XE2420 March 2002 2400 BPS Surface-Mountable Integrated Sealed-Hybrid Modem Description Features Xecom’s XE2420 provides a complete 2400 BPS modem into an inexpensive miniature, surface-mount package. Xecom’s new HyPLCC™ package (Hybrid PLCC) makes it possible to meet the conflicting goals of small size, low cost and surface-mountability. The XE2420 targets remote monitoring applications in industrial, commercial and residential locations * Small Size: The HyPLCC™ measures less than 1 inch by 1inch square and 0.290 inches thick As a complete modem, the XE2420 includes not only all modem circuitry but also user transferrable FCC Part 68 Registration and UL60950 recognition. This allows the XE2420 to be safely integrated into your embedded application. * Modem Control and Configuration via industry standard AT Commands. * Surface-mountabile: The HyPLCC™ package is equivalent to a 68-Pin PLCC device. * Data transfer at 2400, 1200 and 300 BPS using V.22bis, V.22, V.23, V.21, Bell 202, Bell 212A, and Bell 103 Protocols * Supports external shared line features permitting unobtrusive sharing of a local telephone line. * Complete integrated DAA includes, Ring Detect, Loop Current Holding Circuit, Hook Switch. Metalic Surge Protection, and Telephone Line Transformer Xecom’s new HyPLCC™ package infuses the XE2420 with both its small size and surface mountability. The HyPLCC package allows complex hybrid circuits to fit the 68-Pin PLCC footprint. The HyPLCC™ package provides a completely sealed enviroment protecting the XE2420 during assembly and board cleaning operations. * User Transferrable FCC Part 68 Registration * UL60950 Recognition * Low Power operation, 330 milliWatt; Power down operation less than 1 microWatt XE2420 BLOCK DIAGRAM XECOM (1) XE2420 XE2420 Mechanical Specifications b c a d i i g (TOP) f c e e .050” 45O Dimension a b c d e f g i(radius) XECOM Min 0.280 0.985 0.950 0.910 0.045 0.695 0.395 0.015 Inches Typ 0.285 0.990 0.955 0.920 0.050 0.700 0.400 0.020 i Max 0.290 0.995 0.960 0.930 0.055 0.705 0.405 0.025 (2) Millimeters Min Typ 7.11 7.24 25.02 25.15 24.13 24.26 23.11 23.37 1.15 1.27 17.65 17.78 10.03 10.16 0.13 0.25 Max 7.37 25.27 24.38 23.62 1.40 17.91 10.29 0.38 XE2420 XE2420 Pin Configuration /DCD 1 /CTS 2 RESET 3 /DSR 4 24 RING /RTS 5 23 N/C /DTR 6 22 TIP /RXD 7 21 N/C TOP /TXD 8 20 N/C /RI 9 19 HI3 GND 10 18 HI1 N/C 11 17 CD EECL 12 16 HI2 EEDT 13 Vcc 14 Vui 15 Pin Descriptions PIN NAME 1 /DCD /DCD is an active low output from the modem. The AT&C command controls when the XE2420 asserts /DCD. 2 /CTS /CTS is an active low output from the modem. The modem asserts /CTS to indicate that it can accept data from the terminal equipment on /TXD. 3 RESET RESET is an active high input which intiates a modem hardware reset. RESET must be active for a minimum of 100 milliseconds for a proper modem reset sequence. No external reset is required; if none is used the RESET signal should be left open. 4 /DSR /DSR is an active low output from the modem. The AT&S command controls when the XE2420 asserts /DSR. 5 /RTS /RTS is an active low input to the modem. /RTS indicates to the modem that the host has data to send. 6 /DTR /DTR is an active low input to the modem. The AT&D command determines how the modem will interpret activity on /DTR. 7 /RXD /RXD provides the path for received data and modem responses to be sent from the modem to the host terminal equipment. XECOM DESCRIPTION (3) XE2420 XE2420 Pin Descriptions (continued) PIN NAME 8 /TXD /TXD provides the path for transmitted data and modem commands to be passed from the host terminal equipment to the modem. 9 /RI The /RI signal reports on the presence of an incoming ring signal. When a ring occurs across Tip and Ring, the /RI output toggles at the ring frequency. The /RI output is powered by Vui and therefore operates even when VCC is removed from the modem. 10 Ground 11 N/C 12 EECL EECL provides the clock to the optional external non-volatile memory. The XE2420 requires a serial 8 by 256 Byte EEPROM for telephone number storage. If the non-volatile memory is not used, EECL should remain unconnected. 