EP0242748A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Bipolar/Mos input circuit for photovoltaic detectors
Assignee: Honeywell Inc
•
Filing: 1987-04-11
•
Granted: —
•
Expires: 2007-04-11
Abstract
Abstract A bipolar/MOS input circuit for coupling signals from one of an array of photovoltaic detectors to a CCD or CMOS multiplexer comprises a bipolar transistor (14) having a common base configuration. Current (I s ) produced by the detector is applied to the emitter (16) of the transistor. An insulated well gate (26) is formed adjacent the collector (22) of the transistor. An insulated reference gate (24) is located between the collector (22) and the well gate (26). Voltage applied to the base (20) of the transistor is adjusted so that the magnitude of current, minority carriers, of the semiconductor base, flowing from the collector (22) to the potential well beneath the well gate (26) substantially equals the signal current produced by the photovoltaic detector. The potential well under the well gate can be the first storage well of a CCD multiplexer (26, 28)
Inventors
- 👤 Mark N. Gurnee
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 19:47
CPC Classifications
H; H10; H10D; H10D44/00; H10D44/40; H10D44/45; H10D44/452; H10F; H10F39/00; H10F39/10; H10F39/12; H10F39/15; H10F39/157; H10F39/1575
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
122 words
An input circuit for a photovoltaic detector (18) for producing a detector signal (I S ) ; characterized by a semiconductor substrate (10); a bipolar transistor (14) formed on the substrate (10), said transistor having an emitter (16), a base (20) and a collector (22); circuit means for applying the detector signal (I S ) to the emitter (16) of the bipolar transistor (14); an insulated gate means (24, 26) formed on the substrate (10) adjacent to the collector (22) for forming a potential well within which minority charge carriers flowing from the collector (22) are periodically accumulated; and a multiplexer (26, 28), the minority carriers periodically accumulated in the potential well (V w ) being an input signal to the multiplexer.
Claim 2
Dependent Claim
122 words
An input circuit for a photovoltaic detector (18) for producing a detector signal (I S ) ; characterized by a semiconductor substrate (10); a bipolar transistor (14) formed on the substrate (10), said transistor having an emitter (16), a base (20) and a collector (22); circuit means for applying the detector signal (I S ) to the emitter (16) of the bipolar transistor (14); an insulated gate means (24, 26) formed on the substrate (10) adjacent to the collector (22) for forming a potential well within which minority charge carriers flowing from the collector (22) are periodically accumulated; and a multiplexer (26, 28), the minority carriers periodically accumulated in the potential well (V w ) being an input signal to the multiplexer.
Claim 3
Dependent Claim
43 words
An input circuit according to claim 1, characterized in that the insulated gate means includes a reference gate (24) and a well gate (26), the potential applied to the well gate (26) being greater than the potential applied to the reference gate (24).
Claim 4
Dependent Claim
40 words
An input circuit according to claim 2 or 3, characterized in that the multiplexer (26, 28) is a charge coupled device and the potential well formed by the insulated gate means (26) is the first storage well of the multiplexer.
Claim 5
Dependent Claim
99 words
An input circuit according to claim 1, 2 or 3 for a photovoltaic detector producting a detector signal (I S ), the magnitude of which is proportional to the intensity of incident electromagnetic radiation; characterized in that the well gate forms a potential wall in the substrate (10) under the well gate (26) adjacent the reference gate (24); the reference (24) and well gates (26) are electrically insulated from the substrate; and a CCD multiplexer is formed on the substrate (10), the potential well under the well gate (26) being the source of charge packets transferred by the CCD.
Claim 6
Dependent Claim
73 words
An input circuit according to one of the preceding claims, characterized by means for producing a reference voltage (V ref ) which is connected to the reference gate (24) and means for producing a well voltage (V w ) which is connected to the well gate means (26), whereat the reference voltage (V ref ) connected to the reference gate (24) determines the voltage of the collector (22) of the bipolar transistor (14).
Claim 7
Dependent Claim
23 words
An input circuit according to one of the preceding claims, characterized in that the detector signal (I s ) is an electric current.
Claim 8
Dependent Claim
21 words
An input circuit according to one of the preceding claims, characterized in that the semiconductor substrate (10) is of the p-type.
Claim 9
Dependent Claim
28 words
An input circuit according to one of the preceding claims, characterized in that the bipolar transistor (14) is of the npn type and has a common base configuration.
Claim 10
Dependent Claim
75 words
An input circuit according to claim 8, characterized by means for producing a base voltage (V b ) and for applying the base voltage (V b ) to the base (20) of the bipolar transistor (14), the magnitude of the base voltage causing the current flowing from the collector (22) to the potential well formed by the well gate (26) to substantially equal the detector signal (I s ) produced by the photovoltaic detector (18).
Claim 11
Dependent Claim
33 words
An input circuit according to one of the preceding claims, characterized in that the photovoltaic detector (18) is one of a plurality of detectors lying in the focal plane of a photosensing device.
References Cited (Backward Citations)
US4152715A
Cited
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.