FLC21-135A
LOW POWER FIRE LIGHTER CIRCUIT
Application Specific Discretes A.S.D.TM
FEATURES
s
s
s
s
s
DEDICATED THYRISTOR STRUCTURE FOR CAPACITIVE DISCHARGE IGNITION OPERATION HIGH PULSE CURRENT CAPABILITY IFRM = 90A @ tp = 10S 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 120C)
1
2
3
TO-92 (Plastic)
BENEFITS
s
s
SPACE SAVING THANKS TO MONOLITHIC FUNCTION INTEGRATION HIGH RELIABILITY WITH PLANAR TECHNOLOGY
FUNCTIONAL DIAGRAM
pin 3
DESCRIPTION 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 ASDTM 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 k resistor.
Z Th
D
R
pin 1
pin 2 not connected
DEVICE TYPE FLC21-135A
APPLICATION BATTERY OPERATION
MODE Ignition
July 2003 - Ed: 6D
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FLC21-135A
ABSOLUTE RATINGS (limiting values) Symbol ITRM IFRM dI/dt Tstg Tj Tamb TL Parameter Repetitive surge peak on state current for thyristor -30C Tamb 120C Repetitive surge peak on state current for diode -30C Tamb 120C Critical rate of rise on state current -30C Tamb 120C Storage junction temperature range Maximum junction temperature Operating temperature range Maximum lead temperature for soldering during 10s 50 - 40 to + 150 125 - 30 to + 120 260 A/s C C C tp = 10s ( note 1) Value 90 Unit A
Note 1 : Test current waveform
10s
100ms
THERMAL RESISTANCE Symbol Rth(j-a) Junction to ambient Parameter Value 150 Unit C/W
ORDERING INFORMATION
FLC
FIRE LIGHTER CIRCUIT ITRM = 90A
21-
135
A
PACKAGE A: TO92
135: VRM = 135V
CIRCUIT NUMBER: SCR + diode + Zener + Resistance
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FLC21-135A
ELECTRICAL CHARACTERISTICS Symbol VRM VBO VT VF IBO IRM T Parameters Stand-off voltage Breakover voltage On-state voltage Diode forward voltage drop Breakover current Leakage current Temperature coefficient for VBO
IT V BO VRM V T VF IR M I BO V
I IF
DIODE (D) PARAMETER Symbol VF IF = 1A Test Conditions tp 500s Tj = 25C Max. Value 1.7 Unit V
THYRISTOR (Th) and ZENER (Z) PARAMETERS Value Symbol IRM VBO IBO VT T Fig. 1: Relative variation of breakover current versus junction temperature.
k = IBO(Tj) / IBO(25C)
Test conditions Min. VRM = 135V at IBO at VBO IT = 2A tp 500s Tj = 25C Tj = 125C Tj = 25C Tj = 25C Tj = 25C 140
FLC21-135A Typ. Max. 1 10 160 500 1.7 0.16
Unit A A V A V V/C
2.5
2
1.5
1
0.5
0
-20
0
20
40
60
80
100
Tj (C)
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FLC21-135A
Fig. 2: BASIC AC MAINS APPLICATION.
Ic Ic t
S1 Rs
Ds
c
Th
AC
Z D R
MAINS
Fig. 3: BASIC DC APPLICATION.
Ic Ic t
S1
DC/AC Oscillator
Ds
Rs
c
Th Z D R
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.
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.
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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 + T .( Tamb - 25 ))] k . I BO *
* : see fig 1
Fig. 4: Spark frequency versus Rs and C.
FLC21-135A
Vdc=300V, Vbo=150V, Tamb=25C
F (Hz)
50
C=1 C=1
F
30
C=2
.5F
20
C=3
C=2
.2F
.7F
.3F
10 10 12 15 18 22 27 33 39 47
Rs (k )
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.
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FLC21-135A
PACKAGE MECHANICAL DATA TO-92 (Plastic)
DIMENSIONS REF.
A a B C
Millimeters Min. Typ. Max. Min. 1.35 4.70 2.54 4.40 12.70 3.70 0.45 0.173 0.500
Inches Typ. Max. 0.053 0.185 0.100
A B C D
F
D
E
E F a
0.146 0.017
OTHER INFORMATION Type FLC21-135A Marking FLC21-135A Package TO-92 Weight 0.20 g Base qty 2500 Delivery mode Bulk
s
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
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