LNBH25L is an LNB supply and control IC with step-up and I²C interface. It features a built-in DC-DC converter for single 12V supply operation and high efficiency (typ. 93% @ 0.5A). The output current limit can be selected by an external resistor. The IC is compliant with main satellite receiver output voltage specifications and has an accurate built-in 22kHz tone generator. It also has a low-drop post regulator and high efficiency step-up PWM with integrated power N-MOS, allowing for low power losses. The IC provides overload and overtemperature internal protection with I²C diagnostic bits and LNB short-circuit dynamic protection.
The LNBH25L is a monolithic voltage regulator and interface IC designed for analog and digital satellite receivers and PC cards. It integrates a DC-DC step-up converter and an I2C interface to provide the 13 V or 18 V power supply and 22 kHz tone signaling required for LNB down-converters.
The device features a built-in DC-DC converter that operates from a single 8 V to 16 V supply, achieving high efficiency with a typical output of 93% at 0.5 A. It includes selectable output current limits, accurate 22 kHz tone generation compliant with DiSEqC standards, and various protection mechanisms such as overload, overtemperature, and short-circuit protection.
| Supply Voltage Range | 8 V to 16 V |
|---|---|
| Efficiency | typ. 93% @ 0.5 A |
| Package Type | QFN24 (4 x 4) |
| Undervoltage Lockout Threshold | 4.7 V typ. |
| Soft-start Time (13V) | 4ms typ. |
| Soft-start Time (18V) | 6 ms typ. |
| Max Output Current Limit | 750 mA |
The typical efficiency is 93% at a 0.5 A load.
The current limit threshold is set by an external resistor connected to the ISEL pin.
The interface disables when the supply voltage drops below 4.7 V typically.