Onsemi Phase Locked Loops (PLL) & Frequency Synthesis Circuits 107

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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	Screening Level	Terminal Form	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	JESD-609 Code	Maximum Time At Peak Reflow Temperature (s)	Peak Reflow Temperature (C)	Length
MC14046BDWG	Onsemi	PHASE LOCKED LOOP	MILITARY	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS		GULL WING		5 V	5/15	SMALL OUTLINE	SOP16,.4	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel	MATTE TIN	DUAL	R-PDSO-G16	3	18 V	2.65 mm	7.5 mm	Not Qualified	3 V	IT CAN ALSO OPERATE AT 10V OR 15V NOMINAL	e3	30	260	10.3 mm
MC74HC4046ADG	Onsemi	PHASE LOCKED LOOP	MILITARY	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS		GULL WING		4.5 V	2/6	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel	TIN	DUAL	R-PDSO-G16	1	6 V	1.75 mm	3.9 mm	Not Qualified	2 V	CONTAINS THREE PHASE COMPARATORS	e3	30	260	9.9 mm
MC14046BCPG	Onsemi	PHASE LOCKED LOOP	MILITARY	16	DIP	RECTANGULAR	NO	PLASTIC/EPOXY		1	CMOS		THROUGH-HOLE		5 V	5/15	IN-LINE	DIP16,.3	PLL or Frequency Synthesis Circuits	2.54 mm	125 Cel	-55 Cel	Tin (Sn)	DUAL	R-PDIP-T16	1	18 V	4.44 mm	7.62 mm	Not Qualified	3 V	IT CAN ALSO OPERATE AT 10V OR 15V NOMINAL	e3	40	260	19.175 mm
MCH12140DG	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL10K		GULL WING	-5.2 V		-5.2	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	MATTE TIN	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e3	30	260	4.9 mm
MCK12140DG	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL100K		GULL WING	-4.5 V		-4.5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	MATTE TIN	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e3	30	260	4.9 mm
MC14046BDWR2G	Onsemi	PHASE LOCKED LOOP	MILITARY	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS		GULL WING		5 V	5/15	SMALL OUTLINE	SOP16,.4	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel	MATTE TIN	DUAL	R-PDSO-G16	3	18 V	2.65 mm	7.5 mm	Not Qualified	3 V	IT CAN ALSO OPERATE AT 10V OR 15V NOMINAL	e3	30	260	10.3 mm
MC100EP140DG	Onsemi	PHASE DETECTOR	INDUSTRIAL	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL100K		GULL WING	-4.5 V	3.3 V	-4.5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	85 Cel	-40 Cel	MATTE TIN	DUAL	R-PDSO-G8	1	3.6 V	1.75 mm	3.9 mm	Not Qualified	3 V	NECL MODE : VCC = 0V WITH VEE = -3V TO -3.6V	e3	30	260	4.9 mm
MC100EP40DTG	Onsemi	PHASE DETECTOR	INDUSTRIAL	20	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL100K		GULL WING		3.3 V	-3/-5.5/3.3/5	SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSSOP20,.25	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G20	1	5.5 V	1.2 mm	4.4 mm	Not Qualified	3 V	NECL MODE : VCC = 0V WITH VEE = -3V TO -5.5V	e4	30	260	6.5 mm
MC74HC4046ADTG	Onsemi	PHASE LOCKED LOOP	MILITARY	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS		GULL WING		4.5 V	2/6	SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSSOP16,.25	PLL or Frequency Synthesis Circuits	.65 mm	125 Cel	-55 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	6 V	1.2 mm	4.4 mm	Not Qualified	2 V		e4	30	260	5 mm
MC74HC4046AD	Onsemi	PHASE LOCKED LOOP	MILITARY	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	CMOS		GULL WING		4.5 V	2/6	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel	TIN LEAD	DUAL	R-PDSO-G16	1	6 V	1.75 mm	3.9 mm	Not Qualified	2 V	CONTAINS THREE PHASE COMPARATORS	e0		235	9.9 mm
MCK12140DR2	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL100K		GULL WING	-4.5 V		-4.5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e0	30	235	4.9 mm
