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

7.3.1.2.2 CDS Mode CLAMP/SAMPLE Adjust

In CDS mode, the LM98640QML-SP utilizes two input networks, alternating between them every pixel, to increase throughput speeds. Because of this, there are two sets of CLAMP and SAMPLE windows defined in Table 8, one for even pixels and one for odd. Sample Start and Sample End Registers (0x22,0x23) along with the Clamp Start and Clamp End Registers (0x20,0x21) control both the even and odd CLAMP and SAMPLE pulses. To adjust the CLAMP and SAMPLE pulses, first send the CLAMPODD and SAMPLEODD signals to the DTM pins by writing 10 to bits[4:3] of the Clock Monitor Register (0x09). This will allow the user to observe the CLAMPODD and SAMPLEODD pulses on pins DTM0 and DTM1 along with the image sensor output using an oscilloscope. The CLAMP and SAMPLE pulses will only be shown for every other pixel because of the even odd architecture, but the positions of the even CLAMP and SAMPLE pulses will be identically defined to that of the odd CLAMP and SAMPLE; however, odd and even path mismatch could result in a slightly different position of the pulses. Then, using the Clamp Start/End and Sample Start/End registers, adjust the positions of the CLAMP and SAMPLE pulses to align them over the Reference and Video Levels of the input signal. To allow for settling and to reduce noise, the CLAMP and SAMPLE pulses should be made as wide as possible and placed near the far edge of their respective input levels.

The following figure shows some examples of input CCD waveforms and placement of the CLAMP and SAMPLE positions for each. Ideally the CCD output would line up directly with the input clock at the AFE inputs, but due to trace delays in the system the CCD output is delayed relative to the input clock. In the Delayed CCD waveform the Sample Start/End Register values are lower than the Clamp Start/End Register Values. In this situation the sample pulse is not generated until the next clock period, which allows it to be correctly placed in the Video Level of the input signal. Notice that edge zero of the internal clock does not line up with the rising edge of the input clock. This is due to internal delays of the clock signals. The amount of delay can be calculated from operating frequency using the following formula: tDCLK = 6.0 ns + 3 / 64 × TINCLK

LM98640QML-SP 30064774.gifFigure 16. CDS Mode CLAMP/SAMPLE Adjust