Specifications
PART 2 – Cellular SocketModems Chapter 5 – SocketModem iCell HSPA
Multi-Tech Systems, Inc. Universal Socket Hardware Guide for Developers (S000342P) 91
Pin-Out Specifications
Pin Signal Name
Logic Level
Voltage*
I/O Description
J15** GPS SDI 3.3 v LVTTL I GPS Data In
J16 GPS SDO 3.3 v LVTTL O GPS Data Out
J17 GPS PPS 3.3 v LVTTL O GPS Pulse Per Second
J24 –RESET 3.3 – 5.0 I Device reset (active low)
J25 USB VBUS 3.3 – 5.0 I USB power supply input
J26 GND GND GND Ground
J27 USB DP 3.3 I/O USB data
J28 USB DM 3.3 I/O USB data
J33 –RTS 5.0 I Request to send (active low)
J34 –RXD 5.0 O Received data (active low)
J35 –TXD 5.0 I Transmitted data (active low)
J36 –RI 5.0 O Ring indicator (active low)
J37 –DSR 5.0 O Data set ready (active low)
J38 –CTS 5.0 O Clear to send (active low)
J39 –DCD 5.0 O Data carrier detect (active low)
J40 –DTR 5.0 I Data terminal ready (active low)
J41 GND GND GND Ground
J48
GPIO0
3.3
I/O
User configurable general purpose I/O
J49 GPIO1 3.3 I/O User configurable general purpose I/O
J50 GPIO2 3.3 I/O User configurable general purpose I/O
J51 GPIO3 3.3 I/O User configurable general purpose I/O
J58 –LED LINK 3.3 O Link status (active low, can sink up to 150mA)
J61 VCC 5.0 PWR DC input power
J63 GND GND GND Ground
*Note: A hyphen (-) indicates a range of acceptable logic levels.
**Note: If J15 is to be unused, it is suggested that 100k pull-up resistor be used. Other pins can be No Connects.
Serial Model Pin Out
For Products: MTSMC-H4-IP, MTSMC-H4-GP
Pins Available With Current PCB: 24, 26, 33-41, 61, 63
USB + Serial + GPIO + GPS Data Pin Out
For Products: MTSMC-H4-MI-IP, MTSMC-H4-MI-GP
Pins Available With Current PCB: 24-28, 33-41, 48-51, 58, 61, 63
Pins to Be Added to the Next PCB Revision: 22-23, 42-43 and new GPS data pins 15-17
Design Consideration – Very Important Note
The current revision of the PCB will not accommodate the following pins:
22-23, 42-43 and the new GPS data pins 15-17.
While these pins are not present at this time, they will be present on the
next hardware release.
You, as the developer, must take these new pins into account in your
product design even if you have no plans for using them.