TISP4072F3, TISP4082F3

SYMMETRICAL TRANSIENT

VOLTAGE SUPPRESSORS

8

MARCH 1994 - REVISED SEPTEMBER 1997

PRODUCT

INFORMATION

protection voltage

This increase is dependent on the rate of current rise, di/dt, when the TISP is clamping the voltage in its

can be made from the surge generator voltage rate of rise, dv/dt, and the circuit resistance.

As an example, the CCITT IX K17 1.5 kV, 10/700 µs surge has an average dv/dt of 150 V/µs, but, as the rise

is exponential, the initial dv/dt is higher, being in the region of 450 V/µs. The instantaneous generator output

resistance is 25

becomes 45

measured

di/

dt and protection voltage increase will be lower due to inductive effects and the finite slope

resistance of the TISP breakdown region.

capacitance

off-state capacitance

an ac voltage of 100 mV. The typical 25°C variation of capacitance value with ac bias is shown in Figure 13

constant over the range of normal telecommunication frequencies.

Figure 13.

APPLICATIONS INFORMATION

NORMALISED CAPACITANCE

V

1

10

100

1000

0.70

0.75

0.80

0.85

0.90

0.95

1.00

1.05

AIXXAA

Normalised to V

DC Bias, V

RMS AC TEST VOLTAGE

vs