STEVAL-LNBH05 STMicroelectronics

S T E VA L - L N B H 0 5 Power supply evaluation board for LNB based on the LNBH26S Data brief Description This evaluation board implements a DC-DC converter based on the LNBH26S device. It is used to power LNBs inside dish antennas to receive satellite TV signals. The LNBH26S is an integrated solution for supplying and interfacing satellite LNB modules in accordance with international standards. This simple and complete solution for dual tuner satellite receivers offers high performance at low cost and low external component count. The LNBH26S evaluation board includes an IC bus interface and the internal 22 kHz tone generator which is factory trimmed and can be controlled by the DSQIN pin (TTL compatible), Features allowing immediate DiSEqC data encoding. Complete interface between LNB and IC Thanks to a fully integrated step-up DC-DC bus converter, it functions with a single input voltage Built-in DC-DC converter for single 12 V supply source ranging from 8 V to 16 V. supply operation and high efficiency (typ. 93% 0.5 A) Selectable output current limit by external resistor Compliant with the output voltage specifications of principal satellite receivers (15 programmable levels) Accurate built-in 22 kHz tone generator suits widely accepted standards 22 kHz tone waveform integrity guaranteed also at no load condition Low drop post regulator and high efficiency step-up PWM with integrated power N-MOS allowing low power losses LPM function (low power mode) to reduce dissipation Overload and overtemperature internal protection with IC diagnostic bits LNB short-circuit dynamic protection 4 kV ESD tolerant on output power pins RoHS compliant September 2016 DocID029721 Rev 1 1/4 www.st.com For further information contact your local STMicroelectronics sales office Schematic diagram STEVAL-LNBH05 1 Schematic diagram Figure 1: STEVAL-LNBH05 circuit schematic D2-A LNBOUT-A V A 21 OUT- VUP-A 20 D1-A - C2 A - LNBH26S D3-A TVS-A C3 A - C5 A - 3 LX A R1 (RSEL) - L1 A 9 ISEL DiSEqC 16 Byp DSQIN-A 22 22 KHz TTL C7 Tone enable control Vin 17 Vcc or DSQIN-B 24 12 V DiSEqC ADDR 6 C4 Envelope TTL C1 FLT 2 - L1 B 8 SDA 2 I C Bus 7 SCL - 5 LX B D1-B 11 V UP-B V OUT -B 12 P-GND A -GND LNBOUT-B 4 15 C3-B C2-B C5-B D3-B TVS-B D2-B GSPG0809161555SG 2/4 DocID029721 Rev 1