13 EEDT EEDT provides the serial data connection for the optional, external non-volatile memory. The XE2420 requires a serial 8 by 256 Byte EEPROM for telephone number storage. If the nonvolatile memory is not used, EEDT should remain unconnected. 14 VCC VCC provides 5 volt power to the modem. The RI output is not powered by VCC but by Vui. 15 Vui Vui provides uninterrupted power to the XE2420 ring detect circuit. Placing 5 volt power on Vui insures that the /RI ouput will operate when VCC is removed from the modem. 16 HI2 HI2 is one of the four hardware hooks for connecting shared line features to the XE2420. HI2 interfaces to the 911 Interrupt circuit. This circuit detects changes in the loop current when an extension handset is lifted as when making an emergency call. The system host should immediately abort the modem connection to permit the user to complete their call. See the Application Note on Page 10 of this data sheet to see how these line monitoring circuits interface with the XE2420. 17 CD CD provides another of the four hardware hooks for connecting shared line features to the XE2420. CD interfaces to the Connect Dectect circuit. Connect Detect allows the system host to check the status of the telephone line before going off-hook to initiate a call. If the phone line is in use,the host can delay its call until the telephone line is free. See the Application Note on Page 10 of this data sheet to see how these line monitoring circuits interface with the XE2420. 18 HI1 HI1 is one of the four hardware hooks for connecting shared line features to the XE2420. HI1 interfaces to the 911 Interrupt circuit. This circuit detects changes in the loop current when an extension handset is lifted as when making an emergency call. The system host should immediately abort the modem connection to permit the user to complete their call. See the Application Note on Page 9 of this data sheet to see how these line monitoring circuits interface with the XE2420. XECOM DESCRIPTION Ground provides the reference voltage for all host interface signals. No internal connection (4) XE2420 XE2420 Pin Descriptions (continued) PIN NAME DESCRIPTION 19 HI3 HI3 is one of the four hardware hooks for connecting shared line features to the XE2420. HI3 interfaces to the 911 Interrupt circuit. This circuit detects changes in the loop current when an extension handset is lifted as when making an emergency call. The system host should immediately abort the modem connection to permit the user to complete their call. See the Application Note on Page 10 of this data sheet to see how these line monitoring circuits interface with the XE2420. 20 N/C No internal connection, To prevent damage in case of voltage surges on the telephone line, we recommend that nothing be connected to this pin. 21 N/C No internal connection, To prevent damage in case of voltage surges on the telephone line, we recommend that nothing be connected to this pin. 22 Tip The Ring and Tip signals provide modem the connection to the telephone line. FCC Part 68 Rules require a 1500 volt isolation barrier between the telephone line and all other circuits. This isolation must be preserved throughout the system. The telephone company places a DC “Battery” voltage across Tip and Ring on all public switched telephone lines. The XE2420 will operate regardless of the polarity of this “Battery” voltage. The “Battery” voltage drives up to 100 milliamps of DC loop current. UL60950 requires minimum creepage and clearances distances be maintained between the Tip and Ring traces and all other circuits. Clearance is the shortest distance between conductive circuits; creepage is the distance between conductive surfaces along the surface 23 N/C No internal connection, To prevent damage in case of voltage surges on the telephone line, we recommend that nothing be connected to this pin. 24 Ring The Ring and Tip signals provide modem the connection to the telephone line. FCC Part 68 Rules require a 1500 volt isolation barrier