User's Manual

DRAFT
4: VAM-CM interfaces
Signal Description Min Max Unit
PWR on/off Power on/off control 0 4,5 V
Supply Supply voltage 2,1 4,5 V
Vio IO system voltage -0,5 5,5 V
Table 1. Absolute maximum ratings
4.2: VAM Control interface description
The VAM control interface is a combination of digital and analog baseband interfaces dedicated to
control the VAM-CM. The Interface also includes other user interface related signals like USIM and
audio. The VAM control interface is a Harwin M50-360-25 42 male type pin header connector. The
Connector is located so trace lengths are short enough to enable correct functionality of all
interfaces.
The VAM-CM processor (DM3725) uses 1,8V I/O system. In order to protect the processor, digital
interfaces are connected via level shifters. A VAM terminal can determine the interface voltage level
by applying the desired V_io voltage to the VAM control interface connector. Voltage requirements
for logic levels are shown in Table 2 . For more details, see Power Supply interface description
on page 16.
Description Min Max Unit
V
IH
High level input voltage V
IO
– 0,4 V
IO
V
V
IL
Low level input voltage 0 0,15 V
V
OH
High level output voltage V
IO
* 0,67 V
IO
V
V
OL
Low level output voltage V
IO
<3V 0 0,4 V
V
IO
>=3V 0,55 V
Table 2. Logic levels for Level Shifter
Figure 6. VAM-Control interface connector
Figure 6 shows the connector used for VAM control interface and pin arrangement. Following
chapters describe the sub interfaces and their location in connectors.
4.2.1:System USB description
The system USB interface is a dedicated interface providing access to the VAM-CM. This interface is
targeted for firmware updates and direct VAM-CM controls. The system USB connector shall be
routed out from VAM terminal for direct access. The system USB interface can also be used for VAM-
CM control when USB mode is selected with VAM Boot selector during VAM-CM power-on. The VAM
can put CM in low power mode by sending USB suspend command and wakeup is initiated by
sending resume command. Refer to VAM-CM USB interface PM Handling on page 20 for CM
low power (Sleep state) handling.
System USB interface signals are located in VAM Control interface as described in Table 3 .
12:GSPS Core Module 2.0 VAM-CM HW Description
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