SNOSC72F June   2012  – February 2015 LMH6881

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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
      1. 6.6.1 Single-Ended Input
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 Digital Control of the Gain and Power-Down Pins
        1. 7.5.1.1 Parallel Interface
        2. 7.5.1.2 SPI-Compatible Serial Interface
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Input Characteristics
      2. 8.1.2 Output Characteristics
      3. 8.1.3 Interfacing to an ADC
        1. 8.1.3.1 ADC Noise Filter
        2. 8.1.3.2 AC Coupling to ADC
        3. 8.1.3.3 DC Coupling to ADC
      4. 8.1.4 Figure of Merit: Dynamic Range Figure
    2. 8.2 Typical Applications
      1. 8.2.1 LMH6881 Typical Application
        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 LMH6881 Used as Twisted-Pair Cable Driver
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Uncontrolled Impedance Traces
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

9 Power Supply Recommendations

The LMH6881 was designed to be operated on 5-V power supplies. The voltage range for VCC is from 4.75 V to 5.25 V. Power-supply accuracy of 5% or better is advised. When operated on a board with high-speed digital signals it is important to provide isolation between digital signal noise and the analog input pins. The SP16160CH1RB reference board provides an example of good board layout.

The power supply pins are 19, 20, 23 and 24. Each supply pin should be decoupled with a low-inductance, surface-mount ceramic capacitor of approximately 10 nF as close to the device as possible. When vias are used to connect the bypass capacitors to a ground plane the vias should be configured for minimal parasitic inductance. One method of reducing via inductance is to use multiple vias. For broadband systems two capacitors per supply pin are advised.

To avoid undesirable signal transients the LMH6881 should not be powered on with large inputs signals present. Careful planning of system power on sequencing is especially important to avoid damage to ADC inputs when an ADC is used in the application.