SINGLE Triode For Alternating Current (TRIAC) 2,400+

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Part RoHS Manufacturer Trigger Device Type Package Style (Meter) Surface Mount Terminal Position Configuration Case Connection Maximum On-state Voltage Package Body Material Maximum DC Gate Trigger Current Non Repetitive Peak On-state Current Terminal Form Package Shape Maximum On-state Current No. of Elements Maximum Leakage Current Repetitive Peak Reverse Voltage Maximum Repetitive Peak Off-state Leakage Current No. of Terminals Sub-Category Maximum Operating Temperature Minimum Operating Temperature Terminal Finish Maximum RMS On-state Current JESD-30 Code Moisture Sensitivity Level (MSL) Maximum DC Gate Trigger Voltage Qualification Repetitive Peak Off-state Voltage Minimum Critical Rate of Rise of Commutation Voltage Minimum Critical Rate of Rise of Off-state Voltage Maximum Holding Current Additional Features JEDEC-95 Code JESD-609 Code Maximum Time At Peak Reflow Temperature (s) Peak Reflow Temperature (C) Reference Standard

T1235-600G-TR

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

GULL WING

RECTANGULAR

1

.005 mA

2

TRIACs

125 Cel

-40 Cel

MATTE TIN

12 A

R-PSSO-G2

1.3 V

Not Qualified

600 V

500 V/us

35 mA

e3

T2035H-6G-TR

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

GULL WING

RECTANGULAR

1

2

TRIACs

125 Cel

-40 Cel

MATTE TIN

20 A

R-PSSO-G2

1

1 V

Not Qualified

600 V

1000 V/us

35 mA

e3

Z0405MF1AA2

STMicroelectronics

4 QUADRANT LOGIC LEVEL TRIAC

IN-LINE

NO

SINGLE

SINGLE

PLASTIC/EPOXY

5 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

3

TRIACs

125 Cel

-40 Cel

TIN

4 A

R-PSIP-T3

1.3 V

Not Qualified

600 V

1 V/us

20 V/us

5 mA

SENSITIVE GATE

e3

BTA208S-800B,118

NXP Semiconductors

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

GULL WING

RECTANGULAR

1

.5 mA

500 uA

2

TRIACs

125 Cel

TIN

8 A

R-PSSO-G2

1

1.5 V

Not Qualified

800 V

1000 V/us

60 mA

TO-252

e3

BTB08-600CWRG

STMicroelectronics

SNUBBERLESS TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

1 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

8 A

R-PSFM-T3

1.3 V

Not Qualified

600 V

400 V/us

35 mA

TO-220AB

e3

Q4015LT58

Littelfuse

TRIAC WITH INT TRIGGER

FLANGE MOUNT

NO

SINGLE

SINGLE WITH BUILT-IN TRIGGER ELEMENT IN SERIES WITH GATE

ISOLATED

PLASTIC/EPOXY

THROUGH-HOLE

RECTANGULAR

1

3

Matte Tin (Sn)

