ACS108-8SN-TR
Triac, 800 V, 800 mA, SOT-223, 1 V, 13 A, 10 mA
- Manufacturer: STMICROELECTRONICS
- Product type:
- MSL: MSL 1 - Unlimited
- SVHC: No SVHC (25-Jun-2025)
- No. of Pins: 4Pins
- Product Range: ACS/A.S.D.
- Triac Case Style: SOT-223
- Thyristor Mounting: Surface Mount
- Holding Current Max: 10mA
- On State RMS Current: 800mA
- Peak On State Voltage: 1.3V
- Gate Trigger Voltage Max: 1V
- Operating Temperature Max: 125°C
- Peak Non Repetitive Surge Current: 13A
- Peak Repetitive Off State Voltage: 800V
| Delivery and price | |
|---|---|
| Units per pack | 5000 |
| Price | 0.166 € |
| Current stock | 1000+ |
| Lead time | 30 days |
**ACS108-8SN** Datasheet ## 0.8 A - 800 V overvoltage protected AC switch (ACS™) ## **Features** **==> picture [101 x 76] intentionally omitted <==** **----- Start of picture text -----**<br> COM<br>G<br>COM<br>OUT<br>**----- End of picture text -----**<br> **==> picture [37 x 7] intentionally omitted <==** **----- Start of picture text -----**<br> SOT-223<br>**----- End of picture text -----**<br> - Enables equipment to meet IEC 61000-4-5 surge with overvoltage crowbar technology - High noise immunity against static dV/dt and IEC 61000-4-4 burst - Needs no external protection snubber or varistor - Reduces component count by up to 80% and Interfaces directly with the microcontroller - Common package tab connection supports connection of several alternating current switches on the same cooling pad - VCL gives headroom before clamping then crowbar action OUT G COM COM Common drive reference to connect to the mains OUT Output to connect to the load. G Gate input to connect to the controller through gate resistor |**Product status link**<br>~~ea~~| |---| |ACS108-8SN| |**Product summary**<br>~~See~~| |**IT(RMS)**<br>0.8 A| |**VDRM, VRRM**<br>800 V| |**IGT**<br>10 mA| ## **Applications** - Alternating current on/off static switching in appliances and industrial control systems - Driving low power high inductive or resistive loads like: - relay, valve, solenoid, dispenser - pump, fan, low power motor, door lock, air flow dumper - lamp ## **Description** The ACS108-8SN belongs to the AC switch range (built with A. S. D.[®] technology). This high performance switch can control a load of up to 0.8 A. This device switch includes an overvoltage crowbar structure to absorb the inductive turn-off energy, and a gate level shifter driver to separate the digital controller from the main switch. It is triggered with a negative gate current flowing out of the gate pin. _Note: ®: A.S.D. is a registered trademark of STMicroelectronics Note: TM: ACS is a trademark of STMicroelectronics_ **DS12893** - **Rev 2** - **August 2019** For further information contact your local STMicroelectronics sales office. www.st.com **ACS108-8SN Characteristics** **1** ## **Characteristics** **Table 1. Absolute maximum ratings (Tamb = 25 °C, unless otherwise specified)** |**Symbol**|**Parameter**||**Value**|**Unit**| |---|---|---|---|---| |IT(RMS)|On-state rms current (full sine wave), S = 5cm²|Tamb= 76 °C|0.8|A| |||Ttab= 104 °C||| |ITSM|Non repetitive surge peak on-state current<br>Tjinitial = 25 °C, (full cycle sine wave)|tp= 20 ms|13|A| |||tp= 16.7 ms|13.7|| |I2t|I2t for fuse selection|tp= 10 ms|1.1|A2s| |dI/dt|Critical rate of rise on-state current IG= 2 x IGT, tr ≤ 100 ns|f = 120 Hz, Tj= 125 °C|100|A/μs| |VPP(1)|Non repetitive line peak pulse voltage||2|kV| |PG(AV)|Average gate power dissipation|Tj= 125 °C|0.1|W| |VGM|Peak positive gate voltage|Tj= 125 °C|10|V| |IGM|Peak gate current (tp= 20 μs)|Tj= 125 °C|1|A| |Tstg|Storage temperature range||-40 to +150|°C| |Tj|Operating junction temperature range||-30 to +125|°C| _1. according to test described by standard IEC 61000-4-5, see Figure 17. Overvoltage ruggedness test circuit for resistive and inductive loads, Tamb = 25 °C (conditions equivalent to IEC 61000-4-5 standard) for conditions_ **Table 2. Electrical characteristics (Tj = 25 °C, unless otherwise specified)** |**Symbol**|**Test conditions**|**Quadrant**|**Value**|**Value**|**Unit**| |---|---|---|---|---|---| |IGT (1)|VOUT= 12 V, RL= 33 Ω|II - III|Max.