ADuM1234

Rev. 0 | Page 8 of 12

APPLICATION NOTES

COMMON-MODE TRANSIENT IMMUNITY

In general, common-mode transients consist of linear and

sinusoidal components. The linear component of a common-

mode transient is given by

where ΔV/Δt is the slope of the transient shown in Figure 11

and Figure 12.

The transient of the linear component is given by

Figure 8 characterizes the ability of the ADuM1234 to operate

correctly in the presence of linear transients. The data is based

on design simulation and is the maximum linear transient

magnitude that the ADuM1234 can tolerate without an

operational error. This data shows a higher level of robustness

than what is listed in Table 5 because the transient immunity

values obtained in Table 5 use measured data and apply

allowances for measurement error and margin.

TEMPERATURE (°C)

100

–40

0

40

80

–20

20

60

400

300

200

350

250

150

100

50

0

WORST-CASE PROCESS VARIATION

BEST-CASE PROCESS VARIATION

Figure 8. Transient Immunity (Linear Transients) vs. Temperature

The sinusoidal component (at a given frequency) is given by

where:

f is the frequency of the sinusoidal.

The transient magnitude of the sinusoidal component is given by

Figure 9 and Figure 10 characterize the ability of the

ADuM1234 to operate correctly in the presence of sinusoidal

transients. The data is based on design simulation and is the

ADuM1234 can tolerate without an operational error. Values

for immunity against sinusoidal transients are not included in

Table 5 because measurements to obtain such values have not

been possible.

FREQUENCY (MHz)

2000

0

500

1000

1500

1750

250

750

1250

300

200

100

250

150

0

50

WORST-CASE PROCESS VARIATION

BEST-CASE PROCESS VARIATION

Figure 9. Transient Immunity (Sinusoidal Transients),

27°C Ambient Temperature

FREQUENCY (MHz)

2000

0

500

1000

1500

1750

250

750

1250

250

100

150

200

50

0

WORST-CASE PROCESS VARIATION

BEST-CASE PROCESS VARIATION

Figure 10. Transient Immunity (Sinusoidal Transients),

100°C Ambient Temperature

ΔV

Δt

ΔV

Δt

5V

15V

15V

5V

15V

15V

Figure 11. Common-Mode Transient Immunity Waveforms, Input to Output

ΔV

Δt

ΔV

Δt

15V

15V

15V

15V

15V

15V

Figure 12. Common-Mode Transient Immunity Waveforms,

Between Outputs