Application information

OA1NP, OA2NP, OA4NP

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Figure 40. Potentiostat schematic using the OA1NP (or OA2NP)

4.8

Fast desaturation

When the OA1NP, OA2NP, and OA4NP, operational amplifiers go into saturation mode, they

take a short period of time to recover, typically thirty microseconds. When recovering after

saturation, the OA1NP, OA2NP, and OA4NP series does not exhibit any voltage peaks that

could generate issues (such as false alarms) in the application (see Figure 17). This is

because the internal gain of the amplifier decreases smoothly when the output signal gets

Thus, to maintain signal integrity, the user should take care that the output signal stays at

100 mV from the supply rails.

With a trans-impedance schematic, a voltage reference can be used to keep the signal

away from the supply rails.

4.9

Using the OA1NP, OA2NP, OA4NP series in comparator mode

The OA1NP, OA2NP, and OA4NP series can be used as a comparator. In this case, the

output stage of the device always operates in saturation mode. In addition, Figure 4 shows

the current consumption is not bigger and even decreases smoothly close to the rails. The

OA1NP, OA2NP, and OA4NP are obviously operational amplifiers and are therefore

optimized to be used in linear mode. We recommend to use the TS88 series of nanopower

comparators if the primary function is to perform a signal comparison only.