Integration Manual
Table Of Contents
- Preface
- Contents
- 1 System description
- 1.1 Overview
- 1.2 Architecture
- 1.3 Pin-out
- 1.4 Operating modes
- 1.5 Power management
- 1.6 System functions
- 1.7 RF connection
- 1.8 (U)SIM interface
- 1.9 Serial communication
- 1.10 DDC (I2C) interface
- 1.11 Audio Interface
- 1.12 General Purpose Input/Output (GPIO)
- 1.13 Reserved pins (RSVD)
- 1.14 Schematic for LISA-U series module integration
- 1.15 Approvals
- 2 Design-In
- 2.1 Design-in checklist
- 2.2 Design Guidelines for Layout
- 2.2.1 Layout guidelines per pin function
- 2.2.2 Footprint and paste mask
- 2.2.3 Placement
- 2.3 Thermal aspects
- 2.4 Antenna guidelines
- 2.5 ESD precautions
- 3 Features description
- 4 Handling and soldering
- 5 Product Testing
- Appendix
- A Migration to LISA-U2 series wireless modules
- B Glossary
- Related documents
- Revision history
- Contact
LISA-U series - System Integration Manual
3G.G2-HW-10002-A3 Preliminary System description
Page 10 of 160
1.2.1 Functional blocks
LISA-U series modules consist of the following internal functional blocks: RF section, Baseband and Power
Management Unit section.
LISA-U1 series RF section
A shielding box includes the RF high-power signal circuitry, namely:
Front-End Module (FEM) with integrated quad-band 2G Power Amplifier and antenna switch multiplexer
Two single-band 3G HSPA/WCDMA Power Amplifier modules with integrated duplexers
The RF antenna pad (ANT) is directly connected to the FEM, which dispatches the RF signals according to the
active mode. For time-duplex 2G operation, the incoming signal at the active Receiver (RX) slot is applied to
integrated SAW filters for out-of-band rejection and then sent to the appropriate receiver port of the RF
transceiver. During the allocated Transmitter (TX) slots, the low level signal coming from the RF transceiver is
enhanced by the 2G power amplifier module and then directed to the antenna through the FEM. The 3G
transmitter and receiver are instead active at the same time due to frequency-domain duplex operation. The
switch integrated in the FEM connects the antenna port to the passive duplexer which separates the TX and RX
signal paths. The duplexer itself provides front-end RF filtering for RX band selection while combining the
amplified TX signal coming from the fixed gain linear power amplifier.
In the same shielding box that includes the RF high-power signal circuitry there are all the low-level analog RF
components, namely:
Dual-band HSPA/WCDMA and quad-band EDGE/GPRS/GSM transceiver
Voltage Controlled Temperature Compensated 26 MHz Crystal Oscillator (VC-TCXO)
Low Noise Amplifier (LNA) and SAW RF filters for 2G and 3G receivers
While operating in 3G mode, the RF transceiver performs direct up-conversion and down-conversion of the
baseband I/Q signals, with the RF voltage controlled gain amplifier being used to set the uplink TX power. In the
downlink path, the external LNA enhances the RX sensitivity while discrete inter-stage SAW filters additionally
improve the rejection of out-of-band blockers. An internal programmable gain amplifier optimizes the signal
levels before delivering to the analog I/Q to baseband for further digital processing.
For 2G operations, a constant gain direct conversion receiver with integrated LNAs and highly linear RF
quadrature demodulator are used to provide the same I/Q signals to baseband as well. In transmission mode, the
up-conversion is implemented by means of a digital sigma-delta transmitter or polar modulator depending on
the modulation to be transmitted.
In all the modes, a fractional-N sigma-delta RF synthesizer and an on-chip 3.296-4.340 GHz voltage controlled
oscillator are used to generate the local oscillator signal.
The frequency reference to RF oscillators is provided by the 26 MHz VC-TCXO. The same signal is buffered to the
baseband as a master reference for clock generation circuits while operating in active mode.
LISA-U2 series RF section
A shielding box contains the RF high-power signal circuitry, including:
Multimode Single Chain Power Amplifier Module used for 3G HSPA/WCDMA and 2G EDGE/GSM operations
Power Management Unit with integrated DC/DC converter for the Power Amplifier Module
The RF antenna pad (ANT) is directly connected to the main antenna switch, which dispatches the RF signals
according to the active mode. For time-duplex 2G operation, the incoming signal at the active Receiver (RX) slot
is applied by the main antenna switch to the duplexer SAW filter bank for out-of-band rejection and then sent to
the appropriate receiver port of the RF transceiver. During the allocated Transmitter (TX) slots, the low level
signal coming from the RF transceiver is enhanced by the power amplifier and then directed to the antenna pad
through the main antenna switch. The 3G transmitter and receiver are active at the same time due to frequency-
domain duplex operation. The switch integrated in the main antenna switch connects the antenna port to the
duplexer SAW filter bank which separates the TX and RX signal paths. The duplexer itself provides front-end RF
filtering for RX band selection while combining the amplified TX signal coming from the power amplifier.