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公开(公告)号：AU2887677A
公开(公告)日：1979-03-22
申请号：AU2887677
申请日：1977-09-16
Applicant: IBM
Inventor： CROISIER ALAIN , JACQUART CHRISTIAN
Abstract: A circuit for interfacing an AF line to a central unit makes use of an RF transformer Tr. Said transformer is so arranged that the source AF signal to be transmitted modulates an RF carrier generated in a primary winding of the transformer and the resulting modulated signal in the secondary winding is demodulated before being transmitted to a line which is thereby linked to the source.
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公开(公告)号：DE2741681A1
公开(公告)日：1978-04-06
申请号：DE2741681
申请日：1977-09-16
Applicant: IBM
Inventor： CROISIER ALAIN , JACQUART CHRISTIAN
Abstract: A circuit for interfacing an AF line to a central unit makes use of an RF transformer Tr. Said transformer is so arranged that the source AF signal to be transmitted modulates an RF carrier generated in a primary winding of the transformer and the resulting modulated signal in the secondary winding is demodulated before being transmitted to a line which is thereby linked to the source.
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公开(公告)号：DE69019746D1
公开(公告)日：1995-06-29
申请号：DE69019746
申请日：1990-08-29
Applicant: IBM
Inventor： FERMIER YVAN , FERRY MICHEL , JACQUART CHRISTIAN , VACHEE PIERRE
Abstract: The overload protection circuit 12 comprises a resistor bridge 20 with a low impedance sensing resistor r and high impedance resistors R1 to R4 which generates voltages Va and Vb at the inputs 32 and 34 of a comparator 22. Voltage Vb depend upon the value of the load current so that the comparator provides at its output 36 a control signal for opening the switching device 24 comprising a field effect transistor when the load current exceeds a maximum value. Resistor R5 reinforces the effect of the control signal. This circuit can be used in a system which comprises a central power supply unit 8 which powers a plurality of devices such as 4. The status of the circuit 12 is reported to the system 8 though line 14 and circuit 12 comprises a control circuit 26 which is responsive to set and reset control signals on lines 14 and 18 from the unit 8 to close or open the switch 26.
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Patent Agency Ranking
公开(公告)号：DE3587950D1
公开(公告)日：1995-01-12
申请号：DE3587950
申请日：1985-12-30
Applicant: IBM
Inventor： CZARNIAK JEAN-CHRISTOPHE , JACQUART CHRISTIAN , FERRY MICHEL FRANCOIS
Abstract: A digital-Analog Converter for converting an N-bit digital word into its analog representation including means for splitting the N bits into n sections of N/n bits each. For instance a 12-bit word is split into an odd section and an even section which are processed independently and in parallel. This results in two partial results, Vi and Vp respectively representative of the odd and even bit sections. The last step of the conversion is the action (9) of the two partial results Vi and Vp to provide the analog representation of the 12-bit word. Few operators are required to process each section because each bit is converted sequentially. This provides a low cost, compact and simple converter ; moreover, since few operators are required, it may be advantageous to use high precision operators such as disclosed further on.
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15.发明专利
公开(公告)号：CA1329831C
公开(公告)日：1994-05-24
申请号：CA577546
申请日：1988-09-15
Applicant: IBM
Inventor： FERRY MICHEL , JACQUART CHRISTIAN
Abstract: Conversion system for performing either an analog-to-digital A/D conversion associated with an amplification step or either a digital-to-analog D/A conversion associated with an attenuation step. The system includes means (115) for receiving a input digital word to be processed, i.e. converted into analog and then attenuated, and means (165) for receiving an input analog value to be processed, i.e. amplified for scaling purpose and then converted into digital. It also includes an digital-to-analog D/A converter (110), an attenuator (120) for attenuating the analog output of D/A converter (110), and a comparator (150) for comparing the value of the input analog value to be processed and the output of said attenuator (120). The processing of the D/A-attenuation process is performed by means of both D/A converter (110) and attenuator (120). In order to achieve the A/D-amplification process, the system further includes means (140) for generating a sequence of digital words to the D/A converter (110), and means (220) for storing among this sequence, the digital value that minimizes the difference between both input of comparator (150). This digital value is extracted as being the digital representation of the amplified analog input value. Since both A/D-amplification and D/A-attenuation processings involve the same physical components, both processing have transfer function exactly inverse of one another. The typical use of this circuit is in echo cancellation technique. Fig. 1
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公开(公告)号：DE3778702D1
公开(公告)日：1992-06-04
申请号：DE3778702
申请日：1987-10-30
Applicant: IBM
Inventor： FERRY MICHEL , JACQUART CHRISTIAN
Abstract: The signal converter has a digital-to-analogue converter (110) which feeds an attenuator (120) output is compared (150) with the analogue input (165) retained by a sample-and-hold circuit (160). The result of the comparison is forward (175) to the control logic which includes a successive approximation register (276) and NAND gates (221-228) between digital word storage registers (210,220). For the analogue-to-digital conversion, a sequence of digital words is generated and the digital value minimising the difference between the two inputs to the comparator (150) is extracted as being digital representation of the amplified input.
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公开(公告)号：AU4368385A
公开(公告)日：1986-01-02
申请号：AU4368385
申请日：1985-06-14
Applicant: IBM
Inventor： BONNET YVES AIME , JACQUART CHRISTIAN
Abstract: The circuit of the present invention detects variations of a current IL flowing in a telephone line LL. A low-value resistor r is connected in series with line LL. A constant voltage generator is connected across this resistor. The current Is applied to resistor r by the contant voltage generator varies as a function of IL. This being so, a measurement of the variations of Is will reflect variations of IL and, therefore, can be used to detect both amplitude and directional variations of IL.
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公开(公告)号：DE2455584A1
公开(公告)日：1975-07-03
申请号：DE2455584
申请日：1974-11-23
Applicant: IBM
Inventor： BESSEYRE JACQUES , JACQUART CHRISTIAN , MARIJON JEAN-LOUIS
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