Power Management IC for the SkyBlue™ System

The SKY87021-11 is a high-efficiency RF front-end power management IC for APT RF power amplifier (PA) applications in portable battery powered devices. This IC includes a high-efficiency DC-DC voltage converter capable of delivering 450 mA at 11 V with a 4.5 V reference supply to provide a user-programmable RF PA APT supply for a 2.5 V to 5.5 V input range.

The SKY87021-11 also provides an additional 4.5 V bias supply for RF PA operation. This bias voltage output can supply load currents up to 3 mA and is available whenever the device is enabled. When the device is disabled, the 4.5 V bias supply is shut down. This device has over-voltage, over-current, shorted circuit, and thermal shutdown protection to protect the device and system under adverse operating conditions.

The SKY87021-11 is capable of supporting HPUE front-end modules and is controlled with a MIPI RFFE 2.0 compliant interface with 8-bit output voltage programming resolution.

The SKY87021-11 is available in a 16-pin, 1.991 mm x 1.991 mm Chip Scale Package (CSP).


    • Input voltage range: 2.5 V to 5.5 V
    • High voltage boost supply:
      • Output voltage range from Bypass to 11V
      • Output current up to 450mA
      • High efficiency: 90% typical (VIN=3.8 V, VOUT=9.5 V, ILOAD>110 mA)
      • Fast voltage transition response 570 mV/μs
      • Optimized for small external components
        • For HPUE application, 1.5 μH inductor, 2x1.0 μF output capacitor
        • For non-HPUE application: 1.5 μH/2.2 μH, 1.0 μF output capacitor
        • High 2.25 MHz switching frequency
      • Shutdown load disconnect
      • Fast load transient response, less than 20 μs
      • Over temperature, over voltage and short circuit protection
    • Low voltage ÷2 step-down function: Output current up to 30 mA
    • 4.5 V, 3 mA PA bias supply output
    • MIPI RFFE interface for setup and control: 8-bit output voltage programming resolution
    • Small footprint CSP (16-ball, 1.991 mm x 1.991 mm) package (MSL1, 260 °C per JEDEC J-STD-020)

Images & Diagrams


    • Min. VIN (V)
    • 2.5
    • Max. VIN (V)
    • 5.5
    • Min. VOUT (V)
    • 2.5
    • Max. VOUT (V)
    • VccPA
    • IOUT (mA)
    • TBD
    • fOSC (kHz)
    • TBD
    • Typ. IQ (μA)
    • TBD
    • Package
    • CSP, 16-ball
    • Package (mm)
    • 1.991 x 1.991 x 0.695