Clock/Timing - Clock Generators, PLLs, Frequency Synthesizers

Image	Part Number	Description / PDF	Quantity	Rfq
	LMX2370TM Texas Instruments	IC FREQ SYNTH DL 2.5GHZ 20TSSOP	0
	LMX2312USLDX/NOPB Texas Instruments	IC FREQ SYNTH 1.2GHZ 20LAMTCSP	0
	CDC2509PWRG4 Texas Instruments	IC 3.3V PLL CLK-DRVR 24-TSSOP	0
	LMX2330UTM Texas Instruments	IC FREQ SYNTHESIZER DUAL 20TSSOP	0
	CDC421125RGERG4 Texas Instruments	IC CLOCK GENERATOR 125MHZ 24-QFN	0
	CDC421106RGER Texas Instruments	IC CLOCK GENERATOR 100MHZ 24-QFN	0
	LMX2364TM/NOPB Texas Instruments	IC FREQ SYNTH 2.6GHZ 24TSSOP	0
	CDC2586PAHG4 Texas Instruments	IC 3.3V PLL CLK-DRVR 52-TQFP	0
	LMX2347SLBX/NOPB Texas Instruments	IC FREQ SYNTH 2.5GHZ 16LAMCSP	0
	LMX1511TMX Texas Instruments	IC FREQ SYNTHESZR 1.1GHZ 20TSSOP	0
	CDC7005RGZRG4 Texas Instruments	IC CLK SYNC/JITTER CLEANR 48VQFN	0
	LMX2332LTM/NOPB Texas Instruments	IC FREQ SYNTHESIZER DUAL 20TSSOP	0
	CDC930DLG4 Texas Instruments	IC DIFF CLOCK SYNTH/DRVR 56-SSOP	0
	LMX2315TMX Texas Instruments	IC FREQ SYNTH 2.5GHZ 20-TSSOP	0
	LMX1601TMX/NOPB Texas Instruments	IC FREQ SYNTHESIZER DUAL 16TSSOP	0
	CDCV850IDGGRG4 Texas Instruments	IC PLL CLOCK DRVR 2.5V 48TSSOP	0
	LMX2320TMX Texas Instruments	IC FREQ SYNTH 2.0GHZ 20-TSSOP	0
	CDC421106RGERG4 Texas Instruments	IC CLOCK GENERATOR 100MHZ 24-QFN	0
	LMX1602TM/NOPB Texas Instruments	IC PLL DUAL 1.1GHZ 16TSSOP	0
	LMX2330LTMX/NOPB Texas Instruments	IC FREQ SYNTH DUAL 20-TSSOP	0

Clock/Timing - Clock Generators, PLLs, Frequency Synthesizers

1. Overview

Clock and timing ICs are semiconductor devices that generate, regulate, and distribute timing signals in electronic systems. Key components include Clock Generators (produce stable clock signals), Phase-Locked Loops (PLLs, synchronize signals with phase alignment), and Frequency Synthesizers (generate precise frequencies from reference signals). These devices ensure synchronization across components in modern electronics, enabling reliable operation in communication systems, computing devices, and industrial equipment.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Clock Generators	Produce fixed or programmable clock signals with low jitter	Microprocessors, FPGAs, networking equipment
PLLs	Align output signal phase with reference input, enable frequency multiplication	Wireless transceivers, data recovery circuits
Frequency Synthesizers	Generate multiple frequencies from single reference with high precision	5G base stations, satellite communication systems

3. Structure and Components

Typical clock ICs feature: 1) Crystal oscillator interface for reference signal input; 2) Internal voltage-controlled oscillator (VCO); 3) Phase detector and loop filter (PLL components); 4) Programmable dividers; 5) Output buffers. Advanced packages include QFN (4x4mm to 8x8mm) and TSSOP with 8-48 pins. Integration levels vary from single-channel devices to multi-output clock generators with integrated EEPROM.

4. Key Technical Specifications

Parameter	Typical Range	Importance
Frequency Range	1 kHz - 3.6 GHz	Determines application compatibility
Phase Noise	-150 to -120 dBc/Hz	Impacts signal integrity
Jitter (RMS)	50 fs - 1 ps	Critical for high-speed systems
Power Consumption	10-300 mA	Affects thermal design
Temperature Stability	20-100 ppm	Ensures reliability in harsh environments

5. Application Fields

Telecommunications: 5G NR base stations, optical transceivers
Computing: Server motherboards, PCIe clocks
Industrial: Precision test equipment, motor control systems
Automotive: ADAS sensors, infotainment systems
Medical: MRI imaging systems, patient monitoring devices

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
TI (Texas Instruments)	LMX2594	15-GHz wideband PLL with integrated VCO
Analog Devices	AD9548	4-channel clock generator with 0.1 ppb accuracy
STMicroelectronics	CLK2692	Programmable 2-output synthesizer for automotive
Microchip	ZL30264	High-performance network synchronizer

7. Selection Guidelines

Key selection criteria: 1) Required output frequency and voltage levels; 2) Acceptable phase noise/jitter specifications; 3) Number of required outputs; 4) Operating temperature range; 5) Power budget constraints; 6) Integration level (e.g., single-chip vs. discrete VCO solutions). For wireless applications, prioritize low phase noise. For portable devices, emphasize power efficiency.

8. Industry Trends

Future developments include: 1) Higher integration with on-chip EEPROM and multi-phase outputs; 2) Advancement to sub-10fs jitter performance; 3) Development of radiation-hardened variants for aerospace; 4) Adoption of 3D packaging for reduced EMI; 5) Increased use of AI-enabled dynamic frequency scaling. The market is projected to grow at 7.2% CAGR through 2027 driven by 5G and automotive electrification.