SCAS891A February   2010  – May 2025 CDCE949-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Thermal Resistance Characteristics
    4. 5.4  Recommended Operating Conditions
    5. 5.5  Recommended Crystal/VCXO Specifications
    6. 5.6  EEPROM Specification
    7. 5.7  Electrical Characteristics
    8. 5.8  Timing Requirements
      1. 5.8.1 CLK_IN Timing Requirements
      2. 5.8.2 SDA/SCL Timing Requirements
    9. 5.9  Timing Diagrams
      1. 5.9.1 Timing Diagram for the SDA/SCL Serial Control Interface
    10. 5.10 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Control Terminal Configuration
      2. 7.3.2 Default Device Setting
      3. 7.3.3 SDA/SCL Serial Interface
      4. 7.3.4 Data Protocol
      5. 7.3.5 PLL Multiplier/Divider Definition
    4. 7.4 Device Functional Modes
      1. 7.4.1 SDA/SCL Hardware Interface
    5. 7.5 Programming
      1. 7.5.1 Generic Programming Sequence
      2. 7.5.2 Byte Write Programming Sequence
      3. 7.5.3 Byte Read Programming Sequence
      4. 7.5.4 Block Write Programming Sequence
      5. 7.5.5 Block Read Programming Sequence
  9. 8 Register Maps
    1. 8.1 SDA and SCL Registers
    2. 8.2 Configuration Registers
      1. 8.2.1 Generic Configuration Register
      2. 8.2.2 PLL1 Configuration Register
      3. 8.2.3 PLL2 Configuration Register
      4. 8.2.4 PLL3 Configuration Register
      5. 8.2.5 PLL4 Configuration Register
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Spread Spectrum Clock (SSC)
        2. 9.2.2.2 PLL Frequency Planning
        3. 9.2.2.3 Crystal Oscillator Start-Up
        4. 9.2.2.4 Frequency Adjustment With Crystal Oscillator Pulling
        5. 9.2.2.5 Unused Inputs and Outputs
        6. 9.2.2.6 Switching Between XO and VCXO Mode
      3. 9.2.3 Application Performance Plots
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

8.2.2 PLL1 Configuration Register

Table 8-4 PLL1 Configuration Register
OFFSET(1) Bit(2) Acronym Default(3) DESCRIPTION
10h 7:5 SSC1_7 [2:0] 000b SSC1: PLL1 SSC Selection (Modulation Amount)(4)
4:2 SSC1_6 [2:0] 000b Down
000 (off)
001 – 0.25%
010 – 0.5%
011 – 0.75%
100 – 1.0%
101 – 1.25%
110 – 1.5%
111 – 2.0%		 Center
000 (off)
001 ± 0.25%
010 ± 0.5%
011 ± 0.75%
100 ± 1.0%
101 ± 1.25%
110 ± 1.5%
111 ± 2.0%
1:0 SSC1_5 [2:1] 000b
11h 7 SSC1_5 [0]
6:4 SSC1_4 [2:0] 000b
3:1 SSC1_3 [2:0] 000b
0 SSC1_2 [2] 000b
12h 7:6 SSC1_2 [1:0]
5:3 SSC1_1 [2:0] 000b
2:0 SSC1_0 [2:0] 000b
13h 7 FS1_7 0b FS1_x: PLL1 Frequency Selection(4)
6 FS1_6 0b 0 – fVCO1_0 (predefined by PLL1_0 – Multiplier/Divider value)
1 – fVCO1_1 (predefined by PLL1_1 – Multiplier/Divider value)
5 FS1_5 0b
4 FS1_4 0b
3 FS1_3 0b
2 FS1_2 0b
1 FS1_1 0b
0 FS1_0 0b
14h 7 MUX1 1b PLL1 Multiplexer: 0 – PLL1
1 – PLL1 Bypass (PLL1 is in power down)
6 M2 1b Output Y2 Multiplexer: 0 – Pdiv1
1 – Pdiv2
5:4 M3 10b Output Y3 Multiplexer: 00 – Pdiv1-Divider
01 – Pdiv2-Divider
10 – Pdiv3-Divider
11 – reserved
3:2 Y2Y3_ST1 11b Y2, Y3-State0/1definition: 00 – Y2/Y3 disabled to 3-State (PLL1 is in power down)
01 – Y2/Y3 disabled to 3-State (PLL1 on)
10–Y2/Y3 disabled to low (PLL1 on)
11 – Y2/Y3 enabled (normal operation, PLL1 on)
1:0 Y2Y3_ST0 01b
15h 7 Y2Y3_7 0b Y2Y3_x Output State Selection(4)
6 Y2Y3_6 0b 0 – state0 (predefined by Y2Y3_ST0)
1 – state1 (predefined by Y2Y3_ST1)
5 Y2Y3_5 0b
4 Y2Y3_4 0b
3 Y2Y3_3 0b
2 Y2Y3_2 0b
1 Y2Y3_1 1b
0 Y2Y3_0 0b
16h 7 SSC1DC 0b PLL1 SSC down/center selection: 0 – down
1 – center
6:0 Pdiv2 01h 7-Bit Y2-Output-Divider Pdiv2: 0 – reset and stand-by
1-to-127 – divider value
17h 7 — 0b Reserved – do not write others than 0
6:0 Pdiv3 01h 7-Bit Y3-Output-Divider Pdiv3: 0 – reset and stand-by
1-to-127 – divider value
18h 7:0 PLL1_0N [11:4 004h PLL1_0: 30-Bit Multiplier/Divider value for frequency fVCO1_0
(for more information see PLL Multiplier/Divider Definition)
19h 7:4 PLL1_0N [3:0]
3:0 PLL1_0R [8:5] 000h
1Ah 7:3 PLL1_0R[4:0]
2:0 PLL1_0Q [5:3] 10h
1Bh 7:5 PLL1_0Q [2:0]
4:2 PLL1_0P [2:0] 010b
1:0 VCO1_0_RANGE 00b fVCO1_0 range selection: 00 – fVCO1_0 < 125MHz
01 – 125MHz ≤ fVCO1_0 < 150MHz
10 – 150MHz ≤ fVCO1_0 < 175MHz
11 – fVCO1_0 ≥ 175MHz
1Ch 7:0 PLL1_1N [11:4] 004h PLL1_1: 30-Bit Multiplier/Divider value for frequency fVCO1_1
(for more information see paragraph PLL Multiplier/Divider Definition)
1Dh 7:4 PLL1_1N [3:0]
3:0 PLL1_1R [8:5] 000h
1Eh 7:3 PLL1_1R[4:0]
2:0 PLL1_1Q [5:3] 10h
1Fh 7:5 PLL1_1Q [2:0]
4:2 PLL1_1P [2:0] 010b
1:0 VCO1_1_RANGE 00b fVCO1_1 range selection: 00 – fVCO1_1 < 125MHz
01 – 125MHz ≤ fVCO1_1 < 150MHz
10 – 150MHz ≤ fVCO1_1 < 175MHz
11 – fVCO1_1 ≥ 175MHz
(1) Writing data beyond 50h can adversely affect device function.
(2) All data is transferred MSB-first.
(3) Unless a custom setting is used
(4) The user can pre-define up to eight different control settings. In normal device operation, these settings can be selected by the external control pins, S0, S1, and S2.