xrt59l91 Exar Corporation, xrt59l91 Datasheet
xrt59l91
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xrt59l91 Summary of contents
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... Requirements Compliant with the ITU-T G.703 EOS Over- voltage protection requirements GENERAL DESCRIPTION The XRT59L91 is an optimized single-chip analog E1 line interface unit (LIU) fabricated using low power, 3.3V CMOS technology. The LIU IC consists of both a Transmitter and a Receiver function. The Transmit- ter accepts a TTL or CMOS level signal from the Terminal Equipment ...
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... XRT59L91 RTIP Recei Receive Equaliz ve Equalizer RRing er Loca Local Loop l Loop Back LLoop Back TTIP TRing Figure 1. XRT59L91 Block Diagram Rev. 1.0.0 RxLO S Peak Detector/ Peak Slice Detect Detector/ Slicer Detector r or Pulse Shaping Pulse Circuit Circui Shaping t ...
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... The Terminal Equipment should apply bit-wide NRZ pulses on this input pin, whenever the Terminal Equipment needs to transmit a “positive- polarity” pulse onto the line via TTIP and TRing output pins. The XRT59L91 device will sample this input pin upon the falling edge of the TCLK signal. Clockless Mode - The Terminal Equipment should apply RZ pulses to this input pin, anytime the Terminal Equipment needs to transmit a “ ...
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... Terminal Equipment needs to transmit a “negative- polarity” pulse onto the line via TTIP and TRing output pins. Local Loopback Input Select: This input pin permits the user to configure the XRT59L91 device to operate in the “Local Loopback” Mode; in order to support Diagnostic Operations. ...
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... The XRT59L91 device will use this pin, along with TRing, to transmit a bipolar line signal, via a 1:2 step-up transformer. Transmitter Power Supply Pin: 3. Transmit Ring Output: The XRT59L91 device will use this pin, along with TTIP, to transmit a bipolar line signal, via a 1:2 step-up transformer. Transmitter Ground Pin 5 ...
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... XRT59L91 AC ELECTRICAL CHARACTERISTICS 25°C Unless otherwise specified Parameter TClk Clock Period TClk Duty Cycle Transmit Data Setup Time Transmit Data Hold Time Transmit Data Prop. Delay Time - RZ data Mode - NRZ data Mode (clock mode) TClk Rise Time(10%/90%) TClk Fall Time(90%/10%) ...
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... XRT59L91 Test Conditions Cable attenuation @ 1024KHz per ITU-G.775 Below nominal pulse amplitude of 3.0V for 120 and 2.37V for 75 applications. With -18dB interference signal added. With 6dB cable loss per ITU-G.703 ...
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... Mode The user can configure the XRT59L91 device to operate in the “Clocked” mode by simply applying a 2.048MHz clock signal to the “TxClk” input pin. The XRT59L91 device contains detectioncircuitry that sense activity on the “TxClk” line. If this circuit senses activity on the “TxClk” line, then the XRT59L91 will automatically be operating in the “ ...
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... TxPO S TxNEG TClk Figure 2. Illustration on how the XRT59L91 Device Samples the data on the In general, if the XRT59L91 device samples a “1” on the TxPOS input pin, then the “Transmit Section” of the device will ultimately generate a positive polarity pulse via the TTIP and TRing output pins (across a 1:2 transformer). Conversely, if the XRT59L91 device samples a “ ...
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... XRT59L91 Figure 3, indicates that when the user is operating the XRT59L91 device in the “Clockless” Mode, then the Terminal Equipment must do the following. Not apply a signal on the “TxClk” line. When applying a pulse (to either the TxPOS or TxNEG input pin), apply an RZ pulse to the appropriate input pin ...
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... TxNEG 1 TxLineClk TxClk XRT59L91 Figure 5. Illustration of how to interface the Transmit Section of the XRT59L91 device to the Line (for “75 ” Applications) Rev. 1.0.0 1.2 Interfacing the Transmit Section of the XRT59L91 device to the Line ITU-T G.703 specifies that the E1 line signal can be transmitted over coaxial cable and terminated with 75 or transmitted over twisted-pair and terminated with 120 ...
