EP0431832A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus and method for controlling the operation of a semiconductor device
Assignee: NCR International Inc
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Filing: 1990-11-29
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Granted: —
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Expires: 2010-11-29
Abstract
Abstract A temperature-sensitive semiconductor device, such as a laser diode (10), is protected against damage from overheating by use of a temperature sensor (16) which produces a signal that is digitized and applied to a microprocessor (40). The microprocessor (40) uses a look-up table to determine an appropriate duty cycle for operation of the semiconductor device (10), based upon the temperature of the semiconductor device (10), so as to avoid operating the semiconductor device (10) for a length of time which could produce overheating and damage.
Inventors
- 👤 Stephen John Ames
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 10:53
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/06; H01S5/062; H01S5/06209; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/1913; G05D23/20; H01S5/068; H01S5/06804; H02; H02H; H02H5/00; H02H5/04; H01S5/0617; H01S5/06213; H01S5/06216
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
131 words
Apparatus for controlling the operation of semiconductor device, including driving means (18) adapted to operatively drive said semiconductor device (10), characterized by control means (128) adapted to control the operation of said driving means (18), temperature sensor means (16) adapted to provide an analog signal dependent on the temperature of said semiconductor device (10), analog-to-digital converter means (36) adapted to convert said analog signal to a digital value, and microprocessor means (40) coupled to said analog-to-digital converter means (36) and adapted to select a duty cycle for operation of said semiconductor device (10), dependent on said digital value, said microprocessor means (40) being coupled to said control means (128) to control said control means (128) to cause said driving means (18) to be operated in accordance with the selected duty cycle.
Claim 2
Dependent Claim
38 words
Apparatus according to claim 1, characterized in that a heat sink (14) is provided operatively associated with said semiconductor device, and in that said temperature sensor means (16) is mounted in operative relation to said heat sink (14).
Claim 3
Dependent Claim
33 words
Apparatus according to claim 1 or claim 2, characterized in that said microprocessor means (40) includes a look-up table which stores data representing a plurality of temperature ranges and corresponding duty cycle values.
Claim 4
Dependent Claim
20 words
Apparatus according to any one of the preceding claims, characterized in that said semiconductor device (10) in a laser diode.
Claim 5
Dependent Claim
39 words
Apparatus according to claim 4, characterized in that said laser diode (10) includes a light monitoring device (22) coupled to said driving means (18), which is adapted to maintain the light output of said laser diode (10) substantially constant.
Claim 6
Dependent Claim
37 words
Apparatus according to any one of the preceding claims, characterized in that said microprocessor means (40) is adapted to receive a signal (LASERON/) from said driving means indicating whether or not said semiconductor device (10) is operating.
Claim 7
Independent Claim
86 words
A method for preventing damage to a temperature-sensitive semiconductor device, characterized by the following steps: (a) measuring the temperature of said temperature-sensitive semiconductor device (10) to obtain temperature data; (b) converting said temperature data to digital form; (c) loading the digital temperature data into a microprocessor (40); (d) using said digital temperature data in the microprocessor (40) to determine a duty factor; and (e) determining the operating time for said semiconductor device (10) during a cycle by multiplying the total cycle time by the duty factor.
Claim 8
Dependent Claim
75 words
A method according to claim 7, characterized by the following additional steps: (f) determining whether the system using the semiconductor device (10) has been triggered to an "on" state; (g) if so, generating a power signal to cause said semiconductor device (10) to be operated during that portion of an operating cycle determined by step (e); and (h) determining whether the operating cycle is complete and allowing no retriggering until said cycle has been completed.
Claim 9
Dependent Claim
20 words
A method according to claim 7 or claim 8, characterized in that said semiconductor device (10) is a laser diode.
Claim 10
Independent Claim
36 words
A method according to any one of claims 7 to 9, characterized in that the determination of the operating time for said semiconductor device (10) in step (e) is accomplished by use of a look-up table.
References Cited (Backward Citations)
No citation records indexed.
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