L7554 AGERE [Agere Systems], L7554 Datasheet
L7554
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L7554 Summary of contents
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... A spare, uncommitted op amp is included for meter pulse filtering. The device is being offered in two versions, based upon maximum battery. The L7554AP is guaranteed to –60 V, and the L7554BP is guaranteed to –72 V. The device is available in a 44-pin PLCC package built by using complementary bipolar (CBIC) process. ...
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... L7554 Low-Power SLIC Content Features .................................................................................................................................................................. 1 Description ............................................................................................................................................................... 1 Pin Information ......................................................................................................................................................... 4 Functional Description .............................................................................................................................................. 6 Absolute Maximum Ratings ..................................................................................................................................... 6 Recommended Operating Conditions ..................................................................................................................... 7 Electrical Characteristics ......................................................................................................................................... 7 Ring Trip Requirements ..................................................................................................................................... 11 Test Configurations ............................................................................................................................................... 12 Applications ........................................................................................................................................................... 14 Design Considerations ....................................................................................................................................... 16 Characteristic Curves......................................................................................................................................... 17 dc Applications ................................................................................................................................................... 20 Battery Feed.................................................................................................................................................... 20 Overhead Voltage .......................................................................................................................................... 20 Adjusting Overhead Voltage ........................................................................................................................... 21 Adjusting dc Feed Resistance......................................................................................................................... 22 Adjusting Overhead Voltage and dc Feed Resistance Simultaneously .......................................................... 22 Loop Range ...
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... RING GROUND ICM DETECTOR Lucent Technologies Inc. POWER CONDITIONING & REFERENCE – –1 V/ SPARE OP AMP A = –4 ADJUST STATE CONTROL + – + – Figure 1. Functional Diagram L7554 Low-Power SLIC DCOUT 3 RECTIFIER T XI 9.6 VITR 0.1 µF C EXTERNAL SN – XMT + – RCVN 1 + RCVP B0 BATTERY FEED ...
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... L7554 Low-Power SLIC Pin Information V CC RCVP RCVN TXI LCTH V REG DCOUT V BAT PR Table 1. Pin Descriptions Pin Symbol Type Current-Limit Program Input. A resistor to DCOUT sets the dc current limit of the PROG device — Power Supply RCVP I Receive ac Signal Input (Noninverting). This high-impedance input controls the ac differential voltage on Tip and Ring ...
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... Forward Battery Slowdown. A 0.1 F capacitor from FB2 to AGND and from FB1 to AGND will ramp the polarity reversal transition for added flexibility in applications requiring quiet polarity reversal. If not needed, the pin can be left open. Lucent Technologies Inc. Description and connect a capacitor to AGND to filter 50/60 Hz. If unused, the pin can CC L7554 Low-Power SLIC . CC 5 ...
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... L7554 Low-Power SLIC Functional Description Table 2. Input State Coding Powerup, Forward Battery. Normal talk and battery feed state. Pin PT is positive with respect to PR. On-hook transmission is enabled Powerup, Reverse Battery. Normal talk and battery feed state. Pin PR is positive with respect to PT ...
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... This parameter is not tested in production guaranteed by design and device characterization. Lucent Technologies Inc. Min –40 4.75 –24 –24 — 5 — 150 Min — — — — — — — — JA L7554 Low-Power SLIC Typ Max Unit — 5.0 5. –40 –60 –48 – LIM 2.2 Vrms ...
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... LOOP Programmability Range Accuracy (20 mA < I < 40 mA) LIM Powerup Open Loop Voltage Levels Common-mode Voltage Differential Voltage –48 V, Temperature = 25 C BAT V = –72 V, Temperature = 85 C (L7554BP) BAT Disconnect State PT Resistance (V < V < BAT PT PR Resistance (V < V < BAT PR Ground Start State ...
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... LCTH to pin DCOUT. LCTH from pin ICM2 CM CC Min — — — — — — — L7554 Low-Power SLIC Typ Max Unit –125 –127 V/A — 200 mV — — — –0.2 – ...
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... L7554 Low-Power SLIC Electrical Characteristics Table 8. ac Feed Characteristics Parameter 1 ac Termination Impedance 2 Longitudinal Impedance Total Harmonic Distortion—200 kHz Off-hook On-hook Transmit Gain kHz (PT/PR to VITR) Transmit Accuracy in dB Transmit Accuracy in dB, Full Temperature Range Receive + Gain kHz (RCVP to PT/PR) Receive – ...
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... The circuits in Figure 3 will not cause ringing trip. Lucent Technologies Inc. (continued) Symbol TIP SWITCH CLOSES < TIP = –33 V, loop BAT TIP L7554 Low-Power SLIC Min Typ Max –0.5 0.4 0.7 2.0 2 — –115 –200 — –60 –100 0 0.2 0.4 2.4 — ...
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... DCOUT RCVP I PROG LCTH NLC NRDET RGDET RTSP CF1 RTSN I CF2 CM VTX TXI FB2 FB1 0.1 µF Figure 4. L7554 Basic Test Circuit DISCONNECT BYPASS CAP + V M – S 12-2335.a (C) Data Sheet March 1997 XMT RCV 10 k 0.1 µF 0.1 µ ...
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... MHz DEVICE IN POWERUP MODE, 600 Figure 8. RFI Rejection Lucent Technologies Inc. BASIC TEST CIRCUIT V S ------ - V M 12-2584 (C) PT BASIC TEST CIRCUIT 600 PR TERMINATION 12-2586 (C) L7554 Low-Power SLIC I LONG – BASIC TEST CIRCUIT – LONG ...
