ACST12-7CT-TR STMICROELECTRONICS [STMicroelectronics], ACST12-7CT-TR Datasheet - Page 7

• Manufacturer Part Number: ACST12-7CT-TR
• Description: Transient protected AC power switch
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ACST12
2.2
Figure 17. Universal drum motor control – typical diagram
AC line transient voltage ruggedness
In comparison with standard TRIACs, which are not robust against surge voltage, the
ACST12 is self-protected against over-voltage, specified by the new parameter V
ACST12 switch can safely withstand AC line transient voltages either by clamping the low
energy spikes or by switching to the on state (for less than 10 ms) to dissipate higher energy
shocks through the load. This safety feature works even with high turn-on current rises.
The test circuit of
ACST switch according to the IEC 61000-4-5 standard conditions. Thanks to the load which
is limiting the current, the ACST switch withstands the voltage spikes up to 2 kV above the
peak line voltage. The protection is based on an overvoltage crowbar technology. The
ACST12 switches safely to the on state as shown in
blocking voltage capability after the surge. Such a non repetitive test can be done at least 10
times on each AC line voltage polarity.
Figure 18
AC Mains
represents the ACST12 application, and is used to stress the
Speed motor
Stator
regulation
Universal motor
ACST
Rotor
Vcc
12V
Figure
MCU
Motor direction
setting
Rg
19. The ACST12 recovers its
MCU
Application information
CL
. The
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