between the telephone line and all other circuits. This isolation must be preserved throughout the system. The telephone company places a DC “Battery” voltage across Tip and Ring on all public switched telephone lines. The XE2420 will operate regardless of the polarity of this “Battery” voltage. The “Battery” voltage drives up to 100 milliamps of DC loop current. UL60950 requires minimum creepage and clearances distances be maintained between the Tip and Ring traces and all other circuits. Clearance is the shortest distance between conductive circuits; creepage is the distance between conductive surfaces along the surface. XECOM (5) XE2420 XE2420 Soldering Instructions The XE2420 is subject to damage if over-exposed to heat during solder reflow operations. Following the soldering instructions below will ensure that the process of soldering the module to the board does not damage the modem. The XE2420 must not be exposed to direct Infrared (IR) heating. If your process includes direct IR heating, you must shield the XE2420 from the infrared rays. Maximum Temperature Maximum Time at 220O C Maximum Time above Eutectic (180O C) Maximum Preheat Dwell Time 220O C 20 Seconds 90 Seconds 180 Seconds Maximum Recommended Solder Temperature Profile 220O C 180O C 150O C -20 sec--------------------------------180 sec max --------------------- max ----- 90 sec max ----- XECOM (6) XE2420 XE2420 Electrical Specifications Parameter Min VCC 4.75 ICC 60 ICC Typ Max Units 5.25 Volts 72 ma On Line ma idle 66 25 Vui 4.75 5.25 Volts 1 µa 38 150 RMS Type B Ringer 15.3 68 Hz Type B Ringer Iui Ring Voltage Detected Ring Frequency Detected Connect Detect Sensitivity 20 Handset Interrupt Detection Telephone Loop Current 1.0 10 Line Impedance Data Transmit level 40 -12 No Ring Signal Present Volts DC Battery Voltage level detected by circuit shown on Page 10 Volts DC Change in Battery Voltage detected by circuit shown on Page 10 100 600 DTMF Transmit Level Voh Comments ma Ohms -10 -9 dBm -2.5 0 dBm 2.4 Avg over 3 second interval Volts Vol 0.4 Volts Vih 2.0 VCC+0.3 Volts Vil -0.3 0.8 Volts XE2420 ABSOLUTE MAXIMUM RATINGS -25O C to +85O C Storage Temperature Operating Temperature Range1 0O C to +70O C Maximum Time Above Eutectic (183O C) 90 seconds Preheat Dwell Time 1 120 to 180 seconds The XE2420 can be ordered with an Operating Temperature of -40O C to +85O C at extra cost. Order XE2420-ITR or to specify Industrial Temperature Range (ITR). XECOM (7) XE2420 XE2420 Typical Application Schematic NM24C04 +5 Volts 20K A0 VCC A1 WP XE2420 A2 SCL Reset VSS SDA EECL EEDT 16C550 UART /TXD /TXD /RXD /RXD /RTS /RTS RJ11 FB1 RING C1 /RI /RI /DSR /DSR /DCD /DCD /CTS /CTS /DTR /DTR +5 Volts Battery FB2 TIP C2 Vcc Vui Gnd Notes: 1 FB1 and FB2 are ferrite beads which may be required for EMI filtering in your system. Without these components you may experience unintended radiation when the telephone cable is attached to your system. We recommend selecting components such as the TDK ACB2012L-120 which provide a minimum of 100 ohms of impedence at frequencies above 100 MHz. 2. C1 and C2 are high-voltage capacitors which may be required for EMI filtering in your system. Without these components you may experience unintended radiation when the telephone cable is attached to your system. We recommend selecting components such as the Panasonic ECKDRS471. This 470 pfd, 3000 volt capacitor will direct the high frequency harmonics to the system ground. These capacitors must be rated at a minimum of 1500 volts to maintain the isolation required by FCC Part 68 Rules. 3. The Battery applied to Vui allows the XE2420’s Ring Indicate output to remain active even when the modem itself is powered down. If this power-down mode is not required for your application, Vui should be tied to VCC. 4. The EEPROM, NM24C04, provides for non-volatile storage of telephone numbers using the AT&Z command. The EEPROM must be programmed using the Diplomat™ Utility from Zilog Inc. Diplomat™ is a trademark of Zilog Inc. XECOM (8) XE2420 Application Note: Using a 68-Pin PLCC Socket The XE2420 can be inserted into a socket for a 68-pin PLCC device. The HyPLCC package uses only 24 pins; 15 on one side and 9 on the opposite side. Allignment within the socket is critical for all pins of the XE2420 to make contact with the appropriate pins of the PLCC socket. The drawing below illustrates how the XE2420 can be inserted into the 68-pin PLCC socket. 