JAJSF33B August   2017  – July 2018 THS3491

PRODUCTION DATA.  

  1. 特長
  2. アプリケーション
  3. 概要
    1.     Device Images
      1.      標準的な任意波形発生器の出力駆動回路
      2.      高調波歪みと周波数との関係
  4. 改訂履歴
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics: VS = ±15 V
    6. 7.6 Electrical Characteristics: VS = ±7.5 V
    7. 7.7 Typical Characteristics: ±15 V
    8. 7.8 Typical Characteristics: ±7.5 V
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power-Down (PD) Pin
      2. 8.3.2 Power-Down Reference (REF) Pin
      3. 8.3.3 Internal Junction Temperature Sense (TJ_SENSE) Pin
    4. 8.4 Device Functional Modes
      1. 8.4.1 Wideband Noninverting Operation
      2. 8.4.2 Wideband, Inverting Operation
      3. 8.4.3 Single-Supply Operation
      4. 8.4.4 Maximum Recommended Output Voltage
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Driving Capacitive Loads
      2. 9.1.2 Video Distribution
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 PowerPAD™ Integrated Circuit Package Design Considerations (DDA Package Only)
        1. 11.1.1.1 PowerPAD™ Integrated Circuit Package Layout Considerations
        2. 11.1.1.2 Power Dissipation and Thermal Considerations
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 ドキュメントのサポート
      1. 12.1.1 関連資料
    2. 12.2 ドキュメントの更新通知を受け取る方法
    3. 12.3 コミュニティ・リソース
    4. 12.4 商標
    5. 12.5 静電気放電に関する注意事項
    6. 12.6 Glossary
  13. 13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)
  • DDA|8
  • RGT|16
発注情報

Wideband Noninverting Operation

The THS3491 is a 900-MHz current-feedback operational amplifier that is designed to operate from a power supply of ±7 V to ±16 V.

Figure 61 shows the THS3491 in a noninverting gain configuration of 5 V/V which is used to generate the majority of the performance curves. Most of the curves are characterized using signal sources with a 50-Ω source impedance and measurement equipment presenting a 50-Ω load impedance.

THS3491 ths3491-rgt-noninverting-gain.gifFigure 61. Wideband Noninverting Gain Configuration (5 V/V)

Current-feedback amplifiers are highly dependent on the RF feedback resistor for maximum performance and stability. Table 2 shows the optimal resistor values for RF and RG at different gains to achieve maximum bandwidth with minimal peaking in the frequency response. Use lower RF values for higher bandwidth. Note that this can cause additional peaking and a reduction in phase margin. Conversely, increasing RF decreases the bandwidth but phase margin increases and stability improves. To gain further insight on the feedback and stability analysis of current-feedback amplifiers like the THS3491, see the Current-feedback Amplifiers section of TI Precision Labs.

Table 2. Recommended Resistor Values for Minimum Peaking and Optimal Frequency Response
With RLOAD = 100 Ω

GAIN (V/V) RGT PACKAGE DDA PACKAGE
RG (Ω) RF (Ω) RG (Ω) RF (Ω)
2 976 976 2.1k 2.1k
5 143 576 200 798
10 54.9 499 78.7 704
20 20 383 29.4 564