motorola L72, L9 Theory of Operation

Operational Description

Functional Description

Hawaii Refresh cellular phone operates in GSM, DCS, and CEL & PCS bands. It
provides GPRS class 10, EDGE class 10 and Bluetooth class 2 data support. It
consists of RFMD Prime chipsets, Neptune LTE2, Atlas Ultra-Lite, Bluetooth
module, internal system memory of 512Mbit flash, 128Mbit PSRAM and
removable memory storage in the form of microSD memory card up to 2GB. It
also embedded a 2MP CMOS camera, FM radio and MegaSIM capabilities.

Hardware Interface

The signaling diagram shows a general view of the interfaces involved between
the chips on the RF portion of the radio. RF6027 and RF3178 formed the RFMD
Prime chipset.

Antenna Switch

An internal antenna switch is employed in this design. The antenna switch
routes the appropriate band transmit or receive signal between the antenna and
respective IC. It is controlled by 3 control lines, B1, B2 and B3, coming from the
RF6027.

RF3178

The RF3178 module is a 50Ω input/output, quad-band, dual-mode,
GMSK/8PSK(EDGE) PA module intended for 2.75G radio applications. The
module consists of a dual line-up power amplifier, harmonic filter, and antenna
switch. The antenna switch connects the antenna to any one of four receiver
ports or either low band or high band power amplifier output. The module
contains two RF dies using HBT technology, a silicon die for the power control
and antenna switch controller, and harmonic filters. The module incorporates an
indirect closed loop method for power control. Output power is controlled by
varying the collector voltage. The module does not have a coupler or a power
detector.

RF6027

The RF6027 is a combination Fractional-N synthesizer and signal processing IC,
which also includes RF front end with the VLIF/DC receive IC, constitutes a
quad-band GSM/EDGE transceiver solution. In GSM mode, it offers a fully digital
GMSK modulator for extremely low current consumption. The signal processing
section provides a digital receive filter path. The IF inputs are digitized, filtered
and down converted to base-band I and Q signals. The flexible base-band
interface can be configured for either analog or digital operation. Chip
functionality is controlled through a three-wire SDI bus.

Neptune LTE2

The Neptune LTE2C90 base-band IC is a digital base-band processor for the

2.75G GSM application. The design is derived from HiP7 Neptune LTE with
changes to process, memory configuration, and several module enhancements.
It is a dual-core processor that contains a Synthesizable Onyx DSP core (56600),
an ARM7TDMI-S microcontroller, and custom peripherals. Neptune LTE2C90 is
configured for EDGE applications. Neptune LTE2C90 is available in a 280-pin
MAPBGA package in either a production or development configuration.

The Neptune LTE2 C90 IC is derived from the Neptune LTE IC with the following
key changes:

• CMOS90 (90nm) process technology

• On-chip memory:
– MCU RAM size is 512 KBytes.
– MCU ROM size is 128 KBytes.
– DSP X, Y, and P RAM and ROM sizes (same as LTE)
– 127 K x 24 bits PROM
– 63.75 K x 24 bits PRAM
– 40 K x 16 bits XROM
– 20 K x 16 bits XRAM
– 40 K x 16 bits YROM
– 20 K x 16 bits YRAM

• LEM enhancement for A5/3

• GEM enhancement for GEA-3

Atlas Ultra-Lite

Atlas Ultra-Lite (referred to herein as AUL) is a power management and user
interface product providing general power, audio, and lighting management
functions. AUL is targeted for the GSM/GPRS/EDGE space for non-applications
processor lineups, but it is protocol independent and may fit other applications
due to its modular functionality.