SCAS928D May   2012  – April 2019 CDCUN1208LP

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Pin Configuration Overview
  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  Digital Input Electrical Characteristics – OE (SCL), INSEL, ITTP, OTTP, Divide (SDA/MOSI), ERC(ADDR/CS), Mode
    6. 6.6  Universal Input (IN1, IN2) Characteristics
    7. 6.7  Clock Output Buffer Characteristics (Output Mode = LVDS)
    8. 6.8  Clock Output Buffer Characteristics (Output Mode = HCSL)
    9. 6.9  Clock Output Buffer Electrical Characteristics (Output Mode = LVCMOS)
    10. 6.10 Clock Output Buffer Electrical Characteristics (Output Mode = LVCMOS) (Continued)
    11. 6.11 Clock Output Buffer Electrical Characteristics (Output Mode = LVCMOS) (Continued)
    12. 6.12 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Test Configurations
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Device Control Using Configuration Pins
        1. 8.3.1.1 Configuration of Output Type (OTTP)
        2. 8.3.1.2 Configuration of Edge Rate Control (ERC)
        3. 8.3.1.3 Control of Output Enable (OE)
      2. 8.3.2 Input Ports (IN1, IN2)
        1. 8.3.2.1 Configuration of the Input Type (ITTP)
        2. 8.3.2.2 Configuration of the IN2 Divider (INDIV)
      3. 8.3.3 Smart Input Multiplexer (INMUX)
        1. 8.3.3.1 Pin Configuration of the Smart Input Multiplexer (INMUX)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Control Using the Host Interface
        1. 8.4.1.1 OE and INSEL in Host Configuration Mode
    5. 8.5 Programming
      1. 8.5.1 Host Interface Hardware Information
        1. 8.5.1.1 SPI Communication
          1. 8.5.1.1.1 CDCUN1208LP SPI Addressing
          2. 8.5.1.1.2 Writing to the CDCUN1208LP
          3. 8.5.1.1.3 Reading From the CDCUN1208LP
          4. 8.5.1.1.4 Block Write/Read Operation
        2. 8.5.1.2 I2C Communication
          1. 8.5.1.2.1 Message Transmission
            1. 8.5.1.2.1.1 Data and Address Bits
            2. 8.5.1.2.1.2 Special Symbols – Start (S) and Stop (P)
            3. 8.5.1.2.1.3 Special Symbols – Acknowledge (ACK)
            4. 8.5.1.2.1.4 Generic Message Frame
            5. 8.5.1.2.1.5 CDCUN1208LP Message Format
            6. 8.5.1.2.1.6 CDCUN1208LP Device Addressing (I2C Address)
            7. 8.5.1.2.1.7 CDCUN1208LP Device Addressing (Register Address)
          2. 8.5.1.2.2 I2C Master and Slave Handshaking
          3. 8.5.1.2.3 Block Read/Write
          4. 8.5.1.2.4 I2C Timing
    6. 8.6 Register Maps
      1. 8.6.1 Device Registers
        1. 8.6.1.1 Device Registers: Register 00-07
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 PCI Express Applications
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
    3. 9.3 Systems Examples
  10. 10Power Supply Recommendations
    1. 10.1 CDCUN1208LP Power Consumption
    2. 10.2 Device Power Supply Connections and Sequencing
    3. 10.3 Device Inputs (IN1, IN2)
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

10.2 Device Power Supply Connections and Sequencing

VDD (pin 5) is the core power supply of the device while VDDOx (pins 11, 14, 22, and 27) provide power for the output sections. The core supply must be present either before the application of the output power supplies or be present simultaneously. Applying an output power supply voltage on any of the VDDOx pins prior to the application of power to the core supply pin potentially results in improper device operation.

VDDO2 (pin 14) and VDDO4 (pin 27) provide power for OUT1/OUT2 and OUT7/OUT8, respectively. Additionally, these pins provide power to integrated voltage regulators that condition power for two banks of outputs. For example, the regulator associated with OUT1–OUT4 receives power from the VDDO2 pin. Consequently, if the application requires one or two outputs from a bank of four, then the application must use OUT3/OUT4 and apply power through VDDO2 (2). Likewise, the regulator that conditions power for OUT5–OUT8 receives power from VDDO4 (pin 27). If the application uses subset of OUT5–OUT8, then OUT7/OUT8 must be used. For example, if the application uses 6 of the 8 output channels, then VDDO1, VDDO2, and VDDO4 (along with OUT1–OUT4, and OUT7–OUT8) must be used. If the application requires the use of 7 of the 8 output channels, the VDDO1–VDDO4 are used, and OUT1–OUT7 or OUT1–OUT6 and OUT8 could be used.

2. If OUT1 or OUT2 are used and VDDO1 is powered but not VDDO2, the CDCUN1208LP will not function properly. Likewise, if OUT5 or OUT6 are used and VDDO3 is powered but not VDDO4, then the device will not function properly either.