15 A

R-PSFM-T3

2

Not Qualified

400 V

TO-220AB

e3

10

260

UL RECOGNIZED

2N6348AG

Onsemi

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

125 mA

THROUGH-HOLE

RECTANGULAR

1

2 mA

3

TRIACs

125 Cel

-40 Cel

TIN

12 A

R-PSFM-T3

3 V

Not Qualified

600 V

75 mA

TO-220AB

e3

260

ACST830-8GTR

STMicroelectronics

TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

PLASTIC/EPOXY

30 mA

GULL WING

RECTANGULAR

1

1 mA

2

TRIACs

125 Cel

-40 Cel

Matte Tin (Sn) - annealed

8 A

R-PSSO-G2

1

1 V

Not Qualified

800 V

2000 V/us

30 mA

e3

30

245

BT136-600D,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

5 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

4 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

10 mA

SENSITIVE GATE

TO-220AB

e3

BTA16-800SW3G

Onsemi

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

10 mA

THROUGH-HOLE

RECTANGULAR

1

2 mA

3

TRIACs

110 Cel

-40 Cel

TIN

16 A

R-PSFM-T3

1.3 V

Not Qualified

800 V

250 V/us

20 mA

TO-220AB

e3

260

BTA208S-800E,118

NXP Semiconductors

TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

10 mA

GULL WING

RECTANGULAR

1

.5 mA

2

TRIACs

125 Cel

TIN

8 A

R-PSSO-G2

1

1.5 V

Not Qualified

800 V

20 V/us

12 mA

SENSITIVE GATE

TO-252AA

e3

BTA225-600BT

NXP Semiconductors

SNUBBERLESS TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

THROUGH-HOLE

RECTANGULAR

1

5 mA

3

TRIACs

150 Cel

-40 Cel

TIN

25 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

1000 V/us

60 mA

TO-220AB

e3

L4004D5RP

Littelfuse

4 QUADRANT LOGIC LEVEL TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

1.6 V

PLASTIC/EPOXY

5 mA

GULL WING

RECTANGULAR

1

.2 mA

400 V

200 uA

2

110 Cel

-40 Cel

MATTE TIN

4 A

R-PSSO-G2

1.3 V

Not Qualified

400 V

10 mA

TO-252AA

e3

40

260

UL RECOGNIZED

BT139-600,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

16 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

100 V/us

30 mA

TO-220AB

e3

BTB08-600BRG

STMicroelectronics

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

THROUGH-HOLE

RECTANGULAR

1

1 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

8 A

R-PSFM-T3

1.3 V

Not Qualified

600 V

10 V/us

400 V/us

50 mA

TO-220AB

e3

T1235H-6G

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

GULL WING

RECTANGULAR

1

2

TRIACs

150 Cel

-40 Cel

MATTE TIN

12 A

R-PSSO-G2

1 V

Not Qualified

600 V

1000 V/us

35 mA

e3

T835H-6T

STMicroelectronics

TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

3

TRIACs

150 Cel

-40 Cel

MATTE TIN

8 A

R-PSFM-T3

1 V

Not Qualified

600 V

14 V/us

1500 V/us

35 mA

TO-220AB

e3

BCR16PM-12LB

Renesas Electronics

TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

30 mA

THROUGH-HOLE

RECTANGULAR

1

2 mA

3

TRIACs

150 Cel

-40 Cel

16 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

1 V/us

TO-220AB

BT136-800E

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

10 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

4 A

R-PSFM-T3

1.5 V

Not Qualified

800 V

50 V/us

15 mA

SENSITIVE GATE

TO-220AB

e3

L4004V3TP

Littelfuse

4 QUADRANT LOGIC LEVEL TRIAC

IN-LINE

NO

SINGLE

SINGLE

MAIN TERMINAL 2

1.6 V

PLASTIC/EPOXY

3 mA

THROUGH-HOLE

RECTANGULAR

1

.2 mA

400 V

200 uA

3

110 Cel

-40 Cel

MATTE TIN

4 A

R-PSIP-T3

2

1.3 V

Not Qualified

400 V

5 mA

TO-251AA

e3

40

260

UL RECOGNIZED

Z0409MF0AA2

STMicroelectronics

4 QUADRANT LOGIC LEVEL TRIAC

IN-LINE

NO

SINGLE

SINGLE

PLASTIC/EPOXY

10 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

4 A

R-PSIP-T3

1.3 V

Not Qualified

600 V

2 V/us

100 V/us

10 mA

e3

T1650H-6G

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

GULL WING

RECTANGULAR

1

