STMicroelectronics LNBP9LIT

Overview

LNBP9LIT from STMicroelectronics is a monolithic linear LNB supply and control voltage regulator in IPPAK package, designed for satellite receiver front-ends to deliver 13 V or 18 V (typ.) regulated output with integrated 22 kHz tone generation, 500 mA guaranteed output current, and 3-state EN/VSEL logic control for remote polarization switching. It enables analog/digital satellite receivers to power and command LNB down-converters over coaxial cable.

For engineers reviewing the LNBP9LIT datasheet, LNBP9LIT pinout, LNBP9LIT application, or LNBP9LIT equivalent, this device supports DiSEqC™-compatible LNB control, fast oscillator startup for tone encoding, thermal and short-circuit protection, and single-supply operation at ≥22 V - critical for satellite set-top box and integrated receiver-decoder (IRD) designs.

Technical Context

The LNBP9LIT integrates a factory-trimmed 22 kHz oscillator (20–24 kHz, 50% duty cycle, 10 µs typical rise/fall time) directly controlled by the TEN pin, eliminating external timing components. Its 3-state EN/VSEL input selects 13 V (LOW), 18 V (HIGH), or shutdown (high-impedance), enabling polarization switching in LNBs via DC voltage level.

As an IPPAK-packaged linear regulator, it uses a single 22–25 V input (VCC pin), with internal connection of VCC1/VCC2, and delivers regulated output with ±150 mV load regulation (50–500 mA) and ±40 mV line regulation. Thermal shutdown activates at 165 °C with 25 °C hysteresis, and output current limiting is fixed at 550–850 mA.

Key Specifications

Pinout & Package

LNBP9LIT is housed in the IPPAK through-hole package (10-pin, 2.3 mm height), with exposed tab electrically connected to GND. This package enables robust thermal coupling to chassis or heatsink while maintaining mechanical stability in consumer satellite equipment.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LNB supply and control applications.

Compared with LNBP8LIT, LNBP9LIT reduces system BOM and layout complexity by integrating the 22 kHz oscillator; compared with LNBP11LIT, it trades DFN8 thermal efficiency and cable compensation for proven IPPAK ruggedness and simpler single-supply implementation in cost-sensitive consumer IRDs.

Availability

LNBP9LIT is available at Aetrix Electronics and suitable for satellite receiver design, digital set-top box production, and integrated receiver-decoder (IRD) manufacturing requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for LNBP9LIT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, delivering automotive, industrial, and consumer ICs with emphasis on power management, analog, and smart power solutions.

The LNBP series belongs to ST's satellite front-end power management product line, engineered specifically for LNB supply and DiSEqC™ control in analog/digital satellite receivers - balancing integration, protection, and ease of MCU interfacing.

FAQ

What is the function of the TEN pin on LNBP9LIT?

The TEN (Tone Enable) pin is a logic input that activates the internal 22 kHz oscillator when driven HIGH. When asserted, it generates a factory-trimmed 22 kHz ±2 kHz square wave modulated onto the OUTPUT pin, enabling DiSEqC™ band switching without external components. The oscillator starts within microseconds and maintains 50% duty cycle and clean 10 µs edges to avoid RF interference.

Can LNBP9LIT operate from a 12 V input supply?

No. LNBP9LIT requires a minimum 22 V DC input on the VCC pin, as specified in its operating ratings and absolute maximums. Supplying below 22 V risks failure to regulate 18 V output or sustain 500 mA load, especially under worst-case line/load conditions. The internal pass transistor dropout necessitates ≥4 V headroom above the selected output voltage.

How does the EN/VSEL pin control output voltage and shutdown?

EN/VSEL is a 3-state logic input: <0.8 V (LOW) selects 13 V output for vertical polarization; >1.8 V (HIGH) selects 18 V for horizontal polarization; high-impedance or 1.2–1.8 V range forces shutdown (0 V output). This allows a single MCU GPIO to manage both LNB power state and polarization - no pull-up/pull-down resistors needed for default states.

Is thermal derating required for LNBP9LIT in enclosed IRD chassis?

Yes. With R_thJA = 35 °C/W on a 2s2p PCB, LNBP9LIT dissipates up to 3.5 W at 500 mA and 23 V input (23 V − 13 V × 0.5 A). In sealed enclosures, ambient temperature rise may push junction temperature near 125 °C operational limit. Use of a grounded metal chassis as heatsink or addition of forced airflow reduces R_thJA and avoids thermal shutdown during sustained operation.