LM285-2 LM385-2 LM385B-2 SLVS023F LM385 LM385D-2 LM385LP-2 LM385PW-2 LM385BD-2

MICROPOWER VOLTAGE REFERENCES SLVS023F JANUARY 1989 REVISED JANUARY 2002 D D D D D D Operating Current Range . . . 20

LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 D D D D D D Operating Current Range . . . 20 µA to 20 mA 1.5% and 3% Initial Voltage Tolerance Reference Impedance LM385 LM385 . . . 1 Max at 25°C All Devices . . . 1.5 Max Over Full Temperature Range Very Low Power Consumption Applications: Portable Meter References Portable Test Instruments Battery-Operated Systems Current-Loop Instrumentation Panel Meters Designed to be Interchangeable With National LM285-2 LM285-2.5 and LM385-2 LM385-2.5 D OR PW PACKAGE (TOP VIEW) NC NC NC ANODE 1 8 2 7 3 6 4 5 CATHODE NC NC NC NC No internal connection LP PACKAGE (TOP VIEW) ANODE CATHODE NC NC No internal connection description These micropower two-terminal band-gap voltage references operate over a 20-µA to 20-mA current range and feature exceptionally low dynamic impedance and good temperature stability. On-chip trimming provides tight voltage tolerance. The band-gap reference for these devices has low noise and long-term stability. The design makes these devices exceptionally tolerant of capacitive loading and, thus, easier to use in most reference applications. The wide dynamic operating temperature range accommodates varying current supplies, with excellent regulation. The extremely low power drain of this series makes them useful for micropower circuitry. These voltage references can be used to make portable meters, regulators, or general-purpose analog circuitry, with battery life approaching shelf life. The wide operating current range allows them to replace older references with tighter-tolerance parts. The LM285-2 LM285-2.5 is characterized for operation from 40°C to 85°C. The LM385-2 LM385-2.5 and LM385B-2 LM385B-2.5 are characterized for operation from 0°C to 70°C. AVAILABLE OPTIONS PACKAGED DEVICES TA 0°C to 70°C 40°C to 85°C VZ TOLERANCE 3% SMALL OUTLINE (D) PLASTIC THIN SHRINK SMALL OUTLINE (PW) PLASTIC (LP) LM385D-2 LM385D-2.5 LM385LP-2 LM385LP-2.5 LM385PW-2 LM385PW-2.5 1.5% LM385BD-2 LM385BD-2.5 LM385BLP-2 LM385BLP-2.5 LM385BPW-2 LM385BPW-2.5 1.5% LM285D-2 LM285D-2.5 LM285LP-2 LM285LP-2.5 - The D and LP packages are also available taped and reeled. Add the suffix R to the device type (e.g., LM385DR-2-5 LM385DR-2-5). The PW package is only available taped and reeled. For ordering purposes, the decimal point in the part number must be replaced with a hyphen (i.e., show the -2.5 suffix as "-2-5"). Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. Copyright 2002, Texas Instruments Incorporated PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 1 LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 symbol ANODE CATHODE schematic CATHODE Q13 600 k 7.5 k Q12 Q4 Q7 200 k Q11 Q3 50 k Q10 Q1 20 pF 300 k 20 pF 500 Q9 Q2 Q5 Q6 100 k 500 Q8 Q14 500 60 k ANODE NOTE A: All component values shown are nominal. absolute maximum ratings over operating free-air temperature range Reverse current, IR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 mA Forward current, IF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 mA Package thermal impedance, JA (see Notes 1 and 2): D package . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97°C/W LP package . . . . . . . . . . . . . . . . . . . . . . . . . . 156°C/W PW package . . . . . . . . . . . . . . . . . . . . . . . . . 149°C/W Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C to 150°C Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. Maximum power dissipation is a function of TJ(max), JA, and TA. The maximum allowable power dissipation at any allowable ambient temperature is PD = (TJ(max) TA)/JA. Operation at the absolute maximum TJ of 150°C can affect reliability. 