L9686MD

L9686 ® AUTOMOTIVE DIRECTION INDICATOR RELAY DRIVER IN CAR DIRECTION INDICATORS FLASH FREQUENCY DOUBLES TO INDICATE LAMP FAILURE DUMP PROTECTION ( ± 80 V) REVERSE BATTERY PROTECTION DESCRIPTION The L9686 is a two frequency oscillator particularly suitable as relay driver for flashing light control in automotive applications. The circuit may be also used for other warning lamps like "handbrake on" etc. The lamp failure detection is given by doubling the flash repetition frequency. The L9686 is supplied in minidip 8-lead and SO8 plastic packages. MINIDIP ) s t( ORDERING NUMBERS: L9686 L9686D c u d e t le BLOCK DIAGRAM ) s ( ct SO8 o r P o s b O - u d o r P e t e l o s b O September 2003 1/7 L9686 PIN CONNECTION (Top view) DEVICE GND 1 8 STARTER +VBATT 2 7 FAULT DET. OUTPUT 3 6 N.C. OSCILLATOR 4 5 OSCILLATOR D95AT175 c u d ABSOLUTE MAXIMUM RATINGS Symbol VS Parameter o s b O - Transient Peak Supply Voltage (R3 > 220Ω): Load Dump: 5ms < trise < 10ms τf Fall Time Constant = 100ms Rsource > 0.5Ω Field Decay: 5ms < tfall < 10ms, Rsource > Ω τr Rise Time Constant = 33ms Low Energy Spike: trise = 1µs, tfall = 2ms, Rsource > 10Ω Junction and Storage Temperature Range ) s ( ct Tj, Tstg e t le u d o r P e ) s t( o r P Value Unit 80 V – 80 V ± 100 V – 55 to 150 °C t e l o s b O THERMAL DATA Symbol Rth j-amb 2/7 Parameter Thermal Resistance Junction-ambient Max. SO8 Minidip Unit 180 100 °C/W L9686 ELECTRICAL CHARACTERISTICS (– 20°C < Tamb than this threshold, the relay will be on and the voltage across the circuit will maintain constant increasing the current in the protective resistor R3. This is the maximum value for operation. This value must be higher than 1 K Ohms in order to limit the current in pin 8 during dumps. A recommended value for application should be 1,5 K Ohms. The external leakage from the blinker unit to ground must be with an equivalent resistor higher than 5,6 K Ohms to avoid parasitic operation when the switch S1 is off. This temperature coefficient is usefull to compensate the drift of the external timing network (R1, C1). This threshold is calculated for a 20 m Ohm shunt. The threshold is dependant of Vbat as the bulb current. e t le 2. 3. 4. 5. ) s ( ct u d o r P e o s b O - FUNCTIONAL DESCRIPTION The circuit is designed to drive the direction indicator flasher relay. The application circuit shows the typical system configuration with the external components. Its consists of a network (R1 C1) to determine the oscillator frequency, shunt resistor (RS) to detect defective bulbs and two current limiting resistors (R2/R3) to protect the IC against load dump transients. The lightbulbs L2, L3, L4, L5, are the turn signal indicators with the dashboard-light L6. The S1 switch position is sensed across resistor R2 and Rlamp by input 8. The flashing cycle is started s b O t e l o by closing S1 : then, after a delay time td typically equal to 1.5 ms, the relay is actuated and the pin 3 goes high switching on the corresponding lamps L2, L3, (or L4, L5). These lamps will flash at the oscillator frequency not depending on the battery voltage value (8 - 18 V). The flashing cycle stops and the circuit is reset to the initial position when the switch S1 is open. The lamp failure detection function senses the current through the shunt resistor RS. When one of the lightbulbs is defective the voltage drop across RS is reduced to a half and the failure is indicated by doubling the flashing frequency. 3/7 L9686 Figure 1: Application Circuit. c u d e t le ) s ( ct u d o r P e t e l o s b O 4/7 o s b O - o r P ) s t( L9686 mm inch OUTLINE AND MECHANICAL DATA DIM. MIN. A TYP. MAX. MIN. 3.32 TYP. MAX. 0.131 a1 0.51 0.020 B 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 0.012 D E 10.92 7.95 9.75 0.430 0.313 0.384 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 6.6 0.260 I 5.08 0.200 L 3.18 Z 3.81 0.125 1.52 0.150 c u d ) s ( ct o r P Minidip e t le 0.060 ) s t( o s b O - u d o r P e t e l o s b O 5/7 L9686 mm DIM. MIN. TYP. A inch MAX. MIN. TYP. a1 1.75 0.1 0.25 a2 MAX. 0.069 0.004 0.010 1.65 0.065 a3 0.65 0.85 0.026 0.033 b 0.35 0.48 0.014 0.019 b1 0.19 0.25 0.007 0.010 C 0.25 0.5 0.010 0.020 D (1) 4.8 5.0 0.189 0.197 E 5.8 6.2 0.228 0.244 c1 OUTLINE AND MECHANICAL DATA 45° (typ.) e 1.27 0.050 e3 3.81 0.150 F (1) 3.8 4.0 0.15 0.157 L 0.4 1.27 0.016 0.050 M 0.6 0.024 c u SO8 d o r P e let 8 ° (max.) S (1) D and F do not include mold flash or protrusions. Mold flash or potrusions shall not exceed 0.15mm (.006inch). ) s ( ct u d o r P e t e l o s b O 6/7 o s b O - ) s t( L9686 c u d e t le ) s ( ct ) s t( o r P o s b O - u d o r P e t e l o 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. s b O The ST logo is a registered trademark of STMicroelectronics. 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