LNBEH21PD

LNBEH21 LNB SUPPLY AND CONTROL IC WITH STEP-UP CONVERTER AND I2C INTERFACE s s s s s s s s s s s COMPLETE INTERFACE BETWEEN LNB AND I2CTM BUS BUILT-IN DC/DC CONTROLLER FOR SINGLE 12V SUPPLY OPERATION AND HIGH EFFICIENCY (Typ. 94% @ 750mA) TWO SELECTABLE OUTPUT CURRENT LIMIT (450mA / 750mA) 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 2.0 13/18V CONTROL WORD COMMUNICATION SEMI-LOWDROP POST REGULATOR AND HIGH EFFICIENCY STEP-UP PWM FOR LOW POWER LOSS: Typ. 0.56W @ 125mA 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) CABLE LENGTH DIGITAL COMPENSATION OVERLOAD AND OVER-TEMPERATURE INTERNAL PROTECTIONS I2C WITH DIAGNOSTIC BITs PowerSO-20 s s LNB SHORT CIRCUIT SOA PROTECTION WITH I2C DIAGNOSTIC BIT +/- 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 Mode and DiSEqCTM communication. In this application field, it offers a complete solution with extremely low component count, low power dissipation together with simple design and I2CTM standard interfacing. BLOCK DIAGRAM Gate Sense Step-up PWM Controller LNBEH21 Vup-Feedback VoTX Vup VoRX Vcc Byp Preregul.+ U.V.lockout +P.ON res. Linear Post-reg +Modulator +Protections ISEL EXTM SDA SCL ADDR V Select I²C interf. Enable 22KHz Diagnostics Oscill. OM=low Tone Detector DETIN DSQOUT Tone control Echo-pulses control T RISE= T FALL = 500µs TEN/VSEL 13/18V control OM=High July 2004 Rev. 1 1/22 LNBEH21 Table 1: Ordering Codes TYPE LNBEH21 PowerSO-20 (Tube) LNBEH21PD PowerSO-20 (Tape & Reel) LNBEH21PD-TR Table 2: Absolute Maximum Ratings Symbol VCC VUP IO VOTX/RX VI VDETIN VOH IGATE VSENSE Tstg Top DC Input Voltage DC Input Voltage Output Current DC Output Pins Voltage Logic Input Voltage (SDA, SCL, DSQIN, ISEL) Detector Input Signal Amplitude Logic High Output Voltage (DSQOUT) Gate Current Current Sense Voltage Storage Temperature Range Operating Junction Temperature Range Parameter Value -0.3 to 16 -03 to 25 Internally Limited -0.3 to 25 -0.3 to 7 -0.3 to 2 -0.3 to 7 ± 400 -0.3 to 1 -0.3 to 7 -40 to +150 -40 to +125 Unit V V mA V V VPP V mA V V °C °C VADDRESS Address Pin Voltage Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. Table 3: Thermal Data Symbol Rthj-case Parameter Thermal Resistance Junction-case Value 2 Unit °C/W Figure 1: Pin Configuration (top view) 2/22 LNBEH21 Table 4: Pin Description PIN N° 18 17 16 19 SYMBOL VCC GATE SENSE VUP NAME Supply Input External Switch Gate Current Sense Input Step-up Voltage FUNCTION 8V to 15V IC supply. A 220µF bypass capacitor to GND with a 470nF (ceramic) in parallel is recommended External MOS switch Gate connection of the step-up converter DC/DC Current Sense comparator input. Connected to current sensing resistor Input of the linear post-regulator. The voltage on this pin is monitored by internal step-ut controller to keep a minimum dropout across the linear pass transistor. RX Output to the LNB in DiSEqC 2.0 application. See truth tables for voltage selections and Communication Mode section for details. Bidirectional data from/to I2C bus. Clock from I2C bus. Depending on the value set for OM bit this pin enable/disable the internal 22KHz tone generator (OM=0) or switch the output voltage from 13V to 18V and vice versa (OM=1) 22kHz Tone Detector Input. Must be AC coupled to the DiSEqC 2.0 bus. Open drain output of the tone Detector to the main µcontroller for DiSEqC 2.0 data decoding. It is set LOW when a 22 KHz tone is detected. External Modulation Input acts on VOTX. Needs DC decoupling to the AC source. If not used, can be left open. Pins connected to Ground. Also internally connected to the die frame (exposed pad) for heat dissipation. Needed for internal preregulator filtering Set high or floating for IO ≤ 750mA, connect to ground for IO ≤ 450mA. Output of the linear post-regulator/modulator to the LNB. See truth tables for voltage selections. Four I2C bus addresses available by setting the Address Pin level voltage. See address pin characteristics table. 2 12 13 14 VORX SDA SCL Output Port during 22KHz Tone RX Serial Data Serial Clock TEN/VSEL DiSEqC or 13/18V TTL Logic Input DETIN DSQOUT Tone Detector Input DiSEqC Output 9 15 5 1, 6, 10, 11, 20 8 3 4 7 EXTM GND BYP ISEL VOTX ADDR External Modulator GROUND Bypass Capacitor Current Limit Select Output Port during 22KHz Tone TX Address Setting 3/22 LNBEH21 TYPICAL APPLICATION CIRCUITS Figure 2: Application Circuit for DiSEqC 1.x and Output Current < 450 mA Axial Ferrite Bead Filter F1 suggested part number: MURATA BL01RN1-A62 Panasonic EXCELS A35 D2 1N4001 IC1 F1 19 VUP ISEL 3 C2 220µF IC2 C9 100µF STS4DNFS30L C3 (***) 470nF Ceramic VoRX 2 Set TTX=1 C10(***) 10nF to LNB 17 GATE VoTX 4 LNBEH21 L1=22µH Rsc 0.1 Ω C4 (***) 470nF Ceramic 18 VCC 16 SENSE D4(***) BAT43 (**) DETIN 9 Byp 8 C5(***) 470nF Vin 12V C1 220µF 12 SDA 13 SCL EXTM 5 ADDRESS 7 0