AN4071 datasheet(8/27 Pages) STMICROELECTRONICS

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Datasheet parameters

AN4071

8/27

Doc ID 022939 Rev 1

Datasheet parameters

3.1

Input common mode voltage range - VICM

The VICM is defined as the voltage range where both inputs must remain to guarantee the

functionality of the device. When the input common mode range covers both power supply

rails 0 V and VCC, it is a rail-to-rail input stage.

Regarding the use of a rail-to-rail (R2R) comparator, from a technical point of view, if the

R2R input capability is not needed, it is always better to choose a comparator without R2R

input stage. The power consumption is, in that case, obviously smaller and the device cost is

lower.

3.2

Input offset voltage - VIO (VTRIP)

The input offset voltage (VIO) can be defined as the differential input voltage to apply in

order to be at the toggling level. Input offset voltage limits the resolution of comparators.

Therefore, for very small signals (in the same order as the VIO), the comparator toggles at

an undesired value or does not toggle at all.

Figure 7.

Voltage marking

Figure 8.

Input-trip point VTRIP

Figure 9.

Input offset voltage VIO

AN4071 Datasheet(PDF) 8 Page - STMicroelectronics