60 XE2420 61 1 44 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 43 24 23 22 21 20 19 18 17 16 9 27 10 XECOM 26 (9) XE2420 Application Note: XE2420 Shared Line Feature For applications where the XE2420 shares a telephone line with a telephone handset, Xecom has provided four hardware hooks for connecting two monitoring circuits. These circuits monitor the status of the telephone line to prevent the modem from interfering with a voice call. The Connect Detection Circuit monitors the telephone loop voltage when the modem is not in use. This allows the system host to check the status of the telephone line before initiating a call. The ConDetect signal will be be high when the phone line is available but goes low to indicate that the telephone line is in use. The Handset Interupt or 911 Interrupt circuit monitors loop current while the modem is in the off-hook state. This circuit detects the change in loop current which occurs when a handset on the shared telephone line is lifted. The HSInterrupt output will go low momentarily if the handset is lifted during data communications. The system host can then immediately abort the modem connection and permit the user to complete their call. Parts List for Shared Line Feature Application Note Reference Designation Qty Description Reference Designation Qty Description C1, C2 2 Cap. 470 pfd 2600V R7 1 Resistor, 56K 5% C3 1 Cap. 10 ufd 20% 16V R8 1 Resistor, 33K 5% C4 1 Cap. 1 Ufd, 20% 10V R9 1 Resistor, 402K 5% F1, F2 2 PTC, TR600-150 R10 1 Resistor, 1M 5% FB1, FB2 2 Ferrite, ACB2012L-120 R11 1 Resistor, 1.5K 5% Q1 1 Trans. FMMT3904 R12 1 Resistor, 20K 5% R1, R2 2 Resistor, 10M 5% R13 1 Resistor, 100K 5% R3, R5, R6 3 Resistor, 200K 1% U1, U2 2 OP Amp, TLC271CD R4 1 Resistor, 280K 1% U3 1 Opto-coupler, PS2705-1 XECOM (10) XE2420 XE2420 AT Commands The XE2420 uses "AT" commands for configuration and control. This section describes use of the AT command format and lists the AT commands, Registers and Result codes. XE2420 "AT" commands have two operational modes; Command Mode and Data Mode. Command Buffer - No more than 36 characters, including the AT prefix, may be loaded into the command buffer. If the command buffer overflows, the modem issues an "ERROR" result code and commands are not executed. Data Mode: The XE2420 enters data mode after it connects with a remote modem and issues the appropriate result code. In the Data Mode the modem sends all data presented on Transmit Data (/TXD) to the remote modem and puts data from the remote modem onto Received Data (/RXD). When the modem exits data mode, it issues a "NO CARRIER" result code. Command Line Editing - The backspace edits a command line before it is executed. The backspace key, (Control and H simultaneously on some systems), erases the previous character in the command line. Register S5 allows the user to select a character other than a backspace to edit the command line. Command Mode: The XE2420 enters command mode on power-up, reset, a lost connection, or receipt of the escape code. In command mode the modem accepts commands from the host on transmit data. Appropriate result codes are returned on received data. Command Line Format Command lines issued to the modem follow a strict format. Each command begins with the prefix AT. The command line is stored in the command buffer and executed upon receipt of a carriage return. Until executed, the command line can be edited with the backspace key. Command Prefix - Each command, except the A/ command, begins with the AT prefix. The "A" and "T" may be either both upper case or both lower case but cannot be of different cases. The prefix identifies the speed and parity of the commands