REP003: Cellular Front-End ICs in Automotive Applications

Rapid engineering prototypes are actual circuits built and tested by Maxim application engineers in our labs. They are the starting point for new RF engineering designs. They are not intended as assessment testing tools.

Purpose: To determine the non-destructive operating temperature range of a dual-band triple-mode front-end IC.

In an automotive navigation system application, the design required custom testing of the MAX2323 over an extended temperature range of +110°C . The primary test goal is to determine the circuit's normal recovery performance, specifically from high temperature to room temperature, without significant deterioration in performance. Please note that you will initially find the soft plastic components (jumpers) on the board melting, but this can be improved by using a local thermal control source.

The MAX2323 low-noise amplifier (LNA) and mixer is designed specifically for dual-band CDMA cellular phones, but it can also be used in dual-band TDMA, GSM, EDGE, or WCDMA systems. The difference between it and its replacement (MAX2320) is that it adds a third "intermediate gain" state specifically for cellular band LNAs to improve switching hysteresis margin. Likewise, its package (28-QFN) is smaller and it also improves the input third-order intercept point.

Performance measurements at 25°C and 100°C
PCS mixer measurement test setup
Schematic of MAX2323 evaluation kit
Bill of materials, part 1
Bill of materials, part 2
Bill of materials, part 3