|10|mA| |VGT|||Max.|1.0|V| |VGD|VOUT= VDRM, RL= 3.3 kΩ, Tj= 125 °C|II - III|Min.|0.15|V| |IH|IOUT= 100 mA||Max.|10|mA| |IL|IG= 1.2 x IGT||Max.|25|mA| |dV/dt|VOUT= 402 V, gate open, Tj= 125 °C||Min.|2000|V/μs| ||VOUT= 536 V, gate open, Tj= 125 °C|||400|| |(dI/dt)c|Without snubber (15 V/μs), Tj= 125 °C, turn-off time ≤20 ms||Min.|2|A/ms| |VCL|ICL= 0.1 mA, tp= 1 ms||Min.|850|V| _1. Minimum IGT is guaranteed at 10% of IGT max._ **DS12893** - **Rev 2** **page 2/14** **ACS108-8SN Characteristics** ## **Table 3. Static electrical characteristics** |**Symbol**|**Test conditions**|**Test conditions**|**Test conditions**|**Value**|**Unit**| |---|---|---|---|---|---| |VTM (1)|ITM= 1.1 A, tp= 500 μs|Tj= 25 °C|Max.|1.3|V| |VTO(1)|Threshold voltage|Tj= 125 °C|Max.|0.85|V| |Rd(1)|Dynamic resistance|Tj= 125 °C|Max.|300|mΩ| |IDRM<br>IRRM|VOUT= VDRM/ VRRM|Tj= 25 °C|Max.|2|µA| |||Tj= 125 °C||0.2|mA| _1. For both polarities of OUT pin referenced to COM pin_ ## **Table 4. Thermal characteristics** |**Symbol**|**Parameter**|**Parameter**|**Parameter**|**Max. value**|**Unit**| |---|---|---|---|---|---| |Rth(j-t)|Junction to tab (AC)|||25|°C/W| |Rth(j-a)|Junction to ambient|S = 5 cm²|Max.|60|| **DS12893** - **Rev 2** **page 3/14** **ACS108-8SN Characteristics (curves)** ## **1.1 Characteristics (curves)** **Figure 1. Maximum power dissipation versus rms on-state Figure 2. On-state rms current versus case temperature current** **==> picture [219 x 141] intentionally omitted <==** **----- Start of picture text -----**<br> P (W)<br>0.9<br>α = 180°<br>0.8<br>0.7<br>0.6<br>0.5<br>0.4<br>0.3<br>0.2 180°<br>0.1 IT(RMS) (A)<br>0.0<br>0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8<br>**----- End of picture text -----**<br> **==> picture [225 x 141] intentionally omitted <==** **----- Start of picture text -----**<br> IT(RMS) (A)<br>0.9<br>α = 180 °<br>0.8<br>SOT-223<br>0.7<br>0.6<br>0.5<br>0.4<br>0.3<br>0.2<br>0.1<br>TC °C<br>0.0<br>0 2 5 50 75 100 125<br>**----- End of picture text -----**<br> **==> picture [513 x 206] intentionally omitted <==** **----- Start of picture text -----**<br> Figure 3. On-state rms current versus ambient Figure 4. Relative variation of thermal impedance junction<br>temperature (free air convection) to case versus pulse duration<br>0.9 IT(RMS) (A) 1.00 K=[Zth(j-a)/Rth(j-a)]<br>α =180 ° Zth(j -a)<br>0.8<br>SOT-223<br>0.7<br>0.6<br>0.5<br>0.10<br>0.4<br>0.3 SOT-223<br>0.2<br>Single layer Printed SOT-223<br>0.1 Natural convectioncircuit board FR4 Ta °C tP (s) Copper surfacearea = 5cm²<br>0.0 0.01<br>0 25 50 75 100 125 1.0E-03 1.0E-02 1.0E-01 1.0E+00 1.0E+01 1.0E+02 1.0E+03<br>**----- End of picture text -----**<br> **DS12893** - **Rev 2** **page 4/14** **ACS108-8SN Characteristics (curves)** **==> picture [513 x 207] intentionally omitted <==** **----- Start of picture text -----**<br> Figure 5. Relative variation of holding and latching Figure 6. Relative variation of IGT and VGT versus junction<br>current versus junction temperature temperature<br>IH, IL [T j] / IH, IL [T j=25° C] IGT, VGT [T j] / IGT, VGT, [Tj=25 °C]<br>3.0 3.5<br>2.5 3.0 IGT Q2<br>IL<br>2.5 IGT Q3<br>2.0<br>2.0<br>1.5 IH<br>1.5<br>1.0<br>1.0 VGT Q2-Q3<br>0.5<br>0.5<br>Tj(°C) Tj(°C)<br>0.0 0.0<br>-50 -25 0 25 50 75 100 125 -50 -25 0 2 5 50 75 100 