sent to the modem by the host. Speed is determined by measuring the width of the incoming bits. Parity is determined by comparing the parity bit of the "A" and the "T." Command Line - Commands may be strung together in a single command line of up to 36 characters. Commands are executed in the sequence they appear. Spaces may be inserted into the command line but do not fill space in the command buffer. A carriage return terminates the command line and causes the commands to be executed. Register S3 allows the user to select a character other than a carriage return to terminate the command line. XECOM Re-Execute Last Command - The A/ command causes the modem to re-execute the last command line. This is the only command which does not require the "AT" prefix. Omitted Parameters - Most commands include a parameter which determines how the functions will be set. When the command parameter is omitted from the command string, it is assumed to be a 0. Escape Characters - A 3 character escape sequence maybe entered while in data mode to switch the modem into command mode while on line. The escape character, set by Register S2, must be entered 3 times in succession to execute the escape. An AT command must then be enterred within the period defined by S12 to enter the command mode. The default escape sequence is "+++." Result Codes - The modem issues a result code after each action. Result codes may be provided as full words, one or two digit numeric codes, or may be disabled all together. Each result code ends with a carriage return when numeric result codes are chosen. When full word result codes are chosen, a Line Feed and Carriage Return preceed and follow each result code. (11) XE2420 XE2420 AT Commands An asterisk indicates the factory default A - Answer Command - Xn - Result Code Set n=0 n=1 n=2 n=3 n=4 Bn - Select Communications Standard n=0 Selects CCITT standards n=1 Selects Bell standards* n=2 Selects V.23/Bell 202 (see S37) D - Dial Command 0-9, A-D, #, * = Dialing Digits P = Pulse dial T = Tone dial R = Connect as an answering modem W = Wait for dial tone , = Pause for the duration of S8 @ = Wait for silence ! = Switch hook flash ; = Return to the command state S=n = Dial Stored Number n En - Command Echo n=0 Do not echo commands n=1 Enable command echo* &Cn - DCD Operation n=0 DCD is forced active* n=1 DCD indicates a valid carrier signal &Dn - DTR n=0 DTR is ignored* n=1 When the modem is on-line DTR off switches it to the command mode and issues OK response. n=2 Modem disconnects if the host revokes DTR. n=3 The modem performs a soft reset when DTR is revoked. &F - Reset Factory Defaults &Gn - Guard Timer n=0 None * n=1 550 Hz Guard Timer n=2 1800 Hz Guard Timer Hn - Switch Hook Control n=0 Switch hook relay opens n=1 Switch hook relay closes In - Modem Identification Mn - Speaker Activity n=0 n=1 n=2 n=3 Speaker off Speaker on until carrier received* Speaker remains on Speaker on after dialing until carrier is detected. On - On Line n=0 Return On Line with no retrain* n=1 Initiate retrain while returning On line. Qn - Responses Responses 0-4 Responses 0-5 & 10 Responses 0-6 & 10 Responses 0-5, 7 & 10 Responses 0-7 & 10* &Sn - Data Set Ready n=0 Data Set Ready Forced Active * n=1 Data Set Ready on at Start of Modem handshake &Z=x - Store dialing string x %En - Automatic Retrain n=0 Automatic Retrain Disabled n=1 Automatically retrain on poor signal quality * \Nn - Data Buffering n=0 Data Bufferred n=1 Direct Mode no data buffering * \Qn - Flow Control n=0 n=1 n=2 n=3 n=4 n=0 Send responses * n=1 No Responses Sr? - Interrogate Register Sr=n - Set Register Value - Flow Control Disabled XON/XOFF Flow Control CTS Flow Control RTS/CTS Flow Control * DCE to DTE XON/XOFF Flow Control Vn - Result Codes n=0 n=1 Numeric Result Codes English Word Result Codes* XECOM (12) XE2420 XE2420 Modem Registers S0 Answer on nth Ring: S0 sets the modem to automatically answer on the nth ring. Setting S0 to 0 disables automatic answer. Range: 0 to 255 Units Rings Default 0 S7 Wait for Carrier after Dialing: S7 