SLLS396G SEPTEMBER   1999  – December 2015 SN65LVDS104 , SN65LVDS105

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Selection Guide to LVDS Repeaters
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings—JEDEC
    3. 7.3  ESD Ratings—MIL-STD
    4. 7.4  Recommended Operating Conditions
    5. 7.5  Thermal Information
    6. 7.6  SN65LVDS104 Electrical Characteristics
    7. 7.7  SN65LVDS105 Electrical Characteristics
    8. 7.8  SN65LVDS104 Switching Characteristics
    9. 7.9  SN65LVDS105 Switching Characteristics
    10. 7.10 Dissipation Ratings
    11. 7.11 Typical Characteristics
  8. Parameter Measurement Information
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Fail Safe
    4. 9.4 Device Functional Modes
      1. 9.4.1 Input Level Translation
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Point-to-Point Communications
      2. 10.2.2 Design Requirements
      3. 10.2.3 Detailed Design Procedure
        1. 10.2.3.1  Bypass Capacitance
        2. 10.2.3.2  Driver Supply Voltage
        3. 10.2.3.3  Driver Input Voltage
        4. 10.2.3.4  Driver Output Voltage
        5. 10.2.3.5  Interconnecting Media
        6. 10.2.3.6  PCB Transmission Lines
        7. 10.2.3.7  Termination Resistor
        8. 10.2.3.8  Receiver Supply Voltage
        9. 10.2.3.9  Receiver Input Common-Mode Range
        10. 10.2.3.10 Receiver Input Signal
        11. 10.2.3.11 Receiver Output Signal
      4. 10.2.4 Application Curve
    3. 10.3 Multidrop Communications
      1. 10.3.1 Design Requirements
      2. 10.3.2 Detailed Design Procedure
        1. 10.3.2.1 Interconnecting Media
  11. 11Power Supply Recommendations
    1. 11.1 Coupling Capacitor Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Microstrip vs. Stripline Topologies
      2. 12.1.2 Dielectric Type and Board Construction
      3. 12.1.3 Recommended Stack Layout
      4. 12.1.4 Separation Between Traces
      5. 12.1.5 Crosstalk and Ground Bounce Minimization
      6. 12.1.6 Decoupling
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Related Links
    2. 13.2 Community Resources
    3. 13.3 Trademarks
    4. 13.4 Electrostatic Discharge Caution
    5. 13.5 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • PW|16
  • D|16
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9 Detailed Description

9.1 Overview

The SN65LVDS10x are a differential line receiver and a LVTTL input, respectively, connected to four differential signaling (LVDS) line drivers. These devices operate from a single 3.3-V supply. The input signal to the SN65LVDS104 is a differential LVDS signal; this device requires ±100 mV of input signal to determine the correct state of the received signal. The input signal to the SN65LVDS105 is an LVTTL signal. The outputs of both devices are four differential signals complying with the LVDS standard (TIA/EIA-644). The differential output signal operates with a signal level of 350 mV, nominally, at a common-mode voltage of 1.2 V. The intended application of this device and signaling technique is for point-to-point baseband data transmission over controlled impedance media of approximately 100 Ω. The transmission media may be printed-circuit board traces, backplanes, or cables. Having the drivers integrated into the same substrate, along with the low pulse skew of balanced signaling, allows extremely precise timing alignment of the signals repeated from the input. This is particularly advantageous in distribution or expansion of signals such as clock or serial data stream.

9.2 Functional Block Diagram

SN65LVDS104 SN65LVDS105 logic_dia_01_slls396.gif Figure 23. Example of Functional Block Diagram (SN65LVDS104)
SN65LVDS104 SN65LVDS105 logic_dia_02_slls396.gif Figure 24. Example of Functional Block Diagram (SN65LVDS105)

9.3 Feature Description

9.3.1 Fail Safe

A common problem with differential signaling applications is how the system responds when no differential voltage is present on the signal pair. The LVDS receiver is like most differential line receivers, in that its output logic state can be indeterminate when the differential input voltage is between –100 mV and 100 mV and within its recommended input common-mode voltage range. However, TI LVDS receivers handles the open-input circuit situation differently.

Open-circuit means that there is little or no input current to the receiver from the data line itself. This could be when the driver is in a high-impedance state or the cable is disconnected. When this occurs, the LVDS receiver pulls each line of the signal pair to near VCC through 300-kΩ resistors as shown in Figure 25. The fail-safe feature uses an AND gate with input voltage thresholds at about 2.3 V to detect this condition and force the output to a high-level regardless of the differential input voltage.

SN65LVDS104 SN65LVDS105 ai_open_cir_lls396.gif Figure 25. Open-Circuit Fail Safe of the LVDS Receiver

It is only under these conditions that the output of the receiver will be valid with less than a 100 mV differential input voltage magnitude. The presence of the termination resistor, Rt, does not affect the fail-safe function as long as it is connected as shown in Figure 25. Other termination circuits may allow a dc current to ground that could defeat the pullup currents from the receiver and the fail-safe feature.

9.4 Device Functional Modes

Table 2 lists the function tables for the SN65LVDS104 and 105 devices.

Table 2. Function Tables(1)

SN65LVDS104 SN65LVDS105
INPUT OUTPUT INPUT OUTPUT
VID = VA - VB xEN xY xZ A ENx xY xZ
X X Z Z L H L H
X L Z Z H H H L
VID ≥ 100 mV H H L Open H L H
–100 mV < VID < 100 mV H ? ? X L Z Z
VID ≤ –100 mV H L H X X Z Z
(1) H = high level, L = low level, Z = high impedance, ? = indeterminate, X = don't care
SN65LVDS104 SN65LVDS105 sch_dia_lls396.gif Figure 26. Equivalent Input and Output Schematic Diagrams

9.4.1 Input Level Translation

An LVDS receiver can be used to receive various other types of logic signals. Figure 27 through Figure 36 show the termination circuits for SSTL, HSTL, GTL, BTL, LVPECL, PECL, CMOS, and TTL.

SN65LVDS104 SN65LVDS105 ai_stub_lls396.gif Figure 27. Sub-Series Terminated (SSTL) or High-Speed Transceiver Logic (HSTL)
SN65LVDS104 SN65LVDS105 ai_center_lls396.gif Figure 28. Center Tap Termination
SN65LVDS104 SN65LVDS105 ai_gunn_lls396.gif Figure 29. Gunning Transceiver Logic (GTL)
SN65LVDS104 SN65LVDS105 ai_backpla_lls396.gif Figure 30. Backplane Transceiver
SN65LVDS104 SN65LVDS105 ai_lo_vol_lls396.gif Figure 31. Low-Voltage Positive Emitter-Coupled Logic (LVPECL)
SN65LVDS104 SN65LVDS105 ai_pos_em_lls396.gif Figure 32. Positive Emitter-Coupled Logic (PECL)
SN65LVDS104 SN65LVDS105 ai_cmos_lls396.gif Figure 33. 3.3-V CMOS
SN65LVDS104 SN65LVDS105 ai_5vcmos_lls396.gif Figure 34. 5-V CMOS
SN65LVDS104 SN65LVDS105 ai_5vttl_lls396.gif Figure 35. 5-V TTL
SN65LVDS104 SN65LVDS105 ai_lvttl_lls396.gif Figure 36. LVTTL