LC72121V-D-TLM-E	Onsemi		INDUSTRIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	6 mA		CMOS		GULL WING			3/3.3	SMALL OUTLINE, SHRINK PITCH	SSOP24,.3	PLL or Frequency Synthesis Circuits	.635 mm	85 Cel	-40 Cel	TIN BISMUTH	DUAL	R-PDSO-G24	4				Not Qualified			e6	30	260
LC72121V-D-TML-E	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	24	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1			GULL WING				SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24		3.6 V	1.5 mm	5.6 mm		2.7 V					7.8 mm
LC72130	Onsemi		INDUSTRIAL	24	SDIP	RECTANGULAR	NO	PLASTIC/EPOXY	10 mA		CMOS		THROUGH-HOLE		5 V	5	IN-LINE, SHRINK PITCH	SDIP24,.3	PLL or Frequency Synthesis Circuits	1.78 mm	85 Cel	-40 Cel		DUAL	R-PDIP-T24					Not Qualified
LC72121V	Onsemi		INDUSTRIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	6 mA		CMOS		GULL WING			3/3.3	SMALL OUTLINE, SHRINK PITCH	SSOP24,.3	PLL or Frequency Synthesis Circuits	.635 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
LC72121V-D-MPB-E	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	24	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	6 mA	1	CMOS		GULL WING			3/3.3	SMALL OUTLINE, LOW PROFILE, SHRINK PITCH	SSOP24,.3	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	TIN BISMUTH	DUAL	R-PDSO-G24	4	3.6 V	1.5 mm	5.6 mm	Not Qualified	2.7 V		e6	30	260	7.8 mm
LC72121V-TLM-E	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	24	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	6 mA	1	CMOS		GULL WING			3/3.3	SMALL OUTLINE, LOW PROFILE, SHRINK PITCH	SSOP24,.3	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel	TIN BISMUTH	DUAL	R-PDSO-G24	4	3.6 V	1.5 mm	5.6 mm	Not Qualified	2.7 V		e6	30	260	7.8 mm
LC72121-D-E	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	22	DIP	RECTANGULAR	NO	PLASTIC/EPOXY	6 mA	1	CMOS		THROUGH-HOLE			3/3.3	IN-LINE	SDIP22,.3	PLL or Frequency Synthesis Circuits	1.78 mm	85 Cel	-40 Cel	Tin/Bismuth (Sn/Bi)	DUAL	R-PDIP-T22		3.6 V	3.9 mm	7.62 mm	Not Qualified	2.7 V		e6			21 mm
MCH12140DR2G	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL10K		GULL WING	-5.2 V		-5.2	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	TIN	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e3	30	260	4.9 mm
MCK12140D	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL100K		GULL WING	-4.5 V		-4.5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e0	30	235	4.9 mm
FS6131-01I-XTP	Onsemi	PLL FREQUENCY SYNTHESIZER	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	1	5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V					9.89 mm
NLV74HC4046ADR2G	Onsemi	PHASE LOCKED LOOP	MILITARY	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	.16 mA	1	CMOS	AEC-Q100	GULL WING		5 V	2/6	SMALL OUTLINE	SOP16,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel	TIN	DUAL	R-PDSO-G16	1	6 V	1.75 mm	3.9 mm	Not Qualified	2 V		e3	30	260	9.9 mm
MM74HC4046SJX	Onsemi	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	MATTE TIN	DUAL	R-PDSO-G16	1	6 V	2.1 mm	5.3 mm	Not Qualified	2 V		e3			10.1 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
LC72146V	Onsemi		INDUSTRIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	15 mA		CMOS		GULL WING		5 V	5	SMALL OUTLINE, SHRINK PITCH	SSOP24,.3	PLL or Frequency Synthesis Circuits	.635 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
LC72131KMA	Onsemi	PLL FREQUENCY SYNTHESIZER
LC7185-8750	Onsemi		INDUSTRIAL	30	SDIP	RECTANGULAR	NO	PLASTIC/EPOXY	10 mA		CMOS		THROUGH-HOLE			5/8	IN-LINE, SHRINK PITCH	SDIP30,.4	PLL or Frequency Synthesis Circuits	1.78 mm	85 Cel	-40 Cel		DUAL	R-PDIP-T30					Not Qualified
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
