am79r251 Advanced Micro Devices, am79r251 Datasheet
am79r251
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am79r251 Summary of contents
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... Intelligent Access Am79R251 Intelligent Subscriber Line Interface Circuit (ISLIC DISTINCTIVE CHARACTERISTICS Monitor of two-wire interface voltages and currents supports — Voice transmission — Through chip ring generation — Programmable DC feed characteristics — Independent of battery — Current limited — Selectable off-hook and ground-key thresholds — ...
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... Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Operating Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Environmental Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Electrical Maximum Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Target Specifications (See note Relay Driver Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Am79R251 Transmission Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Am79R251 Ringing Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Am79R251 Current-Limit Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Am79R251 Fault Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Thermal-Management Equations (All Modes except Standby Timing Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Waveforms ...
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... All AC, DC, and signaling parameters are fully programmable via microprocessor or GCI interfaces on the ISLAC device. Additionally, the Am79R251 device has integrated self-test and line-test capabilities to resolve faults to the line or line circuit. The integrated test capability is crucial for remote applications where dedicated test hardware is not cost effective. DISTINCTIVE CHARACTERISTICS OF THE INTELLIGENT ACCESS™ ...
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... BLOCK DIAGRAMS Figure 1. Example Four-Channel Linecard Block Diagram 4 Am79R251 ...
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... Figure 2. Am79R251 Block Diagram IA sense 600 SA Fault Meas. HPA Active High Voltage VBP Power Amplifiers TMS Positive Supply BGND HPB Fault Meas sense BD IB 600 TMN Thermal Management Control TMP VBH High Neg Batt Sel VBL R3 RYE R2 R1 BGND ...
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... J = 32-pin plastic leaded chip carrier (PL032) DEVICE NAME/DESCRIPTION Am79R251 Intelligent Subscriber Line Interface Circuit Valid combinations list configurations planned supported in volume for this device. Consult the local AMD sales office to confirm availability of specific valid combinations, and to check on newly released valid combinations. Am79R251 Valid Combinations ...
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... CONNECTION DIAGRAM RYE TMS TMP TMN Am79R251 9 32-Pin PLCC Am79R251 IMT 27 26 ILG CREF 25 RSVD 24 23 HPB 22 HPA 21 VTX 7 ...
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... The LD pin controls the input latch and responds to a 3-level input. When the LD pin is a logic 1 ( >(Vref + 0.3V) ), the logic levels on P1–P3 latch into the Am79R251 control register bits that operate the mode-decoder. When the LD pin is a logic 0 ( <(Vref – 0.3V) ), the logic levels on P1– ...
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... GENERAL DESCRIPTION The Intelligent Access voice chipsets integrate all functions of the subscriber line. Two chip types are used to implement the linecard; an Am79R251 device and an ISLAC device. These provide the following basic functions: 1. The Am79R251: A high voltage, bipolar device that drives the subscriber line, maintains longitudinal balance and senses line conditions ...
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... Measured parameters can be compared to programmed threshold levels to set a pass/fail bit. The user can choose to send the actual measurement data directly to a higher level processor by way of the PCM voice channel. Both longitudinal and metallic resistance and capacitance can be measured, which allows leakage resistance, line capacitance, and telephones to be identified. 10 Am79R251 ...
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... CS2 BATP BATH DT1i U4 U6 RFBi B RSBi CBDi DT2i RMGPi RMGLi DHi BATH DLi BATL CBATHi CBATLi CBATPi BATP RTESTLi VOICE CHIPSETS LINECARD WITH Am79R251 +5V 3.3V VCC CREF RRXi SA RSN RHLai AD CHLbi RHLci RTi VREF CADi VSAB CHPi HPA VTX HPB CSSi BD ...
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... VREF LD VBH GND P1 VBL P2 P3 VBP RYE R2H R3H R1 BGND RSVD * CSS required for > 2.2 VRMS metering ** Connections shown for one channel RSRBi RSRC Am79R251 VOUTi DGND RHLbi VHLi AGND RHLdi CHLdi VCCA VCC +3.3 VDC VSABi VCCD VINi VLBi VIMTi VILGi U2 ISLAC ...
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... V Ceramic 22 nF 20% 100 V Ceramic 100 nF 20% 100 V Protector speed up capacitor 100 V Ceramic 510 1.2 W typ 750 k 2% 1/4 W Matched to within 0.2% for initial tolerance and typ 5 V Coil DPDT Am79R251 Comments ° ambient temperature range. 13 ...
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... VBL VCC On-Hook Transmission VBH Fixed Longitudinal Voltage VBL VCC On-Hook Active High Battery VBH VBL VCC Off-Hook Active Low Battery VBH RL = 294 VBL VCC Am79R251 fuse resistors, Min Typ Max Unit TBD TBD TBD mW TBD TBD TBD TBD mA TBD TBD ...
