AN3115 Datasheet, PDF (1/28 Pages) STMicroelectronics – LNB power supply based on the LNBH23L supply and control IC with step-up and I²C interface

AN3115
Application note
LNB power supply based on the LNBH23L
supply and control IC with step-up and I²C interface
Introduction
This application note is intended to provide additional information and suggestions for the
correct use of the LNBH23L device. All waveforms shown are based on the demonstration
board order code STEVAL-CBL007V1 described in Section 3.
The LNBH23L is an integrated solution for supplying/interfacing satellite LNB modules. It
gives good performance in a simple and cheap way, with minimum external components
necessary. It includes all functions needed for LNB supplying and interfacing, in accordance
with international standards. Moreover, it includes an I²C bus interface and, thanks to a fully
integrated step-up DC-DC converter, it functions with a single input voltage supply ranging
from 8 V to 15 V.
Figure 1. LNBH23L internal block diagram
ISEL
TTX
ADDR SDA SCL Vcc Byp Vcc-L
LX
P-GND
Rsense
Vup
VoRX
VoTX
TTX
EXTM
DSQIN
EN
VSEL
VSEL
TTX
VOUT Control
TEN
Linear Post-reg
+Protections
+Diagnostics
FB
22KHz
Oscill.
A-GND
Preregulator
+U.V.lockout
+P.ON reset
EN
I² C interface
I²C OLF and OTF
Diagnostics
Pull Down
Controller
LNBH23L
PDC
January 2011
Doc ID 16830 Rev 3
1/28
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