Overview
The LNBH26LPQR, produced by STMicroelectronics, is a monolithic voltage regulator and interface IC designed specifically for analog and digital DUAL satellite receivers, Sat-TV, and Sat-PC cards. This IC provides a complete solution for dual tuner satellite receivers, offering low component count, low power dissipation, and simple design with I²C standard interfacing.
Key Specifications
| Parameter | Description |
|---|---|
| Package | QFN24 (4x4 mm) |
| Input Voltage Range | 8 V to 16 V |
| Output Voltages | 13 V / 18 V (programmable) |
| Efficiency | Typically 93% @ 0.5 A |
| Output Current Limit | Selectable by external resistor, up to 750 mA per channel |
| 22 kHz Tone Generator | Accurate, factory-trimmed, and compliant with DiSEqC standards |
| I²C Interface | 2-wire interface for data transmission and configuration |
| Protection Features | Overload, overtemperature, and short-circuit protection; surge protection with TVS diodes |
| ESD Tolerance | +/- 4 kV on output power pins |
Key Features
- Complete interface between LNB and I²C bus
- Built-in DC-DC step-up 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 (8 programmable levels)
- Accurate built-in 22 kHz tone generator
- Low-drop post regulator and high efficiency step-up PWM with integrated power N-MOS
- Overload and overtemperature internal protection with I²C diagnostic bits
- LNB short-circuit dynamic protection
- Surge protection and TVS diodes for high voltage discharges
- Power-on I²C interface reset and undervoltage lockout
Applications
- STB satellite receivers
- TV satellite receivers
- PC card satellite receivers
Q & A
- What is the primary function of the LNBH26LPQR?
The LNBH26LPQR is a monolithic voltage regulator and interface IC designed for analog and digital DUAL satellite receivers, providing the necessary power supply and 22 kHz tone signalling to the LNB down-converter.
- What is the input voltage range for the LNBH26LPQR?
The input voltage range is from 8 V to 16 V.
- How is the output voltage programmed?
The output voltage can be programmed using 4 + 4 bits of an internal DATA1 register accessible via the I²C bus.
- What protection features does the LNBH26LPQR have?
The IC includes overload, overtemperature, and short-circuit protection, as well as surge protection with TVS diodes.
- How does the 22 kHz tone generator work?
The 22 kHz tone generator is accurate and factory-trimmed, compliant with DiSEqC standards, and can be activated by an external 22 kHz source or through the I²C interface.
- What is the efficiency of the DC-DC step-up converter?
The efficiency is typically 93% at 0.5 A.
- How is the output current limit set?
The output current limit can be set by an external resistor connected to the ISEL pin.
- What is the purpose of the I²C interface?
The I²C interface is used for data transmission and configuration between the main microprocessor and the LNBH26LPQR.
- What kind of ESD tolerance does the LNBH26LPQR have?
The LNBH26LPQR has +/- 4 kV ESD tolerance on output power pins.
- How does the undervoltage lockout function work?
The undervoltage lockout disables the whole circuit when the supplied VCC drops below a fixed threshold (typically 4.7 V), and the I²C interface becomes operative once VCC rises above 4.8 V.
