YES Phase Locked Loops (PLL) & Frequency Synthesis Circuits 2,400+

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Part	Manufacturer	Other IC type	Temperature Grade	No. of Terminals	Package Code	Package Shape	Surface Mount	Package Body Material	Maximum Supply Current (Isup)	No. of Functions	Technology	Terminal Form	Nominal Supply Voltage (Vsup)	Power Supplies (V)	Package Style (Meter)	Package Equivalence Code	Sub-Category	Terminal Pitch	Maximum Operating Temperature	Minimum Operating Temperature	Terminal Finish	Terminal Position	JESD-30 Code	Moisture Sensitivity Level (MSL)	Maximum Supply Voltage (Vsup)	Maximum Seated Height	Width (mm)	Qualification	Minimum Supply Voltage (Vsup)	Additional Features	JESD-609 Code	Maximum Time At Peak Reflow Temperature (s)	Peak Reflow Temperature (C)	Length
74HCT9046AT	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V	WITH TWO PHASE COMPARATORS				9.9 mm
MC145170D2	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	4.5 V	3/5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	85 Cel	-40 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G16	1	5.5 V	1.75 mm	3.9 mm	Not Qualified	2.7 V		e0	30	240	9.9 mm
74HCT4046AD	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	5.5 V	1.75 mm	3.81 mm	Not Qualified	4.5 V	WITH THREE PHASE COMPARATORS	e4	30	260	9.9 mm
74HC7046ADB,118	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE, SHRINK PITCH	SOP16,.25	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V	2 mm	5.3 mm	Not Qualified	2 V		e4			6.2 mm
74HC7046APW-T	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				85 Cel	-40 Cel		DUAL	R-PDSO-G16		6 V			Not Qualified	2 V
74HC4046AT	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		6 V	1.75 mm	3.9 mm	Not Qualified	2 V					9.9 mm
74HCT7046ADB	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				85 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V			Not Qualified	4.5 V
MC145201F	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	5 V		SMALL OUTLINE	SOP20,.3		1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	2 mm	5.25 mm		4.5 V					12.675 mm
MC145225FTAR2	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	32	FQFP	SQUARE	YES	PLASTIC/EPOXY	25 mA	1	BICMOS	GULL WING			FLATPACK, FINE PITCH	TQFP32,.27SQ		.5 mm	85 Cel	-40 Cel		QUAD	S-PQFP-G32		3.6 V	1.6 mm	5 mm		1.8 V					5 mm
74HCT4046AD-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	5.5 V	1.75 mm	3.81 mm	Not Qualified	4.5 V	WITH THREE PHASE COMPARATORS	e4			9.9 mm
74HCT7046ADB-T	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				85 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V			Not Qualified	4.5 V
74HC4046AD-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	6 V	1.75 mm	3.81 mm	Not Qualified	3 V	WITH THREE PHASE COMPARATORS	e4	30	260	9.9 mm
74HCT7046APW-T	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				85 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V			Not Qualified	4.5 V
74HC7046AT-T	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		6 V	1.75 mm	3.9 mm	Not Qualified	2 V					9.9 mm
74HCT4046ATD	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V					9.9 mm
74HC7046ADB,112	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE, SHRINK PITCH	SSOP16,.3	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V	2 mm	5.3 mm	Not Qualified	2 V		e4			6.2 mm
MC145202F	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	3 V		SMALL OUTLINE	SOP20,.3		1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	2 mm	5.25 mm		2.7 V					12.675 mm
74HCT9046AT-T	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V	WITH TWO PHASE COMPARATORS				9.9 mm
MC145191DT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	5 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSOP20,.25,.26		.5 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.2 mm	4.4 mm		4.5 V					6.6 mm
74HC7046ADB-T	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V	2 mm	5.3 mm	Not Qualified	2 V		e4			6.2 mm
74HC4046APW	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSSOP16,.25	PLL or Frequency Synthesis Circuits	.65 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	6 V	1.1 mm	4.4 mm	Not Qualified	2 V		e4	30	260	5 mm
74HC7046AD,118	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V			Not Qualified	3 V	WITH TWO PHASE COMPARATORS	e4
74HCT4046AT	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V					9.9 mm
74HCT7046AD,112	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	5.5 V			Not Qualified	4.5 V	WITH TWO PHASE COMPARATORS	e4
74HC4046ADB	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE, SHRINK PITCH	SSOP16,.3	PLL or Frequency Synthesis Circuits	.65 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	6 V	2 mm	5.3 mm	Not Qualified	2 V		e4	30	260	6.2 mm
74HCT9046ADB-T	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V			Not Qualified	4.5 V
MC145220DT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	3.5 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSOP20,.25,.26		.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.05 mm	4.4 mm		2.7 V					6.6 mm
74HCT7046ATD	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V					9.9 mm
MC145191F	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	5 V		SMALL OUTLINE	SOP20,.3		1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	2 mm	5.25 mm		4.5 V					12.675 mm
74HC7046APW	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				85 Cel	-40 Cel		DUAL	R-PDSO-G16		6 V			Not Qualified	2 V
74HCT4046APW	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH			.65 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.2 mm	4.4 mm	Not Qualified	4.5 V					5 mm
74HCT4046APW-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH			.65 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.2 mm	4.4 mm	Not Qualified	4.5 V					5 mm
74HC4046ADB-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE, SHRINK PITCH			.65 mm	125 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V	2 mm	5.3 mm	Not Qualified	2 V		e4			6.2 mm
MC145170DT2	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	4.5 V	3/5	SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSSOP16,.25	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G16	3	5.5 V	1.2 mm	4.4 mm	Not Qualified	2.7 V		e0	30	240	5 mm
MC145151DW2	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	28	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			SMALL OUTLINE			1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G28		9 V	2.65 mm	7.5 mm		3 V			40	260	17.925 mm
74HC4046ATD	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		6 V	1.75 mm	3.9 mm	Not Qualified	2 V					9.9 mm
74HC7046AD	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	6 V			Not Qualified	3 V	WITH TWO PHASE COMPARATORS	e4	30	260
MC145202DT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	3 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSOP20,.25,.26		.5 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.2 mm	4.4 mm		2.7 V					6.6 mm
HEF4046BT-T	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G16		15 V	1.75 mm	3.9 mm	Not Qualified	3 V	WITH TWO PHASE COMPARATORS				9.9 mm
74HCT4046ATD-T	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V					9.9 mm
74HC7046AD-T	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				125 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V			Not Qualified	3 V	WITH TWO PHASE COMPARATORS	e4
MC145181FTAR2	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	32	LFQFP	SQUARE	YES	PLASTIC/EPOXY	25 mA	1	BICMOS	GULL WING	2.5 V		FLATPACK, LOW PROFILE, FINE PITCH	QFP32,.28SQ,20		.5 mm	85 Cel	-40 Cel		QUAD	S-PQFP-G32		3.6 V	1.6 mm	5 mm		1.8 V					5 mm
74HCT7046APW	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE				85 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V			Not Qualified	4.5 V
74HC7046ADB	NXP Semiconductors	PHASE LOCKED LOOP	INDUSTRIAL	16	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE, SHRINK PITCH	SSOP16,.3	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	6 V	2 mm	5.3 mm	Not Qualified	2 V		e4	30	260	6.2 mm
74HCT4046AD,112	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	5.5 V	1.75 mm	3.81 mm	Not Qualified	4.5 V	WITH THREE PHASE COMPARATORS	e4	30	260	9.9 mm
74HCT7046AT-T	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V		SMALL OUTLINE			1.27 mm	125 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V					9.9 mm
MC145201DT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	30 mA	1		GULL WING	5 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSOP20,.25,.26		.5 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.2 mm	4.4 mm		4.5 V					6.6 mm
74HC7046AD,112	NXP Semiconductors	PHASE LOCKED LOOP	AUTOMOTIVE	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING	5 V	2/6	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-40 Cel	Nickel/Palladium/Gold (Ni/Pd/Au)	DUAL	R-PDSO-G16	1	6 V			Not Qualified	3 V	WITH TWO PHASE COMPARATORS	e4	30	260

