ltc2844 Linear Technology Corporation, ltc2844 Datasheet
ltc2844
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ltc2844 Summary of contents
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... Multiprotocol Transceiver DESCRIPTIO ® The LTC 2844 is a 4-driver/4-receiver multiprotocol trans- ceiver. The LTC2844 and LTC2846 form the core of a complete software-selectable DTE or DCE interface port that supports the RS232, RS449, EIA530, EIA530-A, V.35, V.36 or X.21 protocols. The LTC2844 operates from a 3.3V supply and supplies provided by the LTC2846 ...
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... Transmitter Output ...................................... Indefinite Receiver Output ........................................... Indefinite V ................................................................... 30 sec EE Operating Temperature Range LTC2844CG ............................................. LTC2844IG ......................................... – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS ture range, otherwise specifications are at T (Notes 2, 3) SYMBOL PARAMETER ...
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... GND OUT –0.25V V 0.25V, Power Off or O No-Cable Mode or Driver Disabled LTC2844C (Figures 2, 5) LTC2844I (Figures 2, 5) LTC2844C (Figures 2, 5) LTC28441 (Figures 2, 5) LTC2844C (Figures 2, 5) LTC2844I (Figures 2, 5) – t LTC2844C (Figures 2, 5) PHL LTC2844I (Figures 2, 5) (Figures 2, 5) – ...
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... CONDITIONS LTC2844C C = 50pF (Figures LTC2844I C = 50pF (Figures – t LTC2844C C = 50pF (Figures 2, 6) PHL L LTC2844I C = 50pF (Figures Open Circuit 3. 450 (Figure 450 (Figure GND O –0.25V V 0.25V, Power Off or O No-Cable Mode or Driver Disabled ...
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... RS530-A in DTE Mode (Two V.10 Drivers with Full Load Temperature EE 23.5 25.4 25.3 25.2 25.1 25.0 24.9 24.8 24.7 24.6 24.5 –40 – 100 TEMPERATURE ( C) 2844 G05 LTC2844 = 5V 3.3V 8V – V.28 in DCE Mode (Three V.28 Drivers with Full Load Data Rate ...
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... LTC2844 CTIO S V (Pin 1): Positive Supply for the Transceivers. Connect Pin 8 on LTC2846 supply. Connect capacitor to ground. V (Pin 2): Positive Supply Voltage for V.28. Connect Pin 7 on LTC2846 or 8V supply. Connect capacitor to ground. D1 (Pin 3): TTL Level Driver 1 Input. ...
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... D3/R1 A 20k 6k S3 20k 21 D3/R1 B Figure 2. V.11 Driver/Receiver AC Test Circuit 20 R2A R2B 18 R3A R3B 16 D4/R4 A 20k 2844 BD LTC2844 2844 F01 Figure 1. V.11 Driver Test Circuit 100pF 100 100pF ...
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... LTC2844 W U ODE SELECTIO 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. V.28/RS232 Cable 1 1 Note 1: Driver inputs are TTL level compatible. ...
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... O t SKEW Figure 5. V.11, V.35 Driver Propagation Delays f = 1MHz : t 10ns : t 10ns r f 1.65V Figure 6. V.11, V.35 Receiver Propagation Delays 0V – Figure 7. V.10, V.28 Driver Propagation Delays 1.65V Figure 8. V.10, V.28 Receiver Propagation Delays LTC2844 1.5V t PHL 90% 50% 10 SKEW 2844 F05 INPUT 0V t PHL OUTPUT 1.65V 2844 F06 1 ...
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... U A complete DCE-to-DTE interface operating in EIA530 mode is shown in Figure 9. The LTC2846 of each port is used to generate the clock and data signals. The LTC2844 is used to generate the control signals along with LL (local loop-back). Cable termination is used only for the clock and data signals. The control signals do not need any external resistors ...
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... Figure 10. The internal pull-up current sources will ensure a binary 1 when a pin is left unconnected and that the LTC2846/ LTC2844 enter the no-cable mode when the cable is removed. In the no-cable mode the LTC2846/LTC2844 supply current drops to less than 900 A and all driver outputs are forced into a high impedance state ...
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... Figure 11. Typical V.10 Interface The V.10 receiver configuration in the LTC2844 is shown in Figure 13. In V.10 mode switch S3 inside the LTC2844 is turned off.The noninverting input is disconnected inside the LTC2844 receiver and connected to ground. The cable termination is then the 30k input impedance to ground of the LTC2844 V.10 receiver. ...
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... In V.11 mode, all switches are off except S1 of the LTC2846’s receivers which connects a 103 differential termination impedance to the cable as shown in Figure The LTC2844 only handles control signals termination other than its V.11 receivers’ 30k input imped- ance is necessary. BALANCED INTERCONNECTING ...
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... LTC2844 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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... R2 If the RL, LL and TM signals are implemented, there are not 4.3k enough drivers and receivers available in the LTC2846/ LTC2844. In Figure 25, the required control signals are 2844 F22 handled by the LTC2845. The LTC2845 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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... DCE/DTE 3. GND LTC2844 3.3V 12 C10 DCE/DTE ...
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... C10 DCE/DTE LTC2844 13k 4.3k DTE DCE 2 TXD A RXD A 14 TXD B RXD B 24 SCTE A RXC A 11 SCTE B RXC B 15 TXC A TXC A 12 TXC B TXC B ...
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... LTC2844 U TYPICAL APPLICATIO 3. DTE_TXD/DCE_RXD DTE_SCTE/DCE_RXC DTE_TXC/DCE_TXC DTE_RXC/DCE_SCTE DTE_RXD/DCE_TXD DTE_RTS/DCE_CTS DTE_DTR/DCE_DSR DTE_DCD/DCE_DCD DTE_DSR/DCE_DTR DTE_CTS/DCE_RTS DTE_LL/DCE_RI DTE_RI/DCE_LL DTE_TM/DCE_RL DTE_RL/DCE_TM DCE/DTE Figure 25. Controller-Selectable Multiprotocol DTE/DCE Port with RL, LL, TM and DB-25 Connector MBR0520 5 BOOST 4 35 SHDN SWITCHING REGULATOR ...
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... CABLE WIRING FOR MODE SELECTION RS449, V. 3.3V 12 C10 CABLE WIRING FOR DTE/DCE SELECTION M2 14 DCE/DTE LTC2844 DTE DCE 2 TXD A RXD A 14 TXD B RXD B 24 RXC A SCTE A 11 SCTE B RXC B 15 TXC A TXC A 12 TXC B TXC B 17 ...
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... LTC2844 PACKAGE DESCRIPTIO 7.8 – 8.2 0.42 0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.09 – 0.25 (.0035 – .010) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE * DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED .152mm (.006") PER SIDE ** DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED .254mm (.010" ...