Richard K Epps

US Patent:

20060176030, Aug 10, 2006

Filed:

Feb 4, 2005

Appl. No.:

11/051425

Inventors:

Richard Van Epps - Vancouver WA, US
Ira Pollock - Hillsboro OR, US
Michael Stevens - Hillsboro OR, US
Dale Daniels - Tigard OR, US

International Classification:

G05F 1/10
H02J 3/12

US Classification:

323234000

Abstract:

A differential termination and attenuator network having an internal common mode termination voltage generator includes first and second termination resistors coupled in parallel with corresponding resistive attenuator circuits. A monitoring circuit coupled to input nodes of the network generates an output signal representative of the combination of a DC common mode voltage on the input nodes and an internal termination voltage. A control circuit generates scaled termination and compensation voltages and associated drive currents using the internal termination voltage and the monitoring circuit output signal. The scaled termination voltage and the scaled compensation voltage operate on the differential termination and attenuation network to optimize the dynamic range of a differential amplifier connected to the first and second attenuator outputs and null the DC currents at the input of the network. The internal termination voltage generator receives termination voltage parameters from a measurement instrument for generating the internal termination voltage.

US Patent:

20060176074, Aug 10, 2006

Filed:

Feb 4, 2005

Appl. No.:

11/051653

Inventors:

Richard Van Epps - Vancouver WA, US
Ira Pollock - Hillsboro OR, US

International Classification:

H03K 17/16

US Classification:

326030000

Abstract:

A differential termination and attenuator network having an automated common mode termination voltage generator includes first and second termination resistors coupled in parallel with corresponding resistive attenuator circuits. A monitoring circuit coupled to input nodes of the network generates an output signal representative of the combination of a DC common mode voltage on the input nodes and an adjustable termination voltage. A control circuit generates scaled termination and compensation voltages and associated drive currents using the adjustable termination voltage and the monitoring circuit output signal. The scaled termination voltage and the scaled compensation voltage operate on the differential termination and attenuation network to optimize the dynamic range of a differential amplifier connected to the first and second attenuator outputs. An automated termination voltage generator automatically adjusts the adjustable termination voltage to match the DC common mode input voltage, which nulls the DC currents at the input nodes.

US Patent:

20060178846, Aug 10, 2006

Filed:

Feb 4, 2005

Appl. No.:

11/051596

Inventors:

Ira Pollock - Hillsboro OR, US
Richard Van Epps - Vancouver WA, US

International Classification:

G06F 19/00

US Classification:

702057000

Abstract:

A differential termination and attenuator network receives a differential input signal having a DC common mode voltage. The network circuit includes first and second input termination resistors coupled in parallel with corresponding resistive attenuator circuits. A monitoring circuit coupled to input nodes of the network generates an output signal representative of the combination of a DC common mode voltage on the input nodes and an applied termination voltage. A control circuit receives the output signal from the monitoring circuit and the applied termination voltage and generates a scaled termination voltage and a scaled compensation voltage and drive currents. The scaled termination and compensation voltages and drive currents provide DC currents through the input termination resistances and the attenuators for nulling DC currents at the network input nodes and provides a DC common mode voltage output from the first and second attenuators for optimizing the dynamic range of a differential measurement amplifier.

US Patent:

20070143638, Jun 21, 2007

Filed:

Dec 20, 2005

Appl. No.:

11/314357

Inventors:

Kenneth Dobyns - Beaverton OR, US
Michael Mende - Portland OR, US
Richard Van Epps - Vancouver WA, US
Michael Stevens - Hillsboro OR, US

International Classification:

G06F 1/00

US Classification:

713300000, 700297000, 710260000, 710100000, 327536000

Abstract:

An accessory device voltage management system includes an accessory device selectively coupled to a host. The host provides a bulk power supply and a low power supply voltage to the accessory device. The host receives accessory device parameters from the device and determines if the accessory device is a valid and supported device and, if so, sends commands to the accessory device to couple the bulk power supply voltage to a power supply circuit in the accessory device. The power supply circuit in the accessory device generates at least a first regulated voltage output.