Overview
The LMK00308SQ/NOPB is a 3-GHz, 8-output differential fanout buffer produced by Texas Instruments. This component is designed for high-frequency, low-jitter clock/data distribution and level translation. It features a 3:1 input multiplexer, allowing the selection of the input clock from two universal inputs or one crystal input. The selected input clock is then distributed to two banks of 4 differential outputs and one LVCMOS output. The LMK00308 is known for its high performance, versatility, and power efficiency, making it an ideal choice for replacing fixed-output buffer devices and increasing timing margin in various systems.
Key Specifications
| Parameter | Value |
|---|---|
| Package | WQFN (RTA), 40 pins |
| Operating Temperature Range | -40°C to 85°C |
| Input Frequency Range (Universal Inputs) | Up to 3.1 GHz |
| Input Frequency Range (Crystal Input) | 10 to 40 MHz |
| Differential Output Types | LVPECL, LVDS, HCSL, or Hi-Z (Selectable Per Bank) |
| LVCMOS Output | Synchronous Enable Input |
| VCC Core Supply | 3.3 V ± 5% |
| VCCO Output Supplies | 3 Independent 3.3 V/2.5 V ± 5% |
| Additive Jitter (LVPECL) at 156.25 MHz | 20 fs RMS (10 kHz to 1 MHz), 51 fs RMS (12 kHz to 20 MHz) |
| PSRR (LVPECL/LVDS) at 156.25 MHz | -65 / -76 dBc |
Key Features
- 3:1 Input Multiplexer with two universal inputs and one crystal input
- Two banks of 4 differential outputs each, configurable as LVPECL, LVDS, HCSL, or Hi-Z
- LVCMOS output with synchronous enable input for runt-pulse-free operation
- Pin-controlled configuration for output types and enable/disable functions
- High performance with low additive jitter: 20 fs RMS (10 kHz to 1 MHz) and 51 fs RMS (12 kHz to 20 MHz) for LVPECL outputs
- High PSRR: -65 / -76 dBc (LVPECL/LVDS) at 156.25 MHz
- Industrial temperature range: -40°C to +85°C
- 40-lead WQFN (6 mm × 6 mm) package
Applications
The LMK00308SQ/NOPB is suitable for various high-frequency and low-jitter applications, including:
- High-speed data centers and cloud computing infrastructure
- Telecommunication systems requiring precise clock distribution
- High-performance computing and server systems
- Networking equipment such as routers and switches
- Test and measurement equipment requiring stable clock signals
Q & A
- What is the maximum input frequency for the universal inputs of the LMK00308?
The universal inputs of the LMK00308 can operate up to 3.1 GHz.
- What types of differential outputs can be configured on the LMK00308?
The differential outputs can be configured as LVPECL, LVDS, HCSL, or Hi-Z.
- What is the operating temperature range of the LMK00308?
The operating temperature range is -40°C to 85°C.
- How many independent output supplies does the LMK00308 have?
The LMK00308 has three independent 3.3 V/2.5 V output supplies.
- What is the additive jitter performance of the LMK00308 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) for LVPECL outputs.
- Does the LMK00308 support synchronous enable for the LVCMOS output?
- What is the package type and pin count of the LMK00308?
The LMK00308 comes in a 40-lead WQFN (RTA) package.
- Can the output types of the LMK00308 be configured via pins?
- What is the PSRR of the LMK00308 at 156.25 MHz?
The PSRR is -65 / -76 dBc (LVPECL/LVDS) at 156.25 MHz.
- Is the LMK00308 suitable for high-performance computing applications?
