LTC2871CUHF#PBF Linear Technology, LTC2871CUHF#PBF Datasheet
LTC2871CUHF#PBF
Specifications of LTC2871CUHF#PBF
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LTC2871CUHF#PBF Summary of contents
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... RS232 levels. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Simultaneous Protocols and RS485 Termination Switching 1 ...
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LTC2870/LTC2871 ABSOLUTE MAXIMUM RATINGS Input Supplies ..................................................... –0. Generated Supplies V ................................................ ......................................................... 0.3V to –7. – V ..............................................................15V ........................................... –0. CAP ............................................. ...
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... LTC2870CUFD#TRPBF LTC2870IUFD#PBF LTC2870IUFD#TRPBF LTC2871CFE#PBF LTC2871CFE#TRPBF LTC2871IFE#PBF LTC2871IFE#TRPBF LTC2871CUHF#PBF LTC2871CUHF#TRPBF LTC2871IUHF#PBF LTC2871IUHF#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: For more information on tape and reel specifications, go to: ...
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LTC2870/LTC2871 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER Power Supply V Supply Voltage Operating Range CC V Logic Supply Voltage Operating Range L V Supply Current in Shutdown Mode CC V Supply Current in Transceiver Mode ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER R Terminating Resistor TERM RS232 Driver V Output Low Voltage OLD V Output High Voltage OHD Three-State (High Impedance) Output Current Output Short-Circuit Current RS232 Receiver Input Threshold Voltage ...
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LTC2870/LTC2871 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER RS485 AC Characteristics Maximum Data Rate t Driver Propagation Delay PLHD485 t PHLD485 Driver Propagation Delay Difference |t – PLHD485 PHLD485 t Driver Skew (Y to ...
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TYPICAL PERFORMANCE CHARACTERISTICS V Supply Current vs Supply CC Voltage in Shutdown Mode 30 25 H/F HIGH 20 15 H/F LOW 3.5 4 4.5 5 INPUT VOLTAGE (V) 28701 G01 V Supply Current CC vs RS232 ...
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LTC2870/LTC2871 TYPICAL PERFORMANCE CHARACTERISTICS RS485 Receiver Propagation Delay vs Temperature 3. 3. ...
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TYPICAL PERFORMANCE CHARACTERISTICS RS232 Driver Outputs Enabling and Disabling DX232 DOUT1 FEN = 1 5V/DIV DOUT2 DOUT1 FEN = 0 DOUT2 28701 G19 40μs/DIV TOP CURVES: FAST ENABLE DX232 BOTTOM CURVES: SHUTDOWN DX232 PIN FUNCTIONS LTC2870 LTC2870 LTC2871 PIN NAME ...
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LTC2870/LTC2871 PIN FUNCTIONS LTC2870 LTC2870 LTC2871 PIN NAME QFN TSSOP QFN DOUT1 23 DOUT2 485/232 4 7 RXEN 5 8 DXEN 6 9 ...
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BLOCK DIAGRAM 1.7V TO 5.5V (≤ V 0.1μF DXEN RXEN TE485 CONTROL H/F LOGIC 485/232 FEN LOOPBACK PATH RA RB LTC2870 ) 3V TO 5.5V CC 10μH 2.2μ PULSE-SKIPPING RT232 BOOST REGULATOR RT485 ...
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LTC2870/LTC2871 BLOCK DIAGRAM 1.7V TO 5.5V (≤ V 0.1μF DX232 DX485 RX232 RX485 CONTROL TE485 LOGIC H/F CH2 FEN LB DIN1 DI DIN2 LOOPBACK PATH ROUT1 RO ROUT2 12 LTC2871 10μH 2.2μ ...
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TEST CIRCUITS Y + GND DY/DI OR DRIVER – Figure 1. RS485 Driver DC Characteristics Figure 3. RS485 Receiver Input Current and Resistance (Note 5) Y DY/DI R DRIVER DIFF GND OR ...
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LTC2870/LTC2871 TEST CIRCUITS DY/DI OR DRIVER GND Z R DXEN/DX485 C L Figure 5. RS485 Driver Enable and Disable Timing Measurements ± RECEIVER CM B ± Figure 6. ...
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TEST CIRCUITS RECEIVER – B TE485 + – Figure 8. RS485 Termination Resistance and Timing Measurements (Note 5) DRIVER INPUT Figure 9. RS232 Driver Timing and Slew Rate Measurements DXEN/DX232 V AB ...
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LTC2870/LTC2871 TEST CIRCUITS RECEIVER RECEIVER INPUT OUTPUT RECEIVER OUTPUT –3V OR +3V RXEN/RX232 16 RECEIVER 1.5V INPUT t PHLR232 C L 90% RECEIVER OUTPUT 10% Figure 11. RS232 Receiver Timing Measurements RXEN/ R ½V L RX232 L GND OR V ...
