TCA 785 Phase Control IC TCA 785

1 Semiconductor Group1 TCA 785 This Phase Control IC is intended to Control thyristors, triacs, and transistors. The trigger pulsescan be shifted within a Phase angle between 0 and 180 . Typical applications includeconverter circuits, AC controllers and three- Phase current IC replaces the previous types TCA 780 and TCA 780 D.(top view)Pin ConfigurationPhase Control IC TCA 785Pb-free lead plating; RoHS compliant Bipolar ICFeatureslReliable recognition of zero passagelLarge application scopelMay be used as zero point switchlLSL compatiblelThree- Phase operation possible (3 ICs)lOutput current 250 mAlLarge ramp current rangelWide temperature rangePG-DIP-16-1 TypeOrdering CodePackageTCA 785Q67000-A2321PG-DIP-16-1 PinSymbolFunction1 GNDG round234Q2Q UQ2 Output 2 invertedOutput UOutput 1 inverted5 VSYNCS ynchronous voltage67IQ ZInhibitOutput Z8 VREFS tabilized voltage910R9C10 Ramp resistanceRamp capacitance11V11 Control voltage12C12 Pulse extension13 LLong pulse1415Q 1Q 2 Output 1 Output 216 VSSupply voltagePin Definitions and Functions Group2 TCA 785 Functional DescriptionThe synchronization signal is obtained via a high-ohmic resistance from the line voltage(voltageV5).

2 A zero voltage detector evaluates the zero passages and transfers them to thesynchronization synchronization register controls a ramp generator, the capacitorC10 of which is chargedby a constant current (determined byR9). If the ramp voltageV10 exceeds the Control voltageV11 (triggering angle ), a signal is processed to the logic. Dependent on the magnitude of thecontrol voltageV11, the triggering angle can be shifted within a Phase angle of 0 to 180 .For every half wave, a positive pulse of approx. 30 s duration appears at the outputs Q 1 andQ 2. The pulse duration can be prolonged up to 180 via a capacitorC12. If pin 12 is connectedto ground, pulses with a duration between and 180 will and supply the inverse signals of Q 1 and Q signal of +180 which can be used for controlling an external logic,is available at pin signal which corresponds to the NOR link of Q 1 and Q 2 is available at output Q Z (pin 7).The inhibit input can be used to disable outputs Q1, Q2 and.

3 Pin 13 can be used to extend the outputs and to full pulse length (180 ).Q 1Q 2Q 1Q 2Q 1Q 2 Block DiagramSemiconductor Group3 TCA 785 Pulse DiagramSemiconductor Group4 TCA ValuesAbsolute Maximum RatingsVSupply voltageVS current at pin 14, 15IQ 10400K/WThermal resistancesystem - airRth SA80 VVVI nhibit voltageControl voltageVoltage short-pulse circuitV6V11V13 ASynchronization input currentV5 200 200 VOutput voltage at pin 14, 15 VQVSmAOutput current at pin 2, 3, 4, 7IQ10 VOutput voltage at pin 2, 3, 4, 7 VQVS C CJunction temperatureStorage temperatureTjTstg 55150125 Operating RangeVSupply voltageVS818 HzOperating frequencyf10500 CAmbient temperatureTA 2585 Characteristics8 VS 18 V; 25 C TA 85 C;f = 50 current consumptionS1 .. S6 openV11 = 0 VC10 = 47 nF;R9 = 100 k AmVSynchronization pin 5 Input currentR2 variedOffset voltageI5 rms V530143020075Vk Control input pin 11 Control voltage rangeInput peakSemiconductor Group5 TCA 785 Characteristics (cont d)8 VS 18 V; 25 C TA 85 C;f = 50 ValuesTestCircuittyp.

4 AVmVk sRamp generatorCharge currentMax. ramp voltageSaturation voltage at capacitorRamp resistanceSawtooth return 2350300VV s A AInhibit pin 6switch-over of pin 7 Outputs disabledOutputs enabledSignal transition timeInput currentV6 = 8 VInput currentV6 = VV6 LV6 HtrI6 H A ALong pulse switch-overpin 13switch-over of S8 Short pulse at outputLong pulse at outputInput currentV13 = 8 VInput currentV13 = VV13 HV13 LI13 H I13 ofI10R9 = = 12 V;C10 = 47 nFDeviation of I10R9 = = 8 V to 18 VDeviation of the ramp voltagebetween 2 followinghalf-waves,VS = V10 max 5 2011 1520 AVOutputs pin 2, 3, 4, 7 Reverse currentVQ =VSSaturation voltageIQ = 2 Group6 TCA 785 Characteristics (cont d)8 VS 18 V; 25 C TA 85 C;f = 50 s s/nFOutputs pin 14, 15H-output voltage IQ = 250 mAL-output voltageIQ = 2 mAPulse width (short pulse)S9 openPulse width (short pulse)withC12V14/15 HV14/15 LtptpVS voltage controlReference voltageParallel connection of10 ICs possibleTC of reference voltageVREF 10 10 4 Semiconductor Group7 TCA 785 Pulse Extension versus TemperatureRamp capacitanceTriggering pointCharge currentThe minimum and maximum values ofI10are to be observedminmaxtTr =C10500 pF1 F1)2)I10 =2)V11 R9 C10 VREF KVREF KR9V10 max =VS 2 VV10 =VREF K tR9 C102)Ramp voltageApplication Hints for External Components1)Attention to flyback times2)K = 20 %Semiconductor Group8 TCA 785 Supply Current versus Supply VoltageOutput Voltage measured to +VSSemiconductor Group9 TCA 785 Test Circuit 1It is necessary for all measurements to adjust the ramp withthe aid ofC10 andR9 in the way that 3 V Vramp max VS 2 = 47 nF; 18 V:R9 = 47 k.

5 8 V:R9 = 120 k Semiconductor Group10 TCA 785 Test Circuit 2 Test Circuit 3 The remaining pins are connected as in test circuit 1 The remaining pins are connected as in test circuit 1 Semiconductor Group11 TCA 785 Test Circuit 4 Remaining pins are connected as in test circuit 1 The 10 F capacitor at pin 5 serves only for test purposesTest Circuit 5 Test Circuit 6 Semiconductor Group12 TCA 785 Inhibit 6 Long Pulse 13 Pulse Extension 12 Reference Voltage 8 Semiconductor Group13 TCA 785A Phase Control with a directly controlled triac is shown in the figure. The triggering angle ofthe triac can be adjusted continuously between 0 and 180 with the aid of an externalpotentiometer. During the positive half-wave of the line voltage, the triac receives a positivegate pulse from the IC output pin 15. During the negative half-wave, it also receives a positivetrigger pulse from pin 14. The trigger pulse width is approx. 100 ExamplesTriac Control for up to 50 mA Gate Trigger CurrentSemiconductor Group14 TCA 785 Shown is the possibility to trigger two antiparalleled thyristors with one IC TCA 785.

6 The triggerpulse can be shifted continuously within a Phase angle between 0 and 180 by means of apotentiometer. During the negative line half-wave the trigger pulse of pin 14 is fed to therelevant thyristor via a trigger pulse transformer. During the positive line half-wave, the gate ofthe second thyristor is triggered by a trigger pulse transformer at pin Controlled AC Power ControllerCircuit for Two High-Power ThyristorsSemiconductor Group15 TCA 785 Half-Controlled Single- Phase Bridge Circuit with Trigger Pulse Transformer and DirectControl for Low-Power ThyristorsSemiconductor Group16 TCA 785 Half-Controlled Single- Phase Bridge Circuit with Two Trigger Pulse Transformers forLow-Power Thyristors