xecom (1) XE0002D XE0002D august 2005 modular daa with 2/4 wire convertor description the XE0002D is a compact daa module designed for applications requiring voice, data or fax transfer. it complies with fcc part 68 rules for direct connection to the public switched telephone network and also supports leased line applications. the XE0002D provides a complete telephone interface. it includes the 2/4 wire convertor to separate transmit and receive signals, ring detection, integral switch hook and telephone line transformer. all of this circuitry is integrated into a module requiring only 1.25 inches of board space. features: ? small size: just 1.25 inches by 1.0 inches by 0.32 inches high ? fcc part 68 compliant ? user selectable 2-4 wire convertor ? active low ring detection ? integral switch hook ? supports v.32 data transfer ? supports both dial-up and leased line applications ? extended operating temperature range (-40c to +85c) available XE0002D block diagram jumpers j1 and j2 must be installed to connect the 2 to 4 wire convertor. ring detect ring detect tip ring hook hook - - switch switch loop loop curre nt curre nt holding holding circuit circuit te le pho ne te le pho ne line line transforme r transforme r 2/4 2/4 - - wi re wi re conve rter conve rter j1 j2 /oh xmit rcvr xfmr t1 t2 /ri
xecom (2) XE0002D XE0002D mechanical specifications XE0002D pin configuration vdd 1 2 0 tip vcc 2 /ri 3 (top view) rcvr 4 1 7 ring xmit 5 xfmr 6 t1 7 14 n/c oh 8 13 n/c gnd 9 1 2 n/c t2 10 11 n/c inches millimeters dim min max min max a 1.235 1.265 31.37 32.13 b 0.985 1.015 25.02 25.78 c 0.490 0.510 12.45 12.95 d 0.890 0.910 22.61 23.11 e 0.890 0.910 22.61 23.11 f 0.125 - 3.18 - g 0.040 0.060 1.02 1.52 h 0.165 0.185 4.19 4.70 j 0.090 0.110 2.29 2.79 k 0.020 0.025 0.51 0.64
xecom (3) XE0002D XE0002D pin descriptions pin name description 1 vdd vdd supplies -5 volt power to the XE0002D?s 2 to 4 wire converter. 2 vcc vcc supplies +5 volts power to the XE0002D 3 /ri ring indicate, output, active low, ttl. /ri indicates the XE0002D is receiving a ring signal. /ri remains low for the duration of each ring. 4 rcvr rcvr acts as the analog output from the XE0002D?s 2 to 4 wire converter. signals pass from the telephone line to the host via rcvr 5 xmit xmit provides the analog input to the XE0002D?s 2 to 4 wire converter. signals placed on xmit are sent out onto the telephone line. 6 xfmr xfmr is provided to connect the internal 2 to 4 wire converter to the telephone line transformer. a jumper is required from xfmr to t1 whenever the 2 to 4 wire circuit is required. 7 t1 t1 is one of two direct connections to the internal telephone line transformer. t1 must be connected to the XE0002D xfmr lead to use the internal 2 to 4 wire converter. if the 2 to 4 wire converter is not required, signals for the telephone line can be passed across t1 and t2. 8 oh hookswitch relay control. a high on oh closes the internal relay and connects the equipment to the telephone line. 9 gnd gnd provides the ground reference connection to the XE0002D. 10 t2 t2 is one of two direct connections to the internal telephone line transformer. t2 must be connected to ground to use the internal 2 to 4 wire converter. if the 2 to 4 wire converter is not required, signals for the telephone line can be passed across t1 and t2. 11-14 no connection 17 ring ring is one wire of the two-wire telephone line connection (rj11 pin 4). 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. xecom recommends 0.100 inch spacing between traces connected to ring and all other conductors to preserve this isolation 20 tip tip is one wire of the two-wire telephone line connection (rj11 pin 3). the telephone company places a dc "battery" voltage across tip and ring on all public switched telephone lines. the XE0002D accept this line battery voltage without regard to its polarity.
