For further information, including the LT4356 Datasheet and information
on how to obtain Demo Board Samples, please complete the reply slip or visit
http://www.arrowne.com/innov/in216/f_1431.shtml
22
POWER AND LINEAR IC
SOLUTIONS
Even short duration, high voltage power spikes threaten
the electronics in automotive and industrial applications
although they may only last from a few µs to hundreds
of ms. Critical electronic subsystems must survive these
transients, rejecting surges, spikes and transients; in many
applications, they must also operate reliably throughout
such events.
Linear Technology has developed a new means of blocking
surges, spikes and transients commonly found in automotive
and industrial systems. The LT4356 eliminates the need for bulky
filtering components while isolating low-voltage circuitry from
damage. The regulating action eliminates the need for high-
voltage rated components downstream of the LT4356, allowing
use of inexpensive low-voltage components.
The LT4356 surge stopper implements a series-pass regulator with
an external N-channel MOSFET, as can be seen in the diagram of
a typical application circuit. Under normal conditions, the LT4356
drives the MOSFET fully on so that input power passes directly
through to the load circuitry with little loss. If the input voltage rises
beyond a set threshold, the LT4356 begins regulating the output
at a safe level.
After the surge has dissipated, the LT4356 returns to normal
operation or disconnects the output if the fault persists.
In addition to voltage regulation, the LT4356 offers overcurrent
and reverse input protection and a ‘micropower’ shutdown state
that reduces supply current to about 7µA. The LT4356 limits inrush
current at turn-on by soft-starting the MOSFET.
The LT4356 tolerates reverse voltage down to -60V on its input and
can drive a second reverse-blocking MOSFET to stop the reverse
voltage passing through to the load. The LT4356’s wide operating
voltage range, from 4V minimum to 100V absolute maximum,
enables it to operate in systems where the input voltage may sag
on the low side as well as surge on the high side of nominal.
The LT4356 surge stopper offers solid front-end protection for
electronic control systems. Compared to blocking diodes and filter
inductors, it absorbs less board space and reduces heat dissipation
and voltage loss. Its higher efficiency and wider usable voltage
range allow designers to incorporate more functionality into space-
constrained products.
Features
U
Front-end protection
U
Compact, low heat dissipation
U
High efficiency
U
Wide operating voltage: 4V to 100V
U
Tolerates <-60V reverse input voltage
Applications
U
Protection from transients, surges, spikes
U
Overcurrent protection, reverse input protection
Protects sensitive electronics from high voltage transients
New Device Stops High Voltage Surges
ENQUIRY 1431
Linear Technology LT4356 Datasheet available
and FREE Demo Board Sample to qualifying
customers! Please complete the reply slip or
visit the weblink below.
Franchised with
Arrow in Denmark,
Norway, Sweden,
UK and Ireland