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FUNCTION TABLES Table 1. LTC2870 Mode Selection Table RXEN FEN 485/232 DXEN ...
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LTC2870/LTC2871 FUNCTION TABLES Table 5. LTC2871 CH2 CONTROL RS232 RECEIVER INPUTS CH2 RX232 DX232 RIN1 Hi 5kΩ Hi 5kΩ 5kΩ Hi-Z 1 ...
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APPLICATIONS INFORMATION Overview The LTC2870 and LTC2871 are flexible multiprotocol trans- ceivers supporting RS485/RS422 and RS232 protocols. These parts can be powered from a single 3V to 5.5V supply with optional logic interface supply as low as 1.7V. An integrated ...
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LTC2870/LTC2871 APPLICATIONS INFORMATION Inrush Current and Supply Overshoot Precaution In certain applications fast supply slew rates are generated when power is connected. If the V than 4.5V and its rise time is faster than 10μs, the pins V and SW ...
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APPLICATIONS INFORMATION All devices also feature thermal shutdown protection that disables the drivers, receivers, and RS485 terminators in case of excessive power dissipation (see Note 6). RS485 Balanced Receiver with Full Failsafe Operation The LTC2870 and LTC2871 receivers use a ...
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LTC2870/LTC2871 APPLICATIONS INFORMATION Receiver Outputs The RS232 and RS485 receiver outputs are internally driven high ( low (to GND) with no external pull needed. When the receivers are disabled the output pin becomes Hi-Z with ...
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APPLICATIONS INFORMATION Logic Loopback A loopback mode connects the driver inputs to the re- ceiver outputs (non-inverting) for self test. This applies to both RS232 and RS485 transceivers. Loopback mode is entered when the LB pin is high and the ...
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LTC2870/LTC2871 TYPICAL APPLICATIONS 5.5V 1. Logic input pins not shown are tied to a valid logic state LTC2870 485/232 DXEN RXEN ...
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TYPICAL APPLICATIONS 5.5V 1. Logic input pins not shown are tied to a valid logic state LTC2870 RXEN DXEN TE485 H/F LB 485/232 RS RS 232 ...
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LTC2870/LTC2871 TYPICAL APPLICATIONS 5.5V 1. Logic input pins not shown are tied to a valid logic state LTC2871 CH2 H/F LB TE485 D R 485 DX485 ...
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TYPICAL APPLICATIONS 1. DXEN RXEN 485/232 H/F TE485 DY CONTROLLER Figure 38. LTC2870: Making Use of Shared I/O for Various Communication Configurations 1. DXEN RXEN ...
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LTC2870/LTC2871 TYPICAL APPLICATIONS V L CONTROLLER Figure 40. LTC2871: Various Communication Configurations V L CONTROLLER Figure 41. LTC2871: More Communication Configurations Using External Connections LTC2871 L CC RS232 DX232 FULL-DUPLEX ...
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TYPICAL APPLICATIONS 5.5V 1. Logic input pins not shown are tied to a valid logic state DX232 DX485 CH2 TE485 DI ROUT1 RXIN RIN1 RS232 ROUT1 ...
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LTC2870/LTC2871 TYPICAL APPLICATIONS LTC2871 DIN1 DOUT1 PORT 1 LOGIC ROUT1 INTERFACE DIN2 DOUT2 PORT 2A/2B LOGIC ROUT2 INTERFACE CH2 SELECT LINE 2A LTC2871 CH2 SELECT LINE 2B DIN2 DOUT2 ROUT2 DIN1 DOUT1 PORT 3 LOGIC ROUT1 INTERFACE Figure 44. RS232 ...
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TYPICAL APPLICATIONS 3V TO 5.5V 10μH 2.2μ 1. H/F 0.1μF TE485 DI RO DIN1 ROUT1 DIN2 ROUT2 1μF EE 1μF Figure 47. Typical Supply Connections with External Components Shown 3V ...
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LTC2870/LTC2871 PACKAGE DESCRIPTION 4.75 (.187) 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. ...
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PACKAGE DESCRIPTION 4.75 REF 6.60 ±0.10 4.50 REF SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ...
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LTC2870/LTC2871 PACKAGE DESCRIPTION 4.50 ± 0.05 3.10 ± 0.05 2.50 REF 2.65 ± 0.05 0.25 ±0.05 0.50 BSC RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 5.00 ...
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... ALL DIMENSIONS ARE IN MILLIMETERS Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. UHF Package 38-Lead Plastic QFN (5mm × ...
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... Switchable, 120Ω Termination Resistor, 15kV ESD 1Mbps, 2500V RMS www.linear.com ● 3. 0.1μ 120Ω RO GND 28701 TA02 Isolation with Integrated DC/DC Converter, Integrated, Isolation with Integrated DC/DC Converter, ±10kV ESD LT 1210 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 28701f ...