LFC789D25CPWG4 Description

A dual linear FET controller called the LFC789D25CPWG4 makes it easier to create dual power supply. A low-dropout regulator is implemented by the device's two independent controllers, each of which drives an external MOSFET. A tracking regulator, which is frequently required for termination schemes, can be created by programming the second controller to regulate any desired output voltage via a reference input pin while the first controller is programmed to regulate a fixed 2.5-V output. Additionally, the controllers can control the output voltages to a maximum tolerance of ±2% across temperature and load due to the ease with which the heating effects of the external FETs can be easily isolated from the controllers.

The LFC789D25CPWG4 offers designers a wide range of options when it comes to choosing external parts and topologies to satisfy their unique power-supply requirements. The regulator's designer can create one with as much current capacity as the external MOSFET and power supply permit by using the right heat sinking. Furthermore, by carefully choosing the power MOSFET, it is possible to get very low dropout because the regulator's dropout is simply calculated as the sum of the external power MOSFET's RDS(on) and the load current.

The 8-pin SOIC and space-saving TSSOP packaging of the LFC789D25CPWG4 allows for operation between 0°C and 70°C.

LFC789D25CPWG4 Features

• Great Design Flexibility With Minimal External Components

• Applications: High-Current, Low-Dropout Regulators for:

? DDR/RDRAM Memory Termination

? Motherboards

? Chipset I/O

? GTLP Termination

• Two Independent Controllers for Regulation of:

? Fixed 2.5-V and an Adjustable Output

? ±2% (Max) Regulation Across

• Temperature and Load (1 mA to 3 A)

• Adjustable Output Can Be Set Via an External Reference Pin, Allowing for the Creation of a Tracking Regulator

LFC789D25CPWG4 Applications

• As a buffer

• RF amplifiers

• Cascade amplifiers

• A voltage variable resistor

• Oscillator circuits

• Low-frequency amplifiers

• Digital circuits