REP018: Dual-band dual-mode FE IC operating at universal 183.6MHz 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 183MHz IF.

The MAX2323 has a single-ended and a differential IF output port. For the universal 183MHz IF, the gain of the cellular/PCS mixer can still meet the requirements of excellent receiver sensitivity, while its IP2 performance and other related parameters can meet the requirements of 1/2 IF and other interference in CDMA mobile phones. Provide sufficient margin. In this application, MAX2323 was successfully used in the CDMA dual-band dual-mode mobile phone front-end design and tested for this purpose. The circuit modification required for this design is to retune the FM and cellular/PCS mixers to 183MHz 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.

Schematic of the MAX2323 evaluation kit (PDF, 61kB)
Bill of materials, part 1
Bill of materials, part 2