A four-channel integrated patch-clamp amplifier with current-clamp capability

We present the first fully-integrated microchip implementation of a patch-clamp measurement system featuring both current clamp and voltage clamp modes with gain control, leak correction, series access resistance compensation, parasitic capacitive compensation capability, and input and output filters. The system was implemented in a 1-poly, 3-metal, 0.5 μm Siliconon-Sapphire process. In voltage clamp mode input-referred rms noise was measured at 3.3 pA in a 5 kHz bandwidth and in current clamp mode input-referred rms noise was measured at 150 μV in the same bandwidth. The system can compensate for the capacitance and resistance of the electrode, up to 10 pF and up to 80% of the series access resistance of 100 MΩ respectively, or 100% with phase-lag compensation. Four fully integrated dual clamp channels are contained on one 4 mm by 8 mm die. The power consumption is 30.1 mW per channel at 3.3 V.