XECOM
(1)
XE3314C
XE3314C
5/2002
Worldwide 33.6 KBPS Modem Module for Embedded Applications
Description
Xecom's XE3314C is a complete, 33.6 Kbps modem in a
single component. Xecom designed the XE3314C for use
throughout North America, Europe and Japan. It includes
user transferrable FCC Part 68 Registration for direct
connection to telephone lines in the United States and is
compliant with CTR21, the standard for pan-European
telecommunications approval.
The XE3314C is a complete modem packaged in a
compact module. The XE3314C includes all required
modem circuits including the DAA. XE3314C users do
not need to add RAM, ROM, Crystals, low distortion
transformer, or switches to complete the modem design.
The user only needs to provide the TTL level, serial
interface and the telephone line connection.
The XE3314C is pin compatible with Xecom's
XE1414C, modem. This family of modems permits a
simple upgrade path from 14,400 bps to 33,600 bps for
international embedded modem applications.
Features
Meets telecom requirements for Europe, North
America, and Japan: Includes User Transferrable FCC
Part 68 Registration and CTR21 compliance
Small Size: 2.75 inches by 1.38 inches by 0.42 inches;
Modem Protocols for data transfer from 33.6 KBPS
down to 300 BPS: V.34bis, V.34, V.32bis, V.32,
V.22bis, V.22, V.21, Bell 212A and 103;
Modem Control and Configuration via AT Commands
Fax Protocols: V.17, V.29, V.27ter, and V.21 channel 2
Error Correction; V.42, MNP2-4 and MNP10
Data Compression; V.42bis and MNP5 provides a
maximum effective data rate of 133,400 bps.
Non-Volatile Memory included for storing telephone
numbers and modem configuration.
Standard operating temperature range 0C to 70C.
Extended operating temperature range of -40C to +85C
is available.
Block Diagram
Modem
Controller
ROM
NVRAM
Analog
Front
End
DAA
/DTR
/RTS
/CTS
/DSR
TXD
RXD
/DCD
Serial I/O
RESET
AR
LCS
OH
AMP
L1
L2
Tip
Ring
Auxiliary I/O
XECOM
(2)
XE3314C
XE3314C PIN CONFIGURATION
NC
AR
RXD
NC
NC
NC
NC
NC
/DTR
LCS
/CTS
NC
TXD
/RTS
NC
/RI
TIP
RING
VCC
/DSR
/DCD
NC
RESET
NC
NC
NC
NC
NC
OH
NC
L2
L1
AMP
GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
18
20
40
39
38
37
36
35
34
33
32
31
30
29
28
27
22
21
XE3314C Mechanical Specifications
Pins = 0.025 inch square pin; All pins tin-plated
A
2.74
2.760
69.60
70.10
B
1.370
1.390
34.80
35.31
C
0.420
0.430
10.67
10.92
D
1.190
1.210
30.23 30.73
E
1.890
1.910
48.01
48.51
F
0.125
0.200
3.18
5.08
G
0.080
0.100
2.03
2.54
H
0.415
0.435
10.54
11.05
J
0.090
0.110
2.29
2.79
K
0.020
0.025
0.51
0.64
INCHES
METRIC(MM)
PIN
MIN
MAX
MIN
MAX
Denotes Pin 1
A
B
K
F
H
E
J
H
C
D
G
G
XECOM
(3)
XE3314C
PIN NAME
DESCRIPTION
XE3314C PIN DESCRIPTIONS
1
NC
No Internal Connection
2
AR
Auxiliary Data/Voice Relay, Active High Output, TTL/CMOS. The AR signal goes high when ever the mo-
dem is in the on-hook state. It can be connected to an external relay to switch control of the telephone line
between the modem and an auxiliary handset when.
3
RXD
Received Data, Output, TTL. Serial data output to the host. A logic "High" on RXD represents a "mark"
and a logic "Low" represents a "space".
4-8
NC
No Internal Connection
9
\DTR
Data Terminal Ready, Input, active Low, TTL. The "AT&D" command sets the function of \DTR. The de-
fault, AT&D2, requires the host to assert \DTR to permit a modem link. The modem drops the call in
progress if \DTR is revoked and will not connect until \DTR is reasserted.
10
LCS
Loop Current Sense, input, active High, TTL/CMOS. LCS provides an input to the modem from an ex-
ternal loop current sensor. The Loop Current Sensor may be required for some applications in which the
modem shares a telephone line with a telephone handset.
