SCHS463 May   2025 CD3268A , CD3269A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Requirements
  7. 6 Parameter Measurement Information
    1. 6.1 eN-MIC Microphone Integrated Noise Measurement
    2. 6.2 Current Measurements
    3. 6.3 MICPWR Output Voltage Measurement
    4. 6.4 Tone Mode Threshold Measurements
    5. 6.5 Impedance Measurements
    6. 6.6 Tone Mode Output Measurements
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Tone Mode Start-up Timing
      2. 7.3.2 Authentication
      3. 7.3.3 Shunt Regulator
      4. 7.3.4 Power-on-reset
    4. 7.4 Device Functional Modes
      1. 7.4.1 Button Mode
      2. 7.4.2 Tone Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
      2. 9.1.2 Development Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

7.4.1 Button Mode

When the CD326x detects a MIC pin voltage below 2.35V (typ), the CD326x shorts the MIC and REM pins together and disables all other inputs and outputs. When a button press event occurs, the DC voltage on the microphone bias line changes according to the button being pressed. Table 8-2 shows the corresponding DC voltage for a given button press when using the resistor values in Figure 7-4. This DC level can then be detected by a specially enabled audio interface connected to the microphone bias line (MIC pin).

Switch S0 is a unique switch (typically controlled by a specially enabled audio interface) that shorts the MIC pin to ground. When Switch S0 shorts the MIC pin to ground, the specially enabled audio interface removes power from the CD326x. When power recovers, the CD326x enters button mode or tone mode depending on the voltage detected at the MIC pin.

Table 7-1 Typical Switch Voltage Values (Button mode)
Switch ClosedMIC Pin Voltage (V) (1)
S00
S11.510
S21.603
S31.690
S41.779
(1) VMICBIAS is the voltage on the MIC pin: 2.0V (typ)
CD3268A CD3269A Recommended Button Mode Resistor Values
≤1% tolerance resistors recommended
Figure 7-4 Recommended Button Mode Resistor Values