BENEFITS and FEATURES

• Wide Operating Range

• Vin = 10V to 55V

• Vgate = -6V to -1.5V

• RF PA Biasing Solution

• Turn on and off sequencing

• Negative gate voltage supply

• Supports GaN and Silicon FETs

• High-speed drain switching

• Autonomous Bias Point Calibration

• Autonomous IDQ(DRAIN) calibration

• Resistor Setpoint Range: 10mA to 2A

• Digitally adjustable ±31% of setpoint in 1% steps

• Space and Cost savings

• Fully integrated gate drive voltage

• High switching frequency: 2.05 MHz

• Integrated FETs and small chip inductor

• 37-pin, 5 mm x 5 mm, 0.4-mm pitch QFN package

• High-Performance Negative Gate Drive Supply

• REGG input voltage: +12V (TYP)

• REGG output voltage: -6V to -1.5V by 732μV step

• REGG output source current: 300mA

• REGG output sink current: -100mA

• REGG output noise: <200μVRMS

• Protection

• UVLO, OVLO, OVP, UVP, OCP, TSD

APPLICATIONS

• Military Radar System

• Civilian Radar System

• RF GaN / GaAs PA Power Supply

GENERAL DESCRIPTION

The ACT43750, part of Qorvo’s RF POL regulator family,

is the last stage of a three-chip radar power supply solution.

This three-stage solution, developed with the

ACT43950, ACT43850, and ACT43750, forms a compact,

complete power supply system for radio frequency

(RF) power amplifiers (PAs) that demand fast transient,

high current pulse loads. The first stage, ACT43950

converts a high voltage dc input voltage into a regulated

dc constant-current (CC) to charge bulk capacitor. The

second stage, ACT43850, regulates the capacitor voltage

into a tightly regulated DC voltage to power the

drain for GaN RF power amplifiers.

The third stage, ACT43750, provides several functions

specifically designed to optimize GaN performance. It

operates either standalone or as the third stage in a

multiple stage power solution. It provides the RF PA

negative gate voltage using an ultra-low noise inverting

buck dc-to-dc regulator with integrated FETs and programmable

voltage reference. It provides the required

GaN power up and power down sequencing between

the drain and gate voltages. All GaN RF PAs require

calibrating the gate voltage to set the desired operating

point. The ACT43750 automatically calibrates and

stores the optimal gate voltage. This operating point

changes with time and temperature. The IC can recalculate

and adjust the optimal gate voltage in the field

without waiting for a maintenance cycle. The ACT43750

also enables drain switching in pulsed radar applications.

The ACT43750 is available in a 37-pin, 5 mm x 5 mm,

0.4 mm pitch QFN package.