SCPS268A September   2017  – February 2022 TIC10024-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  VS Pin
      2. 8.3.2  VDD Pin
      3. 8.3.3  Device Initialization
      4. 8.3.4  Device Trigger
      5. 8.3.5  Device Reset
        1. 8.3.5.1 VS Supply POR
        2. 8.3.5.2 Hardware Reset
        3. 8.3.5.3 Software Reset
      6. 8.3.6  VS Under-Voltage (UV) Condition
      7. 8.3.7  VS Over-Voltage (OV) Condition
      8. 8.3.8  Switch Inputs Settings
        1. 8.3.8.1 Input Current Source and Sink Selection
        2. 8.3.8.2 Input Enable Selection
        3. 8.3.8.3 Thresholds Adjustment
        4. 8.3.8.4 Wetting Current Configuration
      9. 8.3.9  Interrupt Generation and INT Assertion
        1. 8.3.9.1 INT Pin Assertion Scheme
        2. 8.3.9.2 Interrupt Idle Time (tINT_IDLE) Time
        3. 8.3.9.3 Microcontroller Wake-Up
        4. 8.3.9.4 Interrupt Enable / Disable And Interrupt Generation Conditions
        5. 8.3.9.5 Detection Filter
      10. 8.3.10 Temperature Monitor
        1. 8.3.10.1 Temperature Warning (TW)
        2. 8.3.10.2 Temperature Shutdown (TSD)
      11. 8.3.11 Parity Check And Parity Generation
      12. 8.3.12 Cyclic Redundancy Check (CRC)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Continuous Mode
      2. 8.4.2 Polling Mode
      3. 8.4.3 Additional Features
        1. 8.4.3.1 Clean Current Polling (CCP)
        2. 8.4.3.2 Wetting Current Auto-Scaling
  9. 9 Programming
    1. 9.1 SPI Communication Interface Buses
      1. 9.1.1 Chip Select ( CS)
      2. 9.1.2 System Clock (SCLK)
      3. 9.1.3 Slave In (SI)
      4. 9.1.4 Slave Out (SO)
    2. 9.2 SPI Sequence
      1. 9.2.1 Read Operation
      2. 9.2.2 Write Operation
      3. 9.2.3 Status Flag
    3. 9.3 Programming Guidelines
    4. 9.4 Register Maps
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Digital Switch Detection in Automotive Body Control Module
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
    3. 10.3 Systems Examples
      1. 10.3.1 Using TIC10024-Q1 in a 12 V Automotive System
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Receiving Notification of Documentation Updates
    2. 13.2 Community Resources
    3. 13.3 Trademarks
  14. 14Mechanical, Packaging, and Orderable Information

8.4.1 Continuous Mode

In continuous mode, wetting current is continuously applied to each enabled input channel, and the status of each channel is sampled sequentially (starting from the IN0 to IN23). The TIC10024-Q1 monitors enabled inputs and issues an interrupt (if enabled) if a switch status change event is detected. The wetting current setting for each input can be individually adjusted by configuring the WC_CFG0 and WC_CFG1 to the 0mA, 1mA, 2mA, 5mA, 10mA, or 15mA setting.

Figure 8-11 below illustrates an example of the timing diagram of the detection sequence in continuous mode. After the TRIGGER bit in register CONFIG is set to logic 1, it takes tSTARTUP to activate the wetting current for all enabled inputs. The wetting currents stay on continuously, while each input is routed to the comparator for sampling in a sequential fashion. After detection is done for an input, the switch status (below or above detection threshold) is stored in the register (IN_STAT_COMP) to be used as the default state for subsequent detection cycles. After the end of the first polling cycle, the INT pin is asserted low to notify the microcontroller that the default switch status is ready to be read. The SSC bit in INT_STAT register and the SPI status flag SSC are also asserted to logic 1. The polling cycle time (tPOLL) determines how frequently each input is sampled and can be configured in the register CONFIG.

GUID-7EF5C859-238E-4568-B70D-E43C8EAE5563-low.gifFigure 8-11 An Example Of The Detection Sequence In Continuous Mode

The INT_STAT register is cleared and INT pin de-asserted if a SPI READ command is issued to the register. Note the interrupt is always generated after the 1st detection cycle (after the TRIGGER bit in register CONFIG is set to logic 1). In subsequent detection cycles, the interrupt is generated only if switch status change is detected.

No wetting currents are applied to 0mA- configured inputs, although some biasing current (as specified by IIN_LEAK_0mA) may still flow in and out of the input. Threshold crossing monitoring is still performed for the input using the defined threshold(s). The 0mA setting is useful to utilize the integrated comparator to measure applied voltage on a specific input without being affected by the device wetting current.