Method and apparatus for detection of load impedance modulation in a transformer circuit
AssigneeMaxim Integrated Products, Inc.
InventorsKiyoshi Fukahori, Russell Hershbarger
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Abstract
A method and apparatus for detection of load impedance modulation as a result of communication of data from the secondary to the primary side of a transformer are presented. The load impedance on the secondary of the transformer barrier is modulated differentially using data to be communicated across the barrier. A detection circuit on the primary side isolates the load current from the magnetizing current in the primary. The load current is subsequently integrated over two consecutive Manchester periods and the integrated value from the first Manchester period is compared against that of the second period thereby recovering the receive data.
Claims8
An apparatus for detecting a load impedance in a transformer comprising:
- a transformer having a primary side and a secondary side;
- a first circuit component coupled to said secondary side of said transformer configured to differentially modulate a load impedance on said secondary side of said transformer by:
- obtaining a data stream for communication from said secondary side to said primary side of said transformer;
- converting said data stream to a differential bitstream;
- and
- modulating said load impedance on said secondary side using said differential bitstream;
- and
- a second circuit coupled to said primary side of said transformer configured to detect said modulated load impedance by differentially integrating a load current on said primary side of said transformer.
A method for detecting a load impedance in a transformer having a primary side and a secondary side comprising:
- obtaining a data stream for communicating from said secondary side to said primary side of said transformer;
- converting said data stream to a differential bitstream;
- modulating said load impedance on said secondary side of said transformer using said differential bitstream;
- and
- detecting said modulated load impedance by differentially integrating a load current on said primary side of said transformer.
Dependencies are inferred from the claim text.