Product Description

The RF9908 is a complete upconverter designed for CDMA/FM cellular applications. The IC contains a double-balanced mixer stage and an output buffer amplifier stage. This device may also be used to directly BPSK modulate a carrier. The mixer is a Gilbert cell with emitter degeneration resistors to provide high IP3. The output stage is a class-B, push-pull configuration to reduce the overall current and still provide a good 50Ω output match. The unit operates at 3.6V and does not require any exter nal matching components other than coupling capacitors. This circuit is designed as part of the RFMD CDMA Chip Set, consisting of a Transmit IF AGC Amp, this Transmit Upconverter, a Receive LNA/Mixer, and a Receive IF AGC Amp.

Features

• Supports Dual Mode Operation

• +8dBm Input/Output Intercept Point

• Single 3.6V Power Supply

• Internally Matched Inputs and Outputs

• Buffered Output

• Double-Balanced Mixer

Typical Applications

• CDMA/FM Cellular Systems

• Supports Dual-Mode AMPS/CDMA

• Supports Dual-Mode TACS/CDMA

• Commercial and Consumer Systems

• 3-Cell Battery-Operated Systems