LM185/LM285/LM385 Adjustable Micropower Voltage References General Description The LM185/LM285/LM385 are micropower 3-terminal adjustable band-gap voltage reference diodes. Operating from 1.24 to 5.3V and over a 10µA to 20mA current range, they feature exceptionally low dynamic impedance and good temperature stability. On-chip trimming is used to provide tight voltage tolerance. Since the LM185 band-gap reference uses only transistors and resistors, low noise and good long-term stability result. Careful design of the LM185 has made the device tolerant of capacitive loading, making it easy to use in almost any reference application. The wide dynamic operating range allows its use with widely varying supplies with excellent regulation. The extremely low power drain of the LM185 makes it useful for micropower circuitry. This voltage reference can be used to make portable meters, regulators or general purpose analog circuitry with battery life approaching shelf life. Further, the wide operating current allows it to replace older references with a tighter tolerance part. Connection Diagrams The LM185 is rated for operation over a −55˚C to 125˚C temperature range, while the LM285 is rated −40˚C to 85˚C and the LM385 0˚C to 70˚C. The LM185 is available in a hermetic TO-46 package and a leadless chip carrier package, while the LM285/LM385 are available in a low-cost TO-92 molded package, as well as S.O. Features n n n n n Adjustable from 1.24V to 5.30V Operating current of 10µA to 20mA 1% and 2% initial tolerance 1Ω dynamic impedance Low temperature coefficient SOIC Package TO-92 Plastic Package DS005250-9 Bottom View TO-46 Metal Can Package DS005250-10 Top View 20-Leadless Chip Carrier DS005250-1 Bottom View DS005250-15 Top View © 2000 National Semiconductor Corporation DS005250 www.national.com LM185/LM285/LM385 Adjustable Micropower Voltage Reference February 2000 LM185/LM285/LM385 Ordering Information Package Temperature Range −55˚C to 125˚C −40˚C to 85˚C 0˚C to 70˚C NSC Drawing LM185BH LM185BH/883 TO-46 H03H LM185BYH LM185BYH/883 TO-92 LM285BXZ LM385BXZ LM285BYZ LM385BYZ LM285Z LM385BZ LM285M LM385M LM285BYM LM385BM Z03A LM385Z 8-Pin SOIC 20-Leadless Chip Carrier LM185BE/883 E20A Block Diagram DS005250-13 Typical Applications 1.2V Reference 5.0V Reference DS005250-14 DS005250-2 www.national.com M08A 2 Storage Temperature −55˚C to 150˚C Soldering Information TO-92 Package (10 sec.) 260˚C TO-46 Package (10 sec.) 300˚C SO Package Vapor Phase (60 sec.) 215˚C Infrared (15 sec.) 220˚C See An-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of soldering surface mount devices. If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. (Note 2) Reverse Current Forward Current Operating Temperature Range (Note 3) LM185 Series LM285 Series LM385 Series 30mA 10mA −55˚C to 125˚C −40˚C to 85˚C 0˚C to 70˚C Electrical Characteristics (Note 4) LM185, LM285 LM385 LM185BX, LM185BY Parameter LM185B, LM285BX, Conditions Typ IR = 100µA Reference Voltage LM385BX, 1.240 LM285 LM385 LM385BY Units Typ LM285BY (Limit) Tested Design Tested Design Tested Design Tested Limit Limit Limit Limit Limit Limit Limit Limit (Note 5) (Note 6) (Note 5) (Note 6) (Note 5) (Note 6) (Note 5) (Note 6) 1.265 1.270 1.252 1.255 1.265 1.270 1.252 1.240 Design 1.255 1.228 1.215 1.205 1.228 1.215 1.215 1.205 1.215 V (min) Reference Voltage IMIN < IR < 1mA Change with Current 1mA < IR < 20mA Dynamic Output IR = 100µA, f = 100Hz Impedance IAC = 0.1 IR VOUT = VREF 0.3 0.4 VOUT = 5.3V 0.7 1 Reference Voltage V (max) 0.2 1 1.5 1 1.5 0.2 1 1.5 1 1.5 mV 4 10 20 10 20 5 15 25 15 25 (max) Ω IR = 100µA mV Change with Output 1 3 6 3 6 2 5 10 5 10 (max) 13 20 25 20 25 16 30 35 30 35 nA (max) Voltage Feedback Current Minimum Operating VOUT = VREF 6 9 10 9 10 7 11 13 11 13 µA Current (see curve) VOUT = 5.3V 30 45 50 45 50 35 55 60 55 60 (max) Output Wideband IR = 100µA, 10Hz < f < 10kHz Noise