COMMERCIAL 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	Maximum Negative Supply Voltage (Vsup)	Nominal Negative Supply Voltage (Vsup)	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	Minimum Negative Supply Voltage (Vsup)	JESD-609 Code	Maximum Time At Peak Reflow Temperature (s)	Peak Reflow Temperature (C)	Length
AD9901KP	Analog Devices	PHASE DETECTOR	COMMERCIAL	20	QCCJ	SQUARE	YES	PLASTIC/EPOXY		1		J BEND			5 V	5/-5.2	CHIP CARRIER	LDCC20,.4SQ	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	0 Cel	TIN LEAD	QUAD	S-PQCC-J20	1	5.25 V	4.57 mm	8.9662 mm	Not Qualified	4.75 V	ALSO OPERATES AT -5.2 V SUPPLY		e0		225	8.9662 mm
AD9901KP-REEL	Analog Devices	PHASE DETECTOR	COMMERCIAL	20	QCCJ	SQUARE	YES	PLASTIC/EPOXY		1	BIPOLAR	J BEND			5 V	5/-5.2	CHIP CARRIER	LDCC20,.4SQ	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	0 Cel	TIN LEAD	QUAD	S-PQCC-J20	1	5.25 V	4.57 mm	8.9662 mm	Not Qualified	4.75 V	ALSO OPERATES AT -5.2 V SUPPLY		e0		225	8.9662 mm
AD9901KQ	Analog Devices	PHASE DETECTOR	COMMERCIAL	14	DIP	RECTANGULAR	NO	CERAMIC, METAL-SEALED COFIRED		1		THROUGH-HOLE			5 V	5/-5.2	IN-LINE	DIP14,.3	PLL or Frequency Synthesis Circuits	2.54 mm	70 Cel	0 Cel	TIN LEAD	DUAL	R-GDIP-T14		5.25 V	5.08 mm	7.62 mm	Not Qualified	4.75 V	ALSO OPERATES AT -5.2 V SUPPLY		e0			19.43 mm
AD9901KPZ-REEL	Analog Devices	PHASE DETECTOR	COMMERCIAL	20	QCCJ	SQUARE	YES	PLASTIC/EPOXY		1	BIPOLAR	J BEND			5 V	5/-5.2	CHIP CARRIER	LDCC20,.4SQ	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	0 Cel	MATTE TIN	QUAD	S-PQCC-J20	1	5.25 V	4.57 mm	8.9662 mm	Not Qualified	4.75 V	ALSO OPERATES AT -5.2 V SUPPLY		e3		260	8.9662 mm
LTC6905CS5#TRM	Analog Devices	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	5	VSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			3 V		SMALL OUTLINE, VERY THIN PROFILE, SHRINK PITCH			.95 mm	70 Cel	0 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G5	1	5.5 V	1 mm	1.625 mm	Not Qualified	2.7 V			e0			2.9 mm
AD802-155KR	Analog Devices	PHASE LOCKED LOOP	COMMERCIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	-5.5 V	-5.2 V	5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN LEAD	DUAL	R-PDSO-G20			2.64 mm	7.5 mm	Not Qualified		ALSO OPERATES ON -5.2 VOLT SUPPLY	-4.5 V	e0			12.8 mm
LTC6905CS5#TRPBF	Analog Devices	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	5	VSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			3 V		SMALL OUTLINE, VERY THIN PROFILE, SHRINK PITCH			.95 mm	70 Cel	0 Cel	MATTE TIN	DUAL	R-PDSO-G5	1	5.5 V	1 mm	1.625 mm	Not Qualified	2.7 V			e3	30	260	2.9 mm
LTC6905CS5#TR	Analog Devices	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	5	VSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			3 V		SMALL OUTLINE, VERY THIN PROFILE, SHRINK PITCH			.95 mm	70 Cel	0 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G5	1	5.5 V	1 mm	1.625 mm	Not Qualified	2.7 V			e0			2.9 mm
LTC6905CS5	Analog Devices	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	5	VSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			3 V		SMALL OUTLINE, VERY THIN PROFILE, SHRINK PITCH			.95 mm	70 Cel	0 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G5	1	5.5 V	1 mm	1.625 mm	Not Qualified	2.7 V			e0			2.9 mm
AD802-155KR-REEL	Analog Devices	PHASE LOCKED LOOP	COMMERCIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	-5.5 V	-5.2 V	5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN LEAD	DUAL	R-PDSO-G20			2.64 mm	7.5 mm	Not Qualified		ALSO OPERATES ON -5.2 VOLT SUPPLY	-4.5 V	e0			12.8 mm
11274-001-XTD	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN LEAD	DUAL	R-PDSO-G16		5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V			e0	30	240	9.89 mm
