Patent ID: 7251178

Claim:
A current sense amplifier, comprising: a voltage comparator having a first input, a second input and an output; a first clamping device coupled between the first input of the voltage comparator and a first input signal node, the first clamping device being coupled to a reference voltage; a second clamping device coupled between the second input of the voltage comparator and a second input signal node, the second clamping device being coupled to the reference voltage; a current mirror having a first side and a second side, the current mirror first side including a first transistor coupled between a voltage source and the first clamping device and the current mirror second side including a second transistor coupled between the voltage source and the second clamping device, the first and second transistors including sources, gates and drains, wherein the gates of the first and second transistors are coupled together, and the gate and drain of the first transistor are coupled together; and a sensing scheme including an actively balanced capacitance coupled to the source and drain of the second transistor, wherein the actively balanced capacitance includes a third transistor with a source, gate and drain, the source and gate of the third transistor being coupled to the source and drain of the second transistor, and the drain of the third transistor being coupled to a drain node to actively balance capacitive loads of the current mirror.