OA1ZHA datasheet(25/35 Pages) STMICROELECTRONICS

Il numero della parte	OA1ZHA

Spiegazioni elettronici	Fitness and healthcare

PDF	35 Pages

Scroll/Zoom	100%

Produttore elettronici	STMICROELECTRONICS [STMicroelectronics]

Homepage	http://www.st.com

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25 / 35 page

OA1ZHA, OA2ZHA, OA4ZHA

Application information

DocID025994 Rev 2

25/35

Vout can be expressed as follows:

Equation 4

Assuming that Rf2 = Rf1 = Rf and Rg2 = Rg1 = Rg, Equation 4 can be simplified as follows:

Equation 5

The main advantage of using the chopper of the OA1ZHA, OA2ZHA and OA4ZHA, for a

low-side current sensing, is that the errors due to Vio and Iio are extremely low and may be

neglected.

Therefore, for the same accuracy, the shunt resistor can be chosen with a lower value,

resulting in lower power dissipation, lower drop in the ground path, and lower cost.

Particular attention must be paid on the matching and precision of Rg1, Rg2, Rf1, and Rf2, to

maximize the accuracy of the measurement.

ou t

shun t

I 1

–

io 1

–

out

shunt

io 1

–

OA1ZHA Scheda tecnica(PDF) 25 Page - STMicroelectronics