2. The package thermal impedance is calculated in accordance with JESD 51-7. recommended operating conditions MIN IZ TA 2 Operating free-air temperature range free air LM285-2 LM285-2.5 LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 MAX 0.02 Reference current 20 40 85 0 70 UNIT mA °C LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 electrical characteristics at specified free-air temperature PARAMETER LM285-2 LM285-2.5 LM385-2 LM385-2.5 LM385B-2 LM385B-2.5 TEST CONDITIONS TA MIN TYP MAX MIN TYP MAX MIN TYP MAX 2.462 2.5 2.538 2.425 2.5 2.575 2.462 2.5 2.538 VZ Reference voltage IZ = 20 µA to 20 mA 25°C VZ Average temperature coefficient of reference voltage IZ = 20 µA to 20 mA 25°C VZ Change in reference voltage with current t IZ = 20 µ µA to 1 mA IZ = 1 µ µA to 20 mA VZ/t Long-term change in reference voltage IZ(min) Minimum reference current zz Reference impedance IZ = 100 µA Vn Broadband noise voltage IZ = 100 µA, f = 10 Hz to 10 kHz IZ = 100 µA ±20 25°C ±20 1 ±20 2 UNIT V ppm/°C 2 Full range 1.5 2 2 25°C 10 20 20 Full range 30 30 30 25°C Full range 25°C ±20 8 20 8 0.2 0.6 0.4 Full range 25°C ±20 1.5 120 ±20 20 8 1 0.4 1.5 120 ppm/khr 20 1 1.5 120 mV µA µV Full range is 0°C to 70°C for the LM385-2 LM385-2.5 and LM385B-2 LM385B-2.5, and 40°C to 85°C for the LM285-2 LM285-2.5. The average temperature coefficient of reference voltage is defined as the total change in reference voltage divided by the specified temperature range. POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 3 LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 TYPICAL CHARACTERISTICS REVERSE CURRENT vs REVERSE VOLTAGE REFERENCE VOLTAGE CHANGE vs REVERSE CURRENT 100 16 TA = 55°C to 125°C V Z Reference Voltage Change mV I R Reverse Current µ A TA = 55°C to 125°C 10 1 0.1 0 0.5 1 2.5 2 1.5 12 8 4 0 4 0.01 3 VR Reverse Voltage V 0.1 1 Figure 1 100 Figure 2 FORWARD VOLTAGE vs FORWARD CURRENT REFERENCE VOLTAGE vs FREE-AIR TEMPERATURE 2.525 1.6 IZ = 20 µA to 20 mA TA = 25°C 2.52 1.2 2.515 VZ Reference Voltage V 1.4 V F Forward Voltage V 10 IR Reverse Current mA 1 0.8 0.6 0.4 2.505 2.5 2.495 2.49 0.2 0 0.01 2.51 2.485 0.1 1 10 100 2.48 55 35 15 5 25 45 65 85 105 125 TA Free-Air Temperature °C IF Forward Current mA Figure 3 Figure 4 Data at high and low temperatures are applicable only within the rated operating free-air temperature ranges of the various devices. 4 POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 TYPICAL CHARACTERISTICS REFERENCE IMPEDANCE vs FREQUENCY REFERENCE IMPEDANCE vs REFERENCE CURRENT 1000 10 k IZ = 100 µA TA = 25°C z z Reference Impedance z z Reference Impedance f = 25 Hz TA = MIN to MAX 100 10 1 0.1 0.01 0.1 1 10 1k 100 10 1 0.1 0.01 100 0.1 1 Iz Reference Current mA NOISE VOLTAGE vs FREQUENCY TA = 25°C 100 µA Filtered RMS Output Noise Voltage µV Vn Noise Voltage nV/ Hz 120 IZ = 100 µA TA = 25°C 1000 800 600 400 200 100 1000 FILTERED RMS OUTPUT NOISE VOLTAGE vs FREQUENCY 1400 0 10 100 Figure 6 Figure 5 1200 10 f Frequency kHz 1k 10 k 100 k 100 RC Low Pass R C 80 60 40 20 0 0.1 f Frequency Hz 1 10 100 f Frequency kHz Figure 7 Figure 8 Data at high and low temperatures are applicable only within the rated operating free-air temperature ranges of the various devices. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions. POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 5 LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 TYPICAL CHARACTERISTICS TRANSIENT RESPONSE 3 ÎÎÎ ÎÎÎ Output 24 k 2 VI 1 VO 0 5 ÎÎ ÎÎ Input and Output Voltage V 4 Input 0 0 100 t Time µs 500 600 Figure 9 Data at high and low temperatures are applicable only within the rated operating free-air temperature ranges of the various devices. 6 POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 LM285-2 LM285-2.5, LM385-2 LM385-2.5, LM385B-2 LM385B-2.5 MICROPOWER VOLTAGE REFERENCES SLVS023F SLVS023F JANUARY 1989 REVISED JANUARY 2002 APPLICATION INFORMATION IO 60 µA + Two Mercury Cells 2.6 V V+ 3.3 k 200 k ±1% LM334 LM334 cw 2.00 k ±1% cw V 20 k 500 412 ±1% 953 ±1% LM385-2 LM385-2.5 R + Type K Meter Adjust for 12.17 mV at 25°C across 412 Figure 10. Thermocouple Cold-Junction Compensator 3.7 V V+ 30 V V+ LM334 LM334 R V 2.74 k 2.5 V LM385-2 LM385-2.5 Figure 11. Operation Over a Wide Supply Range 9V 221 k LM385-2 LM385-2.5 Figure 12. Reference From a 9-V Battery POST OFFICE BOX 655303 · DALLAS, TEXAS 75265 7 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI's terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI's standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using TI components. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information published by TI regarding thirdparty products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for such altered documentation. Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Mailing Address: Texas Instruments Post Office Box 655303 Dallas, Texas 75265 Copyright 2001, Texas Instruments Incorporated