CS1108 Single Lamp Driver IC This ASIC provides up to 350 mA of drive current for powering bulbs. The typical application for this part is for use in airbag systems using a type 194 bulb. On–chip diagnostics provide open circuit and short circuit detection in the output on mode. In addition, the output driver will turn on (sink current) when VCC is low. Fault is an active–low output which reports in the output–on mode. Internal pull–up circuitry is provided to ensure the output pin turns on when the Control pin is floating. http://onsemi.com 8 1 Features • Fault Detection – Open Circuit – Short Circuit – Overtemperature • VCC Sense: Output Turns On with Loss of VCC • Low Standby Current • Internally Fused Leads in SO–8 Package SO–8 DF SUFFIX CASE 751 PIN CONNECTIONS AND MARKING DIAGRAM Output VCC 8 1108 ALYW VCC Fault 1 Control VCC(SENSE) ISOURCE GND GND GND GND Output Drive & Bias A WL, L YY, Y WW, W Control Overtemp Shutdown = Assembly Location = Wafer Lot = Year = Work Week Duty cycle during short circuit ORDERING INFORMATION Device + – Fault – + GND GND GND Short Circuit Detect Package Shipping CS1108EDF8 SO–8 95 Units/Rail CS1108EDFR8 SO–8 2500 Tape & Reel Open Circuit Detect GND Figure 1. Block Diagram Semiconductor Components Industries, LLC, 2001 April, 2001 – Rev. 6 1 Publication Order Number: CS1108/D CS1108 MAXIMUM RATINGS* Rating Value Unit Storage Temperature –65 to +150 °C VCC, Fault, Control –0.5 to 6.0 V 2.0 kV 40 V 230 peak °C ESD Capability (Human Body Model) Peak Transient Voltage (output off mode, output pin only) (26 V Load Dump @ 14 V VBAT) Lead Temperature Soldering: Reflow: (SMD styles only) (Note 1) 1. 60 second maximum above 183°C. *The maximum package power dissipation must be observed. ELECTRICAL CHARACTERISTICS (4.75 ≤ VCC ≤ 5.25 V, –40°C ≤ TA ≤ 85°C, –40°C ≤ TJ ≤ 150°C; unless otherwise specified.) Characteristic Test Conditions Min Typ Max Unit Supply Requirements VCC Quiescent Current Output ON – 3.0 6.0 mA VCC Quiescent Current Output OFF – 100 250 µA Leakage Current VBAT = 14 V – 16 100 µA Saturation Voltage IOUTPUT = 350 mA IOUTPUT = 180 mA – – 1.1 0.9 1.5 1.3 V V VOUTPUT (self–bias) VCC < 4.5 V, IOUTPUT < 200 mA – – 3.5 V Output Current Sense Short Circuit Current – 350 500 650 mA Open Circuit Current Output in the ON state 20 40 60 mA Input Voltage Logic = High Logic = Low 2.0 – – – – 0.8 V V Input Current Logic = VCC Logic = 0 V – –50 20 –20 40 – µA µA – 0.24 0.40 V Control–Input Fault Output – (Open Collector) Output Low Voltage IFAULT = 250 µA (sink) Overtemperature Shutdown TJ Output Disable Threshold (Guaranteed by Design) 150 180 – °C TJ Hysteresis (Guaranteed by Design) 5.0 – – °C Note: A fault signal will be shown (at the fault pin) during inrush as the short circuit threshold is exceeded. PACKAGE PIN DESCRIPTION PACKAGE PIN # 8 Lead SO Narrow PIN SYMBOL 1 Output 2 VCC 5.0 V regulated supply input. 3 Fault Open collector diagnostic output low during open load, short circuit and overtemperature conditions. 4 Control TTL compatible input. 5, 6, 7, 8 Ground Signal ground. FUNCTION Open collector output. http://onsemi.com 2 CS1108 CIRCUIT DESCRIPTION Typical lamps have a low resistance when off and the current will exceed the current limit threshold during the initial inrush period. During this inrush time, the IC will be operating in the duty cycle mode. Due to characteristics of lamps in this mode, they may appear dimly lit. This condition will persist for a breif time until the lamp resistance has increased enough to reduce it’s current below the threshold. Once this occurs the lamp will appear at full brightness. During the inrush period the Fault pin will be forced low indicating that duty cycle mode is in operation. Thermal protection has been designed into this IC. Should duty cycle mode operate for an extended amount of time and the power limitations of the IC are exceeded the IC die temperature will rise. Once the die temperature reaches the thermal temperature limit, the internal cicuitry will shutoff the output and the lamp will turn off. Once the die temperature lowers below the thermal threshold, the output will be allowed to turn back on. The CS1108 lamp driver IC provides up to 350 mA of drive current in a low–side configuration. The Output driver pin is controlled through the TTL compatible Control input pin. A high condition on the Control pin turns the output pin on. The Fault pin reports short circuit, open circuit, and overtemperature conditions on the IC. If a fault is present, the open collector output Fault pin will be low. Typical numbers for faults are: exceeding 500 mA of drive current will report a short circuit. Less than 40 mA (typical) will report an open circuit. A temperature fault will be reported when the die temperature exceeds 180°C (typical). Faults are only reported when the Control pin is high, due to the low quiescent current when the Control pin is low and the output device is turned off. The CS1108 is designed to provide overcurrent protection by duty cycle control. When the lamp current exceeds the internally programmed current limit threshold (typically 500 mA), the output enters duty cycle mode to reduce power dissipation of the IC to a safe level. Output CS1108 10 nF VCC GND Fault GND Control GND 20 k VBAT GND VCC microprocessor Figure 2. Applications Diagram http://onsemi.com 3 CS1108 PACKAGE DIMENSIONS SO–8 DF SUFFIX CASE 751–07 ISSUE V –X– A 8 5 0.25 (0.010) S B 1 M Y M 4 K –Y– G C N DIM A B C D G H J K M N S X 45 SEATING PLANE –Z– 0.10 (0.004) H M D 0.25 (0.010) M Z Y S X J S MILLIMETERS MIN MAX 4.80 5.00 3.80 4.00 1.35 1.75 0.33 0.51 1.27 BSC 0.10 0.25 0.19 0.25 0.40 1.27 0 8 0.25 0.50 5.80 6.20 INCHES MIN MAX 0.189 0.197 0.150 0.157 0.053 0.069 0.013 0.020 0.050 BSC 0.004 0.010 0.007 0.010 0.016 0.050 0 8 0.010 0.020 0.228 0.244 PACKAGE THERMAL DATA SO–8 Unit RΘJC Typical 25 °C/W RΘJA Typical 110 °C/W Parameter ON Semiconductor and are trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. PUBLICATION ORDERING INFORMATION Literature Fulfillment: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303–675–2175 or 800–344–3860 Toll Free USA/Canada Fax: 303–675–2176 or 800–344–3867 Toll Free USA/Canada Email: [email protected] JAPAN: ON Semiconductor, Japan Customer Focus Center 4–32–1 Nishi–Gotanda, Shinagawa–ku, Tokyo, Japan 141–0031 Phone: 81–3–5740–2700 Email: [email protected] ON Semiconductor Website: http://onsemi.com For additional information, please contact your local Sales Representative. N. American Technical Support: 800–282–9855 Toll Free USA/Canada http://onsemi.com 4 CS1108/D