Question

In the ISFET pH measurement system, the voltage circuit has ........ impedance and the current circuit has ......... impedance.

• A. High, Low
• B. zero, High
• C. Low, zero
• D. Low, High

Hint:

In ISFET systems, ensuring high impedance in the voltage circuit and low impedance in the current circuit is crucial for accurate measurements.

Answer 1

The Correct Option is A

Step 1: ISFET voltage circuit characteristics.
The voltage circuit in an ISFET measurement system must have high impedance to ensure that the small voltage signal is not disturbed.

Step 2: ISFET current circuit characteristics.
The current circuit, on the other hand, has low impedance to allow for accurate measurement of the current without interfering with the system.

Final Answer: \[ \boxed{\text{High, Low}} \]