Electro-Magnetic Compatibiltiy (EMC)

Systems utilizing the LM9073 will not experience loss of sup-

ply or false reset signals from the regulator when subjected

to high frequency interference from a standard Bulk Current

Injection test (ISO11452 Part 4 test method). The following

test conditions and configuration (Figure 9) can be used to

verify this performance:

•

Frequency Range

1MHz to 400MHz

•

Modulation 1

(no modulation)

•

Modulation 2

1kHz sine wave, 80% AM

•

Dwell Time

1 second

•

Frequency Steps

1MHz (from 1MHz to 10MHz)

•

2MHz (from 10MHz to 200MHz)

•

20MHz (from 200MHz to 400MHz)

•

Test Method

Closed loop current probe

In this test configuration the current injected in to either the

input pin or the tracking output pin is increased until a reset

output is generated. These two pins are the most critical as

they typically will connect to a module through long lengths

of wire most likely to pick up high frequency energy. Figure

10 illustrates examples of test results on the LM9073 with

both types of modulation.

These results are just examples as actual results in any

given application will depend on numerous external factors

such as component selection, pc board layout, etc. The cur-

rent power of the injected signal is expressed indB relative to

1mA (i.e. 40dBmA = 100mA)

Figure 9. EMC Test Circuit

DS101296-24

Figure 10. Examples of BCI Test

BCI Susceptibility, Modulation 1 (CW)

DS101296-25

BCI Susceptibility, Modulation 2 (CW)

(1kHz, 80% AM Modulation)

DS101296-26

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