ltc2845 Linear Technology Corporation, ltc2845 Datasheet
ltc2845
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ltc2845 Summary of contents
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... Software-Selectable Multiprotocol Transceiver DESCRIPTIO ® The LTC ceiver. The LTC2845 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 LTC2845 operates from a 3.3V supply and supplies provided by the LTC2846. This part is available in a 36-lead SSOP and 38-lead (7mm x 5mm) QFN package ...
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... Short-Circuit Duration Transmitter Output ..................................... Indefinite – 0.3V to 6.5V Receiver Output .......................................... Indefinite –10V to 0.3V V .................................................................. 30 sec EE – 0.3V to 10V Operating Temperature Range LTC2845C ............................................... 0.3V) LTC2845I ........................................... – Storage Temperature Range ................ – 150 C + 0.3V) Lead Temperature (Soldering, 10 sec)................. 300 0.3V 0.3V ORDER PART ...
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... Power Off or O No-Cable Mode or Driver Disabled LTC2845C (Figures 2, 5) LTC2845I (Figures 2, 5) LTC2845C (Figures 2, 5) LTC28451 (Figures 2, 5) LTC2845C (Figures 2, 5) LTC2845I (Figures 2, 5) – t LTC2845C (Figures 2, 5) PHL LTC2845I (Figures 2, 5) (Figures 2, 5) LTC2845 = – 7V for V.28, – 5.5V for V.10, V.11 ...
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... A,B –10V V 10V A,B (Figures 2, 6) LTC2845C C = 50pF (Figures LTC2845I C = 50pF (Figures LTC2845C C = 50pF (Figures LTC2845I C = 50pF (Figures – t LTC2845C C = 50pF (Figures 2, 6) PHL L LTC2845I C = 50pF (Figures Open Circuit 3. 450 (Figure 450 (Figure GND O – ...
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... DATA RATE (kBd) 2845 G02 RS530-A in DCE Mode (Three V.10 Drivers with Full Load Temperature EE 34.6 34.4 34.2 34.0 33.8 33.6 33.4 33.2 33.0 –40 – TEMPERATURE ( C) 2845 G05 LTC2845 = – 7V for V.28, – 5.5V for V.10, V.11 EE MIN TYP MAX 0.8 2 0.1 0 100 150 500 = 5V 3.3V 8V ...
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... LTC2845 PIN FUNCTIONS (G-36/QFN-38 Packages) V (Pins 1, 19/Pins 17, 36): Positive Supply for the CC Transceivers. Connect to V Pin 8 on LTC2846 supply. Connect capacitor to ground. V (Pin 2/Pin 37): Positive Supply Voltage for V.28. DD Connect to V Pin 7 on LTC2846 or 8V supply. Connect capacitor to ground. ...
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... R2B 26 R3A R3B 24 D4A 23 R4A 20k R5A 20k D5A Figure 4. V.10/V.28 Receiver Test Circuit 2845 BD LTC2845 2845 F01 Figure 1. V.11 Driver Test Circuit 100pF 100 100pF ...
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... LTC2845 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 MODE NAME ...
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... SKEW Figure 5. V.11 Driver Propagation Delays f = 1MHz : t 10ns : t 10ns r f 1.65V Figure 6. V.11 Receiver Propagation Delays 0V – Figure 7. V.10, V.28 Driver Propagation Delays 1.65V Figure 8. V.10, V.28 Receiver Propagation Delays LTC2845 1.5V t PHL 90% 50% 10 SKEW 2845 F05 INPUT 0V t PHL OUTPUT 1.65V 2845 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 LTC2845 is used to generate the control signals along with LL (Local Loop-Back), RL (Remote Loop-Back), TM (Test Mode) and RI (Ring Indicate). Cable termination is used only for the clock and data signals because they must support V ...
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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/ LTC2845 enters the no-cable mode when the cable is removed. In the no-cable mode the LTC2846/LTC2845 supply current drops to less than 1000 A and all driver outputs are forced into a high impedance state. ...
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... U U APPLICATIONS INFORMATION The V.10 receiver configuration in the LTC2845 is shown in Figure 13. In V.10 mode switch S3 inside the LTC2845 is turned off. The noninverting input is disconnected inside the LTC2845 receiver and connected to ground.The cable termination is then the 30k input impedance to ground of the LTC2845 V.10 receiver. BALANCED ...
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... LTC2846/LTC2845 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 LTC2846/ LTC2845 receiver and connected to a TTL level reference voltage for a 1.4V receiver trip point. V.35 Interface A typical V.35 balanced interface is shown in Figure 18 ...
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... W U DTE vs DCE Operation A 51.5 The DCE/DTE pin acts as an enable for Driver 3/Receiver 1 in the LTC2846, and Driver 3/Receiver 1 in the LTC2845. S1 The LTC2846/LTC2845 can be configured for either DTE 51.5 or DCE operation in one of two ways: a dedicated DTE or B DCE port with a connector of appropriate gender port ...
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... D2 DTR D3 LTC2845 R1 DCD R2 DSR R3 CTS C10 M1 D4ENB DCE/DTE R4EN LTC2845 13k 4.3k 2 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 3 RXD A (104) 16 RXD B ...
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... C4 3 LTC2846 3. DCE/DTE GND CTS D1 D2 DSR D3 LTC2845 R1 DCD R2 DTR R3 RTS C10 M1 D4ENB DCE/DTE R4EN 13k 4.3k 2 RXD A (104) ...
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... DD DTE_RTS/DCE_CTS D1 D2 DTE_DTR/DCE_DSR D3 LTC2845 R1 DTE_DCD/DCE_DCD R2 DTE_DSR/DCE_DTR R3 DTE_CTS/DCE_RTS D4 DTE_LL/DCE_RI R4 DTE_RI/DCE_LL DTE_TM/DCE_RL R5 D5 DTE_RL/DCE_TM D4ENB M2 NC DCE/DTE R4EN LTC2845 13k 4. –7.5V C4 3.3 F DTE DCE 2 TXD A RXD A 14 TXD B RXD B 24 SCTE A RXC A 11 SCTE B RXC B ...
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... LTC2845 PACKAGE DESCRIPTION 7.8 – 8.2 0.42 0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.09 – 0.25 0.55 – 0.95 (.0035 – .010) (.022 – .037) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) 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 ...
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... REF 0.00 – 0.05 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC2845 0.70 0.05 PACKAGE OUTLINE 3.15 0.10 0.435 0.18 ...
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... Software-Selectable Multiprotocol Transceiver LTC2844 3.3V Software-Selectable Multiprotocol Transceiver LTC2846 3.3V Software-Selectable Multiprotocol Transceiver LTC2847 Software-Selectable Multiprotocol Transceiver with 3.3V Digital Interface Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 DCD DTR RTS RXD LTC2845 ...