FLC21-135A ® Application Specific Discretes A.S.D.™ LOW POWER FIRE LIGHTER CIRCUIT FEATURES ■ ■ ■ ■ ■ DEDICATED THYRISTOR STRUCTURE FOR CAPACITIVE DISCHARGE IGNITION OPERATION HIGH PULSE CURRENT CAPABILITY IFRM = 90A @ tp = 10µS AC OR DC OPERATION CAPABILITY WITH SUPPLY FROM THE AC MAINS OR A DC BATTERY FAST TURN-ON OPERATION DESIGNED FOR HIGH AMBIENT TEMPERATURE (up to 120°C) 1 2 3 TO-92 (Plastic) BENEFITS ■ ■ SPACE SAVING THANKS TO MONOLITHIC FUNCTION INTEGRATION HIGH RELIABILITY WITH PLANAR TECHNOLOGY FUNCTIONAL DIAGRAM pin 3 DESCRIPTION Z The FLC21-135A has been especially developed for capacitance discharge operation. The main applications are: fuel ignitors, fuel or gas heaters, gas ranges, cooker tops, barbecues, water heaters, HVACs, portable ignitors, insect killers. Based on ST’s ASD™ technology, it provides a fully integrated function, with high performance and reliability levels, adapted to severe and hot temperature environment. The typical supply of the FLC21-135A fire lighter circuit is a DC battery or the AC mains. Th: Thyristor for the switching operation. Z: Zener diode to set the igniting threshold voltage. D: Diode for the reverse conduction. R: 2 kΩ resistor. July 2003 - Ed: 6D Th D R pin 1 pin 2 not connected DEVICE TYPE FLC21-135A APPLICATION BATTERY OPERATION MODE Ignition 1/6 FLC21-135A ABSOLUTE RATINGS (limiting values) Symbol Parameter Value Unit 90 A 50 A/µs ITRM Repetitive surge peak on state current for thyristor -30°C ≤ Tamb ≤ 120°C IFRM Repetitive surge peak on state current for diode -30°C ≤ Tamb ≤ 120°C dI/dt Critical rate of rise on state current -30°C ≤ Tamb ≤ 120°C Tstg Tj Storage junction temperature range Maximum junction temperature - 40 to + 150 125 °C Operating temperature range - 30 to + 120 °C 260 °C Tamb TL tp = 10µs ( note 1) Maximum lead temperature for soldering during 10s Note 1 : Test current waveform 10µs 100ms THERMAL RESISTANCE Symbol Rth(j-a) Parameter Junction to ambient Value Unit 150 °C/W ORDERING INFORMATION FLC 2 1 - 135 A PACKAGE A: TO92 FIRE LIGHTER CIRCUIT ITRM = 90A 135: VRM = 135V CIRCUIT NUMBER: SCR + diode + Zener + Resistance 2/6 FLC21-135A I IF ELECTRICAL CHARACTERISTICS Symbol Parameters VRM Stand-off voltage VBO Breakover voltage V BO VT On-state voltage VF Diode forward voltage drop IBO Breakover current IRM Leakage current αT Temperature coefficient for VBO V T VRM VF V IRM I BO IT DIODE (D) PARAMETER Symbol VF Test Conditions tp ≤ 500µs IF = 1A Tj = 25°C Value Unit 1.7 V Max. THYRISTOR (Th) and ZENER (Z) PARAMETERS Value Symbol Test conditions FLC21-135A Min. IRM VRM = 135V Typ. Unit Max. Tj = 25°C 1 µA Tj = 125°C 10 µA 160 V VBO at IBO Tj = 25°C IBO at VBO Tj = 25°C 500 µA VT IT = 2A Tj = 25°C 1.7 V tp ≤ 500µs αT 140 0.16 V/°C Fig. 1: Relative variation of breakover current versus junction temperature. k = IBO(Tj) / IBO(25°C) 2.5 2 1.5 1 0.5 0 -20 0 20 40 60 80 100 Tj (°C) 3/6 FLC21-135A Fig. 2: BASIC AC MAINS APPLICATION. Ic Ic t S1 c Ds Rs Th Z AC D MAINS R Fig. 3: BASIC DC APPLICATION. Ic Ic t Ds S1 c Rs DC/AC Oscillator Th Z D R 1/ IGNITION MODE PHASE 2 PHASE 1 At the end of the phase 1, the voltage across the capacitor C reaches the avalanche threshold of the Zener diode Z. Then, a current flows through this Zener diode into the gate of the thyristor Th which is triggered. The thyristor turn-on generates an alternating current through the capacitor C. Its positive parts flow through the capacitor C, the primary of the HV transformer and the thyristor Th. Its negative parts of the current flow through C, D and the primary of the H.V transformer. The AC voltage is rectified by the diode Ds. The ignition energy is supplied by the mains and stored into the capacitor C. 4/6 FLC21-135A RS RESISTANCE CALCULATION The Rs resistance allows, in addition with the capacitance C, the spark frequency to be adjusted and the current supplied by the mains to be limited. This resistance allows the thyristor triggering in any requested cases. In the worst case scenario, the system must fire when the a.c. line voltage is minimum while the breakdown voltage VBO and the current IBO of the FLC are maximum. The maximum Rs value is equal to: Rs max = (V AC min. 2 ) − [V BO max .(1 + α T .( Tamb − 25 ))] k . I BO * * : see fig 1 Fig. 4: Spark frequency versus Rs and C. FLC21-135A F (Hz) Vdc=300V, Vbo=150V, Tamb=25°C 50 C=1 µF C=1 .5µF 30 C=2 .2µF C=2 20 .7µF C=3 .3µF 10 10 12 15 18 22 27 33 39 47 Rs (k Ω ) The couple Rs/C can be chosen with the previous curve. Keep in mind the Rs maximum limit for which the system would not work when the AC mains is minimum. 5/6 FLC21-135A PACKAGE MECHANICAL DATA TO-92 (Plastic) DIMENSIONS REF. Millimeters Min. A a A Typ. Max. Min. Typ. Max. 1.35 0.053 B B C 4.70 C F D E Inches 0.185 2.54 0.100 D 4.40 0.173 E 12.70 0.500 F 3.70 0.146 a 0.45 0.017 OTHER INFORMATION ■ Type Marking Package Weight Base qty Delivery mode FLC21-135A FLC21-135A TO-92 0.20 g 2500 Bulk Epoxy meets UL94, VO at 1/8" Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics © 2003 STMicroelectronics - Printed in Italy - All rights reserved. STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - Finland - France - Germany Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Singapore Spain - Sweden - Switzerland - United Kingdom - United States. http://www.st.com 6/6