Data converter for CT data acquisition system

Patent · Tue Mar 21 04:00:00 EST 1989

OSTI ID:6088006

Acharya, K C; Schanen, P C

This patent describes data converter circuitry for a radiation imaging data acquisition system, comprising: a programmable gain amplifier circuit having a resistor attenuator stage and a fixed gain amplifier stage, the resistor attenuator stage providing a plurality of paths connecting the input of the programmable gain amplifier circuit with the input of the fixed gain amplifier stage, and switch means responsive to a signal received at the input of the data converter circuitry to select one of the paths for communication of the signal to the fixed gain amplifier stage, thereby selecting the gain to be provided by the programmable gain amplifier to the signal; and means for periodically setting the input of the fixed gain amplifier stage to ground, as auto-zeroing circuit for determining the differential input voltage that must be applied across the fixed gain amplifier stage to make its output voltage zero when the output of the fixed gain amplifier stage is set to ground, and means for applying the determined differential input voltage to the fixed gain amplifier stage as correction to the input offset voltage when the input of the fixed gain amplifier stage is not set to ground.

• Assignee: General Electric Co., Milwaukee, WI
• Patent Number(s): US 4815118
• OSTI ID: 6088006
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420800* -- Engineering-- Electronic Circuits & Devices-- (-1989)
99 GENERAL AND MISCELLANEOUS
990220 -- Computers
Computerized Models
& Computer Programs-- (1987-1989)
AMPLIFIERS
COMPUTERIZED TOMOGRAPHY
DATA ACQUISITION SYSTEMS
DATA PROCESSING
DESIGN
DIAGNOSTIC TECHNIQUES
ELECTRICAL EQUIPMENT
ELECTRONIC EQUIPMENT
EQUIPMENT
IMAGE PROCESSING
IMAGE SCANNERS
PROCESSING
RESISTORS
TOMOGRAPHY