xrt5894 Exar Corporation, xrt5894 Datasheet
xrt5894
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xrt5894 Summary of contents
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... Recommendation D Optional User Selectable LOS Declaration/Clearing Delay GENERAL DESCRIPTION The XRT5894 is an optimized four channel 3.3V line interface unit fabricated using low power CMOS technology. The device contains four independent E1 channels. Each channel performs the driver and receiver functions necessary to convert bipolar signals to logical levels and vice versa ...
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... Pulse RZ Mux Shaping 1 1 Figure 1. XRT5894 Block Diagram D LOSCNT (pin 45) is unconnected when LOSSEL is logic 1, or connected to an external clock when LOSSEL is logic 0. Transmitter Notes D Return loss exceeds ETSI 300 166 specification with a 1:2 ratio transformer and R4 are always 9.1W for both 75W and 120W applications ...
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PIN CONFIGURATION TXPOS4 TXNEG4 TXCLK4 GND TTIP4 V CC TRING4 GND GND TRING1 V CC TTIP1 GND TXCLK1 TXNEG1 TXPOS1 Rev. 1. LEAD THIN QUAD FLAT PACK ( 1.4 mm, TQFP) 3 ...
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... XRT5894 PIN DESCRIPTION Pin # Symbol Type Description 1 LOS1 O Receiver 1 Loss of Signal. Asserted during LOS condition. 2 RXPOS1 O Receiver 1 Positive Data Out. Positive RZ data output for channel 1. 3 RXNEG1 O Receiver 1 Negative Data Out. Negative RZ data output for channel Positive Supply (+3.3V or +5.0V + 5%). Digital circuitry. ...
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PIN DESCRIPTION (CONT’D) Pin # Symbol Type Description 35 GND Analog Ground. 36 TTIP3 O Transmitter 3 Positive Bipolar Output Positive Supply (+3.3V or +5.0V + 5%). Transmitter channel TRING3 O Transmitter 3 Negative Bipolar ...
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... XRT5894 ELECTRICAL CHARACTERISTICS Test Conditions 3.3V or 5. Symbol Parameter DC Electrical Characteristics Parameters V Voltage Supply CC V Voltage Supply CC Inputs V Input High Level IH V Input Low Level IL Outputs V Output High Level OH V Output Low Level OL Receiver Specifications RX Allowable Cable Loss CL RX Interference Margin ...
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ELECTRICAL CHARACTERISTICS Test Conditions 3.3V or 5. Symbol Parameter Power Specifications V =5.0V (Cont’ Power Consumption 120W C P Power Consumption 75W C P Power Consumption 120W C AC Electrical Characteristics V ...
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... Note: The same type 1:2 CT ratio device may be used at both receiver input and transmitter output. The following transformers have been tested with the XRT5894: HALO type TG26-1205(package contains two 1 CT:2 CT ratio transformers) Pulse type PE-65535 (1:2 CT ratio) Transpower Technologies type TTI 7154-R (1:2 CT ratio) Magnetic Supplier Information: HALO Electronics, Inc ...
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TXPOS (n) TXNEG ( TXCLK (n) TXOUT (n) RXIN (n) T5 RPOS (n) RXNEG (n) Rev. 1.10 TSU THO TSU TR TF TXPW T3 VTXOUT Figure 2. Transmit Timing Diagram Figure 3. Receive Timing ...
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... Rev. 1.10 75W Min. Typ For both 75 sistors are connected between each end of the transformer primary and the XRT5894 TTIP and TRING pins. 75W Min. Typ Table 4. Receiver Return Loss Specification D Each half of transformer secondary is terminated with 150 eration (resistors are 1% tolerance) ...
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... LOS condition will never be less than the range specified in the G.775 specification (10-255 pulse intervals). The LOS detection/clearing circuitry of the XRT5894 in “automatic” mode will detect LOS when the incoming signal has “no transitions” i.e. when the signal level is less ...
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... If a clock is not present at the TXCLK input (pin is left open), the part operates in the clockless mode. In this mode, RZ data should be supplied to the device. Each transmit channel of XRT5894 has a duty cycle correction circuitry. This enables the device to produce output bipolar pulses fully compliant with G.703 despite having TXCLK signal with 30% to 70% duty cycle ...
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... Transmitter output transformer secondary terminated with 120W All ones signal Receiver output looped backed into transmitter digital input Operation without transmitter clock (RZ data) Measurement made with a Tektronix TDS640 digital scope set to full bandwidth 1.2 1.0 0.8 0.6 0.4 0.2 0 -0.2 -244 Rev. 1.10 -122 0 122 Time (ns) Figure 5. XRT5894 Output Pulse 13 244 ...
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... Table 5. Transmitter Output Return Loss Measurements Notes 2048KHz This data shows that the XRT5894 is fully compliant with the ETSI Output Return Loss Specification for E1 operation with either 75W or 120W loads. Rev. 1.10 This configuration was used for both 75W and 120W measurements ...
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The following pictures show typical results of measurements that made over a 50 KHz to 3.5MHz frequency range. Figure 6 shows a return loss better than 20dB at low frequencies that decreases to about 12dB at 3.5MHz. Since the source ...
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... XRT5894 Output Transformer Selection A 1:2 ratio transformer is recommended for both 75W and 120W operation because the transmitter, when equipped with this device, meets both the ITU G.703 output pulse amplitude requirement and, the ETSI return loss specification. Although a center--tapped output transformer is not required, choosing a part with a center-tapped secondary allows the use of the same type of unit at the receiver input ...
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This may be further simplified Figure 10. Equivalent Circuit Where int ext Therefore Req ...
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... XRT5894 Seating Plane A 1 Note: The control dimension is the millimeter column Rev. 1.10 64 LEAD THIN QUAD FLAT PACK ( 1.4 mm, TQFP) Rev. 2. INCHES SYMBOL MIN MAX A 0.055 0.063 A 0.002 0.006 1 A 0.053 0.057 2 B 0.005 0.009 C 0.004 ...
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... While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized ...