LNBP21
LNBP SUPPLY AND CONTROL IC WITH
STEP-UP CONVERTER AND I
2
C INTERFACE
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COMPLETE INTERFACE BETWEEN LNB
AND I2CTM BUS
BUILT-IN DC/DC CONTROLLER FOR
SINGLE 12V SUPPLY OPERATION
ACCURATE BUILT-IN 22KHz TONE
OSCILLATOR
SUITS WIDELY ACCEPTED STANDARDS
FAST OSCILLATOR START-UP FACILITATES
DiSEqCTM ENCODING
BUILT-IN 22KHz TONE DETECTOR
SUPPORTS BI-DIRECTIONAL DiSEqCTM
LOOP-THROUGH FUNCTION FOR SLAVE
OPERATION
LNB SHORT CIRCUIT PROTECTION AND
DIAGNOSTIC
CABLE LENGTH DIGITAL COMPENSATION
INTERNAL OVER TEMPERATURE
PROTECTION
ESD RATING 4KV ON POWER
INPUT-OUTPUT PINS
PowerSO-20
SO-20
DESCRIPTION
Intended for analog and digital satellite STB
receivers/SatTV, sets/PC cards, the LNBP21 is a
monolithic voltage regulator and interface IC,
assembled in SO-20 and PowerSO-20,
specifically designed to provide the power and the
13/18V, 22KHz tone signalling to the LNB
SCHEMATIC DIAGRAM
Gate
Sense
Step-up
Controller
LNBP21
LT1
Feedback
LT2
Vup
Vcc
Byp
OUT
Preregul.+
U.V.lockout
+P.ON res.
Enable
I Select
V Select
Linear Post-reg
+Modulator
+Protections
EXTM
SDA
SCL
ADDR
DSQIN
I虜C
interf.
22KHz
Oscill.
Diagnostics
DETIN
Tone
Detector
DSQOUT
October 2002
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