The SKY77447 Load-Insensitive Power Amplifier (LIPA®) module is a fully matched 10-pad surface mount module developed for Wideband Code Division Multiple Access (WCDMA) applications. This small and efficient module packs full 1850–1910 MHz bandwidth coverage into a single compact package. Because of high efficiencies attained throughout the entire power range, the SKY77447 delivers unsurpassed talk-time advantages. The SKY77447 meets the stringent spectral linearity requirements of High Speed Downlink Packet Access (HSDPA) data transmission with high power added efficiency. A directional coupler integrated into the module eliminates the need for any external coupler.
The single Gallium Arsenide (GaAs) Microwave Monolithic Integrated Circuit (MMIC) contains all active circuitry in the module. The MMIC contains on-board bias circuitry, as well as input and interstage matching circuits. Output match into a 50-ohm load is realized off-chip within the module package to optimize efficiency and power performance.
The SKY77447 operates as a load-insensitive power amplifier providing high linearity in the presence of high RF mismatch up to 3:1 VSWR. The module is manufactured with Skyworks’ InGaP GaAs Heterojunction Bipolar Transistor (HBT) BiFET process that provides for all positive voltage DC supply operation while maintaining high efficiency and good linearity. No VREF voltage is required. Power down is accomplished by setting the voltage on VEN to zero volts. No external supply side switch is needed as typical “off” leakage is a few microamperes with full primary voltage supplied from the battery.
- Low voltage positive bias supply: 3.0 V to 4.6 V
- Good linearity
- High efficiency at all power levels: 19% @ 15 dBm
- Large dynamic range
- Small, low profile package: 4 x 3 x 0.9 mm, 10-pad configuration
- Power down control
- Supports low collector voltage operation
- Digital VEN
- No VREF required
- Digital or analog control
- Integrated Directional Coupler