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... L7554 Low-Power SLIC Applications R PROG 3 66 PROG 14 DCOUT R 12 LCTH LCTH 24 0.1 µ TIP L7581 250 V PROT RELAY RING TSP 2 RTSP R TS1 C C RTS2 RTS1 402 0.27 µF 0.022 µF 31 RTSN R CF2 R TSN TS2 2 ...
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... R RTS1 With RTS1 Provides 60 Hz filtering for ring ground detection. Digital output pull-up resistor. Sets ring ground detection threshold. L7554 Low-Power SLIC Function , sets ac termination impedance. RCV , sets receive gain sets ac termination impedance RCV , forms second 2 Hz filter pole. ...
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... L7554 Low-Power SLIC Applications (continued) Design Considerations Table 11 shows the design parameters of the application circuit shown in Figure 11. Components that are adjusted to program these values are also shown. Table 11. 600 Design Parameters Design Parameter Loop Closure Threshold dc Loop Current Limit dc Feed Resistance ...
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... Figure 15. 7551 Typical V 0 –10 –20 –30 –40 –50 –60 –70 – 12-2829 (C) Figure 16. 7551 Typical V L7554 Low-Power SLIC CURRENT LIMIT SPEC. BELOW LIMIT 4 100 1000 10 10 FREQUENCY (Hz) Power Supply Rejection CC CURRENT LIMIT SPECIFICATION RANGE BELOW CURRENT LIMIT ...
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... L7554 Low-Power SLIC Applications (continued) Characteristic Curves (continued LOOP CLOSURE THRESHOLD RESISTOR, R Note –48 V. BAT Figure 17. Loop Closure Program Resistor Selection 2000 1500 1000 STILL AIR 47 C/W 500 100 AMBIENT TEMPERATURE, T Note: Tip lead is open – ...
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... Figure 23. Longitudinal Balance Resistor Mismatch 12-3052 ( 300 cu. ft./ min 0.0 120 140 180 160 ( C) A Figure 24. Longitudinal Balance vs. Protection 12-2825 (C) L7554 Low-Power SLIC 49 dB, RP MATCHED TO 1.5 58 dB, RP MATCHED TO 0 PROTECTION RESISTOR VALUE ( ) Requirements 0.5 1.0 1.5 2.0 PROTECTION RESISTOR MISMATCH ( ) Resistor Mismatch 100 120 12-3019 (C) 2 ...
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... L7554 Low-Power SLIC Applications (continued) dc Applications Battery Feed The dc feed characteristic can be described by – ------------------------------------------- - Rdc + + – ---------------------------------- - where loop current loop voltage. T battery voltage magnitude. BAT V = overhead voltage. This is the difference between ...
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... Figure 27. Equivalent Circuit for Adjusting the The overhead voltage is programmed by using the fol- lowing equation --------------- - dBm 20 10 1000 (4.0 V typ.). SAT is the 40 2 2.2 L7554 Low-Power SLIC tolerance of 0 nominal SAT . In the case of –5 V, the BAT 30% DCR R2 –5 V Overhead Voltage V = 6.5 – DCR ...
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... L7554 Low-Power SLIC Applications (continued) dc Applications (continued) Adjusting dc Feed Resistance The dc feed resistance may be adjusted with the help of Figure 28 30% DCR R3 DCOUT Figure 28. Equivalent Circuit for Adjusting the dc Feed Resistance -------------------- Rdc 113 500 = + --------------------------------- - = 113 + 500 ...
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... A slightly TSP The above equation is shown graphically in Figure 18. It applies for the case of Tip open. The more general equation can be used in ground key application to detect a common-mode current I L7554 Low-Power SLIC is repeated the positive compar ...
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... L7554 Low-Power SLIC Applications (continued) ac Design There are four key ac design parameters. Termination impedance is the impedance looking into the 2-wire port of the line card set to match the impedance of the telephone loop in order to minimize echo return to the telephone set. Transmit gain is measured from the 2-wire port to the PCM highway, while receive gain is done from the PCM highway to the transmit port ...
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... V L7554 SLIC ATT7564 SLIC XMT –0.4 V/mA – – SN VITR AGND + + RCVN – RCVP + R GN L7554 SLIC L7554 Low-Power SLIC VFXIN – VFXIP + HB1 R RCV VFR (PWROP T7513 CODEC VFXIN – VFXIP ...
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... L7554 Low-Power SLIC Applications (continued) ac Design (continued) Example 1, Real Termination The following design equations refer to the circuit in Figure 32. Use these to synthesize real termination impedance. Termination Impedance --------- - – ---------------------------------- - -------- - Receive Gain --------- - g = rcv ------------------------------------------------------------------ - ...
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... Data Sheet March 1997 Outline Diagram 44-Pin PLCC Controlling dimensions are in millimeters. PIN #1 IDENTIFIER Lucent Technologies Inc. 17.65 MAX 16.66 MAX ZONE 0.51 MIN 1.27 TYP 0.53 TYP MAX L7554 Low-Power SLIC 16.66 MAX 17.65 MAX 4.57 MAX SEATING PLANE 0.10 5-2506r7 (C) 27 ...
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... L7554 Low-Power SLIC Ordering Information Device Part No. ATTL7554AP Low-Power SLIC, –60 V ATTL7554AP–TR* Low-Power SLIC, –60 V ATTL7554BP Low-Power SLIC, –72 V ATTL7554BP–TR* Low-Power SLIC, –72 V *Devices on tape and reel must be ordered in 1000-piece increments. For additional information, contact your Microelectronics Group Account Manager or the following: INTERNET: http://www ...