JAJSH84G May   2014  – October 2019 SN65HVD70 , SN65HVD71 , SN65HVD73 , SN65HVD74 , SN65HVD76 , SN65HVD77

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     ブロック図
  4. 4 改訂履歴
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions — SOIC-8 and MSOP-8
    2.     Pin Functions — MSOP–10
    3.     Pin Functions — SOIC-14
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information — D Packages
    5. 7.5  Thermal Information — DGS and DGK Packages
    6. 7.6  Power Dissipation
    7. 7.7  Electrical Characteristics
    8. 7.8  Switching Characteristics — 400 kbps
    9. 7.9  Switching Characteristics — 20 Mbps
    10. 7.10 Switching Characteristics — 50 Mbps
    11. 7.11 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
      1. 9.4.1 Equivalent Circuits
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1.      Master Enable Control
      2.      Slave Enable Control
      3. 10.2.1 Design Parameters
        1. 10.2.1.1 Data Rate and Bus Length
        2. 10.2.1.2 Stub Length
        3. 10.2.1.3 Bus Loading
        4. 10.2.1.4 Receiver Failsafe
        5. 10.2.1.5 Transient Protection
      4. 10.2.2 Detailed Design Procedure
      5. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13デバイスおよびドキュメントのサポート
    1. 13.1 デバイス・サポート
      1. 13.1.1 デベロッパー・ネットワークの製品に関する免責事項
    2. 13.2 関連リンク
    3. 13.3 ドキュメントの更新通知を受け取る方法
    4. 13.4 コミュニティ・リソース
    5. 13.5 商標
    6. 13.6 静電気放電に関する注意事項
    7. 13.7 Glossary
  14. 14メカニカル、パッケージ、および注文情報

9.4 Device Functional Modes

For the SN65HVD70, SN65HVD73, and SN65HVD76, when the driver enable pin, DE, is logic high, the differential outputs Y and Z follow the logic states at data input D. A logic high at D causes Y to turn high and Z to turn low. In this case the differential output voltage defined as VOD = V(Y) – V(Z) is positive. When D is low, the output states reverse, Z turns high, Y becomes low, and VOD is negative.

When DE is low, both outputs turn high-impedance. In this condition the logic state at D is irrelevant. The DE pin has an internal pulldown resistor to ground, thus when left open the driver is disabled (high-impedance) by default. The D pin has an internal pullup resistor to VCC, thus, when left open while the driver is enabled, output Y turns high and Z turns low.

Table 1. Driver Function Table SN65HVD70, SN65HVD73, SN65HVD76

INPUT ENABLE OUTPUTS FUNCTION
D DE Y Z
H H H L Actively drives the bus high
L H L H Actively drives the bus low
X L Z Z Driver disabled
X OPEN Z Z Driver disabled by default
OPEN H H L Actively drives the bus high by default

When the receiver enable pin, RE, is logic low, the receiver is enabled. When the differential input voltage defined as VID = V(A) – V(B) is positive and higher than the positive input threshold, VIT+, the receiver output, R, turns high. When VID is negative and less than the negative and lower than the negative input threshold, VIT–, the receiver output, R, turns low. If VID is between VIT+ and VIT– the output is indeterminate.

When RE is logic high or left open, the receiver output is high-impedance and the magnitude and polarity of VID are irrelevant. Internal biasing of the receiver inputs causes the output to go failsafe-high when the transceiver is disconnected from the bus (open-circuit), the bus lines are shorted (short-circuit), or the bus is not actively driven (idle bus).

Table 2. Receiver Function Table SN65HVD70, SN65HVD73, SN65HVD76

DIFFERENTIAL INPUT ENABLE OUTPUT FUNCTION
VID = V(A) – V(B) RE R
VIT+ < VID L H Receives valid bus High
VIT– < VID < VIT+ L ? Indeterminate bus state
VID < VIT– L L Receives valid bus Low
X H Z Receiver disabled
X OPEN Z Receiver disabled by default
Open-circuit bus L H Fail-safe high output
Short-circuit bus L H Fail-safe high output
Idle (terminated) bus L H Fail-safe high output

For the SN65HVD71, HVD74, and HVD77, the driver and receiver are fully enabled, thus the differential outputs Y and Z follow the logic states at data input D at all times. A logic high at D causes Y to turn high and Z to turn low. In this case the differential output voltage defined as VOD = V(Y) – V(Z) is positive. When D is low, the output states reverse, Z turns high, Y becomes low, and VOD is negative. The D pin has an internal pullup resistor to VCC, thus, when left open while the driver is enabled, output Y turns high and Z turns low.

Table 3. Driver Function Table SN65HVD71, SN65HVD74, SN65HVD77

INPUT OUTPUTS FUNCTION
D Y Z
H H L Actively drives the bus High
L L H Actively drives the bus Low
OPEN H L Actively drives the bus High by default

When the differential input voltage defined as VID = V(A) – V(B) is positive and higher than the positive input threshold, VIT+, the receiver output, R, turns high. When VID is negative and less than the negative input threshold, VIT–, the receiver output, R, turns low. If VID is between VIT+ and VIT– the output is indeterminate. Internal biasing of the receiver inputs causes the output to go failsafe-high when the transceiver is disconnected from the bus (open-circuit), the bus lines are shorted (short-circuit), or the bus is not actively driven (idle bus).

Table 4. Receiver Function Table SN65HVD71, SN65HVD74, SN65HVD77

DIFFERENTIAL INPUT OUTPUT FUNCTION
VID = V(A) – V(B) R
VIT+ < VID H Receives valid bus High
VIT– < VID < VIT+ ? Indeterminate bus state
VID < VIT– L Receives valid bus Low
Open-circuit bus H Fail-safe high output
Short-circuit bus H Fail-safe high output
Idle (terminated) bus H Fail-safe high output