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Thyristors Triacs Precautions For Common Item R07ZZ0011EJ0200 Thyristor・Triac (Previous: REJ27G0020-0100) Rev.2.00 Precautions for Use Aug.7.2019 Contents 1. Use of Thyristors ..................................................................................................................................... 2 (1) How to select current rating .............................................................................................................................. 2 (2) How to select withstanding voltage class........................................................................................................ 2 (3) Cautions on dv/dt ................................................................................................................................................ 3 (4) Cautions on di/dt ................................................................................................................................................. 3 (5) Measures to prevent false triggering ............................................................................................................... 3 2. Use of Triacs ........................................................................................................................................... 4 (1) How to select current rating .............................................................................................................................. 4 (2) How to select withstanding voltage class........................................................................................................ 4 (3) Selection of CR absorber .................................................................................................................................. 5 (4) L load and R load ............................................................................................................................................... 5 (5) Trigger mode of triacs ........................................................................................................................................ 6 (6) Gate circuit and gate current ............................................................................................................................ 7 3. Designing method of Gate Trigger Circuit .......................................................................................... 9 3.1 Determining Gate Circuit Parameters for Thyristor ......................................................................................... 9 3.2 How to Prevent False Triggering ...................................................................................................................... 10 3.3 Example of Designing Gate Trigger Circuit .................................................................................................... 11 3.4 Designing Gate Circuits for High Rate-of-Rise of On-state Current (di/dt) ................................................ 12 3.5 Current Concentration at Turn-on .................................................................................................................... 12 3.6 Gate Structure and Spread of Turn-On Area .................................................................................................. 12 4. Thermal Designing for Power Devices .............................................................................................. 13 4.1 Thermal Resistance of Heatsink ....................................................................................................................... 14 4.2 Device Setting ..................................................................................................................................................... 15 5. Cautions for mounting .......................................................................................................................... 15 5.1 Cautions for mounting ........................................................................................................................................ 15 5.2 Cautions for through-hole type devices ........................................................................................................... 16 5.3 Cautions for surface-mounted type devices ................................................................................................... 17 Revision History ............................................................................................................................................ 18 R07ZZ0011EJ0200 Rev.2.00 Page 1 of 18 Aug.7.2019 Thyristor・Triac Precautions for Use 1. Use of Thyristors (1) How to select current rating The permissible currents for thyristors are shown by the average value. Load OK TC Limits I A T(AV) ⚫ When no rush current flows (heater, solenoid load) Load current 1.3 to 1.5 current rating of thyristor Example: 1 A 1.5 = 1.5 → 2 A class thyristors Determine the size of heatsink from the catalog. ⚫ When the rush current flows (lamp, transformer, motor load) The rush current should be measured and a detailed heat Ta = 25 C calculation should be made. The current rating is roughly estimated to be twice the calculated value when no rush current flows. f = 1 Hz ⚫ When pulses are used (capacitor discharge, LC oscillation, 60 Hz short-duration application (less than 10 seconds)) PeakCurrent 1 kHz For appropriate data on thyristors used for pulse applications (gas ignition, leakage protector, CDI, strobe), contact Renesas. Pulse Width (2) How to select withstanding voltage class V VBO VDSM VDRM i 0 t VRRM VRSM VBR V = supply voltage × 2.5 to 3 DRM Selection of voltage items Withstanding Supply voltage Location of use V (V) V (V) voltage class DRM DSM 100 V line Japan (home use) 8/12 400/600 — 120 V line U.S. 100 V (120 V) line Earth leakage breaker 12/16 600/800 — /960 200 V line Japan (factory use) 12 600 — 240 V line Europe 200 V (240V) line Earth leakage breaker 16 800 960 R07ZZ0011EJ0200 Rev.2.00 Page 2 of 18 Aug.7.2019 Thyristor・Triac Precautions for Use (3) Cautions on dv/dt When voltage with large dv/dt is applied to thyristors, CR absorbers should be connected in parallel to the thyristors to suppress the dv/dt applied to the device. A capacitor of 0.047 F and a resistor of 33 are generally used for low power thyristors. For high-sensitivity and low-current thyristors, it is generally recommended to insert a resistor of 1 k between the gate and the cathode. This is also one of the measures against dv/dt. SW Load SW Opened Without a CR absorber C Power supply CR Absorber R Gate With a CR absorber circuit Voltage state - OFF t Figure1 To suppress the dv/dt by a CR absorber (4) Cautions on di/dt If the rate-of-rise di/dt of current when a thyristor is turned on exceeds the limit , the device may be damaged. In applications such as inverters and choppers which discharge large current when the thyristor is turned on, the di/dt often causes problems, so it is necessary to connect an anode reactor to suppress di/dt. (5) Measures to prevent false triggering The causes and measures of false triggering in the trigger circuit are shown in the table below. Cause Preventive measures Noise to trigger circuit (1) Stabilize the supply voltage (2) Insert a surge voltage absorber. (3) Avoid the use of noise sensitive circuits such as differentiation circuit. (4) Electromagnetic shielding with chassis etc. to avoid external noise Noise voltage induced from (1) Use shielded wires to transmit the trigger signals. wiring from the trigger circuit (2) Keep the wires as far as possible from the main circuit wires to avoid to the gate of the thyristor. electromagnetic coupling. Feedback noise from the (1) Insert an absorber for the gate (see below). main circuit (2) Insert a diode (see below). D Values for general use R : 100 to 1 k C R C : 0.01 to 0.1 F Absorber for the gate R07ZZ0011EJ0200 Rev.2.00 Page 3 of 18 Aug.7.2019 Thyristor・Triac Precautions for Use 2. Use of Triacs (1) How to select current rating The permissible currents for triacs are shown by the effective values. Load OK T C Limits IT(RMS) A ⚫ When no rush current flows (heater load) Load current 1.3 to 1.5 current rating of triac Example : 6 A 1.5 = 9 → 10 A class triacs Determine the size of heatsink from the catalog. ⚫ When the rush current flows (lamp, transformer, motor load) The rush current should be measured and a detailed heat calculation should be made. Provide us with the following values and Renesas will do the calculation for you. Ambient temperature Ta = C Peak value of rush current Ip = A, waveform if available Constant current value IT(RMS) = A Operation sequence seconds during ON, seconds during OFF Heatsink Material, size, painting, heat resistance Rth(f-a) if available. The following triacs are applicable to the loads when the rush current flows (see Table below). Load Rush current Applicable triacs 100 V • 800 W 80 A BCR10FM-12LB Incandescent lamp 100 V • 600 W 60 A BCR12FM-12LB 100 V • 500 W 50 A BCR16FM-12LB Halogen lamp 100 V • 600 W 72 A BCR16FM-12LB Microwave oven 100 V • 600 W 80 A BCR16FM-12LB General purpose 200 V • 0.75 kW 40 to 45 A BCR16FM-12LB 3-phase induction motor (2) How to select withstanding voltage class V VBO VDSM VDRM i 0 t VDRM VDSM VBO VDRM = supply voltage 2 to 3 R07ZZ0011EJ0200 Rev.2.00 Page 4 of 18 Aug.7.2019 Thyristor・Triac Precautions for Use Selection of withstanding voltage items Withstanding Supply voltage Location of use V (V) V (V) voltage item DRM DSM 100 V line Japan (home use) 100 V line 120 V line U.S. 8/12 400/600 500/720 system Reversing operation of 100 V (120 V) line capacitor
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