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 64 of 160
should resume from its suspended mode, if necessary, and service the external event that triggered the
suspended USB device to signal the host. Remote wake-up is accomplished using electrical signaling described in
the Universal Serial Bus Revision 2.0 specification [8].
When the USB enters suspended state, the average VCC module current consumption of LISA-U series module is
~400 µA higher then when the USB is not attached to a USB host.
If power saving is disabled by AT+UPSV=0 and the LISA-U series module is attached to a USB host as USB device,
is configured and is not suspended, the average VCC module current consumption in fixed active mode is
increased to ~40 mA.
1.9.3.3 USB application circuit
Since the module acts as a USB device, the USB supply (5.0 V typ.) must be provided to VUSB_DET by the
connected USB host. The USB interface is enabled only when a valid voltage as USB supply is detected by the
VUSB_DET input. Neither the USB interface, nor the whole module is supplied by the VUSB_DET input: the
VUSB_DET senses the USB supply voltage and absorbs few microamperes.
The USB_D+ and USB_D- lines carry the USB serial data and signaling. The lines are used in single ended mode
for relatively low speed signaling handshake, as well as in differential mode for fast signaling and data transfer.
USB pull-up or pull-down resistors on pins USB_D+ and USB_D- as required by the Universal Serial Bus Revision
2.0 specification [8] are part of the USB pad driver and do not need to be externally provided.
External series resistors on pins USB_D+ and USB_D- as required by the Universal Serial Bus Revision 2.0
specification [8] are also integrated: characteristic impedance of USB_D+ and USB_D- lines is specified by the
USB standard. The most important parameter is the differential characteristic impedance applicable for
odd-mode electromagnetic field, which should be as close as possible to 90 differential: signal integrity may
be degraded if the PCB layout is not optimal, especially when the USB signaling lines are very long.
LISA-U series
VBUS
D+
D-
GND
18
VUSB_DET
27
USB_D+
26
USB_D-
GND
C1
USB DEVICE
CONNECTOR
D1 D2 D3
Figure 34: USB Interface application circuit
Reference
Description
Part Number - Manufacturer
D1, D2, D3
Very Low Capacitance ESD Protection
PESD0402-140 - Tyco Electronics
C2
100 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R61A104KA01 - Murata
Table 29: Component for USB application circuit
If the USB interface is not connected to the application processor, it is highly recommended to provide
direct access to the VUSB_DET, USB_D+, USB_D- lines for execution of firmware upgrade over USB
and for debug purpose: testpoints can be added on the lines to accommodate the access. Otherwise, if
the USB interface is connected to the application processor, it is highly recommended to provide direct
access to the RxD, TxD, CTS and RTS lines for execution of firmware upgrade over UART and for debug
purpose. In both cases, provide as well access to RESET_N pin, or to the PWR_ON pin, or enable the