DS2149AQN Maxim Integrated, DS2149AQN Datasheet
DS2149AQN
Specifications of DS2149AQN
Related parts for DS2149AQN
DS2149AQN Summary of contents
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GENERAL DESCRIPTION The DS2149 is a fully integrated LIU for long- haul or short-haul T1 applications over twisted- pair installations. It interfaces to two twisted-pair lines—one pair for transmit and one pair for receive through an appropriate interface. The ...
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DETAILED DESCRIPTION ................................................................................................. 4 2. OPERATING MODES......................................................................................................... 5 3. INITIALIZATION AND RESET............................................................................................ 9 4. REGISTER DEFINITIONS .................................................................................................. 9 5. TRANSMITTER................................................................................................................... 15 5 RANSMIT IGITAL 5 RANSMIT ONITORING 5 RANSMIT DLE ODE 5.4 ...
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Figure 1-1. Block Diagram....................................................................................................................................... 4 Figure 2-1. Hardware Mode Pinout ........................................................................................................................ 6 Figure 2-2. Serial Port Mode Pinout....................................................................................................................... 6 Figure 9-1. Serial Data Port Operation for Read Access.................................................................................. 18 Figure 9-2. Serial Data Port Operation for Write Access.................................................................................. 18 Figure ...
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DETAILED DESCRIPTION The DS2149 is a complete T1 line interface unit (LIU) for short-haul and long-haul applications. Receive sensitivity adjusts automatically to the incoming signal and can be limited to -18dB, -26dB, or -36dB. The device can generate the ...
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OPERATING MODES The DS2149 has several pins with multiple functions and names according to the selected operating mode. These operating modes are summarized in the tables below. Table 2-A. Operating Modes QRSS DISABLED PIN BIPOLAR TPOS ...
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Figure 2-1. Hardware Mode Pinout Figure 2-2. Serial Port Mode Pinout RPO S DS2149 MODE1 6 ...
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Table 2-C. Signal Descriptions PIN NAME I/O Master Clock. A 1.544MHz clock source with TTL levels is applied at this pin. This 1 MCLK I clock is used internally for both clock/data recovery and for jitter attenuation. Transmit Clock. A ...
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PIN NAME I/O LBO3. LBO0 through LBO3 are used to select transmitter output pulse, and receiver gain. Network Loopback Active. Output high when RLB is activated by in-band loop-up command present for 5 seconds. Output is reset ...
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INITIALIZATION AND RESET During power-up, all control registers are cleared, disabling the transmitter outputs. The device requires a master clock supplied to the MCLK input pin to operate the PLL. This master clock must be independent, free-running, and jitter ...
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CR1 (B010000): Control Register 1 MSb JASEL1 JASEL0 ENCENB SYMBOL POSITION JASEL1 CR1.7 JASEL0 CR1.6 ENCENB CR1.5 UNIENB CR1.4 L3 CR1.3 L2 CR1.2 L1 CR1.1 L0 CR1.0 Table 4-C. Jitter Attenuator Selection JASEL1 JASEL0 JITTER ATTENUATOR FUNCTION ...
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CR2 (B010001): Control Register 2 MSb RESET PAT1 PAT0 SYMBOL POSITION RESET CR2.7 PAT1 CR2.6 PAT0 CR2.5 TAIS CR2.4 ENLOOP CR2.3 ALB CR2.2 LLB CR2.1 RLB CR2.0 Table 4-F. Data Pattern Selection PAT0 PAT1 DATA SOURCE 0 0 TPOS/TNEG 0 ...
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IMR (B010011): Interrupt Mask Register MSb Z16D JALT DFMO SYMBOL POSITION 0 = Enable 16-zero detect interrupt Z16D IMR Disable 16-zero detect interrupt 0 = Enable jitter-attenuator limit-trip interrupt JALT IMR Disable jitter-attenuator limit-trip interrupt 0 ...
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SR (B010101): Status Register MSb — — DFMO SYMBOL POSITION — SR.7 — — SR.6 — DFMO SR.5 Set when transmitter detects open circuit. — SR.4 — QRSS SR.3 Set when the QRSS pattern is present at the receiver. AIS ...
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CR4 (B010111): Control Register 4 MSb — — — SYMBOL POSITION — CR4.7 — — CR4.6 — — CR4.5 — — CR4.4 — — CR4.3 — RCL threshold: 192 consecutive 0s RCL2048 CR4 RCL threshold: 2048 ...
