Patent ID: 7532147

Claim:
An analog voltage latch comprising: a window comparator operable to compare an analog voltage latch output and an analog input voltage to produce a comparison result; an S-R latch operable to determine the relation between the analog voltage latch output and the analog input voltage according to the comparison result and to produce an S-R latch result; a latching select block operable to activate or deactivate the latching of the analog input voltage; an up/down counter operable to increase or decrease number of counts based on the S-R latch result and a clock signal and to produce a digital counter output; a digital-to-analog converter operable to convert the digital counter output to an analog voltage as the analog voltage latch output; an operational amplifier-based source follower operable to buffer the analog voltage latch output for comparison action in the window comparator; and a pair of a resistor and a current source operable to provide a voltage drop required by the window comparator.