LNBH221_06 Datasheet, PDF (1/27 Pages) STMicroelectronics – Dual LNB supply and control IC with Step-Up converter and I2C interface

LNBH221
Dual LNB supply and control IC with
Step-Up converter and I²C interface
Feature summary
I All the features are the same for both section
I Complete and independent interface between
LNBS and relevant I²C^TM BUS
I BUILT-IN DC/DC controller for single 12V
supply operation and high efficiency (Typ. 93%
@ 500mA)
I LNB output current guaranteed up to 500mA
I Both compliant with eutelsat and directv output
voltage specification accurate BUILT-IN
22KHz tone oscillator suits widely accepted
standards
I Fast oscillator start-up facilitates DiSEqC^TM
encoding
I BUILT-IN 22KHz tone detector supports bi-
directional DiSEqC^TM 2.0
I Semi-lowdrop post regulator and high
efficiency step-up pwm for low power loss: Typ.
0.56W @ 125mA
I Two output pins suitable to bypass the output r-
l filter and avoid any tone distorsion (R-L filter
as per DiSEqC 2.0 SPECs, see application
circuit on pag. 7, 8)
I Overload and over-temperature internal
protections
I Overload and over-temperature I²C diagnostic
BITs
I LNB short circuit soa protection with I²C
diagnostic bit
I +/- 4KV ESD tolerant on input/output power
pins
Description
Intended for analog and digital DUAL Satellite
STB receivers/SatTV, sets/PC cards, the
LNBH221 is a voltage regulator and interface IC,
POWER SO-36
assembled in POWER SO-36, specifically
designed to provide the power 13/18V, and the
22KHz tone signalling for two independent LNB
down converters or to a multiswitch box that could
be independently powered and set. In this
application field, it offers a complete solution with
extremely low component count, low power
dissipation together with simple design and I²C^TM
standard interfacing.
February 2006
Rev. 5
1/27
www.st.com
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