COMMERCIAL EXTENDED Telephone Line ICs 216

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Part	Manufacturer	Telecom IC Type	Temperature Grade	Terminal Form	No. of Terminals	Package Code	Package Shape	Package Body Material	Surface Mount	No. of Functions	Technology	Maximum Supply Current	Nominal Supply Voltage	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 Seated Height	Width	Qualification	Crystal Frequency (MHz)	JESD-609 Code	Maximum Time At Peak Reflow Temperature (s)	Peak Reflow Temperature (C)	Make-break Ratio	Length
BA8206F-E2	ROHM	TELEPHONE RINGER CIRCUIT	COMMERCIAL EXTENDED	GULL WING	8	LSOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR	.0017 mA	24 V	24	SMALL OUTLINE, LOW PROFILE	SOP8,.25	Telephone Circuits	1.27 mm	75 Cel	-25 Cel	TIN/TIN COPPER	DUAL	R-PDSO-G8		1.6 mm	4.4 mm	Not Qualified		e3/e2	10	260		5 mm
TEA1064BT	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	20	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR	.0016 mA	2.7 V	2.7	SMALL OUTLINE	SOP20,.4	Telephone Circuits	1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G20		2.65 mm	7.5 mm	Not Qualified						12.8 mm
PCD3312CT	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	8	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	CMOS	.0009 mA	3 V	3/5	SMALL OUTLINE	SOP8,.4	Telephone Circuits	1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G8		2.65 mm	7.5 mm	Not Qualified	3.58					7.55 mm
BA8206	ROHM	TELEPHONE RINGER CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	8	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR	.0017 mA	24 V	24	IN-LINE	DIP8,.3	Telephone Circuits	2.54 mm	75 Cel	-25 Cel	TIN/TIN COPPER	DUAL	R-PDIP-T8		3.7 mm	7.62 mm	Not Qualified		e3/e2	10	260		9.3 mm
L3916AN	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3 V	3	IN-LINE	DIP28,.6	Other Telecom ICs	2.54 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDIP-T28			15.24 mm	Not Qualified		e0			1:1.5	36.83 mm
L3934AD	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3 V	3	SMALL OUTLINE	SOP28,.4	Other Telecom ICs	1.27 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e0			1:1.5	17.9 mm
L3936AN	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3 V	3	IN-LINE	DIP28,.6	Other Telecom ICs	2.54 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDIP-T28			15.24 mm	Not Qualified		e0			1:1.5	36.83 mm
L3914AN	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3 V	3	IN-LINE	DIP28,.6	Other Telecom ICs	2.54 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDIP-T28			15.24 mm	Not Qualified		e0			1:1.5	36.83 mm
L3924AD	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3 V	3	SMALL OUTLINE	SOP28,.4	Other Telecom ICs	1.27 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e0			1:1.5	17.9 mm
L3926AD	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3 V	3	SMALL OUTLINE	SOP28,.4	Other Telecom ICs	1.27 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e0			1:1.5	17.9 mm
L3916AD	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3 V	3	SMALL OUTLINE	SOP28,.4	Other Telecom ICs	1.27 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e0			1:1.5	17.9 mm
L3926AN	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3 V	3	IN-LINE	DIP28,.6	Other Telecom ICs	2.54 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDIP-T28			15.24 mm	Not Qualified		e0			1:1.5	36.83 mm
L3914AD	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3 V	3	SMALL OUTLINE	SOP28,.4	Other Telecom ICs	1.27 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e0			1:1.5	17.9 mm
L3924AN	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3 V	3	IN-LINE	DIP28,.6	Other Telecom ICs	2.54 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDIP-T28			15.24 mm	Not Qualified		e0			1:1.5	36.83 mm
L3934AN	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3 V	3	IN-LINE	DIP28,.6	Other Telecom ICs	2.54 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDIP-T28			15.24 mm	Not Qualified		e0			1:1.5	36.83 mm
L3936AD	STMicroelectronics	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3 V	3	SMALL OUTLINE	SOP28,.4	Other Telecom ICs	1.27 mm	75 Cel	-25 Cel	TIN LEAD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e0			1:1.5	17.9 mm
PCD3311CT-T	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	16	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	CMOS		3 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G16		2.65 mm	7.5 mm	Not Qualified						10.3 mm
935083210118	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	16	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			2.7 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G16		1.75 mm	3.9 mm	Not Qualified			NOT SPECIFIED	NOT SPECIFIED		9.9 mm
933880320112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	20	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		2.8 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G20		2.65 mm	7.5 mm	Not Qualified			NOT SPECIFIED	NOT SPECIFIED		12.8 mm
935263448557	NXP Semiconductors	SPEAKER PHONE CIRCUIT	COMMERCIAL EXTENDED	GULL WING	44	QFP	SQUARE	PLASTIC/EPOXY	YES	1	BIPOLAR		3.35 V		FLATPACK			.8 mm	75 Cel	-25 Cel		QUAD	S-PQFP-G44		2.1 mm	10 mm	Not Qualified						10 mm
935151250112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	16	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1			2.7 V		IN-LINE			2.54 mm	75 Cel	-25 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDIP-T16	1	4.32 mm	7.62 mm	Not Qualified		e4				38.1 mm
