TOBY-L2 and MPCI-L2 series - System Integration Manual
UBX-13004618 - R07
Advance Information
Design-in
Page 134 of 158
2.17
Design-in checklist
This section provides a design-in checklist.
2.17.1
Schematic checklist
The following are the most important points for a simple schematic check:
DC supply must provide a nominal voltage at
VCC
/
3.3Vaux
pin within the operating range limits.
DC supply must be capable of supporting both the highest peak and the highest averaged current
consumption values in connected-mode, as specified in the
TOBY-L2 series Data Sheet
[1] or in the
MPCI-L2 series Data Sheet
VCC
/
3.3Vaux
voltage supply should be clean, with very low ripple/noise: provide the suggested bypass
capacitors, in particular if the application device integrates an internal antenna.
Do not apply loads which might exceed the limit for maximum available current from
V_INT
supply.
Check that voltage level of any connected pin does not exceed the relative operating range.
Check
USB_D+
/
USB_D-
signal lines as well as very low capacitance ESD protections if accessible.
Capacitance and series resistance must be limited on each SIM signal to match the SIM specifications.
Insert the suggested capacitors on each SIM signal and low capacitance ESD protections if accessible.
Check UART signals direction, as the TOBY-L2 signal names follow the
ITU-T V.24 Recommendation
Consider providing appropriate low value series damping resistors on SDIO lines to avoid reflections.
Provide accessible test points directly connected to the following pins of the TOBY-L2 series modules:
V_INT
,
PWR_ON
and
RESET_N
for diagnostic purpose.
Provide accessible test points directly connected to all the UART pins of the TOBY-L2 series modules
(
TXD
,
RXD
,
RTS
,
CTS
,
DTR
,
DSR
,
DCD
,
RI
) for diagnostic purpose, in particular providing a 0
series
jumper on each line to detach each UART pin of the module from the DTE application processor.
If the USB is not used, provide accessible test points directly connected to the
USB_D+
and
USB_D-
pins
Provide proper precautions for EMC / ESD immunity as required on the application board.
Do not apply voltage to any generic digital interface pin of TOBY-L2 series modules before the switch-on
of the generic digital interface supply source (
V_INT
).
All unused pins can be left unconnected except the
RSVD
pin number 6 of TOBY-L2 series modules,
which must be connected to GND.