determines how long the modem waits for a valid carrier signal after dialing is completed. Range: 1 to 255 Units Seconds Default 30 S1 Ring Count: S1 is a read-only register showing the number of rings detected. If a ring is not detected within 8 seconds, S1 is reset to zero. Range: 0 to 255 Units Rings Default 0 S8 Comma Pause Time: S8 defines the duration of the pause initiated by a comma in the dialing string. The pause is generally used when waiting for a second dial tone. Range: 1 to 255 Units Seconds Default 2 S2 Escape Character: S2 determines the ASCII escape character. Values of 0-127 select valid ASCII escape characters; values from 128 to 255 disable the escape sequence. Range: 0 to 255 Units ASCII Character Default 43 (+) S9 Carrier Detect Response Time: S9 establishes the length of time the remote modem's carrier must be present to be recognized as valid. Range: 1 to 255 Units 0.1 Seconds Default 6 S10 S3 Line Termination Character: S3 determines the ASCII character which will terminate commands and modem responses. Range: 0 to 127 Units ASCII Character Default 13 (Carriage Return) Carrier Off Disconnect Delay: S10 selects how long carrier must be lost before the modem disconnects. Note: If S10 is smaller than the value of S9 or S10 is set to 255, the modem will not automatically disconnect on loss of carrier. Range: 1 to 255 Units 0.1 Seconds Default 14 S4 Line Feed Character: S4 sets the ASCII character to act as a line feed character in modem responses. Range: 0 to 127 Units ASCII Character Default 10 (Line Feed) S5 S6 Backspace Character: S5 defines the ASCII character used as a backspace to edit the command line. Range: 0 to 127 Units ASCII Character Default 8 (Back Space) S11 Tone Dialing Speed: S11 sets the duration and spacing of the dialing tones. S11 does not affect the pulse dialing rate. Range: 50 to 255 Units 1 Millisecond Default 95 S12 Escape Code Guard Timer: S12 sets the escape sequence guard timer. If characters are received before or after the escape sequence, within the guard timer, the modem aborts the escape attempt and remains in data mode. Range: 0 to 255 Units 0.02 Seconds Default 50 Dial Tone Wait Time: S6 determines how long the modem waits for dial tone before dialing begins. The Dial Tone Wait Time cannot be set to less than two seconds. Range: 2 to 255 Units Seconds Default 2 XECOM (13) XE2420 XE2420 Modem Registers continued S28 S29 Inactivity Timer: S28 determines how long the modem wil remain on line with not data flowing. A 0 in this register disables the inactivity time out. Range: 0-255 Units Minutes Default 0 S37 Maximum Line Data Rate: S37 sets the maximum line data rate or modulation technique that the XE2420 will support for any connection. Register Value Hook Flash Time: S29 determines the the amount of time the modem will go on-hook when a hook switch flash is called for. Range: 0-255 Units 0.02 Seconds Default 25 Communications Supported 0 Maximum Data Rate determined by the autobaud function of the AT Command 1 3 4 5 Connect using V.23, asymmetrical modem modulation, 1200/75 BPS Connect using Bell 202, asymmetrical modulation, 1200/150 BPS V.21, Bel 103, 300 BPS Reserved V.22, Bell212A 1200 BPS 6 V.22bis 2400 BPS 2 XE2420 Modem Responses Digits Verbose 0 OK 1 CONNECT 300 bps connection 2 RING Ring signal detected 3 NO CARRIER Carrier not detected/lost 4 ERROR Error in command line 5 CONNECT 1200 1200 bps connection 6 NO DIAL TONE No dial tone detected 7 BUSY Busy signal detected 8 NO ANSWER 10 CONNECT 2400 16 CONNECT 1200TX/75RX V.23 Connection transmitting at 1200 BPS 17 CONNECT 75TX/1200RX V.23 Connection transmitting at 75 BPS 18 CONNECT 1200TX/150RX Bell 202 Connection transmitting at 1200 BPS 19 CONNECT 150TX/1200RX Bell 202 Connection transmitting at 150 BPS XECOM Description Successfully executed command line 5 second silence not detected 2400 bps Connection (14) XE2420 FCC Instructions The XE2420 complies with part 68 of the FCC Rules and Regulations. With each device shipped, there is a label which contains, among other information, the