935260128512	NXP Semiconductors	SPEAKER PHONE CIRCUIT	COMMERCIAL EXTENDED	GULL WING	24	SSOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		5 V		SMALL OUTLINE, SHRINK PITCH			.65 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G24		2 mm	5.3 mm	Not Qualified						8.2 mm
935260608112	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
UBA2051T/C1	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
935260607112	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
935078740112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	16	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1			2.7 V		IN-LINE			2.54 mm	75 Cel	-25 Cel	TIN	DUAL	R-PDIP-T16		4.32 mm	7.62 mm	Not Qualified		e3				38.1 mm
935260128118	NXP Semiconductors	SPEAKER PHONE CIRCUIT	COMMERCIAL EXTENDED	GULL WING	24	SSOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		5 V		SMALL OUTLINE, SHRINK PITCH			.65 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G24		2 mm	5.3 mm	Not Qualified						8.2 mm
UBA1702	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1		2 mA	3.3 V	3.3	IN-LINE	DIP28,.6	Telephone Circuits	2.54 mm	75 Cel	-25 Cel		DUAL	R-PDIP-T28		5.1 mm	15.24 mm	Not Qualified						35.5 mm
935260690112	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
935084930112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	20	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		2.8 V		IN-LINE			2.54 mm	75 Cel	-25 Cel		DUAL	R-PDIP-T20		4.2 mm	7.62 mm	Not Qualified			40	245		26.73 mm
UBA1702A	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	28	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1		2 mA	3.3 V	3.3	IN-LINE	DIP28,.6	Telephone Circuits	2.54 mm	75 Cel	-25 Cel		DUAL	R-PDIP-T28		5.1 mm	15.24 mm	Not Qualified						35.5 mm
935260687118	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
PCD3312CT-T	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	8	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	CMOS		3 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G8		2.65 mm	7.5 mm	Not Qualified						7.55 mm
935079230112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	16	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1			2.7 V		IN-LINE			2.54 mm	75 Cel	-25 Cel	TIN	DUAL	R-PDIP-T16		4.32 mm	7.62 mm	Not Qualified		e3				38.1 mm
935207850112	NXP Semiconductors	SPEAKER PHONE CIRCUIT	COMMERCIAL EXTENDED	GULL WING	24	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		5 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G24		2.65 mm	7.5 mm	Not Qualified						15.4 mm
PCD3311CP	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	14	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	CMOS	.0009 mA	3 V	3/5	IN-LINE	DIP14,.3	Telephone Circuits	2.54 mm	75 Cel	-25 Cel		DUAL	R-PDIP-T14		4.2 mm	7.62 mm	Not Qualified	3.58					19.025 mm
935263380512	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	16	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G16		1.75 mm	3.9 mm	Not Qualified						9.9 mm
935083210112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	16	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			2.7 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G16		1.75 mm	3.9 mm	Not Qualified			NOT SPECIFIED	NOT SPECIFIED		9.9 mm
935084920112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	20	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		2.8 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G20		2.65 mm	7.5 mm	Not Qualified						12.8 mm
935260608118	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
UBA1702AT-T	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1		2 mA	3.3 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified		e4				17.9 mm
935262584518	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	16	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3.3 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel	NICKEL PALLADIUM GOLD	DUAL	R-PDSO-G16		1.75 mm	3.9 mm	Not Qualified		e4				9.9 mm
UBA2051AT/C1	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
935084920118	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	GULL WING	20	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		2.8 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G20		2.65 mm	7.5 mm	Not Qualified						12.8 mm
935263449118	NXP Semiconductors	SPEAKER PHONE CIRCUIT	COMMERCIAL EXTENDED	GULL WING	40	SSOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3.35 V		SMALL OUTLINE, SHRINK PITCH			.762 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G40		2.7 mm	7.55 mm	Not Qualified			NOT SPECIFIED	NOT SPECIFIED		15.4 mm
935263379112	NXP Semiconductors	TELEPHONE SPEECH CIRCUIT	COMMERCIAL EXTENDED	THROUGH-HOLE	16	DIP	RECTANGULAR	PLASTIC/EPOXY	NO	1	BIPOLAR		3.6 V		IN-LINE			2.54 mm	75 Cel	-25 Cel		DUAL	R-PDIP-T16		4.2 mm	7.62 mm	Not Qualified						19.025 mm
935260607118	NXP Semiconductors	TELEPHONE MULTIFUNCTION CIRCUIT	COMMERCIAL EXTENDED	GULL WING	28	SOP	RECTANGULAR	PLASTIC/EPOXY	YES	1			3.6 V		SMALL OUTLINE			1.27 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G28		2.65 mm	7.5 mm	Not Qualified					2:3	17.9 mm
935263449112	NXP Semiconductors	SPEAKER PHONE CIRCUIT	COMMERCIAL EXTENDED	GULL WING	40	SSOP	RECTANGULAR	PLASTIC/EPOXY	YES	1	BIPOLAR		3.35 V		SMALL OUTLINE, SHRINK PITCH			.762 mm	75 Cel	-25 Cel		DUAL	R-PDSO-G40		2.7 mm	7.55 mm	Not Qualified						15.4 mm

