LNBP8L Datasheet, PDF (1/21 Pages) STMicroelectronics – 500 mA guaranteed output current

LNBP8L - LNBP9L
LNBP10L - LNBP11L
LNB supply and control voltage regulator
Preliminary data
Features
■ Simplest integrated solution for LNB remote
supply and control
■ 500 mA guaranteed output current
■ Dual input supply for reducing power
dissipation (DFN package)
■ 3-state function to enable/disable and select
the output voltage level through a single pin
■ Fast oscillator startup for DiSEq™ encoding
(LNBP9L/11L versions)
■ External 22 kHz modulation input pin
(LNBP8L/10L versions)
■ Cable length compensation, LLC pin
(LNBP10L, LNBP11L versions)
■ Short-circuit and over-temperature protection
■ LNB overload and short-circuit dynamic
protection (LNBP10L, LNBP11L versions)
■ Available in DFN8 (5 x 6 mm) and IPPAK
packages
Description
Intended for analog and digital satellite receivers,
the LNBP is a monolithic linear voltage regulator,
assembled in the DFN8 5x6 and IPPAK packages,
specifically designed to provide the powering
voltages and the interfacing signals to the LNB
down-converter. The regulator output can be logic
controlled for 13 V or 18 V (typ.) by means of the
EN/VSEL 3-state pin for remotely controlling the
LNB. When the IC is powered and put in standby
(EN/VSEL pin at high impedance), the regulator
output is disabled. In order to reduce power
dissipation, the LNBP10L/11L versions (on DFN
package) feature 2 supply inputs: V_CC1 and V_CC2.
These pins must be powered, respectively, at 15
V (min.) and 22 V (min.), and an internal switch
will automatically select the appropriate supply
voltage according to the selected output voltage.
The LNBP8L/9L versions (in the IPPAK package)
have only one supply input pin, which must be
IPPAK
DFN8 (5 x 6 mm)
supplied at 22 V (min.). Additionally, the
LNBP10L/11L versions have the LLC pin to
increment the selected output voltage value by 1
V (typ.) to compensate for the excess voltage
drop along the coaxial cable (LLC pin HIGH).
An analog 22 kHz modulation input pin (EXTM) is
available in the LNBP8L and LNBP10L versions.
An appropriate DC blocking capacitor must be
used to couple the modulating signal source to
the EXTM pin. The LNBP10L/11L versions are
also equipped with over-current dynamic
protection: as soon as an overload is detected the
output is shut down for the time T_OFF, which is
determined by the capacitor connected between
the CEXT pin and GND. After the time has
elapsed, the output is resumed for a time T_ON =
(1/12)*T_OFF (typ.). If the overload is still present,
the protection circuit will cycle again through T_OFF
and T_ON until the overload is removed. A typical
T_ON+T_OFF value is 1100 ms when a 4.7 µF
external capacitor is used on the C_EXT. This
dynamic operation can greatly reduce the power
dissipation in short-circuit condition, while
ensuring excellent power-on startup even with
highly capacitive loads on the LNB outputs.
The device is packaged in the IPPAK for through-
hole mounting and in the DFN8 5x6 for surface
mounting. Both package solutions are offered in
two versions: with ten pins (LNBP9L/11L) to use
with the integrated 22 kHz tone generator, or with
the EXTM pin (LNBP8L/10L) to use external 22
kHz sources. All versions have built-in thermal
protection to prevent overheating damage.
November 2008
Rev 1
This is preliminary information on a new product in development or undergoing evaluation. Details are subject to change
without notice.
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