ACT43750

RFPoL (Point of Load) Drain-Switch Driver / Gate-Bias Regulator

Key Features

  • State-machine logic:
    • Auto-calibration anytime in the field after shipment
    • On-PCB RSNS-base, digital ±31% in 1% step program
    • RF GaN PA sequencing / protections
  • Drain-switch, ON and OFF the pre-regulated DC supply:
    • Drain supply input voltage: 10 to 55 V
    • TRISE / TFALL: 30 ns (typ)
  • Gate-bias regulator:
    • Output voltage: -6 to -1.5 V w/ 732 µVSTEP
    • Output source current: 300 mA, (peak 500mA)
    • Low-noise output: < 200 µVRMS

The ACT43750 radar power supply integrates a ~30 ns fast drain-switch, a 13-bit DAC base gate regulator and RFPAs (radio frequency power amplifiers) for sequencing into one standalone solution. Each RFPA drain node is switched ON or OFF by the DSW50 block, which takes a pre-regulated 10V-55V supply. In tandem with a dedicated state machine, the REGG block provides each RFPA gate node with a low noise supply for sequencing and protection. The state machine automates RFPA gate-voltage calibration control at the proper VGATE - IDQ bias point.

Along with the ACT43950 and ACT43850, the family offers a compact, complete power supply system for radar systems demanding a fast transient and high-current pulse load. The ACT43950 works as a transmission phase transient-shock-averaging block, replacing a larger power-line filter(s) at a primary source. The ACT43850 RFPoL (RF point of load) provides a low-noise, fast-responding DC output supply for RFPA drain nodes. When used together, the ACT43950 and ACT43850 significantly reduce the size of bulk capacitors at the PA drain node.

The ACT43750 is available in a 40-pin, 5 mm x 5 mm, 0.4-mm pitch QFN package with three (3) pins removed to maintain creepage distance(s) for high voltage power rails.

Typical Applications

    • RF GaN / GaAs PA Power Supply
    • Military Radar Systems
    • Civilian Radar Systems
    • Satellite Communications - Uplink