11
\CTS
Clear to Send, Output, active Low, TTL/CMOS. \CTS provides the flow control output from the modem
when hardware flow control is selected. The modem revokes \CTS when the modem's input buffer is
full. The modem reasserts \CTS when the buffer can accept more data without a buffer overflow.
12
NC
No Internal Connection
13
TXD
Transmit Data, Input, TTL. Serial data input from the host. A logic "High" represents a "mark" and a
Low represents a "space", TTL.
14
\RTS
Request to Send, input, active Low, TTL. The XE3314C uses \RTS for hardware flow control. When
\RTS is revoked; hardware flow control is activated, and the modem will not place data on RXD.
15
NC
No Internal Connection
16
\RI
Ring Indicator, Output, active Low, TTL. When low indicates the modem is receiving a ring signal.
18
TIP
Tip connection to the phone line (RJ11 pin 3) from the internal DAA. The XE3314C is not sensitive to
the battery voltage polarity across Tip and Ring.
20
RING
Ring connection to the phone line (RJ11 pin 4) from the internal DAA.
21
GND
Ground (0 volts)
22
AMP
Audio Output function is set by L & M commands and the value in register S22. This output can drive a
minimum load of 300 ohms.
27-28
L1, L2
L1 and L2 provide the control the performance of the loop current holding circuit. When a jumper is applied
between L1 and L2, the CTR21 current limiting circuit is active and DC loop current is limited to 60
milliamps. When no jumper is provided, a full 100 milliamps of loop current is supported.
30
OH
Off-Hook, Output, active High. OH indicates the modem's hookswitch relay is closed. Hookswitch closure
connects the modem to the telephone line.
31-35
N/C
No Internal Connection
36
RESET
Hardware reset pin, Input, active High, TTL. A high on Pin 36 initiates a hardware reset. An external reset
is not required or recommended. The Reset pulse must be held a minimum of 100 milliseconds.
37
N/C
No Internal Connection
XECOM
(4)
XE3314C
Parameter
Min
Typ
Max
Units
Comments
XE3314C ELECTRICAL SPECIFICATIONS
VCC
4.75
5.25
Volts
ICC
140
160
180
ma
On Line
40
ma
Sleep Mode
Ring Voltage Detected
38
150
RMS
Type B Ringer
Ring Frequency Detected
15.3
68
Hz
Type B Ringer
Telephone Loop Current
20
100
ma
Off-Hook
Data Transmit level
-11.0
-10.0
-9.0
dBm
DTMF Transmit Level
-2.5
0
dBm
Avg over 3 second interval
SUPPLY VOLTAGE - Vcc
+6.5 Volts
DC INPUT VOLTAGE
-0.6 Volts to +6.5 Volts
STORAGE TEMPERATURE RANGE
-25 C TO +85 C
LEAD TEMPERATURE (Soldering, 2 sec per wave)
260 C
OPERATING TEMPERATURE RANGE
1
0 TO 70 C
*Exceeding these values may result in permanent damage to the device.
1
Extended Operating Temperature (-40
to +85
C) available. Order XE3314C-ITR
XE3314C ABSOLUTE MAXIMUM RATINGS
PIN NAME
DESCRIPTION
XE3314C PIN DESCRIPTIONS
38
\DCD
Data Carrier Detect, Output Active Low, TTL/CMOS. The &C command sets the function of \DCD. In the
default state \DCD activates when a valid carrier is detected.
39
\DSR
Data Set Ready, Output, active Low, TTL/CMOS. &S sets the \DSR function. In the default condition, AT&S0,
\DSR is forced true.
40
Vcc
+5 Volts
XECOM
(5)
XE3314C
XE3314C Typical Connection Diagram
Notes: 1) RJ11 Pin assignments reflect a 6-pin connector. Tip and Ring are always the center pins of the RJ11
Jack.
2) CTR21 requires the modem to be able to dissapate over two Watts in come applications where the integral
current limiting circuit is activated. The XE3314C requires a heat sink to be added to dissapte this addi-
tional power.
Recommended Parts
Reference Designation
Description
Recommended Part Number
FB1, FB2
Ferrite Beads
TDK ACB2012L-120-X
C1, C2
Capacitors
Panasonic ECKDRS471, 470 pfd, 2600 Volts
J1, J2
RJ11 Jack
Stewart SS6446NF
XE3314C
/RXD
/TXD
/DTR
/RTS
/CTS
/DSR
/DCD
/RI
16C550
UART
LM386
.05 ufd
10 ohms
250 ufd
8 ohm,
.5 W
speaker
.2 ufd
50K
AMP
GND
Ring
Tip
L1
L2
FB1
FB2
C1
C2
J1
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