LTC1344 Linear Technology, LTC1344 Datasheet
LTC1344
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LTC1344 Summary of contents
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... When combined with the LTC1343, the LTC1344 forms a complete software-select- able multiprotocol serial port. A data bus latch feature allows sharing of the select lines between multiple inter- face ports. The LTC1344 is available in a 24-lead SSOP. , LTC and LT are registered trademarks of Linear Technology Corporation. RTS RL TM ...
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... Input Voltage (Logic Inputs) .... V EE Input Voltage (Load Inputs) .................................. 18V Operating Temperature Range LTC1344C ............................................... LTC1344I ........................................... – Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................. 300 C ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T ...
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... G05 V.35 Common Mode Inpedance vs Negative Supply Voltage ( 154 153 152 151 150 – 5.4 – 5.2 – 5.0 – 4.8 – 4.6 V VOLTAGE (V) EE 1344 G08 LTC1344 V.11 or V.35 Differential Mode Impedance vs Supply Voltage ( 105 104 103 4.6 4.8 5.0 5.2 5.4 V VOLTAGE (V) CC 1344 G03 V.35 Common Mode Impedance vs Common Mode Voltage ...
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... LTC1344 PIN FUNCTIONS M0 (Pin 1): TTL Level Mode Select Input. The data latched when LATCH is high. V (Pin 2): Negative Supply Voltage Input. Can connect EE directly to the LTC1343 V pin. EE R1C (Pin 3): Load 1 Center Tap. R1B (Pin 4): Load 1 Node B. R1A (Pin 5): Load 1 Node A. ...
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... 124 R2 51.5 B V.35 Mode Figure 3. LTC1344 Modes LTC1344 V. V.11 V.11 V.11 V. V.11 V. V.11 V.35 Z V.35 V.35 V.35 V. V.11 V. V.11 ...
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... FETs is difficult because the FETs must remain off even though the signal voltage is beyond the supply voltage for the FET drivers or the power is off. The LTC1344 solves the cable termination switching prob- lem via software control. The LTC1344 provides termina- tion for the V.10 (RS423), V.11 (RS422), V.28 (RS232) and V ...
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... V.35 differential generator with outputs A and B with ground C is connected to a differential receiver with ' ground C V.35 interface requires a T-network termination at the receiver end and the generator end. In V.35 mode both switches S1 and S2 in the LTC1344 are turned on as shown in Figure 11. ' con- The differential impedance measured at the connector must be 100 terminals A input impedance of the V ...
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... F11 The LATCH Pin The LATCH pin (21) allows the select lines (M0, M1, M2 and DCE/DTE shared with multiple LTC1344s, each with its own LATCH signal. When the LATCH pin is held low the select line input buffers are transparent. When the ...
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... M2 21 DCE/DTE 22 LATCH LATCH are shared by both chips. Each driver output and receiver input is connected to one of the LTC1344 termi- nation ports. Each electrical protocol can then be chosen using the digital select lines. 100pF 100pF LTC1344 ...
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... DCE CTRL 19 M2 LATCH 18 M1 INVERT 17 M0 423 SET GND LTC1344 21 LATCH DB-25 CONNECTOR DCE/ DTE DTE TXD A 14 TXD B 24 SCTE A 11 SCTE B 15 TXC A ...
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... DCE CABLE WIRING FOR MODE SELECTION MODE 24 EC V.35 EIA-530, RS449, V.36, X.21 RS232 LTC1344 13 LTC1344 21 LATCH DB-25 CONNECTOR DCE/ DTE DTE CC 2 TXD A RXD A 14 TXD B RXD B 24 SCTE A RXC A ...
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... LTC1334 Single Supply RS232/RS485 Transceiver LTC1343 Multiprotocol Serial Transceiver LTC1345 Single Supply V.35 Transceiver LTC1346A Dual Supply V.35 Transceiver LTC1344A Multiprotocol Cable Terminator, Pin Compatible to LTC1344 LTC1543 Multiprotocol Serial Transceiver LTC1544 Multiprotocol Serial Transceiver LTC1545 Multiprotocol Serial Transceiver Linear Technology Corporation 12 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www ...