SLVSF25C September   2019  – August 2021 TPS8802

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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. 7 Typical Characteristics
  8. 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. 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 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.2.3 Microcontroller LDO Regulator

The microcontroller LDO (MCU LDO) powers the internal digital input and output buffers (IO buffers) and external MCU that controls and programs the TPS8802. Connect a 1-µF capacitor to VMCU to stabilize the output. The MCU LDO can be programmed to output 1.5 V, 1.8 V, 2.5 V, and 3.3 V. The default MCU LDO setting is determined by the configuration on the MCUSEL pin (see Table 8-1). After the device is powered, the MCU LDO voltage can be changed using the VMCUSET register. The MCU LDO can also be disabled using the MCU_DIS register.

The MCU LDO output VMCU powers the IO buffers on SCL, SDA, CSEL, INT_MCU, GPIO, LEDEN, HBEN, and HORNFB. The IO buffers level shift signals from the digital core to a level suitable for the microcontroller and signals from the microcontroller to a level suitable for the digital core. In general, connect VMCU to the microcontroller supply voltage to guarantee logic level compatibility. If the MCU LDO is disabled, connect an external supply to VMCU. This external supply can be a 3-V battery. Connecting a 3-V battery directly to VMCU allows the MCU LDO to be disabled, saving some power in the system. When a 3-V battery is connected to VMCU, set the MCU LDO to 1.5 V or 1.8 V on power-up. The battery voltage overrides the MCU LDO without excess power draw.

The MCU LDO has a power good signal MCU_PG that indicates whether the MCU LDO is above 85% the regulation voltage. A 125-µs deglitch filter prevents noise from affecting the MCU_PG signal. If MCU_PG is low after 10 ms of changing the MCU LDO voltage or enabling the MCU LDO, the MCU_ERR flag is set high. If the MCU_ERR flag is high and MCUERR_DIS is low, the MCU LDO fault state is entered. See Section 8.4.2.1 section for more information.