xecom (4) XE0002D XE0002D electrical specifications (vcc = 5v + 10%, ta = 0 to 70c) power supply current vcc 10 ma vdd 4 ma transmit insertion loss 600 ohm impedance, 1000 hz 0 db receive insertion loss 600 ohm impedance, 1000 hz 0 db line matching resistor (rm) for 600 ohm telephone line 340 ohms line impedance at 1000 hz, rm equal to 340 ohms 540 600 660 ohms without internal 2/4 wire convertor transhybrid loss attenuation between transmitter input and 10 18 db receiver output at 1khz with 600 ohm line termination transmit input impedance at xmit, 1800 hz 8 1 0 12 kohm receive output impedance at rcvr, 1800 hz 10 100 ohms ring detect sensitivity min. ac voltage between tip & ring 38 vrms type b ringer ring indicate output ring voltage present on tip and ring 0.2 0.5 volts hook switch control voltage on: (off-hook) 4.0 volts off: (on-hook) 0.8 volts hook switch control current off-hook 0.5 ma telephone line loop current off-hook 20 100 ma parameter conditions min typ max units XE0002D absolute maximum ratings storage temperature -25c to +85c operating temperature range 0c to +70c maximum lead temperature 260 o c (soldering 2 seconds per wave)
xecom (5) XE0002D XE0002D typical connection diagram with internal 2/4 wire converter modem analog front end XE0002D rj11 4 3 /ring receive transmit ohrly +5 volts 10 ohms, 1/2 w 470 pfd 3000 volts 470 pfd 3000 volts ferritebead ferritebead teccor p3100sc 10 ohms, 1/2 w -5 volts vdd tip vcc /ri rcvr xmit ring xfmr t1 oh gnd t2 j1 j2 XE0002D typical connection diagram without internal 2/4 wire converter XE0002D rj11 4 3 gpio0 rxan txan txap rxap gpio1 +5 volts 10 ohms, 1/2 w 470 pfd 3000 volts 470 pfd 3000 volts ferritebead ferritebead teccor p3100sc 10 ohms, 1/2 w vdd tip vcc /ri rcvr xmit ring xfmr t1 t2 gnd /oh r1 r2 note: r1 and r2 each equal one half of the ideal line matching impedance, 170 ohms. 42k 42k tdk 73m1903
xecom (6) XE0002D when developing a product to be connected to the telephone line, it is necessary to use a circuit described as a data access arrangement (daa) which is approved by the appropriate governmental agency. in the us, for example, this agency is the federal communications commission (fcc), while in canada it is the department of communications (doc). these agencies test and approve the product to ensure that it meets their specifications, thereby protecting the telephone system from damage and protecting the user from high voltage transients (such as lightning strikes) which may come down the telephone line. the XE0002D has been designed to meet all fcc part 68 requirements for hazardous voltage, surge protection and leakage current. if the system developed transmits data, or dtmf tones on the telephone line, the user must certify that the signals transmitted meet basic fcc requirements for maximum transmission levels, out of band energy and billing delay. full details may be obtained from the fcc under part 68 of the fcc rules and regulations, or in title 47 of the code of federal regulations, however the basic requirements are as follows: 1. maximum transmit level for the normal ?permissive? (standard) telephone line, equipment which transmits data (such as a modem) must not exceed a transmission level of -9 dbm. 2. out of band energy data equipment must not transmit ?out of band? energy on the telephone line which exceeds the following limits: frequency range max. power 200hz to 3990hz -9 dbm 3990hz to 4005hz -27 dbm 4005hz to 16khz -16 dbm 8khz to 94khz -47 dbm 86khz to 270khz -46 dbm 270khz to 6mhz -6 dbm 3. dtmf transmission level if the system is capable of dtmf dialing, the maximum dtmf transmission level must be less than 0 dbm averaged over a 3 second interval. 4. billing delay a delay of 2 seconds or greater is required after the time the XE0002D is taken ?off hook? and before any information is transmitted. this is required to ensure that billing information may be exchanged between telephone company central offices without interference. the user of the XE0002D must certify to the fcc that the final system meets the requirements of part 68 which include the criteria above as well as the high voltage protection provided by the XE0002D. this is generally accomplished through an independent testing lab which tests the system and submits the proper paperwork to the fcc for approval. since the XE0002D already complies with fcc part 68 rules, this is a relatively simple process. XE0002D fcc instructions
xecom (7) XE0002D copyright, xecom ? 2005 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. 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 pro- vided 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 rea- sonably expected to cause failure of the life support device or system, or to affect its safety or effectiveness. xecom incorporated 374 turquoise street, milpitas, ca 95035 ph:408-942-2200 fax:408-942-1346 email: info@xecom.com www.xecom.com
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