SNCS103E November   2004  – August 2018 LMH6574

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Frequency Response vs VOUT
      2.      Frequency Response vs Gain
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
    2.     Truth Table
  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 ±5 V
    6. 6.6 Electrical Characteristics ±3.3 V
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Functional Block Diagram
    2. 7.2 Feature Description
      1. 7.2.1 Video Performance
      2. 7.2.2 Feedback Resistor Selection
      3. 7.2.3 Other Applications
      4. 7.2.4 Driving Capacitive Loads
      5. 7.2.5 ESD Protection
    3. 7.3 Device Functional Modes
      1. 7.3.1 SD vs EN
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Multiplexer Expansion
  9. 9 Power Supply Recommendations
    1. 9.1 Power Dissipation
  10. 10Layout
    1. 10.1 Layout Guidelines
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.1 SD vs EN

The LMH6574 has both shutdown and disable capability. The shutdown feature affects the entire chip, whereas the disable function only affects the output buffer. When in shutdown mode, minimal power is consumed. The shutdown function is very fast, but causes a very brief spike of about 400 mV to appear on the output. When in shutdown mode the LMH6574 consumes only 1.8 mA of supply current. For maximum input to output isolation use the shutdown function.

The EN pin only disables the output buffer which results in a substantially reduced output glitch of only 50 mV. While disabled the chip consumes 4.7 mA, considerably more than when shutdown. This is because the input buffers are still active. For minimal output glitch use the EN pin. Also, care should be taken to ensure that, while in the disabled state, the voltage differential between the active input buffer (the one selected by pins A0 and A1) and the output pin stays less than 2V. As the voltage differential increases, input to output isolation decreases. Normally this is not an issue. See Multiplexer Expansion for further details.

To reduce the output glitch when using the SD pin, switch the EN pin at least 10 ns before switching the SD pin. This can be accomplished by using an RC delay circuit between the two pins if only one control signal is available.

Logic inputs "SD" and "EN" will revert to the "High", while "A0" and "A1" will revert to the "Low" state when left floating.