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
UMA1020AM	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	11 mA	1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 mm
TDD1742T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	28	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	1.5 mA	1	CMOS	GULL WING	7.4 V		SMALL OUTLINE			1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G28		10 V	2.65 mm	7.5 mm	Not Qualified	7 V					17.9 mm
TSA5521T-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	85 Cel	-20 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY				9.9 mm
935267009118	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-20 Cel		DUAL	R-PDSO-G16		5.25 V	1.5 mm	4.4 mm	Not Qualified	4.75 V					5.2 mm
SA7025DK-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V	SELECTABLE 64/65/72 PRESCALER				6.5 mm
TSA5059TS	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-20 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.25 V	1.5 mm	4.4 mm	Not Qualified	4.75 V		e4			5.2 mm
SE567D-T	NXP Semiconductors	PHASE LOCKED LOOP	MILITARY	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING	5 V	5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel		DUAL	R-PDSO-G8		9 V	1.75 mm	3.9 mm	Not Qualified	4.75 V					4.9 mm
UMA1015AM-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		6 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 mm
UMA1021M-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	3 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 mm
935044180118	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	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V		e4			9.9 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
935260845118	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	3 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V		e4			5.2 mm
SA8026DK-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	3.75 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V		e4			6.5 mm
935184340512	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL EXTENDED	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	80 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V			NOT SPECIFIED	NOT SPECIFIED	9.9 mm
935044180112	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	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16	1	5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V		e4			9.9 mm
TSA5514AT-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL EXTENDED	20	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	80 Cel	-10 Cel		DUAL	R-PDSO-G20		5.5 V	2.65 mm	7.5 mm	Not Qualified	4.5 V					12.8 mm
OM5156M	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	3 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V		e4			6.5 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
UMA1017MDK	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	.025 mA	1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.575 mm
935044180699	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	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V		e4			9.9 mm
TSA5527T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	85 Cel	-20 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY	e4			9.9 mm
TSA5520T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	85 Cel	-20 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY				9.9 mm
SE567DSIIA	NXP Semiconductors		MILITARY	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY			BIPOLAR	GULL WING	5 V	5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel		DUAL	R-PDSO-G8					Not Qualified
SA567D-T	NXP Semiconductors	PHASE LOCKED LOOP		8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING			SMALL OUTLINE			1.27 mm				DUAL	R-PDSO-G8			1.75 mm	3.9 mm	Not Qualified						4.9 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
SA7015DK	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V	SELECTABLE 64/65/72 PRESCALER				6.5 mm
TSA5526AM-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-20 Cel		DUAL	R-PDSO-G16		5.5 V	1.5 mm	4.4 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY				5.2 mm
TSA5527AM	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-20 Cel		DUAL	R-PDSO-G16		5.5 V	1.5 mm	4.4 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY				5.2 mm
TSA5512MDK-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL EXTENDED	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	80 Cel	-10 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	4.5 V					6.5 mm
UMA1015AM	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V	3/5	SMALL OUTLINE, LOW PROFILE, SHRINK PITCH	SSOP20,.25	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		6 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 mm
SE567D	NXP Semiconductors	PHASE LOCKED LOOP	MILITARY	8	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BIPOLAR	GULL WING	5 V	5	SMALL OUTLINE	SOP8,.25	PLL or Frequency Synthesis Circuits	1.27 mm	125 Cel	-55 Cel		DUAL	R-PDSO-G8		9 V	1.75 mm	3.9 mm	Not Qualified	4.75 V					4.9 mm
TSA5512TD	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL EXTENDED	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	80 Cel	-10 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V		e4			9.9 mm
935184340518	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL EXTENDED	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	80 Cel	-10 Cel		DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V					9.9 mm
SA7025DK	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V	3/5	SMALL OUTLINE, LOW PROFILE, SHRINK PITCH	SSOP20,.25	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20	1	5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V	SELECTABLE 64/65/72 PRESCALER				6.5 mm
TSA5512TD-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	COMMERCIAL EXTENDED	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	80 Cel	-10 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V		e4			9.9 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
UMA1019AM-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	11 mA	1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 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
SA8025DK-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G20		5.5 V	1.7 mm	4.4 mm	Not Qualified	2.7 V	SELECTABLE 64/65/68/73 PRESCALER				6.575 mm
UMA1020M	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 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
SA8016-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	16	TSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1	BICMOS	GULL WING	3 V		SMALL OUTLINE, THIN PROFILE, SHRINK PITCH			.65 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G16		5.5 V	1.1 mm	4.4 mm	Not Qualified	2.7 V					5 mm
TSA5527AT	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	SOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE			1.27 mm	85 Cel	-20 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		5.5 V	1.75 mm	3.9 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY	e4			9.9 mm
TSA5520MDK-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	16	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY		1		GULL WING	5 V		SMALL OUTLINE, LOW PROFILE, SHRINK PITCH			.65 mm	85 Cel	-20 Cel		DUAL	R-PDSO-G16		5.5 V	1.5 mm	4.4 mm	Not Qualified	4.5 V	ALSO REQUIRES 4.5V TO 13.5V SUPPLY				5.2 mm
TDD1742TD-T	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	28	SOP	RECTANGULAR	YES	PLASTIC/EPOXY	1.5 mA	1	CMOS	GULL WING	7.4 V		SMALL OUTLINE			1.27 mm	85 Cel	-40 Cel		DUAL	R-PDSO-G28		10 V	2.65 mm	7.5 mm	Not Qualified	7 V					17.9 mm
SA8028W,518	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	INDUSTRIAL	24	HVBCC	SQUARE	YES	PLASTIC/EPOXY		1	BICMOS	BUTT	3 V		CHIP CARRIER, HEAT SINK/SLUG, VERY THIN PROFILE			.5 mm	85 Cel	-40 Cel		BOTTOM	S-PBCC-B24		3.6 V	.8 mm	4 mm	Not Qualified	2.7 V			NOT SPECIFIED	NOT SPECIFIED	4 mm
UMA1019AM	NXP Semiconductors	PLL FREQUENCY SYNTHESIZER	OTHER	20	LSSOP	RECTANGULAR	YES	PLASTIC/EPOXY	11 mA	1	BICMOS	GULL WING	5 V	3/5	SMALL OUTLINE, LOW PROFILE, SHRINK PITCH	SSOP20,.25	PLL or Frequency Synthesis Circuits	.65 mm	85 Cel	-30 Cel		DUAL	R-PDSO-G20		5.5 V	1.5 mm	4.4 mm	Not Qualified	2.7 V					6.5 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.