High speed edge detection

摘要

Analog circuits for detecting edges in pixel arrays are disclosed. A comparator may be configured to receive an all pass signal and a low pass signal for a pixel intensity in an array of pixels. A latch may be configured to receive a counter signal and a latching signal from the comparator. The comparator may be configured to send the latching signal to the latch when the all pass signal is below the low pass signal minus an offset. The latch may be configured to hold a last negative edge location when the latching signal is received from the comparator.

主权项

1. A method, comprising:
detecting, by a comparator, an edge by determining when an all pass signal is below a low pass signal minus an offset or the all pass signal is above the low pass signal plus the offset; sending, by the comparator, a latching signal to a latch when the edge is detected; and holding, by the latch, a last edge location when the latching signal is received from the comparator.