SLOS713J January   2011  – March 2021 OPA2835 , OPA835

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparision Table
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information: OPA835
    5. 7.5 Thermal Information: OPA2835
    6. 7.6 Electrical Characteristics: VS = 2.7 V
    7. 7.7 Electrical Characteristics: VS = 5 V
    8. 7.8 Typical Characteristics: VS = 2.7 V
    9. 7.9 Typical Characteristics: VS = 5 V
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Input Common-Mode Voltage Range
      2. 8.3.2 Output Voltage Range
      3. 8.3.3 Power-Down Operation
      4. 8.3.4 Low-Power Applications and the Effects of Resistor Values on Bandwidth
      5. 8.3.5 Driving Capacitive Loads
    4. 8.4 Device Functional Modes
      1. 8.4.1 Split-Supply Operation (±1.25 V to ±2.75 V)
      2. 8.4.2 Single-Supply Operation (2.5 V to 5.5 V)
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1  Noninverting Amplifier
      2. 9.1.2  Inverting Amplifier
      3. 9.1.3  Instrumentation Amplifier
      4. 9.1.4  Attenuators
      5. 9.1.5  Single-Ended to Differential Amplifier
      6. 9.1.6  Differential to Single-Ended Amplifier
      7. 9.1.7  Differential-to-Differential Amplifier
      8. 9.1.8  Gain Setting With OPA835 RUN Integrated Resistors
      9. 9.1.9  Pulse Application With Single-Supply
      10. 9.1.10 ADC Driver Performance
    2. 9.2 Typical Application
      1. 9.2.1 Audio Frequency Performance
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Active Filters
        1. 9.2.2.1 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Support Resources
    6. 12.6 Trademarks
    7. 12.7 Electrostatic Discharge Caution
    8. 12.8 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Detailed Design Procedure

The OPA835 device is tested in this application in a unity-gain buffer configuration. A buffer configuration is selected as the configuration maximizes the loop gain of the amplifier configuration. At higher closed-loop gains, the loop gain of the circuit reduces, which results in degraded harmonic distortion. The relationship between distortion and closed loop gain at a fixed input frequency can be seen in Figure 7-36 in Section 7.9. The test was performed under varying output-load conditions using a resistive load of 300 Ω and 100 KΩ. Figure 7-34 shows the distortion performance of the amplifier versus the output resistive load. Output loading, output swing, and closed-loop gain play a key role in determining the distortion performance of the amplifier.

Note:

The 100-pF capacitor to ground on the input helped to decouple noise pickup in the lab and improved noise performance.

The Audio Precision was configured as a single-ended output in this application circuit. In applications where a differential output is available, the OPA835 device can be configured as a differential to single-ended amplifier as shown in Figure 9-4. Power supply bypassing is critical to reject noise from the power supplies. A 2.2-μF power-supply decoupling capacitor must be placed within two inches of the device and can be shared with other op amps on the same board. A 0.1-μF decoupling capacitor must be placed as close to the power supply pins as possible, preferably within 0.1 inch. For split supply, a capacitor is required for both supplies. A 0.1-µF capacitor placed directly between the supplies is also beneficial for improving system noise performance. If the output load is heavy, from 16 Ω to 32 Ω, amplifier performance could begin to degrade. To drive such heavy loads, both channels of the OPA2835 device can be paralleled with the outputs isolated with 1-Ω resistors to reduce the loading effects.