BT139-800 is 16Amp rating Triac. Its Gate trigger voltage is 0.7V and reverse voltage rating is 800V. Its operational temperature range is from -40 to 150 °C. It comes in a 3 pin TO-220AB package.

Specifications:

•  TRIAC, 16A, 800V, TO-220

•  Peak Repetitive Off-State Voltage, Vdrm: 800V

•  On State RMS Current IT(rms): 16A

•  Peak Non Rep Surge Current Itsm 50Hz: 155A

•  Gate Trigger Voltage Max Vgt: 0.7V

•  Peak Gate Power: 5W

•  Operating Temperature Range: -40°C to +150°C

•  No. of Pins: 3

•  Current Itsm: 140A

•  Current Itsm @ 60Hz: 170A

•  Current t2+g-: 35mA

•  Current t2-g+: 70mA

•  Current t2-g-: 35mA

•  Device Marking: BT139-800

•  Gate Trigger Current Igt (Q1) t2+g+: 35mA

•  Gate Trigger Current Max, Igt: 35mA

•  Holding Current Max Ih: 45mA

•  Package / Case: TO-220AB

•  Repetitive Reverse Voltage Vrrm Max: 800V

•  Termination Type: Through Hole

•  Thyristor Type: Triac

  Datasheet:

         http://www.nxp.com/documents/data_sheet/BT139-800.pdf