LNBEH21

LNBEH21 LNB SUPPLY AND CONTROL IC WITH STEP-UP CONVERTER AND I2C INTERFACE s COMPLETE INTERFACE BETWEEN LNB AND I2CTM BUS s BUILT-IN DC/DC CONTROLLER FOR SINGLE 12V SUPPLY OPERATION AND HIGH EFFICIENCY (Typ. 94% @ 750mA) s TWO SELECTABLE OUTPUT CURRENT LIMIT (450mA / 750mA) s ACCURATE BUILT-IN 22KHz TONE PowerSO-20 OSCILLATOR SUITS WIDELY ACCEPTED STANDARDS ) s FAST OSCILLATOR START-UP FACILITATES t(s DiSEqCTM ENCODING s BUILT-IN 22KHz TONE DETECTOR uc SUPPORTS BI-DIRECTIONAL DiSEqCTM 2.0 d s 13/18V CONTROL WORD ro COMMUNICATION P s SEMI-LOWDROP POST REGULATOR AND HIGH EFFICIENCY STEP-UP PWM FOR te LOW POWER LOSS: Typ. 0.56W @ 125mA le s TWO OUTPUT PINS SUITABLE TO BYPASS o THE OUTPUT R-L FILTER AND AVOID ANY s TONE DISTORSION (R-L FILTER AS PER b DiSEqC 2.0 SPECs, SEE APPLICATION O CIRCUIT) - s CABLE LENGTH DIGITAL COMPENSATION t(s) s OVERLOAD AND OVER-TEMPERATURE INTERNAL PROTECTIONS I2C WITH c DIAGNOSTIC BITs du BLOCK DIAGRAM s LNB SHORT CIRCUIT SOA PROTECTION WITH I2C DIAGNOSTIC BIT s +/- 4KV ESD TOLERANT ON INPUT/ OUTPUT POWER PINS DESCRIPTION Intended for analog and digital satellite STB receivers/SatTV, sets/PC cards, the LNBEH21 is a monolithic voltage regulator and interface IC, assembled in POWER SO-20, specifically designed to provide the 13/18V power supply and the 22KHz tone signalling to the LNB downconverter in the antenna or to the multiswitch box. The LNBEH21 supports both methods of communication currently used, 13/18V Control Word Communication Mo...