SNAS851
December 2023
LMX1906-SP
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Pin Configuration and Functions
5
Specifications
5.1
Absolute Maximum Ratings
5.2
ESD Ratings
5.3
Recommended Operating Conditions
5.4
Thermal Information
5.5
Electrical Characteristics
5.6
Timing Requirements
5.7
Timing Diagram
5.8
Typical Characteristics
6
Detailed Description
6.1
Overview
6.1.1
Range of Dividers and Multiplier
6.2
Functional Block Diagram
6.3
Feature Description
6.3.1
Power On Reset
6.3.2
Temperature Sensor
6.3.3
Clock Outputs
6.3.3.1
Clock Output Buffers
6.3.3.2
Clock MUX
6.3.3.3
Clock Divider
6.3.3.4
Clock Multiplier
6.3.3.4.1
General Information about the Clock Multiplier
6.3.3.4.2
State Machine Clock for the Clock Multiplier
6.3.3.4.2.1
State Machine Clock
6.3.3.4.3
Calibration for the Clock Multiplier
6.3.3.4.4
Lock Detect for the Clock Multiplier
6.3.3.4.5
Watchdog Timer
6.3.4
Device Functional Modes Configurations
6.3.5
LOGICLK Output
6.3.5.1
LOGICLK Output Format
6.3.5.2
LOGICLK_DIV_PRE and LOGICLK_DIV Dividers
6.3.6
SYSREF
6.3.6.1
SYSREF Output Buffers
6.3.6.1.1
SYSREF Output Buffers for Main Clocks (SYSREFOUT)
6.3.6.1.2
SYSREF Output Buffer for LOGICLK
6.3.6.2
SYSREF Frequency and Delay Generation
6.3.6.3
SYSREFREQ pins and SYSREFREQ_FORCE Field
6.3.6.3.1
SYSREFREQ Pins Common-Mode Voltage
6.3.6.3.2
SYSREFREQ Windowing Feature
6.3.6.3.2.1
General Procedure Flowchart for SYSREF Windowing Operation
6.3.6.3.2.2
SYSREFREQ Repeater Mode With Delay Gen (Retime)
6.3.6.3.2.3
Other Pointers With SYSREF Windowing
6.3.6.3.2.4
For Glitch-Free Output
6.3.6.3.2.5
If Using SYNC Feature
6.3.6.3.3
SYNC Feature
6.3.7
Pin Mode Control
6.3.7.1
Chip Enable (CE)
6.3.7.2
Output Channel Control
6.3.7.3
Logic Output Control
6.3.7.4
SYSREF Output Control
6.3.7.5
Device Mode Selection
6.3.7.6
Divider or Multiplier Value Selection
6.3.7.7
Calibration Control Pin
6.3.7.8
Output Power Control
7
Application and Implementation
7.1
Applications Information
7.1.1
SYSREFREQ Input Configuration
7.1.2
Treatment of Unused Pins
7.1.3
Current Consumption
7.2
Typical Applications
7.2.1
Local Oscillator Distribution Application
7.2.1.1
Design Requirements
7.2.1.2
Detailed Design Procedure
7.2.1.3
Application Plots
7.2.2
JESD204B/C Clock Distribution Application
7.3
Power Supply Recommendations
7.3.1
Power-Up Timing
7.4
Layout
7.4.1
Layout Guidelines
7.4.2
Layout Example
7.5
Register Map
7.5.1
Device Registers
8
Device and Documentation Support
8.1
Device Support
8.2
Receiving Notification of Documentation Updates
8.3
Support Resources
8.4
Trademarks
8.5
Electrostatic Discharge Caution
8.6
Glossary
9
Revision History
10
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
PAP|64
MPQF071C
Thermal pad, mechanical data (Package|Pins)
PAP|64
PPTD060M
Orderable Information
snas851_oa
snas851_pm
1
Features
SMD #5962-23202
Total ionizing dose 100 krad (ELDRS-free)
Single event latch-up (SEL) immune up to 87 MeV - cm
2
/mg
Single event functional interrupt (SEFI) immune up to 87 MeV - cm
2
/mg
Clock buffer for 300-MHz to 15-GHz frequency
Ultra-Low Noise
Noise floor of –159 dBc/Hz at 6-GHz output
36-fs additive jitter (100 Hz to f
CLK
) at 6-GHz output
5-fs additive jitter (100 Hz - 100 MHz)
4 high-frequency clocks with corresponding SYSREF outputs
Shared divide by 1 (Buffer), 2, 3, 4, 5, 6, 7, and 8
Shared programmable multiplier x2, x3, and x4
Support pin mode options to configure the device without SPI
LOGICLK output with corresponding SYSREF output
On separate divide bank
1, 2, 4 pre-divider
1 (bypass), 2, …, 1023 post divider
8 programmable output power levels
Synchronized SYSREF clock outputs
508 delay step adjustments of less than 2.5 ps each at 12.8 GHz
Generator and repeater modes
Windowing feature for SYSREFREQ pins to optimize timing
SYNC feature to all divides and multiple devices
2.5-V operating voltage
–55ºC to +125ºC operating temperature