FCC Registration Number and Ringer Equivalence Number (REN) for this product. You must, upon request, provide this information to your telephone company. The mounting of this device in the final assembly must be made in such a manner as to preserve the high voltage protection between the TIP/RING Connection and the rest of the system. Typically, this may be accomplished by maintaining a minimum spacing 100 mils between the TIP/RING Traces to the RJ-11C Jack and low voltage portion of the system. No additional circuitry may be attached between TIP/RING and the telephone line connection, unless specifically allowed in the rules. The REN is useful to determine the quantity of devices you may connect to a telephone line and still have all of these devices ring when the number is called. In most, but not all areas, the sum of the RENs of all devices connected to one line should not exceed five (5.0). To be certain of the number of devices you may connect to the line, as determined by the REN, you should contact the local telephone company to determine the maximum REN for you calling area. If your system causes harm to the telephone network, the telephone company may discontinue service temporarily. If possible, they will notify you in advance. If advance notification is not practical, you will be notified as soon as possible. Your telephone company may make changes in its facilities, equipment, operations or procedures that could affect proper functioning of your equipment. If they do, you will be notified in advance to give you an opportunity to maintain uninterrupted telephone service. If you experience trouble with this device, please contact XECOM at (408) 945-6640 for information on obtaining service or repairs. The telephone company may ask you to disconnect this device from the network until the problem has been corrected or until you are sure that the device is not malfunctioning. The device may not be used on coin service lines provided by the telephone company (this does not apply to private coin telephone applications which use standard telephone lines). Connection to party lines is subject to state tariffs. XECOM (15) XE2420 Terms of Sale Devices sold by XECOM are covered by the warranty provisions appearing in its Terms of Sale only. XECOM makes no warranty, express, statutory, implied, or by description regarding the information set forth herein, or regarding the freedom of the described devices from patent infringement. XECOM makes no warranty of merchantability or fitness for any purposes. XECOM reserves the right to discontinue production and change specifications and prices at any time and without notice. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment, are specifically not recommended without additional processing and authorization by XECOM for such application. Xecom assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xecom product. No other circuits, patents, or licenses are implied. Life Support Policy Xecom's products are not authorized for use as Critical Components in Life Support Devices or Systems. Life Support Devices or Systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions provided in the labeling, can be reasonably expected to result in significant injury to the user. A Critical Component is any component of a life support device or system whose failure to perform can be reasonably expected to cause failure of the life support device or system, or to affect its safety or effectiveness. Copyright, Xecom © 2001 While Xecom, Inc. has made every effort to ensure that the information presented here is accurate, Xecom will not be liable for any damages arising from errors or omission of fact. Xecom reserves the right to modify specifications and/or prices without notice. Product mentioned herein are used for identification purposes only and may be trademarks and/or registered trademarks of their respective companies. Xecom Incorporated 374 Turquoise Street, Milpitas, CA 95035 Ph:408-945-6640 Fax:408-942-1346 E-Mail: [email protected] XECOM (16) XE2420