Yi C Cheng

US Patent:

6377666, Apr 23, 2002

Filed:

Oct 29, 1998

Appl. No.:

09/181557

Inventors:

Yi Cheng - San Jose CA
Zhenhua Liu - Sunnyvale CA

Assignee:

Legerity - Austin TX

International Classification:

H04M 1100

US Classification:

379 9306, 37939902

Abstract:

A transmitter within a line driver circuit is configured to supply data pulses over existing residential wiring. The transmitter is implemented in a CMOS integrated circuit. The transmitter comprises three stages: a front-end digital/analog convertor (DAC), an intermediate DAC, and a current amplifier. The first stage dictates whether the output signal is in high power mode or low power mode. The intermediate DAC, as the second stage, controls the waveform shape and tunes the edge rate, thereby outputting a positive current signal and a negative current signal. The final stage amplifies these current signals to yield current signals having a desired waveform shape, power mode, and edge rate.

US Patent:

6633441, Oct 14, 2003

Filed:

Jul 12, 2000

Appl. No.:

09/615062

Inventors:

Yi Cheng - San Jose CA
Steven C. Lam - Cupertino CA

Assignee:

Marvell International, Ltd. - Hamilton

International Classification:

G11B 2736

US Classification:

360 31, 360 46, 360 67

Abstract:

A circuit for measuring signal output of a transducer includes an amplifier having a differential input and a single ended output referenced to a fixed potential. One transducer terminal is coupled through a source follower to an input terminal of the differential input and the other transducer terminal is coupled through a source follower and a resistive element to the other input terminal of the differential input whereby the transducer terminals are isolated from the fixed potential. A voltage to current converter converts the voltage at the single ended output to an output current that is applied to an input branch of a current mirror. A first output branch of the current mirror supplies a current equal to the converter output current to one terminal of the differential input. A second output branch of the current mirror supplies a current equal to the converter output current to the other terminal of the differential input. A third output branch of the current mirror supplies a multiple of the converter output current to a resistive element having a terminal connected to the fixed potential.

US Patent:

6771750, Aug 3, 2004

Filed:

Oct 29, 1998

Appl. No.:

09/181559

Inventors:

Colin Nayler - Sunnyvale CA
Phil Keller - Fremont CA
Oikwan Tsang - San Jose CA
Hung Vo - San Jose CA
Dennis Lau - Fremont CA
Yi Cheng - San Jose CA
Zhen-Hua Liu - Sunnyvale CA

Assignee:

Advanced Micro Devices, Inc. - Sunnyvale CA

International Classification:

H04L 2503

US Classification:

379 9301, 375318

Abstract:

A physical layer transceiver of a home network station connected to a telephone medium has an architecture enabling adaptation of detection circuitry based on received network signals to enable reliable recovery of data signals. The physical layer transceiver includes an input amplifier that amplifies network signals according to one of 128 gain settings set by a receiver gain control signal. A signal conditioning circuit includes an envelope detector configured for outputting an envelope of the amplified received signal, and an energy detector configured for outputting an energy signal of the amplified received signals. The envelope signal and the energy signal are supplied to slicer threshold circuits, configured for outputting noise, peak, data event and energy event signals based on noise threshold, peak threshold, data transition threshold, and energy threshold signals, respectively. A digital controller controls the input amplifier gain and the threshold values, and adjusts the gain and threshold values based on the noise event signal and the peak event signal within an access ID (AID) interval. Hence, the receiver can be optimized on a per-packet basis for receiving network signals by adjusting the receiver portion during the AID preamble phase of the data packet.

