Overview
The LMK00306SQE/NOPB, produced by Texas Instruments (previously National Semiconductor), is a 3-GHz, 6-output differential fanout buffer designed for high-frequency, low-jitter clock/data distribution and level translation. This device allows the input clock to be selected from two universal inputs or one crystal input, which is then distributed to two banks of three differential outputs and one LVCMOS output. The LMK00306 operates from a 3.3 V core supply and three independent 3.3 V/2.5 V output supplies, making it highly versatile and power-efficient. It is ideal for replacing fixed-output buffer devices and increasing timing margin in various systems.
Key Specifications
| Parameter | Value |
|---|---|
| Package | 36-lead WQFN (6 mm × 6 mm) |
| Operating Temperature Range | -40°C to +85°C |
| Input Types | CML, HCSL, HSTL, LVDS, LVPECL, SSTL, Crystal |
| Output Types | HCSL, LVCMOS, LVDS, LVPECL |
| Maximum Frequency | 3.1 GHz |
| VCC Core Supply | 3.3 V ± 5% |
| VCCO Output Supplies | 3.3 V/2.5 V ± 5% (3 independent supplies) |
| LVPECL Additive Jitter | 20 fs RMS (10 kHz to 1 MHz), 51 fs RMS (12 kHz to 20 MHz) at 156.25 MHz |
| PSRR | -65 / -76 dBc (LVPECL/LVDS) at 156.25 MHz |
Key Features
- 3:1 Input Multiplexer with two universal inputs operating up to 3.1 GHz and one crystal input accepting 10 to 40 MHz clocks.
- Two banks with three differential outputs each, configurable as LVPECL, LVDS, or HCSL drivers, or disabled.
- LVCMOS output with synchronous enable input for runt-pulse-free operation.
- Pin-controlled configuration for output bank settings.
- High PSRR: -65 / -76 dBc (LVPECL/LVDS) at 156.25 MHz.
- Ultra-low additive jitter: 20 fs RMS (10 kHz to 1 MHz), 51 fs RMS (12 kHz to 20 MHz) at 156.25 MHz.
Applications
- Clock distribution and level translation for ADCs, DACs, multi-gigabit Ethernet, XAUI, Fibre Channel, SATA/SAS, SONET/SDH, CPRI, and high-frequency backplanes.
- Switches, routers, line cards, and timing cards.
- Servers, computing, and PCI Express (PCIe 3.0).
- Remote radio units and baseband units.
Q & A
- What is the maximum operating frequency of the LMK00306?
The LMK00306 operates up to 3.1 GHz.
- What types of input clocks can the LMK00306 accept?
The device accepts CML, HCSL, HSTL, LVDS, LVPECL, SSTL, and crystal inputs.
- How many differential output banks does the LMK00306 have?
The device has two banks with three differential outputs each.
- What are the configurable output types for each bank?
Each bank can be configured as LVPECL, LVDS, or HCSL drivers, or disabled.
- What is the voltage range for the VCC core supply and VCCO output supplies?
The VCC core supply is 3.3 V ± 5%, and the VCCO output supplies are 3.3 V/2.5 V ± 5%.
- What is the operating temperature range of the LMK00306?
The operating temperature range is -40°C to +85°C.
- What is the package type and size of the LMK00306?
The device is packaged in a 36-lead WQFN (6 mm × 6 mm).
- What is the additive jitter performance of the LMK00306 at 156.25 MHz?
The additive jitter is 20 fs RMS (10 kHz to 1 MHz) and 51 fs RMS (12 kHz to 20 MHz).
- What is the PSRR of the LMK00306 at 156.25 MHz?
The PSRR is -65 / -76 dBc (LVPECL/LVDS) at 156.25 MHz.
- What types of applications is the LMK00306 suitable for?
The device is suitable for clock distribution and level translation in various high-frequency applications, including ADCs, DACs, multi-gigabit Ethernet, and more.