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TRANSMITTER 5.1 Transmit Digital Data Interface Data is clocked into the device at the TCLK rate. In bipolar mode, TPOS and TNEG are the data inputs; in NRZ mode, TDATA is the data input. Input data can pass through ...
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Receive Digital-Data Interface Recovered data is routed to the RCL monitor. In software mode, data also goes through the alarm indication signal (AIS) monitor. The jitter attenuator can be enabled or disabled in the receive path or transmit path. ...
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SOFTWARE MODE The DS2149 operates in software mode when the MODE1 pin is pulled high. In software mode, a microprocessor controls the device and reads its status through the serial port, which provides access to the internal registers. The ...
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Figure 9-1. Serial Data Port Operation for Read Access Read Access CLKE = 0 SCLK SDI (lsb) SDO Read Access CLKE = SCLK CS SDI A1 ...
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Table 9-B. Control and Operation Mode Selection MODE1 MODE0 HARDWARE SOFTWARE NRZ BIPOLAR AMI B8ZS Low Low On Low High On Low Open On High Low Off High High Off High Open Off Open Low On Open High On Open ...
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Loopback Modes 10.1.1 Local Loopback (LLB) When local loopback is enabled (set LLB in CR2, or pull the LLB pin high), inbound data at the receiver inputs are ignored. TCLK and TPOS/TNEG pass through the jitter attenuator if enabled ...
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Figure 10-1. Loopbacks in the DS2149 Block Diagram RRING RTIP TRING TTIP 10.2 Internal Pattern Generation and Detection 10.2.1 Transmit Alarm-Indication Signal (TAIS) When TAIS is enabled (set TAIS in CR2, or pulling the TAIS pin high), the transmitter inputs ...
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In software mode, the device can generate an interrupt to indicate that the QRSS pattern synchronization has been declared or lost. Clearing the QRSS bit in the interrupt mask register enables the interrupt. Use the QPD output to increment an ...
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Alarm Monitoring 10.4.1 Receive-Carrier Loss (RCL) The receiver counts inbound 0s and declares RCL when the counter reaches 192. This applies to hardware mode and software mode if the RCL2048 bit is cleared in CR4. In software mode, setting ...
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NETWORK INTERFACE Transformer specifications are listed in resistance necessary for the basic interface and is associated with different transformer turns ratios. Smaller turns ratios result in lower power-supply requirements. However, series resistance provides added protection from potentially damaging voltages ...
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Figure 11-1. Basic Network Interface TRANSMIT LINE (larger winding toward the network) RECEIVE LINE Note 1: All resistor values are ±1%. Note 2: The R r resistors should be 50Ω each for T1 lines. Note 1mF if ...
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Figure 11-2. T1 Transmit Pulse Template 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -0.1 T1.102/87, T1.403, -0.2 CB 119 (Oct. 79), & I.431 Template -0.3 -0.4 -0.5 -500 -400 -300 MAXIMUM CURVE UI -0.77 ...
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Figure 11-3. Jitter Tolerance 1k 100 10 1 0.1 1 Figure 11-4. Jitter Attenuation 0dB -20dB -40dB -60dB 1 DS2149 TR 62411 (DEC. 90) TOLERANCE 10 100 1k FREQUENCY (Hz 100 1K FREQUENCY (Hz 10k ...
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DC CHARACTERISTICS ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground Operating Temperature Range for DS2149QN Storage Temperature Range Soldering Temperature Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These ...
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AC CHARACTERISTICS: SERIAL PORT (MODE1 = 5.0V ±5 -40°C to +85°C PARAMETER Setup Time CS to SCLK Setup Time SDI to SCLK Hold Time SCLK to SDI SCLK High/Low Time SCLK Rise/Fall Time ...
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AC CHARACTERISTICS: RECEIVE SIDE ( ±5 -40°C to +85°C PARAMETER RCLK Period RCLK Pulse Width (Note 6) RCLK Pulse Width (Note 7) Delay RCLK to RPOS, RNEG Valid Note 6: Jitter attenuator enabled in ...
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AC CHARACTERISTICS: TRANSMIT SIDE ( ±5 -40°C to +85°C PARAMETER TCLK Period TCLK Pulse Width TPOS/TNEG Setup to TCLK Falling or Rising TPOS/TNEG Hold from TCLK Falling or Rising TCLK Rise and Fall Times ...
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PACKAGE INFORMATION (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/DallasPackInfo ...