LNBK20D2 STMicroelectronics, LNBK20D2 Datasheet - Page 2

• Manufacturer Part Number: LNBK20D2
• Description: LNB SUPPLY AND CONTROL VOLTAGE REGULATOR (PARALLEL INTERFACE)
• Manufacturer: STMicroelectronics

LNBK20D2
available (EXTM). An appropriate DC blocking
capacitor must be used to couple the modulating
signal source to the EXTM pin. When external
modulation is not used, the relevant pin can be left
open.
Two pins are dedicated to the overcurrent
protection/monitoring: CEXT and
overcurrent protection circuit works dynamically:
as soon as an overload is detected in either LNB
output, the output is shut-down for a time Toff
determined by the capacitor connected between
CEXT and GND. Simultaneously the OLF pin, that
is an open collector diagnostic output flag, from
HIGH IMPEDANCE state goes LOW.
After the time has elapsed, the output is resumed
for a time t
(*): External components are needed to comply to level 2.x and above (bidirectiona) DiSEqC
trademark or EUTELSAT.
PIN CONFIGURATION (top view)
2/14
on
=1/15t
off
(typ.) and OLF goes in HIGH
OLF. The
IMPEDANCE. If the overload is still present, the
protection circuit will cycle again through t
ton until the overload is removed. Typical t
value is 1200ms when a 4.7 F external capacitor
is used.
This dynamic operation can greatly reduce the
power dissipation in short circuit condition, still
ensuring excellent power-on start up even with
highly capacitive loads on LNB outputs.
The device is packaged in Multiwatt15 for
thru-holes mounting and in PowerSO-20 for
surface mounting. When a limited functionality in a
smaller package matches design needs, a range
of cost-effective PowerSO-10 solutions is also
offered.
protection against overheating damage.
All
™
versions
bus hardware requirements. DiSEqC
have
built-in
thermal
off
on
™
+t
and
is a
off