11274-502-XTP	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	MATTE TIN/NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V			e3/e4	40	260	9.89 mm
FS6131-01G-XTP	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN	DUAL	R-PDSO-G16	2	5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V			e3		260	9.89 mm
LC72137M	Onsemi		COMMERCIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	6 mA		CMOS	GULL WING				3/3.3	SMALL OUTLINE, SHRINK PITCH	SOP24,.3,40	PLL or Frequency Synthesis Circuits	1 mm	70 Cel	-20 Cel		DUAL	R-PDSO-G24					Not Qualified
LC72137	Onsemi		COMMERCIAL	22	SDIP	RECTANGULAR	NO	PLASTIC/EPOXY	6 mA		CMOS	THROUGH-HOLE				3/3.3	IN-LINE, SHRINK PITCH	SDIP22,.3	PLL or Frequency Synthesis Circuits	1.78 mm	70 Cel	-20 Cel		DUAL	R-PDIP-T22					Not Qualified
11274-502-XTD	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	MATTE TIN/NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V			e3/e4	40	260	9.89 mm
FS6131-01G	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	MATTE TIN/NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V			e3/e4	40	260	9.89 mm
FS6131-01	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN LEAD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V			e0	30	240	9.89 mm
FS6131-01G-XTD	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN	DUAL	R-PDSO-G16	2	5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V			e3		260	9.89 mm
11274-001-XTP	Onsemi	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	TIN LEAD	DUAL	R-PDSO-G16		5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V			e0	30	240	9.98 mm
NE565D-T	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	14	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			6 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G14		12 V	1.75 mm	3.9 mm	Not Qualified	6 V	ALSO REQUIRES -6V TO -12V SUPPLY		e4			8.65 mm
UMA1016XT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	10.8 mA	1	BIPOLAR	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V						9.9 mm
NE565F	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	14	DIP	RECTANGULAR	NO	CERAMIC, GLASS-SEALED		1	BIPOLAR	THROUGH-HOLE			6 V		IN-LINE			2.54 mm	70 Cel	0 Cel		DUAL	R-GDIP-T14		12 V	5.08 mm	7.62 mm	Not Qualified	6 V	ALSO REQUIRES -6V TO -12V SUPPLY					19.535 mm
NE567F	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	14	DIP	RECTANGULAR	NO	CERAMIC, GLASS-SEALED		1	BIPOLAR	THROUGH-HOLE			5 V		IN-LINE			2.54 mm	70 Cel	0 Cel		DUAL	R-GDIP-T14		9 V	5.08 mm	7.62 mm	Not Qualified	4.75 V						19.535 mm
NE568D-T	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G20		5.25 V	2.65 mm	7.5 mm	Not Qualified	4.75 V						12.8 mm
UMA1015M	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	12.5 mA	1	BICMOS	GULL WING			5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	70 Cel	-20 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.6 V						6.575 mm
NE567D-T	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G8		9 V	1.75 mm	3.9 mm	Not Qualified	4.75 V						4.9 mm
NE564N	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	16	DIP	RECTANGULAR	NO	PLASTIC/EPOXY	60 mA	1	BIPOLAR	THROUGH-HOLE			5 V	5	IN-LINE	DIP16,.3	PLL or Frequency Synthesis Circuits	2.54 mm	70 Cel	0 Cel		DUAL	R-PDIP-T16	1		4.2 mm	7.62 mm	Not Qualified							19.025 mm
UMA1018MDK	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	.025 mA	1	BICMOS	GULL WING			5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	70 Cel	-20 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V						6.575 mm
