CPC7695 Datasheet, PDF (22/25 Pages) Clare, Inc. – Line Card Access Switch

INTEGRATED CIRCUITS DIVISION
transient has not passed, current will again flow up to
the value allowed by the dynamic DC current limiting
of the switches and heating will resume, reactivating
the thermal shutdown mechanism. This cycle of
entering and exiting the thermal shutdown mode will
continue as long as the fault condition persists. If the
magnitude of the fault condition is great enough, the
external secondary protector will activate shunting the
fault current to ground.
2.11 External Protection Elements
The CPC7695 requires only over voltage secondary
protection on the loop side of the device. The
integrated protection feature described above negates
the need for additional external protection on the SLIC
side. The secondary protector must limit voltage
transients to levels that do not exceed the breakdown
voltage or input-output isolation barrier of the
CPC7695. A foldback or crowbar type protector is
recommended to minimize stresses on the CPC7695.
Consult IXYS Integrated Circuits Division’s application
note, AN-100, Designing Surge and Power Fault Protection
Circuits for Solid State Subscriber Line Interfaces for
equations related to the specifications of external
secondary protectors, fused resistors and PTCs.
CPC7695
22
www.ixysic.com
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