125<br>**----- End of picture text -----**<br> **==> picture [513 x 205] intentionally omitted <==** **----- Start of picture text -----**<br> Figure 7. Surge peak on-state current versus number of Figure 8. Non repetitive surge peak on-state current for a<br>cycles sinusoidal pulse<br>ITSM(A)<br>14 ITSM(A)<br>1.E+03<br>13 Sinusoidal pulse,<br>12 t=20ms tp < 10 ms<br>11 ITSM Tj initial = 25 °C<br>10 One cycle 1.E+02<br>Non repetitive<br>9 Tj initial=25 °C<br>8<br>7 SOT-223 1.E+01<br>6 TRepetitivetab = 104°C<br>5<br>4<br>1.E+00<br>3<br>2<br>1 Number of cycles t p(ms)<br>0 1.E-01<br>0.01 0.10 1.00 10.00<br>1 10 100 1000<br>**----- End of picture text -----**<br> **Figure 9. On-state characteristics (maximum values)** **Figure 10. Relative variation of critical rate of decrease of main current versus junction temperature** **==> picture [222 x 138] intentionally omitted <==** **----- Start of picture text -----**<br> 100.00<br>10.00<br>1.00<br>Tj=125 °C<br>Tj=25 °C Tj max.:<br>Vto= 0.85 V<br>VTM(V) Rd= 300 mΩ<br>0.10<br>0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5<br>ITM(A)<br>**----- End of picture text -----**<br> **==> picture [224 x 130] intentionally omitted <==** **----- Start of picture text -----**<br> (dI/dt) c [T ] / (dI/dt)j c [T =125 °C]j<br>2.5<br>2.0<br>1.5<br>1.0<br>0.5<br>Tj (°C)<br>0.0<br>25 35 45 55 65 75 85 95 105 115 125<br>**----- End of picture text -----**<br> **DS12893** - **Rev 2** **page 5/14** **ACS108-8SN Characteristics (curves)** **==> picture [513 x 216] intentionally omitted <==** **----- Start of picture text -----**<br> Figure 11. Relative variation of static dV/dt immunity<br>Figure 12. Relative variation of leakage current versus<br>versus junction temperature (typical values above 5<br>junction temperature<br>kV/µs)<br>IDRM/IRRM [Tj;V DRM/VRRM]/IDRM/IRRM [[Tj=125°C;800V]]<br>1.0E+00<br>5<br>VD=VR=536V<br>4<br>1.0E-01 VDRM=VRRM=800 V<br>3 VDRM=VRRM=600 V<br>2<br>1.0E-02<br>1<br>Tj(°C) Tj(°C)<br>1.0E-03<br>0<br>25 50 75 100 125<br>25 50 75 100 125<br>dV/dt [ T j] / dV/dt [ T j=125°C]<br>**----- End of picture text -----**<br> **Figure 13. Relative variation of critical rate of decrease of Figure 14. Thermal resistance junction to ambient versus main current (di/dt)c versus (dV/dt)c copper surface under tab** **==> picture [478 x 142] intentionally omitted <==** **----- Start of picture text -----**<br> 5.0 140<br>Tj =125 °C Printed circuit board FR4<br>4.5 copper thickness = 35 µm SOT-223<br>120<br>4.0<br>3.5 100<br>3.0<br>80<br>2.5<br>2.0 60<br>1.5 40<br>1.0<br>20<br>0.5 SCU(cm²)<br>(dV/dt) c (V/µs)<br>0.0 0<br>0.1 1.0 10.0 100.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0<br>(dI/dt) c [ (dV/dt) c ] / Specified(dI/dt)c Rth(j-a)(°C/W)<br>**----- End of picture text -----**<br> **DS12893** - **Rev 2** **page 6/14** **ACS108-8SN Alternating current mains switch - basic application** ## **2 Alternating current mains switch - basic application** The ACS108 switch is triggered by a negative gate current flowing from the gate pin G. The switch can be driven directly by the digital controller through a resistor as shown in Figure 15. Typical application schematic Thanks to its overvoltage protection and turn-off commutation performance, the ACS108 switch can drive a small power high inductive load with neither varistor nor additional turn-off snubber. **Figure 15. Typical application schematic** **==> picture [352 x 267] intentionally omitted <==** **----- Start of picture text -----**<br> Lamp Motor Solenoid<br>M<br>AC Mains<br>OUT<br>ACS108<br>Vss<br>Rg = 220 Ohm<br>MCU<br>GATE<br>Vdd<br>COM<br>**----- End of picture text -----**<br> **==> picture [43 x 42] intentionally omitted <==** ## **2.1 Protection