Single low-noise downconversion designed for analog and digital satellite receiversVoltage regulator(LNBR) is a monolithic switching linear regulator designed to deliver power and interface signals over coaxial cable to an LNB downconverter. The A8303 and A8303-1 have an internal boost switch and compensation circuitry, requiring only a few external components. High switching frequencies are chosen to minimize passive filter component size and further reduce costs. High-level component integration ensures ultra-low noise and ripple patterns.
In response to Japanese market demand, the A8303-1 includes an 11.667 V setting.
A8303and the A8303-1 feature an efficient design philosophy and utilize Allegro's advanced BCD process. The integrated boost switch is optimized to minimize switching and static losses. To further improve efficiency, the voltage drop of the tracking regulator has been minimized.
To facilitate DiSEqC™ communication, tone control pins are also provided for internal generation of 22™ kHz tone switch gating. The device provides a comprehensive set of fault registers that meet all common criteria, including overcurrent, thermal shutdown, undervoltage, and poor power supply.
In addition, design methods and construction ensure the highest level of stability against transients and component failures. The device uses a 2-wire bidirectional serial interface, with I2C™ standard compatible and operating frequency up to 400 kHz.
The A8303 and A8303-1 are available in a lead-free (Pb) package.
- Integrated boost MOSFETs, current sensing, and current compensation.
- Stable compared to low-profile ceramic boost capacitors
- New 11.67 (A8303-1) and 15.67 V output settings are also included for Japanese market design requirements.
- The adjustable LNB output current is limited to 250 to 950 mA.
- It can meet a wide range of application needs.
- Maximize component size to meet a variety of application needs.
- For startup, reconfiguration, and continuous output (maximum depends on PCB thermal design).
- The boost peak current limit range is set by LNB current limit.
- 8-stage programmable LNB output voltage (DAC).
- LNB overcurrent limiter with shutdown timer.
- Static LNB current limiting reliably initiates a wide range of loads
- Tracking boost converters minimize power dissipation.
- LNB transient time configurable by an external capacitor.
- The LNB push-pull output stage maintains 13→18 V and 18→13 V transient times, even with high capacitive loads.
- The built-in 22 kHz tone oscillator facilitates DiSEqC™ tone encoding, even when™ there is no load.
- No additional external components are required to produce tones
- Diagnostic functions: PNG, TDET
- Dynamic tone detection amplitude and frequency transmit/receive thresholds.
- Extensive protection functions: UVLO, OCP, TSD, CPOK 2-line I2C-compatible interface.