1/6 application specific discretes a.s.d.? flc21 series ? september 2000 - ed: 5d low power fire lighter circuit the flc21 series 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 sts 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 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: 2k w resistor. description z r d th pin 3 pin 1 pin 2 not connected functional diagram to-92 (plastic) n dedicated thyristor structure for capacitive discharge ignition operation n high pulse current capability i frm =90a @ tp=10 m s n ac or dc operation capability with supply from the ac mains or a dc battery n fast turn-on operation n designed for high ambient temperature (up to 120c) features 1 2 3 n space saving thanks to monolithic function integration n high reliability with planar technology benefits device type application mode FLC21-135A battery operation ignition flc21-65a 100v mains ignition
flc21 series 2/6 symbol parameter value unit rth(j-a) junction to ambient 150 c/w thermal resistance flc 2 1 135 a - fire lighter circuit circuit number: scr + diode + zener + resistance itrm = 90a package a: to92 135: v = 135v 65: v = 65v rm rm ordering information symbol parameter value unit i trm repetitive surge peak on state current for thyristor -30c tamb 120c tp=10 m s ( note 1) 90 a i frm repetitive surge peak on state current for diode -30c tamb 120c di/dt critical rate of rise on state current -30c tamb 120c 50 a/ m s tstg tj storage junction temperature range maximum junction temperature -40to+150 125 c tamb operating temperature range -30to+120 c t l maximum lead temperature for soldering during 10s 260 c note 1 : test current waveform absolute ratings (limiting values) 100ms 10s
flc21 series 3/6 symbol parameters v rm stand-off voltage v bo breakover voltage v t on-state voltage v f diode forward voltage drop i bo breakover current i rm leakage current a t temperature coefficient for v bo electrical characteristics i i f v f v t i rm i bo i t v v bo v rm symbol test conditions value unit v f i f =1a tp 500s tj = 25c max. 1.7 v diode (d) parameter symbol test conditions value unit flc21-65a FLC21-135A min. typ. max. min. typ. max. i rm v rm = 65v for flc21-65a tj = 25c 1 1 m a v rm = 135v for FLC21-135A tj = 125c 10 10 m a v bo at i bo tj = 25c 70 80 140 160 v i bo at v bo tj = 25c 500 500 m a v t i t =2a tp 500s tj = 25c 1.7 1.7 v a t 0.07 0.16 v/c thyristor (th) and zener (z) parameters -20 0 20 40 60 80 100 0 0.5 1 1.5 2 2.5 tj (c) k = i (tj) / i (25c) bo bo fig. 1: relative variation of breakover current versus junction temperature.
flc21 series 4/6 rs s 1 ds c d th z r ic ac mains ic t fig. 2: basic ac mains application . 1/ ignition mode phase 1 the ac voltage is rectified by the diode ds. the ignition energy is supplied by the mains and stored into the capacitor c. s 1 c d th z r ic ic t ds dc/ac oscillator rs fig. 3: basic dc application . phase 2 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.
flc21 series 5/6 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 v bo and the current i bo of the flc are maximum. the maximum rs value is equal to: rs vvtt ki ac bo amb bo max ( min. ) [ max .( .( ))] .* = -+- 2125 a * : see fig 1 10 12 15 18 22 27 33 39 47 10 20 30 50 f (hz) rs (k ) w vac=100vrms, vbo=75v, tamb=25c c=1 f m c=1 f m c=1.5 f m c=1.5 f m c=2.2 f m c=2.7 f m c=3.3 f m flc21-65a 10 12 15 18 22 27 33 39 47 10 20 30 50 FLC21-135A vdc=300v, vbo=150v, tamb=25c f (hz) rs (k ) w c=3.3 f m c=2.7 f m c=2.2 f m c=1 f m c=1 f m c=1.5 f m c=1.5 f m fig. 4: spark frequency versus rs and c. 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.
flc21 series 6/6 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 ap- proval of stmicroelectronics. the st logo is a registered trademark of stmicroelectronics ? 2000 stmicroelectronics - printed in italy - all rights reserved. stmicroelectronics group of companies australia - brazil - china - finland - france - germany - hong kong - india - italy - japan - malaysia malta - morocco - singapore - spain - sweden - switzerland - united kingdom - u.s.a. http://www.st.com package mechanical data to-92 (plastic) d f a e b a c ref. dimensions millimeters inches min. typ. max. min. typ. max. a 1.35 0.053 b 4.70 0.185 c 2.54 0.100 d 4.40 0.173 e 12.70 0.500 f 3.70 0.146 a 0.45 0.017 type marking package weight base qty delivery mode flc21- 65a flc21-65a to-92 0.20 g 2500 bulk FLC21-135A FLC21-135A to-92 0.20 g 2500 bulk n epoxy meets ul94, vo at 1/8" other information
|