against overvoltage: the best choice is ACS** In comparison with standard Triacs the ACS108 is over-voltage self-protected, as specified by the parameter VCL. This feature is useful in two operating conditions: in case of turn-off of very inductive load, and in case of surge voltage that can occur on the electrical network. ## **2.1.1 High inductive load switch-off: turn-off overvoltage clamping** With high inductive and low rms current loads the rate of decrease of the current is very low. An overvoltage can occur when the gate current is removed and the OUT current is lower than IH. As shown in Figure 16. Switching off of a high inductive load - typical clamping capability of ACS108 (Tamb = 25 °C), at the end of the last conduction half-cycle, the load current decreases ① . The load current reaches the holding current level IH ② , and the ACS turns off ③ . The water valve, as an inductive load (up to 15 H), reacts as a current generator and an overvoltage is created, which is clamped by the ACS ④ . The current flows through the ACS avalanche and decreases linearly to zero. During this time, the voltage across the switch is limited to the clamping voltage VCL. The energy stored in the inductance of the load is dissipated in the clamping section that is **DS12893** - **Rev 2** **page 7/14** **ACS108-8SN** **Protection against overvoltage: the best choice is ACS** designed for this purpose. When the energy has been dissipated, the ACS voltage falls back to the mains voltage value (230 V rms, 50 Hz) ⑤. **Figure 16. Switching off of a high inductive load - typical clamping capability of ACS108 (Tamb = 25 °C)** ## **2.1.2 Alternating current mains transient voltage ruggedness** The ACS108 switch is able to withstand safely the AC mains transients either by clamping the low energy spikes or by breaking-over when subjected to high energy shocks, even with high turn-on current rises. The test circuit shown in Figure 17. Overvoltage ruggedness test circuit for resistive and inductive loads, Tamb = 25 °C (conditions equivalent to IEC 61000-4-5 standard) is representative of the final ACS108 application, and is also used to test the AC switch according to the IEC 61000-4-5 standard conditions. Thanks to the load limiting the current, the ACS108 switch withstands the voltage spikes up to 2 kV above the peak mains voltage. The protection is based on an overvoltage crowbar technology. Actually, the ACS108 breaks over safely as shown in Figure 18. Typical current and voltage waveforms across the ACS108 (+2 kV surge, IEC 61000-4-5 standard). The ACS108 recovers its blocking voltage capability after the surge (switch off back at the next zero crossing of the current). Such non-repetitive tests can be done 10 times on each AC mains voltage polarity. **DS12893** - **Rev 2** **page 8/14** **ACS108-8SN** **Protection against overvoltage: the best choice is ACS** **Figure 17. Overvoltage ruggedness test circuit for resistive and inductive loads, Tamb = 25 °C (conditions equivalent to IEC 61000-4-5 standard)** **==> picture [373 x 269] intentionally omitted <==** **----- Start of picture text -----**<br> + 2kV Surge generator<br>Rgenerator<br>Filtering unit Cc Model of the load<br>R = 150 Ω L = 5 μH<br>[ } OUT<br>ACS108<br>GATE<br>Rg = 220 Ω COM<br>AC mains 230 V RMS, 50 Hz<br>**----- End of picture text -----**<br> **Figure 18. Typical current and voltage waveforms across the ACS108 (+2 kV surge, IEC 61000-4-5 standard)** **DS12893** - **Rev 2** **page 9/14** **ACS108-8SN Package information** **3 Package information** In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ECOPACK is an ST trademark. ## **3.1** ## **SOT-223 package information** - Epoxy