The small cell is the next big thing in cellular infrastructure. Small cells will be deployed to make LTE and other 3G wireless services more widely available and to take the load off the existing macrocells. Maxim Integrated’s MAX2580 RF transceiver implements these picocells and femtocells (Fig. 1).
The MAX2580 integrates a complete 2x2 multiple-input multiple-output (MIMO) RF front end, two fractional-N phase-locked loop (PLL) synthesizers, and all high-speed data converters (Fig. 2). The dual transmit and receive channels communicate with an external baseband processor through JESD207 interfaces. The chip includes all decimation, interpolation, and channel selection filters.
Also, the chip supports frequency division duplex-Long Term Evolution (FDD-LTE) and time division duplex-Long Term Evolution (TDD-LTE), as well as HSPA+. The power amplifier pre-driver delivers 0 dBm. The transceiver supports all LTE bands 1 through 41 and all selectable LTE channel bandwidths from 1.4 MHz to 20 MHz. Support for 3G WCDMA modes is included.
A complete production-ready small-cell reference design uses the MAX2580 and Freescale’s BSC9132 multi-processor baseband IC. The BSC9132 includes two Power Architecture e500 cores and two StarCore DSP cores along with Freescale’s MAPLE-B2P accelerator platform. It can process 64 simultaneous users and handles 150-Mbit/s downlink rates with 75-Mbit/s uplink rates in a 20-MHz LTE channel. And, the reference design includes a 1-W+ power amplifier and all network management circuitry.
Sampling now, the MAX2580 comes in an 11- by 11-mm quad flat no-lead (QFN) package. The reference design also is available. Production will come online in the second half of 2013.