Axon Axopatch 200B - Chapter 8 Reference Section: Principles of Operation; Headstages; Principals of Operation; Resistor Feedback

PRINCIPLES OF OPERATION
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Chapter 8
Chapter 8
Reference Section: Principles of Operation
Headstages
Principals of Operation
Patch-clamp headstages are current-to-voltage (I-V) converters. That is, the voltage output
is proportional to the current input. In contrast, conventional microelectrode amplifier
headstages are voltage followers in which the voltage output corresponds to the voltage
input.
Resistor Feedback
The essential parts of a resistive headstage are shown in Figure 15:
+
V
p
BOOST
-
+
-
R
I
f
OFFSET
AND
SCALING
HIGH-
FREQUENCY
BOOST
I
V
o
CIRCUIT
f
PROBE
Figure 15.
Resistive headstage.