JAJSIR6C September   2019  – August 2021 TPS8802

PRODUCTION DATA  

  1. 特長
  2. アプリケーション
  3. 概要
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  System Power-up
      2. 8.3.2  LDO Regulators
        1. 8.3.2.1 Power LDO Regulator
        2. 8.3.2.2 Internal LDO Regulator
        3. 8.3.2.3 Microcontroller LDO Regulator
      3. 8.3.3  Photo Chamber AFE
        1. 8.3.3.1 Photo Input Amplifier
        2. 8.3.3.2 Photo Gain Amplifier
      4. 8.3.4  LED Driver
        1. 8.3.4.1 LED Current Sink
        2. 8.3.4.2 LED Voltage Supply
      5. 8.3.5  Carbon Monoxide Sensor AFE
        1. 8.3.5.1 CO Transimpedance Amplifier
        2. 8.3.5.2 CO Connectivity Test
      6. 8.3.6  Boost Converter
        1. 8.3.6.1 Boost Hysteretic Control
        2. 8.3.6.2 Boost Soft Start
      7. 8.3.7  Interconnect Driver
      8. 8.3.8  Piezoelectric Horn Driver
        1. 8.3.8.1 Three-Terminal Piezo
        2. 8.3.8.2 Two-Terminal Piezo
      9. 8.3.9  Battery Test
      10. 8.3.10 AMUX
      11. 8.3.11 Analog Bias Block and 8 MHz Oscillator
      12. 8.3.12 Interrupt Signal Alerts
    4. 8.4 Device Functional Modes
      1. 8.4.1 Sleep Mode
      2. 8.4.2 Fault States
        1. 8.4.2.1 MCU LDO Fault
        2. 8.4.2.2 Over-Temperature Fault
    5. 8.5 Programming
    6. 8.6 Register Maps
      1. 8.6.1  REVID Register (Offset = 0h) [reset = 0h]
      2. 8.6.2  STATUS1 Register (Offset = 1h) [reset = 0h]
      3. 8.6.3  STATUS2 Register (Offset = 2h) [reset = 0h]
      4. 8.6.4  MASK Register (Offset = 3h) [reset = 0h]
      5. 8.6.5  CONFIG1 Register (Offset = 4h) [reset = 20h]
      6. 8.6.6  CONFIG2 Register (Offset = 5h) [reset = 2h]
      7. 8.6.7  ENABLE1 Register (Offset = 6h) [reset = 10h]
      8. 8.6.8  ENABLE2 Register (Offset = 7h) [reset = 0h]
      9. 8.6.9  CONTROL Register (Offset = 8h) [reset = 0h]
      10. 8.6.10 SLPTMR1 Register (Offset = 9h) [reset = 0h]
      11. 8.6.11 SLPTMR2 Register (Offset = Ah) [reset = 0h]
      12. 8.6.12 GPIO_AMUX Register (Offset = Bh) [reset = 0h]
      13. 8.6.13 CO_BATTEST Register (Offset = Ch) [reset = 0h]
      14. 8.6.14 CO Register (Offset = Dh) [reset = 0h]
      15. 8.6.15 VBOOST Register (Offset = Eh) [reset = F2h]
      16. 8.6.16 LEDLDO Register (Offset = Fh) [reset = 0h]
      17. 8.6.17 PH_CTRL Register (Offset = 10h) [reset = 0h]
      18. 8.6.18 LED_DAC_A Register (Offset = 11h) [reset = 0h]
      19. 8.6.19 LED_DAC_B Register (Offset = 12h) [reset = 0h]
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Photo Amplifier Component Selection
        2. 9.2.2.2 LED Driver Component Selection
        3. 9.2.2.3 LED Voltage Supply Selection
        4. 9.2.2.4 Boost Converter Component Selection
        5. 9.2.2.5 Regulator Component Selection
      3. 9.2.3 Application Curves
      4. 9.2.4 3V Battery Smoke and CO Alarm
        1. 9.2.4.1 Design Requirements
        2. 9.2.4.2 Detailed Design Procedure
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Photo Amplifier Layout
      2. 11.1.2 CO Amplifier Layout
      3. 11.1.3 Boost Converter Layout
      4. 11.1.4 Ground Plane Layout
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 ドキュメントの更新通知を受け取る方法
    2. 12.2 サポート・リソース
    3. 12.3 Trademarks
    4. 12.4 静電気放電に関する注意事項
    5. 12.5 用語集
  13. 13Mechanical, Packaging, and Orderable Information

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

Photo Amplifier Component Selection

To meet the 100-MΩ photoamplifier transconductance requirement, set the gain stage to 35x with PGAIN = 11. Because the application requires sub-nanoamp current detection, reference the photo amplifier to PREF and set PREF_SEL = 1. This reference offsets the input stage output by 50 mV and offsets the gain stage output by 225 mV. Because the application uses PREF, the gain stage amplification reduces to 32.25x. Divide 100 MΩ by 32.25x to get 3.1 MΩ. The gain is distributed across two resistors, therefore use a resistor with a value of approximately 1.55 MΩ. A 1.5-MΩ resistor is selected. The achieved transconductance is 96.8 MΩ. Use 10-pF of compensation capacitance in parallel with the 1.5-MΩ resistors. Use an oscilloscope with averaging to verify the photo amplifier is quickly settling but not overshooting. If the photo amplifier has overshoot, increase the compensation capacitance. If the photo amplifier is settling slowly, decrease the compensation capacitance.