SNAS461G May   2010  – November 2018 LM98640QML-SP

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  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 Quality Conformance Inspection
    6. 6.6 LM98640QML-SP Electrical Characteristics
    7. 6.7 AC Timing Specifications
    8. 6.8 Typical Performance Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Input Sampling Modes
        1. 7.3.1.1 Sample & Hold Mode
          1. 7.3.1.1.1 Sample & Hold Mode CLAMP/SAMPLE Adjust
        2. 7.3.1.2 CDS Mode
          1. 7.3.1.2.1 CDS Mode Bimodal Offset
          2. 7.3.1.2.2 CDS Mode CLAMP/SAMPLE Adjust
      2. 7.3.2 Input Bias and Clamping
        1. 7.3.2.1 Sample and Hold Mode Biasing
        2. 7.3.2.2 CDS Mode Biasing
        3. 7.3.2.3 VCLP DAC
      3. 7.3.3 Programmable Gain
        1. 7.3.3.1 CDS/SH Stage Gain
        2. 7.3.3.2 PGA Gain Plots
      4. 7.3.4 Programmable Analog Offset Correction
      5. 7.3.5 Analog to Digital Converter
      6. 7.3.6 LVDS Output
        1. 7.3.6.1 LVDS Output Voltage
        2. 7.3.6.2 LVDS Output Modes
        3. 7.3.6.3 TXFRM Output
          1. 7.3.6.3.1 Output Mode 1 - Dual Lane
          2. 7.3.6.3.2 Output Mode 2 - Quad Lane
      7. 7.3.7 Clock Receiver
      8. 7.3.8 Power Trimming
    4. 7.4 Device Functional Mode
      1. 7.4.1 Powerdown Modes
      2. 7.4.2 LVDS Test Modes
        1. 7.4.2.1 Test Mode 0 - Fixed Pattern
        2. 7.4.2.2 Test Mode 1 - Horizontal Gradient
        3. 7.4.2.3 Test Mode 2 - Vertical Gradient
        4. 7.4.2.4 Test Mode 3 - Lattice Pattern
        5. 7.4.2.5 Test Mode 4 - Stripe Pattern
        6. 7.4.2.6 Test Mode 5 - LVDS Test Pattern (Synchronous)
        7. 7.4.2.7 Test Mode 6 - LVDS Test Pattern (Asynchronous)
        8. 7.4.2.8 Pseudo Random Number Mode
    5. 7.5 Programming
      1. 7.5.1 Serial Interface
      2. 7.5.2 Writing to the Serial Registers
      3. 7.5.3 Reading the Serial Registers
      4. 7.5.4 Serial Interface Timing Details
    6. 7.6 Register Maps
      1. 7.6.1 Register Definitions
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Total Ionizing Dose
      2. 8.1.2 Single Event Latch-Up and Functional Interrupt
      3. 8.1.3 Single Event Effects
    2. 8.2 Typical Application
      1. 8.2.1 Sample/Hold Mode
    3. 8.3 Initialization Set Up
  9. 9 Layout
    1. 9.1 Layout Guidelines
      1. 9.1.1 Power Planes
      2. 9.1.2 Bypass Capacitors
      3. 9.1.3 Ground Plane
      4. 9.1.4 Thermal Management
  10. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 Evaluation Board
        2. 10.1.1.2 Register Programming Software
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Community Resources
    4. 10.4 Export Control Notice
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  11. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Engineering Samples

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • NBB|68
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.8 Power Trimming

The LM98640QML-SP provides an adaptive power scaling feature that allows the user to optimize power consumption based on the maximum operating frequency and the maximum amount of gain required. The power scaling mode is selectable through the PGA Power Trimming and ADC Power Trimming registers (0x02,0x03). The settings in these registers are common for both channels PGA and ADC. Using these registers the user can control the current of the two stages of the PGA, and the current for the two levels of the ADC. The following table provides a set of baseline configurations for various operating frequencies and gain ranges.

These configurations should be treated as baseline values and can be tuned to your specific application.

OPERATING FREQUENCY 1-4x MAX PGA GAIN 1-8x MAX PGA GAIN
5 - 15 MSPS PGA Power Trimming = 0x00
ADC Power Trimming = 0x00		 PGA Power Trimming = 0x01
ADC Power Trimming = 0x00
15 - 25 MSPS PGA Power Trimming = 0x01
ADC Power Trimming = 0x00		 PGA Power Trimming = 0x09
ADC Power Trimming = 0x00
25 - 40 MSPS PGA Power Trimming = 0x01
ADC Power Trimming = 0x08		 PGA Power Trimming = 0x09
ADC Power Trimming = 0x08