2

TRIACs

150 Cel

-40 Cel

MATTE TIN

16 A

R-PSSO-G2

1 V

Not Qualified

600 V

21 V/us

1000 V/us

75 mA

e3

ACST1210-7GTR

STMicroelectronics

TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

PLASTIC/EPOXY

10 mA

GULL WING

RECTANGULAR

1

1.5 mA

2

TRIACs

125 Cel

-40 Cel

Matte Tin (Sn) - annealed

12 A

R-PSSO-G2

1

1 V

Not Qualified

700 V

200 V/us

30 mA

HIGH RELIABILITY

e3

30

245

ACST410-8B

STMicroelectronics

TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

PLASTIC/EPOXY

10 mA

GULL WING

RECTANGULAR

1

.5 mA

2

TRIACs

125 Cel

-40 Cel

MATTE TIN

4 A

R-PSSO-G2

1

1 V

Not Qualified

800 V

500 V/us

20 mA

e3

30

260

ACST410-8FP

STMicroelectronics

TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

10 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

4 A

R-PSFM-T3

1 V

Not Qualified

800 V

500 V/us

20 mA

TO-220AB

e3

BT137S-600E/T3

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

10 mA

GULL WING

RECTANGULAR

1

500 uA

2

125 Cel

TIN

8 A

R-PSSO-G2

1

1.5 V

Not Qualified

600 V

20 mA

SENSITIVE GATE

TO-252

e3

T1235T-6I

STMicroelectronics

SNUBBERLESS TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

1 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

12 A

R-PSFM-T3

1.3 V

Not Qualified

600 V

1000 V/us

30 mA

TO-220AB

e3

T2535-600G-TR

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

GULL WING

RECTANGULAR

1

3 mA

2

TRIACs

125 Cel

-40 Cel

Matte Tin (Sn) - annealed

25 A

R-PSSO-G2

1

1.3 V

Not Qualified

600 V

500 V/us

50 mA

e3

30

245

UL RECOGNIZED

2N6075BG

Onsemi

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

15 mA

THROUGH-HOLE

RECTANGULAR

1

2 mA

3

TRIACs

110 Cel

-40 Cel

TIN

4 A

R-PSFM-T3

2.5 V

Not Qualified

600 V

30 mA

CMOS COMPATIBLE

TO-225

e3

260

BTA10-600GPRG

STMicroelectronics

TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

PLASTIC/EPOXY

50 mA

THROUGH-HOLE

RECTANGULAR

1

3

TRIACs

125 Cel

-40 Cel

10 A

R-PSFM-T3

1.5 V

600 V

1 V/us

100 V/us

13 mA

TO-220AB

NOT SPECIFIED

NOT SPECIFIED

UL RECOGNIZED

T2550-12T

STMicroelectronics

SNUBBERLESS TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

THROUGH-HOLE

RECTANGULAR

1

1200 V

10 uA

3

125 Cel

-40 Cel

25 A

R-PSFM-T3

1.3 V

1200 V

20 V/us

2500 V/us

60 mA

NOT SPECIFIED

NOT SPECIFIED

UL RECOGNIZED

BT136S-600F,118

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

25 mA

GULL WING

RECTANGULAR

1

.5 mA

500 uA

2

TRIACs

125 Cel

TIN

4 A

R-PSSO-G2

1

1.5 V

Not Qualified

600 V

50 V/us

15 mA

TO-252

e3

BT137-600,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

8 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

100 V/us

20 mA

SENSITIVE GATE

TO-220AB

e3

BT137-600G,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

8 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

10 V/us

200 V/us

40 mA

TO-220AB

e3

BT138-600,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

12 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

100 V/us

30 mA

TO-220AB

e3

BTA06T-600CWRG

STMicroelectronics

SNUBBERLESS TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

1 mA

3

TRIACs

125 Cel

-40 Cel

6 A

R-PSFM-T3

1.3 V

Not Qualified

600 V

750 V/us

35 mA

TO-220AB

NOT SPECIFIED

NOT SPECIFIED

Q6040J7TP

Littelfuse

ALTERNISTOR TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

100 mA

SOLDER LUG

RECTANGULAR

1

5 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

40 A

R-PSFM-D3

2

2 V

Not Qualified

600 V

50 V/us

625 V/us

100 mA

e3

40

260

UL RECOGNIZED

T835-600G

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

GULL WING

RECTANGULAR

1

.005 mA

2

TRIACs

125 Cel

-40 Cel

MATTE TIN

8 A

