DS8973 9-Digit LED Driver General Description The DS8973 is a 9-digit driver designed to operate from 3-cell battery supplies. Each driver will sink 100 mA to less than 0.7V when driven by only 0.1 mA. Each input is blocked by diodes so that the input can be driven below ground with virtually no current drain. This is especially important in calculator systems employing a DC-to-DC converter on the negative side of the battery. If the converter were on the positive side of the battery, the converter would have to handle all of the display current, as well as the MOS calculator chip current. But if it is on the negative side, it only has to handle the MOS current. The DS8973 is designed for the more efficient operating mode. Features Y Y Y Y Nine complete digit drivers Built-in low battery indicator High current outputsÐ100 mA Straight through pin out for easy board layout Equivalent Circuit Diagrams Typical Driver Circuit Typical D.P. Out Circuit TL/F/5851 – 2 TL/F/5851 – 1 Connection Diagram Dual-In-Line Package TL/F/5851 – 3 Top View Order Number DS8973N See NS Package Number N22A C1995 National Semiconductor Corporation TL/F/5851 RRD-B30M105/Printed in U. S. A. DS8973 9-Digit LED Driver May 1986 Absolute Maximum Ratings (Note 1) Operating Conditions If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. Min Max Supply Voltage (VB) 3.0 5.5 V Supply Voltage (VCC1) Temperature (TA) 3.0 0 9.5 a 70 V §C Supply Voltage Input Voltage Output Voltage Storage Temperature Range 10V 10V 10V Units b 65§ C to a 150§ C Maximum Power Dissipation* at 25§ C Molded Package Lead Temperature (Soldering, 4 seconds) 1673 mW 260§ C *Derate molded package 13.39 mW/§ C above 25§ C. Electrical Characteristics Symbol VIH Parameter Conditions Min Typ Max Units Logical ‘‘1’’ Input Voltage VCC e Max 3.9 IIH Logical ‘‘1’’ Input Current VCC e Max, VIH e 3.9V V 0.1 VIL Logical ‘‘0’’ Input Voltage VCC e Max 0.5 V IIL Logical ‘‘0’’ Input Current VCC e Max, VIL e 0.5V 40 mA VBH High Battery Threshold VOT (Pin 1) e 1V, IOT s b50 mA, TA e 25§ C, VIH (Pin 2) e 3.9V DS8973 VBL Low Battery Threshold VOT (Pin 1) e 2.1V, IOT s b6 mA, TA e 25§ C, VIH (Pin 2) e 3.9V DS8973 ICEX Logical ‘‘1’’ Output Current VOL ICC1 IB 0.3 3.6 mA V 3.2 V VCC e Min, VOH e 9.5V, VIL e 0.5V 50 mA Logical ‘‘0’’ Output Voltage VCC e Min, IOL e 100 mA, VIH e 3.9V 0.7 V Supply Current VCC e Max, One Input ‘‘ON’’ 6 mA Pin 21 (High Battery Supply) VCC e Max, VB e Max 1.2 mA Note 1: ‘‘Absolute Maximum Ratings’’ are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the devices should be operated at these limits. The table of ‘‘Electrical Characteristics’’ provides conditions for actual device operation. Note 2: Unless otherwise specified, min/max limits apply across the 0§ C to a 70§ C range. All typicals are given for TA e 25§ C. Note 3: All currents into device pins shown as positive, out of device pins as negative, all voltages referenced to ground unless otherwise noted. All values shown as max or min on absolute value basis. 2 3 DS8973 9-Digit LED Driver Physical Dimensions inches (millimeters) Molded Dual-In-Line Package (N) Order Number DS8973N NS Package Number N22A LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. National Semiconductor Corporation 1111 West Bardin Road Arlington, TX 76017 Tel: 1(800) 272-9959 Fax: 1(800) 737-7018 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Europe Fax: (a49) 0-180-530 85 86 Email: cnjwge @ tevm2.nsc.com Deutsch Tel: (a49) 0-180-530 85 85 English Tel: (a49) 0-180-532 78 32 Fran3ais Tel: (a49) 0-180-532 93 58 Italiano Tel: (a49) 0-180-534 16 80 National Semiconductor Hong Kong Ltd. 13th Floor, Straight Block, Ocean Centre, 5 Canton Rd. Tsimshatsui, Kowloon Hong Kong Tel: (852) 2737-1600 Fax: (852) 2736-9960 National Semiconductor Japan Ltd. Tel: 81-043-299-2309 Fax: 81-043-299-2408 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.