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

AMR limitation

DS13237 - Rev 6

page 25/38