R-PSSO-G2

1.3 V

Not Qualified

600 V

4.5 V/us

500 V/us

35 mA

e3

Z0409MF

STMicroelectronics

4 QUADRANT LOGIC LEVEL TRIAC

IN-LINE

NO

SINGLE

SINGLE

PLASTIC/EPOXY

10 mA

THROUGH-HOLE

RECTANGULAR

1

.2 mA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

.95 A

R-PSIP-T3

2 V

Not Qualified

600 V

30 V/us

15 mA

SENSITIVE GATE

e3

ACST1210-7G

STMicroelectronics

TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

PLASTIC/EPOXY

10 mA

GULL WING

RECTANGULAR

1

1.5 mA

2

TRIACs

125 Cel

-40 Cel

Matte Tin (Sn) - annealed

12 A

R-PSSO-G2

1

1 V

Not Qualified

700 V

200 V/us

30 mA

HIGH RELIABILITY

e3

30

245

ACST8-8CG-TR

STMicroelectronics

SNUBBERLESS TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

30 mA

GULL WING

RECTANGULAR

1

1 mA

2

TRIACs

125 Cel

-40 Cel

Matte Tin (Sn)

8 A

R-PSSO-G2

1.5 V

Not Qualified

800 V

750 V/us

40 mA

e3

BT137-800,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

8 A

R-PSFM-T3

1.5 V

Not Qualified

800 V

100 V/us

20 mA

SENSITIVE GATE

TO-220AB

e3

BT137-800E,127

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

10 mA

THROUGH-HOLE

RECTANGULAR

1

.5 mA

500 uA

3

TRIACs

125 Cel

TIN

8 A

R-PSFM-T3

1.5 V

Not Qualified

800 V

50 V/us

20 mA

SENSITIVE GATE

TO-220AB

e3

BT137B-800,118

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

35 mA

GULL WING

RECTANGULAR

1

.5 mA

500 uA

2

TRIACs

125 Cel

-40 Cel

TIN

8 A

R-PSSO-G2

1

1.5 V

Not Qualified

800 V

100 V/us

20 mA

TO-263AB

e3

BT137B-800F,118

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

25 mA

GULL WING

RECTANGULAR

1

.5 mA

500 uA

2

TRIACs

125 Cel

-40 Cel

TIN

8 A

R-PSSO-G2

1

1.5 V

Not Qualified

800 V

50 V/us

20 mA

TO-263AB

e3

BT137S-800G,118

NXP Semiconductors

4 QUADRANT LOGIC LEVEL TRIAC

SMALL OUTLINE

YES

SINGLE

SINGLE

MAIN TERMINAL 2

PLASTIC/EPOXY

50 mA

GULL WING

RECTANGULAR

1

.5 mA

500 uA

2

TRIACs

125 Cel

-40 Cel

TIN

8 A

R-PSSO-G2

1

1.5 V

Not Qualified

800 V

10 V/us

200 V/us

40 mA

TO-252

e3

BTA12-600BW

STMicroelectronics

SNUBBERLESS TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

50 mA

THROUGH-HOLE

RECTANGULAR

1

10 uA

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

12 A

R-PSFM-T3

1.5 V

Not Qualified

600 V

500 V/us

50 mA

TO-220AB

e3

Q4025L6TP

Littelfuse

ALTERNISTOR TRIAC

FLANGE MOUNT

NO

SINGLE

SINGLE

ISOLATED

PLASTIC/EPOXY

80 mA

THROUGH-HOLE

RECTANGULAR

1

3

TRIACs

125 Cel

-40 Cel

MATTE TIN

25 A

R-PSFM-T3

2

1.3 V

Not Qualified

400 V

30 V/us

600 V/us

100 mA

HIGH RELIABILITY

TO-220AB

e3

10

260

Triode For Alternating Current (TRIAC)

A Triode for Alternating Current (TRIAC) is a semiconductor device that is used to control the flow of electrical current in AC circuits. It is a bidirectional device that can conduct current in both directions, making it useful for AC power control applications.

TRIACs consist of a bidirectional switching element that allows for the control of AC current in both directions. They are typically used in applications where AC voltage needs to be controlled, such as in lighting control, motor speed control, and power supplies.

TRIACs work by applying a small current or voltage to the gate terminal, which allows current to flow through the device. Once the current reaches a certain level, the TRIAC turns on and conducts current in both directions until the current drops below a certain threshold, at which point the TRIAC turns off.

TRIACs are commonly used in conjunction with other components such as capacitors, inductors, and diodes to form complete electronic circuits. They are often used in power control circuits that require precise control of AC voltage or current.