Special Functionality Pins; Power Supply; Power Supply Pins (3 And 4) On The Board-To-Board Connector - FALCOM I56 Hardware Description

I65/I56I HARDWARE DESCRIPTION
modems and DSU/CSU devices generally use DCE connectors. As a general
rule, DTE ports connect to DCE ports via straight through pinned cables. In
other words, a DTE port never connects directly to another DTE port. In a
similar manner, a DCE port never connects directly to another DCE port. The
signalling definitions were written from the perspective of the DTE device;
therefore, a Receive Data signal becomes an input to DTE but an output from
DCE.
The I56/I56i is designed for use as a DCE. Based on the aforementioned
conventions for DCE-DTE connections it communicates with the customer
application (DTE) using the following signals:
I56/I56i (DCE)
TX_0
RX_0
RTS_0
CTS_0
DTR_0
DSR_0
DCD_0
RING_0
Table 8: Definitions between DTE and DCE ports.

5.4 Special functionality pins

5.4.1 Power supply

The power supply for the GSM/GPRS engine of the I56/I56i module has to be
a single voltage source of V
sufficient current in a transmit burst which typically rises to 1.6 A.
All the key functions for supplying power to the device are handled by an
ASIC power supply. The ASIC0 provides the following features:
Stabilizes the supply voltages for the GSM base band using low drop
linear voltage regulators.
Controls the module's power up and power down procedures.
A watchdog logic implemented in the base band processor periodically
sends signals to the ASIC, allowing it to maintain the supply voltage for
all digital I56/I56i components. Whenever the watchdog pulses fail to
arrive constantly, the module is turned off.

5.4.2 Power supply pins (3 and 4) on the board-to-board connector

Two VC5 pins of the board-to-board connector are dedicated to connect the
supply voltage, five GND pins are recommended for grounding.
This confidential document is the property of FALCOM GmbH and may not be copied or circulated without permission.
to
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= 4.5 ... 5,5 V. It must be able to provide
VC5+
VERSION 1.00
Application (DTE)
TXD
RXD
RTS
CTS
DTR
DSR
DCD
RING
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