HOLT INTEGRATED CIRCUITS

10

LIGHTNING PROTECTION

All SENSEn inputs are protected to RTCA/DO-160G, Section 22 Pin Injection Test, Categories A3 and B3, Waveforms 3, 4, 5A,

5B with the recommended external 3k

series resistor. Table 2 and Figure 12 give values and waveforms. See Application Note

AN-305 for recommendations on lightning protection of Holt’s family of Discrete-to-Digital devices.

Ω

Figure 16. Lightning Waveforms

Table 2. Waveform Peak Amplitudes

Level

Waveforms

3/3

4/1

5A/5A

Voc (V) / Isc (A)

Voc (V) / Isc (A)

Voc (V) / Isc (A)

3

600/24

300/60

300/300

5B/5B

Voc (V) / Isc (A)

300/300

0.0

0.3

0.5

0.8

1.0

Voltage Waveform 4

T2

T1

V(%)

T1 = 6.4µs +/-20%

T2 = 69µs +/-20%

t

50%

Peak

0.0

0.3

0.5

0.8

1.0

Current/Voltage Waveform 5A

T2

T1

I/V (%)

T1 = 40µs +/-20%

T2 = 120µs +/-20%

t

50%

Peak

-1.0

-0.5

0.0

0.5

1.0

t

Voltage/CurrentWaveform 3

Peak

50%

V/I (%)

1us/div.

0.0

0.3

0.5

0.8

1.0

Current/Voltage Waveform 5B

T2

T1

I/V (%)

T1 = 50µs +/-20%

T2 = 500µs +/-20%

t

50%

Peak

FUNCTIONAL DESCRIPTION (cont.)

HI-8428-R