Claims
- 1. A network interface circuit for providing voltage isolation and impedance matching between a network and equipment coupled to said network through said network interface circuit comprising:a receive data path coupling data from said network to said equipment; a transmit data path coupling data from said equipment to said network; a Σ/Δ analog-to-digital converter coupled to said network in said receive data path; a first capacitive coupler coupled in said receive data path between said Σ/Δ analog-to-digital converter and said equipment wherein Σ/Δ modulated data crosses said first capacitive coupler; a Σ/Δ digital-to-analog converter coupled to said network in said transmit data path; and a second capacitive coupler coupled in said transmit data path between said Σ/Δ digital-to-analog converter and said equipment wherein Σ/Δ modulated data crosses said second capacitive coupler.
- 2. A network interface circuit as set forth in claim 1 wherein said Σ/Δ A analog-to-digital converter generates a 1-bit digital output data stream from analog form data received from said network and said Σ/Δ digital-to-analog converter converts a 1-bit digital input stream into analog form.
- 3. A network interface circuit as set forth in claim 1 wherein said transmit data path and said receive data path carry differential signals and said first and second capacitive couplers each comprise a pair of couplers.
- 4. A method for providing voltage isolation and impedance matching between a network and equipment coupled to said network, said method comprising the steps of:converting analog data received from said network to Σ/Δ data; transmitting said received Σ/Δ data across a first capacitive coupling to said equipment; transmitting Σ/Δ data transmitted from said equipment across a second capacitive coupling; and converting said transmitted ΣΔ data to analog data.
- 5. A method as set forth in claim 4 wherein said first converting step comprises performing a Σ/Δ analog-to-digital conversion on said data received from said network and said second converting step comprises performing a Σ/Δ digital-to-analog conversion on said data transmitted from said receiver.
- 6. A method as set forth in claim 5 wherein;said step of converting analog data received from said network to Σ/Δ data comprises generating a 1-bit digital output data stream; and said step of converting said Σ/Δ data transmitted from said equipment comprises converting 1-bit digital data to analog form.
- 7. A method as set forth in claim 4 wherein said data received from said network and said data transmitted from said equipment are differentially driven across said capacitive couplings.
RELATED APPLICATIONS
The present application is a continuation of U.S. patent application number Ser. 09/037,404 filed Mar. 10, 1998, the disclosure of which is incorporated herein by reference.
US Referenced Citations (6)
Continuations (1)
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Number |
Date |
Country |
Parent |
09/037404 |
Mar 1998 |
US |
Child |
09/835741 |
|
US |