6.13

AMR limitation

In case of important differential input voltage, a high current above the maximum Iin = 5 mA specified in the AMR

table may appear on the input pins.

As shown in Figure 48, for example, when using the TSC212 current sensing device, a differential input voltage

generates a current thru the input pins defined by:

Iin= Vdiff

Rin//R1+R2

(12)

If Vdiff = 26 V, the current Iin can rise, up to 23.4 mA

Iin= 26V1.1kΩ=23.4mA

(13)

Figure 48. TSC212 with input differential voltage

VCC

OUT

VREF

Vin+

R3

R1

+

-

R4

R2

TSC212

1kΩ

1kΩ

1MΩ

1MΩ

Iin

Vdiff

Rin

2.5kΩ

Therefore, to avoid silicon damage, the input current must be limited to 5 mA.

The differential input voltages should be limited to:

•

Vdiff = +/- 10 V for the TSC210

•

Vdiff = +/- 7.7 V for the TSC211

•

Vdiff = +/- 5.6 V for the TSC212

•

Vdiff = +/- 11.8 V for the TSC213

•

Vdiff = +/- 11.1 V for the TSC214

•

Vdiff = +/- 11.4 V for the TSC215

To match this requirement a serial resistance can be used, but precision would be affected, see

Section 6.12: Filtering input stage.

Alternative methods can be the use of Zener diode or even application restriction.

TSC210, TSC211, TSC212, TSC213, TSC214, TSC215

Application information

DS13237 - Rev 7

page 25/38