Telephone Line ICs

Telephone Line ICs are electronic components used in telephone systems to interface with the telephone line and provide necessary functionality for telephone communication. These ICs are designed to provide reliable and efficient operation of the telephone line, allowing for clear and uninterrupted communication between two devices.

Telephone Line ICs use various techniques to interface with the telephone line, including pulse dialing, dual-tone multi-frequency (DTMF) signaling, and loop current sensing. Pulse dialing is used to send a series of electrical pulses over the telephone line to dial a phone number. DTMF signaling is used to send a sequence of tones to control various telephone functions, such as call forwarding and call waiting. Loop current sensing is used to detect the presence of a telephone off-hook condition, allowing the telephone system to provide appropriate signaling and call management.

Some common features of Telephone Line ICs include:

1. Telephone line interface: Telephone Line ICs provide the necessary interface with the telephone line to enable telephone communication.

2. Signal processing: Telephone Line ICs are designed to process signals quickly and efficiently, ensuring clear and uninterrupted communication.

3. Tone generation and detection: Telephone Line ICs can generate and detect various tones used for telephone communication, such as dial tones and busy signals.

4. Call management: Telephone Line ICs can provide call management functions, such as call waiting and call forwarding.

Telephone Line ICs are used in a variety of telephone systems, including traditional landline phones, cordless phones, and PBX (Private Branch Exchange) systems. They are also used in other communication systems that require telephone line interface, such as alarm systems and security systems.