UMA1016BT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			5 V	5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V						9.9 mm
NE568AD-T	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G20		5.5 V	2.65 mm	7.5 mm	Not Qualified	4.5 V						12.8 mm
NE568AN	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	20	DIP	RECTANGULAR	NO	PLASTIC/EPOXY		1		THROUGH-HOLE			5 V	5	IN-LINE	DIP20,.3	PLL or Frequency Synthesis Circuits	2.54 mm	70 Cel	0 Cel		DUAL	R-PDIP-T20		5.5 V	4.2 mm	7.62 mm	Not Qualified	4.5 V						26.73 mm
NE565D	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	14	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			6 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G14		12 V	1.75 mm	3.9 mm	Not Qualified	6 V	ALSO REQUIRES -6V TO -12V SUPPLY					8.65 mm
NE564D-T	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	60 mA	1	BIPOLAR	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G16			1.93 mm	3.9 mm	Not Qualified							9.9 mm
NE565N	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	14	DIP	RECTANGULAR	NO	PLASTIC/EPOXY		1	BIPOLAR	THROUGH-HOLE			6 V		IN-LINE			2.54 mm	70 Cel	0 Cel		DUAL	R-PDIP-T14		12 V	4.2 mm	7.62 mm	Not Qualified	6 V	ALSO REQUIRES -6V TO -12V SUPPLY					19.025 mm
UMA1016AT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			5 V	5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V						9.9 mm
UMA1016AT-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V						9.9 mm
NE564D	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	60 mA	1	BIPOLAR	GULL WING			5 V	5	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G16	1		1.93 mm	3.9 mm	Not Qualified							9.9 mm
933350660602	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	16	DIP	RECTANGULAR	NO	PLASTIC/EPOXY		1	BIPOLAR	THROUGH-HOLE			5 V		IN-LINE			2.54 mm	70 Cel	0 Cel		DUAL	R-PDIP-T16			4.2 mm	7.62 mm	Not Qualified					40	245	19.025 mm
UMA1015MDK	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING			3 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	70 Cel	-20 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V						6.575 mm
UMA1018MDK-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	.025 mA	1	BICMOS	GULL WING			5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	70 Cel	-20 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V						6.575 mm
NE568D	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G20		5.25 V	2.65 mm	7.5 mm	Not Qualified	4.75 V						12.8 mm
TSA5055TD-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.75 V						9.9 mm
NE568N	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	20	DIP	RECTANGULAR	NO	PLASTIC/EPOXY		1		THROUGH-HOLE			5 V		IN-LINE			2.54 mm	70 Cel	0 Cel		DUAL	R-PDIP-T20		5.25 V	4.2 mm	7.62 mm	Not Qualified	4.75 V						26.73 mm
NE567FE	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	8	DIP	RECTANGULAR	NO	CERAMIC, GLASS-SEALED		1	BIPOLAR	THROUGH-HOLE			5 V		IN-LINE			2.54 mm	70 Cel	0 Cel		DUAL	R-GDIP-T8		9 V	5.08 mm	7.62 mm	Not Qualified	4.75 V						9.955 mm
933656140602	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16			1.93 mm	3.9 mm	Not Qualified				e4			9.9 mm
933656140623	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING			5 V		SMALL OUTLINE			1.27 mm	70 Cel	0 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16			1.93 mm	3.9 mm	Not Qualified				e4			9.9 mm
NE568AD	NXP Semiconductors	PHASE LOCKED LOOP	COMMERCIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			5 V	5	SMALL OUTLINE	SOP20,.4	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	0 Cel		DUAL	R-PDSO-G20		5.5 V	2.65 mm	7.5 mm	Not Qualified	4.5 V						12.8 mm

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.