Overview
The LNBH26SPQR, produced by STMicroelectronics, is a dual Low Noise Block (LNB) supply and control IC designed for satellite receiver applications. This monolithic voltage regulator and interface IC is specifically tailored for analog and digital dual satellite receivers, Sat-TV, and Sat-PC cards. It provides a complete solution for dual tuner satellite receivers with a low component count, low power dissipation, and simple design, utilizing I²C standard interfacing.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | QFN24 (4 x 4) | - |
| Packing | Tape and reel | - |
| DC Power Supply Input Voltage | -0.3 to 20 | V |
| DC Input Voltage (VUP) | -0.3 to 40 | V |
| Output Current (IOUT) | Internally limited | mA |
| Output Voltage (VOUT) | -0.3 to 40 | V |
| Logic Input Pin Voltage | -0.3 to 7 | V |
| Operating Junction Temperature | -25 to 125 | °C |
| Maximum Junction Temperature | 150 | °C |
| Efficiency (typ. @ 0.5 A) | 93% | - |
| Output Voltage Levels | 15 programmable levels | - |
Key Features
- Complete interface between LNB and I²C bus
- Built-in DC-DC converter for single 12 V supply operation with high efficiency
- Selectable output current limit by external resistor
- Compliant with main satellite receiver output voltage specifications (15 programmable levels)
- Accurate built-in 22 kHz tone generator
- Low drop post regulator and high efficiency step-up PWM with integrated power NMOS
- Low power mode (LPM) to reduce dissipation
- Overload and overtemperature internal protection with I²C diagnostic bits
- LNB short-circuit dynamic protection
- +/- 4 kV ESD tolerant on output power pins
- Bi-directional DiSEqC™ 2.0 interfacing with built-in 22 kHz tone detector
Applications
- STB satellite receivers
- TV satellite receivers
- PC card satellite receivers
- Dual tuner satellite receivers
- Sat-TV and Sat-PC cards
Q & A
- What is the primary function of the LNBH26SPQR IC?
The LNBH26SPQR is a dual LNB supply and control IC designed to provide the 13/18 V power supply and the 22 kHz tone signaling to the LNB down-converter in satellite receiver applications.
- What is the package type and packing method of the LNBH26SPQR?
The LNBH26SPQR comes in a QFN24 (4 x 4) package and is packed in tape and reel format.
- What is the efficiency of the built-in DC-DC converter?
The built-in DC-DC converter has a typical efficiency of 93% at 0.5 A.
- How can the output current limit be set?
The output current limit can be set by an external resistor connected to the ISEL pin, using the equation provided in the datasheet.
- What is the purpose of the LPM (low power mode) function?
The LPM function reduces total power loss by disabling the 22 kHz tone output for long periods, reducing the drop voltage across the integrated LDO regulator.
- How does the LNBH26SPQR handle overtemperature protection?
The IC is protected against overheating; when the junction temperature exceeds 150 °C, the step-up converter and both linear regulators are shut off, and the diagnostic OTF bit is set to “1”.
- What is the role of the 22 kHz tone generator and detector in the LNBH26SPQR?
The IC includes an accurate built-in 22 kHz tone generator and a tone detector to support DiSEqC™ 2.0 interfacing.
- How is the output voltage level programmed in the LNBH26SPQR?
The output voltage level can be easily programmed using 4 + 4 bits of an internal DATA1 register accessible via the I²C bus.
- What diagnostic functions are available via the I²C bus?
The LNBH26SPQR provides 14 diagnostic internal functions via the I²C bus, including overtemperature status, input voltage power not good function, overload protection status, and more.
- What kind of surge protections are included in the LNBH26SPQR?
The IC includes surge protections and TVS diodes, with each device section directly connected to the antenna cable and protected against atmospheric surges.
- How does the LNBH26SPQR support bi-directional DiSEqC™ 2.0 interfacing?
The IC supports bi-directional DiSEqC™ 2.0 interfacing with an output R-L filter and a BPSW pin to bypass the output RL filter during transmission mode.
