Embodiments of the current-mode track and hold circuit comprise a cascode
input stage, a dynamic biasing stage, a cascode output stage, and a
switch operable to interconnect the input stage and the output stage. The
input stage is connected to receive an input current. The dynamic biasing
stage is connected to receive a scaled version of the input current as a
dynamic biasing current and dynamically biases the input stage in
response to the dynamic biasing current. Dynamically biasing the
track-and-hold circuit in response to a dynamic biasing current that is a
scaled version of the input current significantly increases the maximum
peak-to-peak voltage swing allowed at the input of the track-and-hold
circuit and enables a corresponding increase in signal-to-noise ratio.
These benefits are obtained at the expense of only a small increase in
power consumption.