Sony Ericsson GM28, Integrator'S Manual

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GM28 INTEGRATOR’S MANUAL
28
LZT 123 7468 R1A
2. Electrical Description
All electrical connections to the GM28 are designed to meet the
standard air (4kV) and contact (8kV) discharge ESD tests, of
EN 301 489-1.
The modem uses the following industry standard connectors:
• RJ11 6-way (power connector)
• RJ9 4-way (handset connector)
• SIM card reader
• FME male coaxial jack (antenna connector)
• Sub-D socket, 9 pin (RS232 serial port)
2.1 Power Connector
An RJ11 6-way connector, as shown and described below, serves as a
means of supplying and controlling d.c. power to the modem.
The supply voltage, VCC, required by the modem is in the range 5V -
32V d.c. Application of the supply voltage does not switch the modem
on. To do so an additional active-high control signal, TO_IN, must be
applied for > 0.2s.
A second active-high control signal, HR_IN, can be used to switch the
modem off when applied for 1 - 2 seconds, or can be used to perform a
hardware reset when applied for > 3.5s.
TO_IN and HR_IN are referenced to GND (pin 6 on the connector).
VCC and GND are reverse polarity and overvoltage protected.
6 5 4 3 2 1
1 VCC
2 n/c 3 HR_IN
4 TO_IN 5 n/c
6 GND