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... Figure 6. Illustration of how to interface the Transmit Section of the XRT59L91 device to the Line (for “120 ” Applications) Notes: 1. Figures 5 and 6 indicate that for both “75 and “120 ” applications, the user should connect a 9.1 resistor, in series, between the TTIP/TRing outputs and the transformers ...
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... Singapore 368324 Tel: 65-287-8998 FAX: 65-280-0080 Rev. 1.0.0 Value 1:2 Isolation Package Type Transpower Technologies Corporate Office 9410 Prototype Drive, Ste #1 Reno, NV 89511 Tel: (800)511-7308 or (775)852-0140 Fax: (775)852-0145 www.trans-power.com HALO Electronics HALO Electronics P.O. Box 5826 Redwood City, CA 94063 Tel: (650)568-5800 FAX: (650)568-6161 13 XRT59L91 ...
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... oss o f Sig RT5 9L91 Figure 7. Recommended Schematic for Interfacing the Receive Section of the XRT59L91 Device to the Line for 75 Applications (Transformer-Coupling) Rev. 1.0.0 2.1 Interfacing the Receive Section to the Line The design of the XRT59L91 device permits the user to transformer-couple or capacitive-couple the Re- ceive Section to the line ...
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... nal R xLO S XRT59L91 Figure 9. Recommended Schematic for Interfacing the Receive Section of the XRT59L91 Device to the Line for 75 Applications (Capacitive-Coupling) Rev. 1.0 ...
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... XRT59L91 device will declare an LOS Condition, (by driving the “RxLOS” output pin “high”) if the received line signal amplitude drops to – 35dB or below. Further, the XRT59L91 device will clear the LOS Condition if the signal amplitude rises back up to –12dB or above. Figure 10 presents an illustration of G ...
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... Terminal Equip- ment” via the “RxPOS and RxNEG output pins. If the “Receive Section” of the XRT59L91 device has received a “Positive-Polarity” pulse, via the RTIP and Rev. 1.0.0 clear the LOS indicator within 10 to 255 UI after restoration of the incoming line signal ...
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... Loop B ack LLoop TTIP TR ing Figure 12. Illustration of the “Local Loop-back” within the XRT59L91 Device Rev. 1.0.0 Mode) into the XRT59L91 device via the TxPOS, TxNEG and TxCLK input pins. This data will be processed through the “Transmit Terminal Input Inter- face” and the “Pulse Shaping” circuit. Finally, this data will be output to the line via the TTIP and TRing output pins ...
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... TTIP TR ing Figure 13. Illustration of the “Remote Loop-back” path, within the XRT59L91 Device It should be noted that during “Remote Loop-back” operation, any data which is input via the RTIP and Rev. 1.0.0 “RxPOS” and “RxNEG” output pins. Additionally, this data will also be internally looped back to the “ ...
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... XRT59L91 4.0 Shutting off the Transmitter The XRT59L91 device permits the user to shut the “Transmit Driver” within the Transmit Section of the chip. This feature can be useful for system redundancy design considerations or during diagnostic testing. The user can activate this feature by either of the following ways ...
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... APPLICATIONS INFORMATION Figures 16, 17 and 18, provide example schematics on how to interface the XRT59L91 device to the line, under the following conditions: Receiver is Transformer-coupled unbalanced line. Receiver is Transformer-coupled to a 120 balanced line. Receiver is Capacitive-coupled unbalanced line Rev ...
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... T xLin oss XRT59L91 Figure 16. Illustration on how to interface the XRT59L91 Device to the Line (Receiver is Transformer-coupled unbalanced line) Rev. 1.0 TIP ...
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... ign RT59L91 Figure 17. Illustration on how to interface the XRT59L91 Device to the Line (Receiver is Transformer-coupled to a 120 balanced line) Rev. 1.0 ...
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... XRT59L91 Figure 18. Illustration on how to interface the XRT59L91 Device to the Line (Receiver is Capacitive-coupled unbalanced line) Rev. 1.0 TIP ...
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... Rev. 1.0.0 XRT59L91 25 ...
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... XRT59L91 Rev. 1.0.0 Notes 26 ...
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... Rev. 1.0.0 Notes 27 XRT59L91 ...
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... XRT59L91 EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration purposes and may vary depending upon a user’ ...