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... Thermal Resistance The junction to air thermal resistance of the Am79R251 in a 32-pin, PLCC package is 45°C/W. The typical junction to case thermal resistance is 14°C/W. Measured under free air convection conditions and without external heatsinking. Absolute Maximum Ratings Storage Temperature Ambient temperature, under bias ...
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... Load resistance on VSAB to Vref Note: Vloopmax: Maximum expected loop voltage in application; I Vpk: Peak signal voltage for application ± 5% –(Vloopmax + 6V + Vpk) to VBH V – – 140 V –100 mV to +100 minimum 20 k minimum off-hook loop resistance. LOOP Am79R251 ...
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... Disconnect, ISA = ISB/ILG Disconnect, ISB = 2 mA Condition Min VBH – ? 13. RSN 8. RSN 130 Standby mode 600 44 VBH B to Ground CREF – 1 2.0 –50 TBD Am79R251 Typ Max Unit V VBH–5 VBH– 16.13 10.8 12.96 250 375 µ 0.6 V ...
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... Zener Break Over, R1 Zener On Voltage, R1 Figure 5. Relay Driver Configuration R2 Figure 5A. Ring Relay 18 Condition Min Typ 25 mA/relay sink 1 relay on 0.225 3 relays on 0.4 40 mA/ relay sink 1 relay on 0.45 3 relays on 0.8 R2,R3 = BGND 0 RYE = VBH Iz = 100 A 6.6 7 RYE BGND Am79R251 Max Unit Note 0.3 0 0.7 1.0 3 100 µ ...
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... Am79R251 Transmission Specifications No. Item 1 RSN input impedance 2 VTX output impedance 3 Max loop current 4 Input impedance GND 5 2-4 wire gain 6 2-4 wire gain variation with frequency 7 2-4 wire gain tracking 8 4-2 wire gain 9 4-2 wire gain variation with frequency 10 4-2 wire gain tracking 11 Total harmonic distortion level ...
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... This parameter is tested at 1 kHz in production. Performance at other frequencies is guaranteed by characterization. 5. When the Am79R251 and ISLAC device is in the anti-sat operating region, this parameter is degraded. The exact degradation depends on system design. 6. –55 dBm gain tracking level not tested in production. This parameter is guaranteed by characterization and correlation to other tests. 7. This spec is valid from VBL or – ...
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... When the LD pin is more than 0.3 V above VREF (> (VREF + 0 P1–P3 must contain ISLIC control data C1, C2, and C3, which are latched into the last three bits of the Am79R251 control register. Connecting the LD pin to VREF locks the contents of the Am79R251 control register. ...
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... Disconnect This mode disconnects both A and B output amplifiers from the AD and BD outputs. The A and B amplifiers are shut down and the Am79R251 selects the low battery voltage at the VBL pin. In the Disconnect state, the currents on IMT and ILG represent the voltages on the SA and SB pins, respectively. These currents are scaled to produce voltages across ...
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... Control bits RD1, RD2, and RD3 do not affect the operating mode of the Am79R251. These signals usually perform the following functions. Table 3. Driver Descriptions Driver R1 A logic 1 on RD1 turns the R1 driver on and operates a relay connected between the R1 pin and VCCD. R1 drives the ring relay when external ringing is selected. ...
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... LD signal. 2. After a power-on reset or hardware reset, the relay outputs from the Am79R251 turn all relays off. An unassuming state is to place the relay control pins, which are level triggered reset state for all relays. ...
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... WAVEFORMS VCC VREF LD 0V Previous Relay Data P1,P2,P3 VREF tr SLD LD VREF t SDXSU P1,P2,P3 Relay Data State Data DETAIL A tf SLD t SLDPW t SDXHD Am79R251 Write State Register Lock Registers Write Relay Register New Relay Data Write State Register Write Relay Register 25 ...
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... Revision B to Revision C • Page 13, Linecard Parts List, Rows CHLbi and CHLdi: switched the numbers in the “Values” column. 26 .009 .015 .125 .140 .080 .095 SEATING PLANE .013 .021 .050 REF. Am79R251 .042 .056 .400 REF. .490 .530 16-038FPO-5 PL 032 DA79 SIDE VIEW 6-28-94 ae ...
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... The contents of this document are provided in connection with Advanced Micro Devices, Inc. ("AMD") products. AMD makes no representations or warranties with respect to the accuracy or completeness of the contents of this publication and reserves the right to make changes to speci- fications and product descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any in- tellectual property rights is granted by this publication. Except as set forth in AMD’ ...