CDMA Receiver Offers Stepped Gain Control

For wireless communications applications, the RF2449 receiver front-end is designed for dual-mode CDMA/FM cellular applications. The device amplifies and downconverts RF signals while providing 30 dB of stepped gain control range. Along with digitally controlled LNA gain, mixer gain, LNA IIP3 and power-down mode, the component features adjustable IIP3 of the LNA and mixer bias current using an off-chip current-setting resistor. The LNA IIP3 can be digitally controlled between two levels to reduce current draw in CDMA standby and other situations not requiring high IIP3. Noise figure, IP3 and other specifications are compatible with the IS-95 Interim Standard for CDMA cellular communications. Applications include CDMA/FM cellular systems, dual-mode AMPS/CDMA, dual-mode TACS/CDMA, general-purpose downconversion and various portable battery-powered equipment. Price is $2.17 each/10,000 in SSOP-24.