Patent ID: 8861125

Claim:
A preamplifier system comprising: a reference stage configured to set a magnitude of a clamping voltage for a reference node based on a reference current generated in an adjustable reference current path; and an output stage comprising an adjustable slew current source that is configured to provide an activation current to the reference node in response to at least one activation signal, the output stage to generate an output current at an output of the output stage with a magnitude that is based on the clamping voltage, wherein the adjustable slew current source comprises: a first adjustable slew current source that is activated in response to a first activation signal to provide the activation current to the reference node to increase the output current and a second adjustable slew current source that is activated in response to a second activation signal to provide a deactivation current from the reference node to decrease the output current, wherein the reference stage is further configured to set a magnitude of a first clamping voltage and a second clamping voltage for the reference node based on the reference current, the reference stage comprises: a first clamping transistor coupled to the reference node, the first clamping transistor being activated to conduct the activation current based on a reference voltage at the reference node increasing to a magnitude that is approximately equal to the first clamping voltage in response to activation of the first adjustable slew current source; and a second clamping transistor coupled to the reference node, the second clamping transistor being activated to conduct the deactivation current based on the reference voltage decreasing to a magnitude that is approximately equal to the second clamping voltage in response to activation of the second adjustable slew current source.