Jonathan Milton Fredrik Starr

US Patent:

6411131, Jun 25, 2002

Filed:

May 21, 1999

Appl. No.:

09/316421

Inventors:

Michael A. Ang - San Francisco CA
Jonathan E. Starr - Cupertino CA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

G01R 1900

US Classification:

327 52, 327 56

Abstract:

A receiver is provided which quickly and efficiently recognizes signals by including with the receiver a resolving circuit which is coupled to a signal generation circuit which provides a differential current. The resolving circuit is coupled to a latching circuit. The resolving circuit can operate with supply voltage levels as low as one threshold voltage. Also, the signal setup and hold times are inherently vary small due to the high intrinsic bandwidth of the receiver. Other advantages include reduced power consumption, high speed operation, good rejection of input noise and power supply noise, ability to resolve small (e. g. , 1. 0 mVolt) voltage differences, reduced capacitive loading, and the ability to function with a variety of types of drivers, including HSTL, DTL and PECL.

US Patent:

6420913, Jul 16, 2002

Filed:

Sep 20, 1999

Appl. No.:

09/398868

Inventors:

Michael A. Ang - San Francisco CA
Alexander D. Taylor - Olga WA
Jonathan E. Starr - Cupertino CA
Sai V. Vishwanthaiah - Sunnyvale CA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

H03B 100

US Classification:

327108, 327112

Abstract:

A driver capable of launching signals into a transmission line and of terminating signals at a receiver end of the transmission line includes within the driver a circuit for controlling the output impedance and a circuit for controlling the output slew rate. Accordingly, a desired output impedance can be advantageously established and maintained over a wide range of variations in operating conditions, manufacturing processes and output voltage levels. Such a driver also advantageously limits any crowbar current, thereby reducing the overall power consumption of the driver with little, if any, degradation of driver performance. The driver includes a pull up circuit coupled to receive at least one of a plurality of control codes. The pull up circuit includes pull up output circuit and an impedance control buffer circuit, a parallel pull up circuit, the parallel pull up circuit and the pull up output circuit being controllable to adjust the impedance of the pull up circuit. The driver also includes a pull down circuit coupled to receive at least one of the plurality of control codes.

US Patent:

6608506, Aug 19, 2003

Filed:

Mar 20, 2002

Appl. No.:

10/102564

Inventors:

Michael A. Ang - San Francisco CA
Alexander D. Taylor - Olga WA
Jonathan E. Starr - Cupertino CA
Sai V. Vishwanthaiah - Sunnyvale CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

H03B 100

US Classification:

327108, 327112

Abstract:

A driver capable of launching signals into a transmission line and of terminating signals at a receiver end of the transmission line includes within the driver a circuit for controlling the output impedance and a circuit for controlling the output slew rate. Accordingly, a desired output impedance can be advantageously established and maintained over a wide range of variations in operating conditions, manufacturing processes and output voltage levels. Such a driver also advantageously limits any crowbar current, thereby reducing the overall power consumption of the driver with little, if any, degradation of driver performance. The driver includes a pull up circuit coupled to receive at least one of a plurality of control codes. The pull up circuit includes pull up output circuit and an impedance control buffer circuit, a parallel pull up circuit, the parallel pull up circuit and the pull up output circuit being controllable to adjust the impedance of the pull up circuit. The driver also includes a pull down circuit coupled to receive at least one of the plurality of control codes.

US Patent:

63169576, Nov 13, 2001

Filed:

Sep 20, 1999

Appl. No.:

9/399450

Inventors:

Michael A. Ang - San Francisco CA
Alexander D. Taylor - Olga WA
Jonathan E. Starr - Cupertino CA
Sai V. Vishwanthaiah - Sunnyvale CA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

H03K 1716

US Classification:

326 30

Abstract:

A method of controlling impedance of a driver capable of launching signals at a driving end of a transmission line and capable of terminating signals at the receiver end of the transmission line controls the impedance of the driver across process, voltage, and temperature (PVT) variations by selectively enabling and disabling at least one of a plurality of output elements according to an impedance control code. The impedance control code compensates for variations in output impedance due to PVT variations. The method includes selectively enabling and disabling the plurality of output elements so that a direct current impedance of a parallel combination of the plurality of output elements is within a predetermined percentage of the impedance of the transmission line, and sizing the plurality of output elements to account for a predetermined range of PVT conditions, and selectively enabling and disabling the plurality of output elements to allow an impedance of the driver to be approximately equal to the impedance of the transmission line when an output voltage from the driver is approximately half the first supply voltage. The sizing of a plurality of transistors within the plurality of output elements is such that the direct current impedance of a parallel combination of the plurality of output elements is approximately equal to the impedance of the transmission line when the output voltage is half the supply voltage.