Phase Locked Loops (PLL) & Frequency Synthesis Circuits

Phase Locked Loops (PLL) and Frequency Synthesis Circuits are electronic circuits used to generate and control stable and precise frequencies for use in various applications, such as communication systems, signal processing, and instrumentation.

A PLL is a feedback system that compares the phase of an input signal to the phase of a reference signal and adjusts the output frequency to match the reference frequency. The basic components of a PLL include a phase detector, a low-pass filter, a voltage-controlled oscillator (VCO), and a frequency divider. The phase detector compares the phase of the input and reference signals and generates an error signal that is filtered and used to adjust the frequency of the VCO. The output of the VCO is divided by a frequency divider to generate the output frequency. PLLs are commonly used for frequency synthesis, clock recovery, and phase modulation/demodulation.

Frequency synthesis circuits are electronic circuits used to generate precise and stable frequencies by combining multiple signals with different frequencies. These circuits use various techniques, such as direct digital synthesis (DDS), fractional-N synthesis, and frequency mixing to generate frequencies. DDS is a technique that uses a digital signal generator to generate a waveform with a specific frequency, phase, and amplitude. Fractional-N synthesis is a technique that uses a PLL to generate a frequency that is a fraction of the reference frequency. Frequency mixing is a technique that combines two signals with different frequencies to generate a signal with a frequency equal to the difference between the two frequencies.

PLLs and frequency synthesis circuits are critical components in many electronic systems that require precise and stable frequencies. These circuits are used in communication systems, signal processing, instrumentation, and other applications where accurate frequency generation and control is required.