TPS65235RUKR Description

The TPS65235 is a monolithic voltage regulator with an I2C interface that is made for analog and digital satellite receivers. Its purpose is to supply the 22-kHz tone signal and the 13-V to 18-V power supply to the LNB down converter in the antenna dish or to the multiswitch box. With a minimal component count, low power consumption, straightforward design, and I2C standard interface, it provides a comprehensive solution.

High power efficiency is a feature of TPS65235. A 140-m power MOSFET with a variable switching frequency of either 1 MHz or 500 kHz is integrated into the boost converter. To reduce power loss, the linear regulator's drop out voltage is set to 0.8 V. There are various ways to produce the 22 kHz signal using TPS65235. Even with no loading, an integrated linear regulator with a push-pull output stage generates a 22-kHz tone signal overlaid at the output. With an accuracy of 10%, an external resistor can be used to configure the linear regulator's current limit. For system monitoring, the full set of diagnostics read via I2C is provided.

TPS65235RUKR Features

• Complete integrated solution for LNB and I2C interface

• DiSEqC 2.x and DiSEqC 1.x compatible

• Supports 5-V, 12-V, and 15-V power rail

• Up to 1000-mA accurate output current limit adjustable by external resistor

• Boost switch peak current limit proportional to LDO current limit

• Boost converter with 140-mΩ low Rds(on) internal power switch

• Boost switching frequency 1-MHz or 500-kHz selectable

• Dedicated enable pin for non-I2C application

• Low drop output LDO with push-pull output stage for VLNB output

• Built-in accurate 22-kHz tone generator and external tone input support

• Supports both external 44-kHz and 22-kHz tone input

• Adjustable soft-start and 13-V to 18-V voltage transition time

• 650 mV to 750-mV, 22-kHz tone amplitude selection

• I2C registers accessible with EN low

• Short circuit dynamic protection

• Diagnostics for output voltage level, DiSEqC tone input and output, current level, and cable connection

• Thermal protection available

• 20-lead WQFN 3-mm × 3-mm (RUK) package

TPS65235RUKR Applications

• Set top box satellite receiver

• TV satellite receiver

• PC card satellite receiver

• Satellite TV