Milpitas, Calif. Intersil released the ISL6422B and ISL6423B low-noise block (LNB) supply and control voltage regulators. These regulators use an I2 C interface to improve system reliability by reporting diagnostics and protecting a satellite set top box (SSTB) against overvoltage, overcurrent, overtemperature and backward current. The regulators feature a supply current of 4.0 mA, a standby current of 1.5 mA and a typical dropout voltage of 0.8 V. The input voltage range of 8 V to 14 V also provides design flexibility, allowing designers to use the existing power rail in most SSTBs.
The ISL6422B and ISL6423B save board space with a 440 kHz switching frequency, which enables the use of smaller capacitors and inductors. The devices also have internal error-feedback-loop compensation which eliminates the need for two capacitors and one resistor. The ISL6422B (dual output) has five current-range settings up to 750 mA and the ISL6423B (single output) has four current-range settings up to 750 mA. This enables SSTB manufacturers to design systems to their specific power budget needs.
These devices feature remote device control and FLT-bar interrupt pin and a built-in tone oscillator, factory trimmed to 22 kHz. A decoder facilitates the use of DiSEqC 2.0 (EutelSat) protocol. An external modulation input also allows the DiSEqC modulation of an externally generated tone protocol, be it the envelope or a 22-kHz modulated stream.
Intersil Corp., 408-432-8888, www.intersil.com