MCH12140DR2	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL10K		GULL WING	-5.2 V		-5.2	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e0	30	235	4.9 mm
LV2134V	Onsemi		OTHER	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	22 mA		BICMOS		GULL WING		2.2 V	2.2	SMALL OUTLINE, SHRINK PITCH	SSOP24,.3	PLL or Frequency Synthesis Circuits	.635 mm	70 Cel	-25 Cel		DUAL	R-PDSO-G24					Not Qualified
LC72146M	Onsemi		INDUSTRIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	15 mA		CMOS		GULL WING		5 V	5	SMALL OUTLINE, SHRINK PITCH	SOP24,.3,40	PLL or Frequency Synthesis Circuits	1 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
LC72131K-E	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	22	DIP	RECTANGULAR	NO	PLASTIC/EPOXY		1			THROUGH-HOLE		5 V		IN-LINE			1.78 mm	85 Cel	-40 Cel		DUAL	R-PDIP-T22		5.5 V	3.9 mm	7.62 mm		4.5 V					21 mm
LC72121MA	Onsemi	PLL FREQUENCY SYNTHESIZER
LC72144M	Onsemi		INDUSTRIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	15 mA		CMOS		GULL WING		5 V	5	SMALL OUTLINE, SHRINK PITCH	SOP24,.3,40	PLL or Frequency Synthesis Circuits	1 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
LC7152NM	Onsemi		INDUSTRIAL	24	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	14 mA		CMOS		GULL WING			2/3.3	SMALL OUTLINE	SOP24,.3	PLL or Frequency Synthesis Circuits	1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
LC72131KMA-AE	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	10 mA	1	CMOS		GULL WING		5 V	5	SMALL OUTLINE	SOP20,.3	PLL or Frequency Synthesis Circuits	1.27 mm	85 Cel	-40 Cel	TIN SILVER	DUAL	R-PDSO-G20	3	5.5 V	2 mm	5.4 mm	Not Qualified	4.5 V		e2	30	260	12.7 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
MCK12140DR2G	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL100K		GULL WING	-4.5 V		-4.5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	MATTE TIN	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e3	30	260	4.9 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
LC72130M	Onsemi		INDUSTRIAL	24	SSOP	RECTANGULAR	YES	PLASTIC/EPOXY	10 mA		CMOS		GULL WING		5 V	5	SMALL OUTLINE, SHRINK PITCH	SOP24,.3,40	PLL or Frequency Synthesis Circuits	1 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
MCH12140D	Onsemi	PHASE DETECTOR	OTHER	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	ECL10K		GULL WING	-5.2 V		-5.2	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	70 Cel	-40 Cel	Tin/Lead (Sn/Pb)	DUAL	R-PDSO-G8	1		1.75 mm	3.9 mm	Not Qualified		IT REQUIRES A -4.75V TO -5.5V SUPPLY	e0	30	235	4.9 mm
LC72121	Onsemi		INDUSTRIAL	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	85 Cel	-40 Cel		DUAL	R-PDIP-T22					Not Qualified
LC72121M-TLM-E	Onsemi	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	24	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	6 mA	1	CMOS		GULL WING			3/3.3	SMALL OUTLINE, LOW PROFILE, SHRINK PITCH	SOP24,.3,40	PLL or Frequency Synthesis Circuits	1 mm	85 Cel	-40 Cel	TIN BISMUTH	DUAL	R-PDSO-G24	4	3.6 V	1.7 mm	5.4 mm	Not Qualified	2.7 V		e6	30	260	12.5 mm
FS6131-01I-XTD	Onsemi	PLL FREQUENCY SYNTHESIZER	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	1	5.5 V	1.73 mm	3.9 mm	Not Qualified	4.5 V					9.89 mm
LC72121M	Onsemi		INDUSTRIAL	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	85 Cel	-40 Cel		DUAL	R-PDSO-G24					Not Qualified
PCS1I2860AG-16TT	Onsemi		INDUSTRIAL	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY			CMOS		GULL WING		3.3 V	3.3	SMALL OUTLINE, THIN PROFILE, SHRINK PITCH	TSSOP16,.25	PLL or Frequency Synthesis Circuits	.635 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G16					Not Qualified

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.