Patent ID: 11968468
Assignee: OMNIVISION TECHNOLOGIES, INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 18:
19. The ramp buffer circuit of claim 15, wherein the analog to digital converter further comprises:
a first switch coupled between the variable current source circuit and the input of the current comparator circuit, wherein the variable current source circuit and the first switch are coupled between the power line and the input of the current comparator circuit; and
a second switch coupled between the variable current source circuit and the assist bias voltage generator,
wherein the first switch is configured to be on and the second switch is configured to be off during a calibration operation, wherein the first variable current is configured to be provided from the variable current source circuit to the input of the current comparator circuit through the first switch during the calibration operation,
wherein the first switch is configured to be off and the second switch is configured to be on after the calibration operation is complete, wherein a second variable current is configured to be provided from the variable current source circuit to the assist bias voltage generator through the second switch after the calibration operation is complete.