LNBH26PQR STMicroelectronics

LNBH26 Dual LNBS supply and control IC with step-up and IC interface Features Complete interface between LNB and IC bus Built-in DC-DC converter for single 12 V supply operation and high efficiency (typ. 93% 0.5 A) Selectable output current limit by external resistor Compliant with main satellite receivers output voltage specification (15 programmable levels) QFN24 (4 x 4 mm) Accurate built-in 22 kHz tone generator suits widely accepted standards 22 kHz tone waveform integrity guaranteed Description also at no load condition Intended for analog and digital dual satellite Low drop post regulator and high efficiency receivers/Sat-TV, and Sat-PC cards, the LNBH26 step-up PWM with integrated power N-MOS is a monolithic voltage regulator and interface IC, allowing low power losses assembled in QFN24 4x4 specifically designed to LPM function (low power mode) to reduce provide the 13/18 V power supply and the 22 kHz dissipation tone signalling to the LNB down-converter in the Overload and overtemperature internal antenna dishes or to the multi-switch box. In this protection with IC diagnostic bits application field, it offers a complete solution for dual tuner satellite receivers with extremely low LNB short-circuit dynamic protection component count, low power dissipation together +/- 4 kV ESD tolerant on output power pins with simple design and IC standard interfacing. Applications STB satellite receivers TV satellite receivers PC card satellite receivers Table 1. Device summary Order code Package Packaging LNBH26PQR QFN24 (4 x 4) Tape and reel February 2012 Doc ID 022771 Rev 1 1/38 www.st.com 38Contents LNBH26 Contents 1 Block diagram 3 2 Application information (valid for each section A/B) . 4 2.1 DISEQC data encoding (DSQIN pin) . 4 2.2 Data encoding by external 22 kHz tone TTL signal 4 2.3 Data encoding by external DiSEqC envelope control through the DSQIN pin 5 2.4 LPM (low power mode) . 5 2.5 DISEQC 2.0 implementation 5 2.6 Output current limit selection . 6 2.7 Output voltage selection . 6 2.8 Diagnostic and protection functions 6 2.9 Surge protections and TVS diodes . 7 2.10 FLT: Fault FLAG . 7 2.11 VMON: output voltage diagnostic 7 2.12 TMON: 22 kHz tone diagnostic . 8 2.13 TDET: 22 kHz tone detection . 8 2.14 IMON: minimum output current diagnostic . 8 2.15 PDO: overcurrent detection on output pull-down stage . 8 2.16 Power-on IC interface reset and undervoltage lockout . 8 2.17 PNG: input voltage minimum detection . 9 2.18 ISW: inductor switching current limit . 9 2.19 COMP: boost capacitor ESR . 9 2.20 OLF: overcurrent and short-circuit protection and diagnostic . 9 2.21 OTF: thermal protection and diagnostic 10 3 Pin configuration . 11 4 Maximum ratings . 15 5 Typical application circuits 16 6 IC bus interface . 18 2/38 Doc ID 022771 Rev 1