VOUT = VREF 50 50 VOUT = 5.3V 170 170 Average Temperature IR = 100µA Coefficient (Note 7) X Suffix 30 Y Suffix 50 All Others Long Term Stability 30 ppm/˚c 50 150 IR = 100µA, T = 1000 Hr, µVrms 150 20 (max) 150 20 150 ppm TA = 25˚C ± 0.1˚C Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Note 2: Refer to RETS185H for military specifications. Note 3: For elevated temperature operation, TJmax is: LM185 150˚C LM285 125˚C LM385 100˚C Thermal Resistance θJA (Junction to Ambient) TO-92 TO-46 SO-8 180˚C/W (0.4" leads) 440˚C/W 165˚C/W 80˚C/W N/A 170˚C/W (0.125" leads) θJC (Junction to Case) N/A 3 www.national.com LM185/LM285/LM385 Absolute Maximum Ratings (Note 1) LM185/LM285/LM385 Electrical Characteristics (Note 4) (Continued) Note 4: Parameters identified with boldface type apply at temperature extremes. All other numbers apply at TA = TJ = 25˚C. Unless otherwise specified, all parameters apply for VREF < VOUT < 5.3V. Note 5: Guaranteed and 100% production tested. Note 6: Guaranteed, but not 100% production tested. These limits are not to be used to calculate average outgoing quality levels. Note 7: The average temperature coefficient is defined as the maximum deviation of reference voltage at all measured temperatures from TMIN to TMAX, divided by TMAX − TMIN. The measured temperatures are −55, −40, 0, 25, 70, 85, 125˚C. Typical Performance Characteristics Temperature Drift of 3 Representative Units Feedback Current Minimum Operating Current DS005250-17 DS005250-18 DS005250-16 Reverse Characteristics Reverse Characteristics DS005250-19 Output Noise Voltage DS005250-20 Dynamic Output Impedance DS005250-23 DS005250-22 www.national.com Forward Characteristics 4 DS005250-21 Response Time DS005250-24 Temperature Coefficient Typical LM185 LM185/LM285/LM385 Typical Performance Characteristics (Continued) LM285 LM385 DS005250-4 Typical Applications Precision 10V Reference Low AC Noise Reference DS005250-25 DS005250-26 25V Low Current Shunt Regulator 200 mA Shunt Regulator DS005250-27 DS005250-28 5 www.national.com LM185/LM285/LM385 Typical Applications (Continued) Series-Shunt 20 mA Regulator High Efficiency Low Power Regulator DS005250-29 DS005250-30 Voltage Level Detector Voltage Level Detector DS005250-31 DS005250-32 Fast Positive Clamp 2.4V + ∆VD1 Bidirectional Clamp ± 2.4V DS005250-34 DS005250-33 www.national.com 6 LM185/LM285/LM385 Typical Applications (Continued) Bidirectional Adjustable Clamp ± 1.8V to ± 2.4V Bidirectional Adjustable Clamp ± 2.4V to ± 6V DS005250-36 DS005250-35 Simple Floating Current Detector Current Source DS005250-38 DS005250-37 7 www.national.com LM185/LM285/LM385 Typical Applications (Continued) Precision Floating Current Detector DS005250-39 *D1 can be any LED, VF =1.5V to 2.2V at 3 mA. D1 may act as an indicator. D1 will be on if ITHRESHOLD falls below the threshold current, except with I=O. Centigrade Thermometer, 10mV/˚C Freezer Alarm DS005250-11 DS005250-12 www.national.com 8 LM185/LM285/LM385 Schematic Diagram DS005250-8 9 www.national.com LM185/LM285/LM385 Physical Dimensions inches (millimeters) unless otherwise noted 20-Leadless Chip Carrier (E) NS Package Number E20A TO-46 Metal Can Package (H) NS Package Number H03H www.national.com 10 LM185/LM285/LM385 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) SO Package (M) NS Package Number M08A TO-92 Plastic Package (Z) NS Package Number Z03A 11 www.national.com LM185/LM285/LM385 Adjustable Micropower Voltage Reference Notes 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 AND GENERAL COUNSEL 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 Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: [email protected] www.national.com National Semiconductor Europe Fax: +49 (0) 180-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 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. 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