meets UL94, V0 - Lead free plating + halogen-free molding resin ## **Figure 19. SOT-223 package outline** **==> picture [346 x 306] intentionally omitted <==** **----- Start of picture text -----**<br> A V c<br>A1<br>B<br>e1<br>D<br>B1<br>4<br>H E<br>1 2 3<br>e<br>**----- End of picture text -----**<br> **DS12893** - **Rev 2** **page 10/14** **ACS108-8SN SOT-223 package information** **Table 5. SOT-223 package mechanical data** ||**Dimensions**|**Dimensions**|**Dimensions**|**Dimensions**|**Dimensions**|**Dimensions**| |---|---|---|---|---|---|---| |**Ref.**|**Millimeters**|||**Inches(1)**||| ||**Min.**|**Typ.**|**Max.**|**Min.**|**Typ.**|**Max.**| |A|||1.80|||0.0709| |A1||0.02|0.10||0.0008|0.0039| |B|0.60|0.70|0.85|0.024|0.0276|0.0335| |B1|2.90|3.00|3.15|0.114|0.1181|0.1240| |c|0.24|0.26|0.35|0.009|0.0102|0.0138| |D|6.30|6.50|6.70|0.248|0.2559|0.2638| |e||2.3|||0.0906|| |e1||4.6|||0.1811|| |E|3.30|3.50|3.70|0.130|0.1378|0.1457| |H|6.70|7.00|7.30|0.264|0.2756|0.2874| |V|10° max.|||||| _1. Inches only for reference_ ## **Figure 20. SOT-223 footprint (dimensions in mm)** **==> picture [160 x 155] intentionally omitted <==** **----- Start of picture text -----**<br> 3.25<br>1.32<br>5.16 7.80<br>1.32<br>2.30 0.95<br>**----- End of picture text -----**<br> **DS12893** - **Rev 2** **page 11/14** **ACS108-8SN Ordering information** **4** ## **Ordering information** ## **Figure 21. Ordering information scheme** **==> picture [388 x 264] intentionally omitted <==** **----- Start of picture text -----**<br> ACS 1 08 - 8 S N -TR<br>AC switch series<br>Number of switches<br>Current<br>08 = 0.8 A rms<br>Voltage<br>8 = 800 V<br>Gate current<br>S = 10 mA<br>Package<br>N = SOT-223<br>Packing<br>TR = Tape and reel 7” (SOT-223, 1000 pieces)<br>**----- End of picture text -----**<br> **Table 6. Ordering information** |**Order code**|**Marking**|**Package**|**Weight**|**Base qty.**|**Packing mode**| |---|---|---|---|---|---| |ACS108-8SN-TR|ACS 108 8S(1)|SOT-223|0.11 g|1000|Tape and reel| _1. first row = ACS, second row = 108, third row = 8S_ **DS12893** - **Rev 2** **page 12/14** **ACS108-8SN** ## **Revision history** **Table 7. Document revision history** |**Date**|**Version**|**Changes**| |---|---|---| |07-Feb-2019|1|Initial release.| |08-Aug-2019|2|UpdatedSection Product status link / summary.| **DS12893** - **Rev 2** **page 13/14** **ACS108-8SN** ## **IMPORTANT NOTICE – PLEASE READ CAREFULLY** STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, enhancements, modifications, and improvements to ST products and/or to this document at any time without notice. Purchasers should obtain the latest relevant information on ST products before placing orders. ST products are sold pursuant to ST’s terms and conditions of sale in place at the time of order acknowledgement. Purchasers are solely responsible for the choice, selection, and use of ST products and ST assumes no liability for application assistance or the design of Purchasers’ products. No license, express or implied, to any intellectual property right is granted by ST herein. Resale of ST products with provisions different from the information set forth herein shall void any warranty granted by ST for such product. ST and the ST logo are trademarks of ST. For additional information about ST trademarks, please refer to www.st.com/trademarks. All other product or service names are the property of their respective owners. Information in this document supersedes and replaces information previously supplied in any prior versions of this document. © 2019 STMicroelectronics – All rights reserved **DS12893** - **Rev 2** **page 14/14**
Updated at April 26, 2026
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