Single Output LNB Supply and Control Voltage Regulator with I2C Interface for Advanced Satellite Set-top Box Designs

The ISL6421A is a highly integrated solution for providing power and control signals from advanced satellite set-top box (STB) modules to the low noise block (LNB). The internal architecture of this device contains a current-mode boost PWM and a low-noise linear regulator, along with the circuitry required for I2C device interfacing and for providing DiSEqC™ standard control signals to the LNB.

Features

• Switch-Mode Power Converter for Lowest Dissipation

- Boost PWM with >92 Efficiency

- Selectable 13V or 18V Outputs

- Digital Cable Length Compensation (1V)

- Vsw tracks Vout ensures low dissipation

• I2C Compatible Interface for Remote Device Control

- Registered Slave Address 0001 00XX

- Fully Functional 3.3V, 5V Operation up to 400kHz

• Built-In Tone Oscillator Factory Trimmed to 22kHz

- Facilitates DiSEqC™ (EUTELSAT) Encoding

- External Modulation input DSQIN

• Internal Over Temperature Protection and Diagnostics

• Internal Overload and Over Temperature Flags (Visible on I2C)

• Output Back-Bias Protection to 24V

• LNB Short-Circuit Protection and Diagnostics

• QFN Package

- Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat No Leads - Product Outline

- Near Chip-Scale Package Footprint

• External Pins to Select 13V/18V Options

• Pb-Free Available (RoHS Compliant)

Applications

• LNB Power Supply and Control for Satellite Set-Top Box