LTC1544 Linear Technology, LTC1544 Datasheet
LTC1544
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LTC1544 Summary of contents
Page 1
... The LTC1546 includes software-selectable cable termination on- chip. The LTC1544 runs from a 5V supply and the charge pump on the LTC1543 or LTC1546. The part is available in a 28-lead SSOP surface mount package. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... Short-Circuit Duration Transmitter Output ..................................... Indefinite Receiver Output .......................................... Indefinite V .................................................................. 30 sec EE Operating Temperature Range LTC1544CG ............................................. LTC1544IG ........................................ – Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................. 300 C ELECTRICAL CHARACTERISTICS ture range, otherwise specifications are at T SYMBOL PARAMETER Supplies ...
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... 5V 8V – 7V for V.28, – 5.5V for V.10, V.11 (Notes CONDITIONS D1, D2, D3, D4 M0, M1, M2, DCE, INVERT = GND (LTC1544C) M0, M1, M2, DCE, INVERT = GND (LTC1544I) M0, M1, M2, DCE, INVERT = – 4mA 4mA ...
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... LTC1544 ELECTRICAL CHARACTERISTICS ture range, otherwise specifications are at T SYMBOL PARAMETER V.10 Driver V Output Voltage O V Output Voltage T I Short-Circuit Current SS I Output Leakage Current Rise or Fall Time Input to Output PLH t Input to Output PHL V.10 Receiver V Receiver Input Threshold Voltage TH V Receiver Input Hysteresis ...
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... D1 B (Pin 25): Driver 1 Noninverting Output (Pin 26): Driver 1 Inverting Output. GND (Pin 27): Ground. V (Pin 28): Negative Supply Voltage. Connect LTC1543 or to – 8V supply. Connect capacitor to ground 1544 F01 Figure 2. V.11 Driver/Receiver AC Test Circuit LTC1544 100pF 100 C A ...
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... LTC1544 TEST CIRCUITS Figure 3. V.10/V.28 Driver Test Circuit W U ODE SELECTIO LTC1544 MODE NAME M2 M1 Not Used (Default V.11 RS530A 0 0 RS530 RS449/V. V.28/RS232 Cable 1 1 Not Used (Default V.11 RS530A 0 0 RS530 RS449/V ...
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... DIFF 10% 1 SKEW Figure 5. V.11, V.35 Driver Propagation Delays f = 1MHz : t 10ns : t 10ns r f 1.5V Figure 6. V.11, V.35 Receiver Propagation Delays 0V – Figure 7. V.10, V.28 Driver Propagation Delays 0.8V Figure 8. V.10, V.28 Receiver Propagation Delays LTC1544 1.5V t PHL 90% 50% 10 SKEW 1544 F05 INPUT 0V t PHL OUTPUT 1.5V 1544 F06 1.5V t PLH ...
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... U A complete DCE-to-DTE interface operating in EIA530 mode is shown in Figure 9. The LTC1543 of each port is used to generate the clock and data signals. The LTC1544 is used to generate the control signals along with LL (Local Loop-back).The LTC1344A cable termination chip is used only for the clock and data signals because they must support V ...
Page 9
... Figure 10. The internal pull-up current sources will ensure a binary 1 when a pin is left unconnected and that the LTC1543/ LTC1544 and the LTC1344A enter the no-cable mode when the cable is removed. In the no-cable mode the LTC1543/LTC1544 supply current drops to less than 200 A and all LTC1543/LTC1544 driver outputs and LTC1344A resistive terminations are forced into a high impedance state ...
Page 10
... Figure 11. Typical V.10 Interface The V.10 receiver configuration in the LTC1544 is shown in Figure 13. In V.10 mode switch S3 inside the LTC1544 is turned off.The noninverting input is disconnected inside the LTC1544 receiver and connected to ground. The cable termination is then the 30k input impedance to ground of the LTC1544 V.10 receiver. ...
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... In V.28 mode all switches are off except S3 inside the LTC1543/LTC1544 which connects a 6k (R8) impedance to ground in parallel with 20k (R5) plus 10k (R6) for a combined impedance shown in Figure 17. The noninverting input is disconnected inside the LTC1543/ LTC1544 receiver and connected to a TTL level reference voltage for a 1.4V receiver trip point. LOAD GENERATOR CABLE ...
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... LTC1544 U U APPLICATIONS INFORMATION V.35 Interface A typical V.35 balanced interface is shown in Figure 18. A V.35 differential generator with outputs A and B with ground C is connected to a differential receiver with ' ' ground C , inputs A connected V.35 interface requires delta network termination at the receiver end and the generator end. The receiver ...
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... DTE vs DCE Operation The DCE/DTE pin acts as an enable for Driver 3/Receiver 1 in the LTC1543, and Driver 3/Receiver 1 and Driver 4/ Receiver 4 in the LTC1544. The INVERT pin in the LTC1544 allows the Driver 4/Receiver 4 enable to be high or low true polarity. LTC1544 and V as shown in Figure 21 ...
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... If the RL, LL and TM signals are implemented, there are not enough drivers and receivers available in the LTC1543/ LTC1544. In Figure 25, the required control signals are handled by the LTC1544 but the clock/data signals use the LTC1343. The LTC1343 has an additional single-ended driver/receiver pair that can handle two more optional control signals such as TM and LL ...
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... V EE C11 27 GND INVERT LTC1544 LTC1344A 21 LATCH TXD A (103) 14 TXD B 24 SCTE A (113) 11 SCTE B 15 TXC A (114) 12 TXC B 17 RXC A (115) 9 RXC B ...
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... TXD DCE/DTE C10 CTS DSR 5 D3 LTC1544 6 R1 DCD 7 R2 DTR 8 R3 RTS INVERT DCE/DTE Figure 23. Controller-Selectable DCE Port with DB-25 Connector 16 C6 ...
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... V EE C11 27 GND LTC1544 INVERT LTC1544 C8 100pF LTC1344A 21 LATCH DTE 2 TXD A 14 TXD B 24 SCTE A 11 SCTE B 15 TXC A 12 TXC B 17 RXC A ...
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... LATCH M2 18 INVERT M1 17 423SET GND C11 27 V GND LTC1544 INVERT DCE/DTE C8 100pF LTC1344A 21 LATCH ...
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... CABLE WIRING FOR MODE SELECTION D4 MODE PIN 18 PIN 21 V.35 PIN 7 PIN 7 RS449, V.36 NC PIN 7 RS232 PIN INVERT LTC1544 C8 100pF LTC1344A 21 LATCH DTE TXD A 14 TXD B 24 SCTE A 11 SCTE B ...
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... Perfect for Terminating the LTC1543 3-Driver/3-Receiver for Data and Clock Signals 3-Driver/3-Receiver for Data and Clock Signals Companion to LTC1544 for Data and Clock Signals Companion to LTC1544 for Data and Clock Signals 7.65 – 7.90 (0.301 – 0.311) ...