STEVAL-LNBH04 STMicroelectronics

S T E VA L - L N B H 0 4 Power supply evaluation board for LNB based on the LNBH26LS Data brief Description This evaluation board implements a DC-DC converter based on the LNBH26LS device. It is used to power LNBs inside dish antennas to receive satellite TV signals. The LNBH26LS 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 LNBH26LS 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 DocID029708 Rev 1 1/4 www.st.com For further information contact your local STMicroelectronics sales office Schematic diagram STEVAL-LNBH04 1 Schematic diagram Figure 1: STEVAL-LNBH04 circuit schematic D2-A LNBOUT- A V - 21 V OUT A 20 UP-A D1- A C2-A LNBH26LS D3-A TVS-A C3-A C5-A 3 LX-A R1 (RSEL) L1-A 9 ISEL DiSEqC 22KHz TTL 16 Byp DSQIN -A 22 C7 Vin Tone enable control 17 Vcc or DSQIN -B 24 12 V DiSEqC C4 ADDR 6 Envelope TTL C1 L1-B 8 SDA 2 I C Bus 7 SCL 5 LX-B D1-B V 11 UP-B V 12 OUT-B - P-GND A GND LNBOUT-B 4 15 C2-B C3-B C5-B TVS-B D3-B D2-B GSPG0809161545SG 2/4 DocID029708 Rev 1