US Patent:

6958872, Oct 25, 2005

Filed:

Oct 10, 2003

Appl. No.:

10/683478

Inventors:

Yi Cheng - San Jose CA, US
Steven Lam - Cupertino CA, US

Assignee:

Marvell International Ltd. - Hamilton

International Classification:

G11B027/36
G11B005/02
G11B005/09

US Classification:

360 31, 360 46, 360 67

Abstract:

A circuit for measuring signal output of a transducer includes an amplifier having a differential input and a single ended output referenced to a fixed potential. One transducer terminal is coupled through a source follower to an input terminal of the differential input and the other transducer terminal is coupled through a source follower and a resistive element to the other input terminal of the differential input whereby the transducer terminals are isolated from the fixed potential. A voltage to current converter converts the voltage at the single ended output to an output current that is applied to an input branch of a current mirror. A first output branch of the current mirror supplies a current equal to the converter output current to one terminal of the differential input. A second output branch of the current mirror supplies a current equal to the converter output current to the other terminal of the differential input. A third output branch of the current mirror supplies a multiple of the converter output current to a resistive element having a terminal connected to the fixed potential.

US Patent:

6982582, Jan 3, 2006

Filed:

Jun 23, 2003

Appl. No.:

10/602997

Inventors:

Yi Cheng - San Jose CA, US

Assignee:

Marvell International Ltd. - Hamilton

International Classification:

H03K 3/037
H03K 3/12

US Classification:

327205, 327206, 327 77

Abstract:

An apparatus and method of a programmable hysteresis comparator capable of producing a digital signal in response to differential input signals is disclosed. In one embodiment, the programmable hysteresis comparator includes a hysteresis offset programmable circuit that is operable to selectively provide a hysteresis offset in response to a programmable hysteresis offset control signal. The programmable hysteresis comparator further includes a comparator circuit, which is capable of receiving differential input signals. The hysteresis comparator is operable to output a digital signal in response to differential input signals and the hysteresis offset.

US Patent:

7161911, Jan 9, 2007

Filed:

Mar 15, 2002

Appl. No.:

10/099050

Inventors:

Calvin Fang - Milpitas CA, US
Yi Cheng - San Jose CA, US
William Lo - Cupertino CA, US

Assignee:

Marvell International, Ltd - Hamilton

International Classification:

H04B 1/44
H04L 12/56

US Classification:

370282, 370419

Abstract:

A first network device is provided in communications with a second network device comprising a physical layer device. The physical layer device comprises a transmitter to transmit an autonegotiation signal to the second network device, a receiver to receive a received signal from the second network device, and a controller comprising an autonegotiation controller to set a highest common data rate between the first network device and the second network device. The autonegotiation controller compares the autonegotiation signal and the received signal and selectively prevents the autonegotiation when the autonegotiation signal is the same as the received signal.

US Patent:

7203851, Apr 10, 2007

Filed:

Mar 15, 2002

Appl. No.:

10/098865

Inventors:

William Lo - Cupertino CA, US
Yi Cheng - San Jose CA, US
Leechung Yiu - Fremont CA, US
Calvin Fang - Milpitas CA, US

Assignee:

Marvell International Ltd. - Hamilton

International Classification:

H04Q 5/22

US Classification:

713310, 379307, 379322, 379323, 379413

Abstract:

A first network device supplies power to a second network device in communication therewith. The first network device comprises a physical layer device which includes a pulse generator to generate a test signal comprising n sub-pulses to be transmitted to the second network device, wherein in n being greater than 2. A detector is responsive to the second network device, and a controller is in communication with the detector and the pulse generator. When the detector detects j pulses which are greater than a predetermined threshold, 1≦j

US Patent:

7552348, Jun 23, 2009

Filed:

Apr 2, 2007

Appl. No.:

11/732010

Inventors:

Willaim Lo - Cupertino CA, US
Yi Cheng - San Jose CA, US
Leechung Yiu - Fremont CA, US
Calvin Fang - Milpitas CA, US

Assignee:

Marvell International Ltd. - Hamilton

International Classification:

H04Q 5/22

US Classification:

713310, 713300, 713320, 713321, 713322, 713323, 713324, 713330, 713340, 379322, 379413, 709223, 709238

Abstract:

A first network device comprises first and second transformers that communicate with a second network device. A switch selectively connects power to the first and second transformers. A physical layer device communicates with the first and second transformers and includes a signal generator, a detector, and a controller that communicates with the switch, the signal generator and the detector. The signal generator generates a test signal comprising n sub-pulses, where n is an integer greater than 2. When the detector detects j pulses that are greater than a predetermined threshold, 1≦j