US Patent:

62949241, Sep 25, 2001

Filed:

Sep 20, 1999

Appl. No.:

9/399453

Inventors:

Michael A. Ang - San Francisco CA
Alexander D. Taylor - Olga WA
Jonathan E. Starr - Cupertino CA
Sai V. Vishwanthaiah - Sunnyvale CA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

H03K 190185

US Classification:

326 30

Abstract:

A dynamic termination logic driver, the driver capable of launching signals at a driving end of a transmission line and terminating signals at a receiver end of the transmission line, controls slew rate over a wide range of variations in operating conditions, manufacturing processes and output voltage levels. Such a driver also advantageously limits any crowbar current, thereby reducing the overall power consumption of the driver with little, if any, degradation of driver performance. The driver includes a pull up circuit having an impedance, the pull up circuit including a pull up output circuit and a buffer circuit, the pull up output circuit including a parallel pull up circuit, a pull up output control circuit, and a pull up slew rate control circuit, wherein the parallel pull up circuit and the pull up output control circuit are coupled in parallel. The driver also includes a pull down circuit having an impedance, the pull down circuit including at least one pull down output circuit, the at least one pull down output circuit including at least one pull down slew rate control circuit, a parallel pull down circuit and a pull down output control circuit, wherein the parallel pull down circuit and the pull down output control circuit are coupled in parallel. The driver also includes a plurality of output elements within the pull up circuit and the pull down circuit, wherein the plurality of output elements are selectively enabled and disabled with a controlled slew rate.

US Patent:

62817140, Aug 28, 2001

Filed:

May 21, 1999

Appl. No.:

9/316309

Inventors:

Michael A. Ang - San Francisco CA
Jonathan E. Starr - Cupertino CA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

G01R 1900

US Classification:

327 56

Abstract:

A receiver is provided which quickly and efficiently recognizes signals by including with the receiver a resolving circuit which is coupled to a signal generation circuit which provides a differential current. The resolving circuit is coupled to a latching circuit. The resolving circuit can operate with supply voltage levels as low as one threshold voltage. Also, the signal setup and hold times are inherently very small due to the high intrinsic bandwidth of the receiver. Other advantages include reduced power consumption, high speed operation, good rejection of input noise and power supply noise, ability to resolve small (e. g. , 1. 0 m Volt) voltage differences, reduced capacitive loading, and the ability to function with a variety of types of drivers, including HSTL, DTL and PECL.

US Patent:

6297677, Oct 2, 2001

Filed:

Sep 20, 1999

Appl. No.:

9/398872

Inventors:

Michael A. Ang - San Francisco CA
Alexander D. Taylor - Olga WA
Jonathan E. Starr - Cupertino CA
Sai V. Vishwanthaiah - Sunnyvale CA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

H03K 512

US Classification:

327170

Abstract:

A dynamic termination logic driver, one that is capable of launching signals at a driving end of a transmission line and is capable of terminating signals at a receiver end of the transmission line, controls output impedance and includes within the driver an impedance circuit and slew rate control. Accordingly, a desired output impedance can be advantageously established and maintained over a wide range of variations in operating conditions, manufacturing processes and output voltage levels. Such a driver also advantageously limits any crowbar current, thereby reducing the overall power consumption of the driver with little, if any, degradation of driver performance. The driver includes a pull up circuit coupled to receive at least one of a plurality of control codes and the driver also includes a pull down circuit coupled to receive at least one of the plurality of control codes. The output impedance of the driver is further controlled during transitional phases of tuning on and turning off the pull down circuit and the pull up circuit under a plurality of process, voltage and temperature (PVT) conditions.