of the ratio. The ratiometric signal can be digitized by an analog-to-digital converter that can include, for example, a 555 timer, a Darlington transistor or a combination of a resistor and a capacitor.
Inventors
- 👤 Peter M. Redford
- 👤 Donald S. Stern
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:09
CPC Classifications
G; G01; G01C; G01C9/00; G01C9/02; G01C9/06; A; A63; A63F; A63F13/00; A63F13/20; A63F13/21; A63F13/213; A63F13/24; A63F13/40; G01C9/18; G01C9/24; G01C9/36; G01D; G01D5/00; G01D5/26; G05; G05G; G05G9/00; G05G9/02; G05G9/04; G05G9/047; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/0202; G06F3/021; G06F3/023; G06F3/0231; G06F3/03; G06F3/033; G09; G09B; G09B9/00; G09B9/02; G09B9/04; G09B9/08; G09B9/28; H; H03; H03F; H03F3/00; H03F3/04; H03F3/08; A63F2300/00; A63F2300/10; A63F2300/1006; A63F2300/1037; A63F2300/1043; A63F2300/1087; H01; H01H; H01H9/00; H01H9/02; H01H9/0214; H01H9/0235
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
148 words
A circuit comprising: a ratiometric sensor comprising a signal sensor, a first reference voltage line, a second reference voltage line and a ratiometric sensor output line, said ratiometric sensor having a first equivalent resistance between said first reference voltage line and said ratiometric sensor output line, said ratiometric sensor further having a second equivalent resistance between said second reference voltage line and said ratiometric sensor output line; and a voltage controlled current amplifier consisting essentially of: a pnp transistor having a base, a collector and an emitter, said base being coupled to said ratiometric sensor output line; a first resistor coupled between said first reference voltage line and said emitter to thereby limit current supplied at said collector; and a second resistor coupled between said first reference voltage line and said collector to thereby allow current to be supplied at said collector when said pnp transistor is off.
Claim 2
Dependent Claim
148 words
A circuit comprising: a ratiometric sensor comprising a signal sensor, a first reference voltage line, a second reference voltage line and a ratiometric sensor output line, said ratiometric sensor having a first equivalent resistance between said first reference voltage line and said ratiometric sensor output line, said ratiometric sensor further having a second equivalent resistance between said second reference voltage line and said ratiometric sensor output line; and a voltage controlled current amplifier consisting essentially of: a pnp transistor having a base, a collector and an emitter, said base being coupled to said ratiometric sensor output line; a first resistor coupled between said first reference voltage line and said emitter to thereby limit current supplied at said collector; and a second resistor coupled between said first reference voltage line and said collector to thereby allow current to be supplied at said collector when said pnp transistor is off.
Claim 3
Dependent Claim
20 words
The circuit of claim 1 further comprising a Darlington pair wherein said pnp transistor is included in said Darlington pair.
Claim 4
Dependent Claim
20 words
The circuit of claim 1 comprising a plurality of ratiometric sensors for detection of movement along a plurality of axes.
Claim 5
Dependent Claim
29 words
The circuit of claim 1 wherein: the first reference voltage line, the second reference voltage line and the collector are coupled to a game port of a personal computer.
Claim 6
Dependent Claim
43 words
The circuit of claim 1 wherein: the ratiometric sensor comprises a potentiometer coupled between the first reference voltage line and the ratiometric sensor output line; and the signal sensor is coupled between the second reference voltage line and the ratiometric sensor output line.
Claim 7
Dependent Claim
13 words
The circuit of claim 5 wherein the signal sensor comprises a photosensitive element.
Claim 8
Dependent Claim
12 words
The circuit of claim 6 wherein the photosensitive element is a photodiode.
Claim 9
Dependent Claim
19 words
The circuit of claim 7 wherein a cathode of the photodiode is coupled to the ratiometric sensor output line.
Claim 10
Dependent Claim
23 words
The circuit of claim 5 further comprising a light emitting diode, wherein the light emitting diode generates light incident on the photosensitive element.
Claim 11
Dependent Claim
34 words
The circuit of claim 9 wherein the light emitting diode has two terminals: a first terminal coupled to the first reference voltage line; and a second terminal coupled to the second reference voltage line.
Claim 12
Dependent Claim
44 words
The circuit of claim 1 wherein: the ratiometric sensor comprises an electronic component coupled between the first reference voltage line and the ratiometric sensor output line; and the signal sensor is coupled between the second reference voltage line and the ratiometric sensor output line.
Claim 13
Dependent Claim
13 words
The circuit of claim 11 wherein the signal sensor comprises a photosensitive element.
Claim 14
Dependent Claim
12 words
The circuit of claim 12 wherein the photosensitive element is a photodiode.
Claim 15
Dependent Claim
19 words
The circuit of claim 13 wherein a cathode of the photodiode is coupled to the ratiometric sensor output line.
Claim 16
Dependent Claim
23 words
The circuit of claim 12 further comprising a light emitting diode, wherein the light emitting diode generates light incident on the photosensitive element.
References Cited (Backward Citations)
SU154030A1
Cited
US2415168A
Cited
US3360653A
Cited
US3371424A
Cited
US3569717A
Cited
US3863067A
Cited
US4040743A
Cited
US4154000A
Cited
US4148014A
Cited
SU800637A1
Cited
US4316155A
Cited
US4430526A
Cited
US4514732A
Cited
DE3236436C1
Cited
DE3303103A1
Cited
US4701048A
Cited
US4565999A
Cited
US4594562A
Cited
US4866602A
Cited
FI841864L
Cited
US4651023A
Cited
US4755801A
Cited
US4682159A
Cited
NL8500817A
Cited
SU1244489A1
Cited
US4642459A
Cited
US4677428A
Cited
US4712885A
Cited
US4787051A
Cited
US4868896A
Cited
US4746879A
Cited
US4839838A
Cited
US4939482A
Cited
US4862172A
Cited
US5363120A
Cited
US5068645A
Cited
US5142655A
Cited
WO1990013792A1
Cited
US5115236A
Cited
US4864647A
Cited
US4883926A
Cited
US5288078A
Cited
US5045843B1
Cited
US5045843A
Cited
US5166819A
Cited
US5063376A
Cited
US5013926A
Cited
US5117099A
Cited
US5097353A
Cited
GB2238382A
Cited
US5059958A
Cited
US5086197A
Cited
US5096650A
Cited
US5223709A
Cited
US5459489A
Cited
US5355147A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-07-21 | 2001-01-20 | 2001-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-21 | 2005-01-20 | 2005-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-21 | 2009-01-20 | 2009-07-22 | $7700.00 | Window Closed / Lapsed |