SBOS772C August   2017  – May 2019 INA1650-Q1 , INA1651-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Simplified Internal Schematic
  3. 3 Description
    1.     CMRR Histogram (5746 Channels)
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions: INA1650-Q1
    2.     Pin Functions: INA1651-Q1
  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 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Audio Signal Path
      2. 7.3.2 Supply Divider
      3. 7.3.3 EMI Rejection
      4. 7.3.4 Electrical Overstress
      5. 7.3.5 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Single-Supply Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Input Common-Mode Range
      2. 8.1.2 Common-Mode Input Impedance
      3. 8.1.3 Start-Up Time in Single-Supply Applications
      4. 8.1.4 Input AC Coupling
      5. 8.1.5 Supply Divider Capacitive Loading
    2. 8.2 Typical Applications
      1. 8.2.1 Line Receiver for Differential Audio Signals in a Split-Supply System
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Two-Channel Microphone Input for Automotive Infotainment Systems
      3. 8.2.3 TRS Audio Interface in Single-Supply Applications
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI (Free Software Download)
        2. 11.1.1.2 TI Precision Designs
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.1.3 Start-Up Time in Single-Supply Applications

The internal supply divider of the INA165x-Q1 is constructed using two 500-kΩ resistors connected in series between the VCC and VEE pins. These resistors are matched on-chip to provide a reference voltage that is exactly one half of the power supply voltage. Noise from the power supplies and thermal noise from the resistors degrades the overall audio performance of the INA165x-Q1 if allowed to enter the signal path. Therefore, TI recommends a filter capacitor (CF) is connected to the VMID(IN) pin, as shown in Figure 46 The CF capacitor forms a low-pass filter with the internal 500-kΩ resistors. Noise above the corner frequency of this filter is passed to ground and is removed from the audio signal path. The corner frequency of the filter is shown in Equation 3:

Equation 3. INA1650-Q1 INA1651-Q1 FBD_eq_003.gif
INA1650-Q1 INA1651-Q1 AI_D002.gifFigure 46. Connect a Capacitor (CF) to the VMID(IN) Pin to Reduce Noise from the Voltage Divider
INA1650-Q1 INA1651-Q1 AI_D003.gifFigure 47. A Zener Diode (ZD1) Connected to the Positive Supply Can Decrease Start-Up Time

When power is applied to the INA165x-Q1, the filter capacitor (CF) charges through the internal 500-kΩ resistors. If the CF capacitor has a large value, the time required for VMID(OUT) to reach the final midsupply voltage may be extensive. Adding a zener diode from the VMID(IN) pin to the positive power supply (as shown in Figure 47) reduces this time. The zener voltage must be slightly greater than one half of the power supply voltage.

Using large AC-coupling capacitors increases the start-up time of the line receiver circuit in single-supply applications. When power is applied, the AC-coupling capacitors begin to charge to the midsupply voltage applied to the COM pin through a current flowing through the input resistors as shown in Figure 48. The INA165x-Q1 functions properly when the input common-mode voltage (and the capacitor voltage) is within the specified range. The time required for the input common-mode voltage to reach 98% of the final value is shown in Equation 4:

Equation 4. INA1650-Q1 INA1651-Q1 AI_eq_002.gif
INA1650-Q1 INA1651-Q1 AI_D005.gifFigure 48. AC-Coupling Capacitors Charge to the Mid-Supply Voltage Through the Input Resistors