Clock/Timing - Clock Buffers, Drivers

Part Number	Description / PDF	Quantity
PI49FCT32805QE Zetex Semiconductors (Diodes Inc.)	IC CLK BUFFER 1:5 133MHZ 20QSOP	893
PL123-05NSC Roving Networks / Microchip Technology	IC CLK BUFFER 1:5 134MHZ 8SOP	1169
83948AYILF Renesas Electronics America	IC CLK BUFFER 2:12 250MHZ 32TQFP	5
SI5330L-B00229-GMR Silicon Labs	IC CLK BUFFER 1:4 LVDS 24QFN	2234
SY58608UMG-TR Roving Networks / Microchip Technology	IC CLK BUFFER 1:2 3GHZ 16MLF	1843
W163-15GT Rochester Electronics	PLL BASED CLOCK DRIVER	4785
5PB1203NTGK Renesas Electronics America	DFN 2.00X2.00X0.75 MM, 0.40MM PI	0
49FCT3805QG8 Renesas Electronics America	IC CLOCK BUFFER 1:5 20QSOP	2001
LMK00301ARHSR Texas Instruments	LMK00301ARHSR	0
CDCLVP110VFG4 Texas Instruments	IC CLK BUFFER 2:10 3.5GHZ 32LQFP	0
ZL40234LDG1 Roving Networks / Microchip Technology	LOW SKEW, LOW ADDITIVE JITTER 3	15
CDCLVD110AVF Texas Instruments	IC CLK BUFFER 2:10 1.1GHZ 32LQFP	237
MC100LVE111FNG Sanyo Semiconductor/ON Semiconductor	IC CLK BUFFER 1:9 1.5GHZ 28PLCC	0
PI6C48545LEX Zetex Semiconductors (Diodes Inc.)	IC CLOCK BUFFER MUX 2:4 20TSSOP	0
MC100LVEP11DTR2G	LOW SKEW CLOCK DRIVER, 100LVE SE	4220
CY23FP12OI Rochester Electronics	PLL BASED CLOCK DRIVER	2821
8SLVD1208-33NBGI8 Renesas Electronics America	IC CLK BUFFER 1:8 2GHZ 28VFQFN	0
MC10EL15DR2G	LOW SKEW CLOCK DRIVER, 10EL SERI	8533
LMK00725PWR Texas Instruments	DIFFERENTIAL-TO-3.3V LVPECL FANO	0
MC100EP11MNR4G	LOW SKEW CLOCK DRIVER, 10EP SERI	48979

Clock/Timing - Clock Buffers, Drivers

1. Overview

Clock buffers and drivers are integrated circuits (ICs) designed to distribute clock signals in electronic systems. They amplify, condition, and route timing signals to multiple destinations while minimizing skew, jitter, and signal degradation. These components are critical in synchronizing operations across processors, memory modules, communication interfaces, and other timing-sensitive circuits. Their importance spans industries such as telecommunications, automotive, and high-performance computing.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Clock Buffers	Single-input, multiple-output devices with low phase noise and skew	CPU clock distribution, FPGA systems
Clock Drivers	High-drive capability for fan-out applications	Networking switches, server motherboards
Differential Clock Buffers	Supports LVDS, HCSL, and CML signal types	High-speed ADC/DAC systems, RF transceivers
Programmable Clock Buffers	Configurable output frequency/division ratios	Industrial automation, test equipment

3. Structure and Composition

Clock buffers/drivers typically consist of:

Input receivers (single-ended or differential)
Internal amplification stages
Output drivers with controlled impedance
Power supply decoupling structures
Thermal management pads (in QFN/SSOP packages)

They are fabricated using CMOS, Bipolar, or SiGe processes to optimize speed and noise performance.

4. Key Technical Specifications

Parameter	Description	Importance
Max Operating Frequency	Up to 1.2 GHz (CMOS), 3.2 GHz (SiGe)	Determines application suitability for high-speed systems
Additive Phase Jitter	0.05 ps RMS to 1 ps RMS	Impacts timing precision in data converters
Propagation Delay	50 ps to 5 ns	Critical in synchronized multi-channel systems
Output Voltage Levels	LVCMOS, LVDS, HSTL, etc.	Ensures compatibility with downstream circuits
Supply Voltage	1.8V to 5V	Affects power consumption and integration

5. Application Areas

Telecommunications: 5G base stations, optical transceivers
Computing: Servers, workstations, high-end PCs
Industrial: PLCs, motor controllers, test instruments
Automotive: ADAS clock synchronization, infotainment systems

Case Study: In 5G massive MIMO systems, low-jitter clock drivers ensure phase coherence across 64+ antenna elements.

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Specifications
TI (Texas Instruments)	CDCE62005	3.2 GHz LVDS driver, 0.1 ps RMS jitter
Analog Devices	ADCLK846	16-output clock buffer, 1.6 GHz bandwidth
STMicroelectronics	DF1610S	1.8V/3.3V dual supply buffer, 8 outputs
ON Semiconductor	MC100EP195	Differential ECL buffer, 2.5 GHz operation

7. Selection Recommendations

Key considerations:

Match output type to receiver requirements (LVDS/CML/LVCMOS)
Calculate required fan-out capacity with voltage margin
Specify jitter budget (e.g., <0.3 ps RMS for 10 Gbps SerDes)
Consider temperature stability (-40 C to +125 C automotive grade)
Optimize package size vs. thermal dissipation needs

8. Industry Trends

Future developments include:

Sub-100 fs jitter performance using advanced CMOS processes
Integration with PLL/VCO for clock generation
Multi-die packaging for hybrid signal conditioning
Energy-efficient designs for battery-powered IoT devices
Automotive-grade ICs with AEC-Q100 qualification