ACS108-5Sx

4/8

®

HIGH INDUCTIVE SWITCH-OFF OPERATION

At the end of the last conduction half-cycle, the load current reaches the holding current level IH, and the

ACS™ switch turns off. Because of the inductance L of the load, the current flows through the avalanche

diode D and decreases linearly to zero. During this time, the voltage across the switch is limited to the

to 10 H); it can reach about 20 mJ and is dissipated in the clamping section that is especially designed for

that purpose.

AC LINE TRANSIENT VOLTAGE RUGGEDNESS

The ACS108 switch is able to safely withstand the AC line transient voltages either by clamping the low

energy spikes or by breaking over under high energy shocks.

The test circuit in Figure 4 is representative of the final ACS™ application and is also used to stress the

ACS™ switch according to the IEC61000-4-5 standard conditions. Thanks to the load, the ACS™ switch

withstands the voltage spikes up to 2 kV above the peak line voltage. It will break over safely even on resis-

tive load where the turn-on current rise is high as shown in Figure 4. Such non-repetitive testing can be

done 10 times on each AC line voltage polarity.

Fig. 1: Turn-off operation of the ACS108 switch

with an electro valve: waveform of the gate current

Fig. 2: ACS108 switch static characteristic.

T

ime (400µs/div)

(10 mA/div)

(200V/div)

Fig. 3: Overvoltage ruggedness test circuit for resis-

tive and inductive loads according to IEC61000-4-5

standard.

R = 150

Fig. 4: Current and voltage of the ACS™ during

IEC61000-4-5 standard test with a 150

Ω - 10µH

Iout (2 A/div)

Vout (200 V/div)

dI/dt = 100 A/µs

RL

Ω

AC LINE &

SURGE VOLTAGE

GENERATOR

G

COM

OUT

ACSxx

ON

S

D