JAJSE97D June   2017  – May 2019 DAC8740H , DAC8741H

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      概略回路図
  4. 4 改訂履歴
  5. 5 概要（続き）
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
    1.     Pin Functions: DAC8740H
    2.     Pin Functions: DAC8741H
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  HART Modulator
      2. 9.3.2  HART Demodulator
      3. 9.3.3  FOUNDATION Fieldbus or PROFIBUS PA Manchester Encoder
      4. 9.3.4  FOUNDATION Fieldbus or PROFIBUS PA Manchester Decoder
      5. 9.3.5  Internal Reference
      6. 9.3.6  Clock Configuration
      7. 9.3.7  Reset and Power-Down
      8. 9.3.8  Full-Duplex Mode
      9. 9.3.9  I/O Selection
      10. 9.3.10 Jabber Inhibitor
    4. 9.4 Device Functional Modes
      1. 9.4.1 UART Interfaced HART
      2. 9.4.2 UART Interfaced FOUNDATION Fieldbus or PROFIBUS PA
      3. 9.4.3 SPI Interfaced HART
      4. 9.4.4 SPI Interfaced FOUNDATION Fieldbus or PROFIBUS PA
      5. 9.4.5 Digital Interface
        1. 9.4.5.1 UART
          1. 9.4.5.1.1 UART Carrier Detect
        2. 9.4.5.2 SPI
          1. 9.4.5.2.1 SPI Cyclic Redundancy Check
          2. 9.4.5.2.2 SPI Interrupt Request
    5. 9.5 Register Maps
      1. 9.5.1 CONTROL Register (Offset = 2h) [reset = 0x8042]
        1. Table 9. CONTROL Register Field Descriptions
      2. 9.5.2 RESET Register (Offset = 7h) [reset = 0x0000]
        1. Table 10. RESET Register Field Descriptions
      3. 9.5.3 MODEM_STATUS Register (Offset = 20h) [reset = 0x0000]
        1. Table 11. MODEM_STATUS Register Field Descriptions
      4. 9.5.4 MODEM_IRQ_MASK Register (Offset = 21h) [reset = 0x0024]
        1. Table 12. MODEM_IRQ_MASK Register Field Descriptions
      5. 9.5.5 MODEM_CONTROL Register (Offset = 22h) [reset = 0x0048]
        1. Table 13. MODEM_CONTROL Register Field Descriptions
      6. 9.5.6 FIFO_D2M Register (Offset = 23h) [reset = 0x0200]
        1. Table 14. FIFO_D2M Register Field Descriptions
      7. 9.5.7 FIFO_M2D Register (Offset = 24h) [reset = 0x0200]
        1. Table 15. FIFO_M2D Register Field Descriptions
      8. 9.5.8 FIFO_LEVEL_SET Register (Offset = 25h) [reset = 0x0000]
        1. Table 16. FIFO_LEVEL_SET Register Field Descriptions
      9. 9.5.9 PAFF_JABBER Register (Offset = 27h) [reset = 0x0000]
        1. Table 17. PAFF_JABBER Register Field Descriptions
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Design Recommendations
      2. 10.1.2 Selecting the Crystal or Resonator
      3. 10.1.3 Included Functions and Filter Selection
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 DAC8740H HART Modem
        2. 10.2.2.2 2-Wire Current Loop
        3. 10.2.2.3 Regulator
        4. 10.2.2.4 DAC
        5. 10.2.2.5 Amplifiers
        6. 10.2.2.6 Diodes
        7. 10.2.2.7 Passives
      3. 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 ドキュメントのサポート
      1. 13.1.1 関連資料
    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

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

9.3.3 FOUNDATION Fieldbus or PROFIBUS PA Manchester Encoder

FOUNDATION Fieldbus or PROFIBUS PA data is loaded into a transmit FIFO via UART or SPI interfaces which is translated into the Manchester encoded binary analog signals used in both FOUNDATION Fieldbus and PROFIBUS PA bus protocols through an internal Manchester encoder.

The Manchester encoder interacts with the DAC to transmit positive and negative amplitude signals, with respect to a positive common mode voltage, to create the Manchester encoded analog outputs at 31.25 kHz baud. A binary 0 is represented by a low-to-high transition and a binary 1 is represented by a high-to-low transition.

In both UART and SPI interfaced device, the encoder is activated any time there is data available in the transmit FIFO and the decoder is not receiving data. In order to prevent FIFO buffer overflow, for UART mode the CD pin acts as an interrupt to indicate when the FIFO level has exceed a programmed threshold in the packet initiation code. In SPI mode the transmit FIFO threshold programmed in the FIFO LEVEL SET register can trigger an interrupt on the IRQ pin. Once the IRQ interrupts is triggered, the MODEM STATUS register can then be read to determine the source of the interrupt, which includes a bit for the FIFO level in DB4. More details are explained in the respective Device Functional Modes sections.