REP020: Dual-band dual-mode FE IC operating at universal 210MHz IF

Rapid engineering prototypes are actual circuits that Maxim application engineers build in the lab and conduct product testing. They are the starting point for new RF engineering designs. They are not intended as assessment testing tools.

Goal: Apply and test this dual-band three-mode CDMA receiver front-end IC under all 210MHz IF.

MAX2323 provides a digital IF output port, using a universal 210MHz IF. The mixer gains of both modes can meet the sensitivity requirements of high-performance receivers. At the same time, its IP2 performance and other related parameters can meet the requirements of 1 in CDMA mobile phones. /2 IF and additional interference requirements provide sufficient margin. In this application, MAX2323 was successfully used in the CDMA dual-band dual-mode mobile phone front-end design and tested. The circuit modification required for this design is to retune the FM and cellular/PCS mixers to 210MHz IF.

The MAX2323 low-noise amplifier and mixer is designed for dual-band CDMA cellular handsets, but it can also be used in dual-band TDMA, GSM, EDGE, or WCDMA applications. The difference from its previous generation (MAX2320) is that this cellular band LNA adds a third "medium gain" state to improve switching hysteresis margin. It also uses a smaller package (28-QFN) and provides a higher third-order input intercept point.

Block diagram of the receive-path application
Schematic of the MAX2323 evaluation kit (PDF, 58kB)
Bill of materials, part 1
Bill of materials, part 2