General Description
The MAX2411A performs the RF front-end transmit/receive function in time-division-duplex (TDD) communication systems. It operates over a wide frequency range and is optimized for RF frequencies around 1.9GHz. Applications include most popular cordless and PCS standards. The MAX2411A includes a low-noise amplifier (LNA), a downconverter mixer, a local-oscillator buffer, an upconverter mixer, and a variable-gain power-amplifier (PA) driver in a low-cost, plastic surface-mount package. The MAX2411A’s unique bidirectional, differential IF port reduces cost and component count by allowing the transmit and receive paths to share the same IF filter.
The LNA has a 2.4dB typical noise figure and a -10dBm input third-order intercept point (IP3). The downconvert er mixer has a low 9.2dB noise figure and 4dBm input IP3. Image and local-oscillator filtering are implemented off-chip for maximum flexibility. The PA driver amplifier has 15dB of gain, which can be reduced over a 35dB range. Power consumption is only 60mW in receive mode and 90mW in transmit mode and drops to less than 3µW in shutdown mode.
For applications requiring separate, single-ended IF input and output ports, refer to the MAX2410 data sheet. For applications requiring only a receive function, Maxim offers a low-cost downconverter with LNA (see the MAX2406 data sheet).

Features
♦ Low-Cost Silicon Bipolar Design
♦ Integrated Upconvert/Downconvert Function
♦ Operates from a Single +2.7V to +5.5V Supply
♦ 3.2dB Combined Receiver Noise Figure:
   2.4dB (LNA)
   9.2dB (mixer)
♦ Flexible Power-Amplifier Driver:
   18dBm Output Third-Order Intercept (OIP3)
   35dB Gain-Control Range
♦ LO Buffer for Low LO Drive Level
♦ Low Power Consumption:
   60mW Receive
   90mW Full-Power Transmit
♦ 0.3µW Shutdown Mode
♦ Flexible Power-Down Modes Compatible with MAX2510/MAX2511 IF Transceivers

Applications
   PWT1900
   DECT
   DCS1800/PCS1900
   ISM-Band Transceivers
   PHS/PACS
   Iridium Handsets