LM134H

LM134 NSC | Alldatasheet

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n 0.02%/V current regulation n Programmable from 1µA to 10mA n True 2-terminal operation n Available as fully specified temperature sensor n ±3% initial accuracy Connection Diagrams SO-8 Surface Mount Package DS005697-24 Order Number LM334M or LM334MX See NS Package Number M08A SO-8 Alternative Pinout Surface Mount Package DS005697-25 Order Number LM334SM or LM334SMX See NS Package Number M08A TO-46 Metal Can Package DS005697-12 V− Pin is electrically connected to case. Bottom View Order Number LM134H, LM234H or LM334H See NS Package Number H03H TO-92 Plastic Package DS005697-10 Bottom View Order Number LM334Z, LM234Z-3 or LM234Z-6 See NS Package Number Z03A March 2000 LM134/LM234/LM334 3-Terminal Adjustable Current Sources © 2000 National Semiconductor Corporation DS005697 www.national.com

Absolute Maximum Ratings(Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. V + to V− Forward Voltage LM134/LM234/LM334 40V LM234-3/LM234-6 30V V + to V− Reverse Voltage 20V R Pin to V− Voltage 5V Set Current 10 mA Power Dissipation 400 mW ESD Susceptibility (Note 6) 2000V Operating Temperature Range (Note 5) LM134 −55˚C to +125˚C LM234/LM234-3/LM234-6 −25˚C to +100˚C LM334 0˚C to +70˚C Soldering Information Vapor Phase (60 sec.) 215˚C Infrared (15 sec.) 220˚C See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” (Appendix D) for other methods of sol- dering surface mount devices. Electrical Characteristics(Note 2) Parameter Conditions LM134/LM234 LM334 Units Min Typ Max Min Typ Max Set Current Error, V+=2.5V, 10µA ≤ ISET ≤ 1mA 3 6 % (Note 3) 1mA < ISET ≤ 5mA 5 8 % 2µA ≤ ISET < 10µA 8 12 % Ratio of Set Current to 100µA ≤ ISET ≤ 1mA 14 18 23 14 18 26 Bias Current 1mA ≤ ISET ≤ 5mA 14 14 2µ A≤ISET ≤100 µA 18 23 18 26 Minimum Operating Voltage 2µA ≤ ISET ≤ 100µA 0.8 0.8 V 100µA < ISET ≤ 1mA 0.9 0.9 V 1mA < ISET ≤ 5mA 1.0 1.0 V Average Change in Set Current 2µA ≤ ISET ≤ 1mA 5V ≤ V+ ≤ 40V 0.01 0.03 0.01 0.05 %/V 1mA < ISET ≤ 5mA 5V ≤ V ≤ 40V 0.02 0.02 %/V Temperature Dependence of 25µA ≤ ISET ≤ 1mA 0.96T T 1.04T 0.96T T 1.04T Set Current (Note 4) Effective Shunt Capacitance 15 15 pF Note 1:.“Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the deviceis functional, but do not guarantee specific performance limits. Note 2:Unless otherwise specified, tests are performed at Tj= 25˚C with pulse testing so that junction temperature does not change during test Note 3:Set current is the current flowing into the V+ pin. For the Basic 2-Terminal Current Source circuit shown on the first page of this data sheet. ISET is determined by the following formula: ISET = 67.7 mV/RSET (@ 25˚C). Set current error is expressed as a percent deviation from this amount. ISET increases at 0.336%/˚C@ Tj Note 4:ISET is directly proportional to absolute temperature (˚K). ISET at any temperature can be calculated from: ISET =Io (T/To) where Io is ISET measured at To (˚K). Note 5:For elevated temperature operation, TJ max is: LM134 150˚C LM234 125˚C LM334 100˚C Thermal Resistance TO-92 TO-46 SO-8 θja(Junction to Ambient) 180˚C/W (0.4" leads) 440˚C/W 165˚C/W 160˚C/W (0.125" leads) θjc(Junction to Case) N/A 32˚C/W 80˚C/W Note 6:Human body model, 100pF discharged through a 1.5kΩ resistor. LM134/LM234/LM334 www.national.com 2

Electrical Characteristics(Note 2) Parameter Conditions LM234-3 LM234-6 Units Min Typ Max Min Typ Max Set Current Error, V+=2.5V, 100µA ≤ ISET ≤ 1mA ±1 ±2% (Note 3) T J = 25˚ Equivalent Temperature Error ±3 ±6˚ C Ratio of Set Current to 100µA ≤ ISET ≤ 1mA 14 18 26 14 18 26 Bias Current Minimum Operating Voltage 100µA I SET ≤ 1mA 0.9 0.9 V Average Change in Set Current 100µA ≤ ISET ≤ 1mA 5V ≤ V+ ≤ 30V 0.01 0.03 0.01 0.05 %/V Temperature Dependence of 100µA ≤ ISET ≤ 1mA 0.98T T 1.02T 0.97T T 1.03T Set Current (Note 4) and Equivalent Slope Error ±2 ±3% Effective Shunt Capacitance 15 15 pF LM134/LM234/LM334 www.national.com3

Typical Performance Characteristics Output Impedance DS005697-30 Maximum Slew Rate Linear Operation DS005697-31 Start-Up DS005697-32 Transient Response DS005697-33 Voltage Across RSET (VR ) DS005697-34 Current Noise DS005697-35 LM134/LM234/LM334 www.national.com 4

bias current (IBIAS), as shown inFigure 1. LM134, or cause large currents to flow. current due to temperature rise will be (0.4) (0.33) = 0.132%. leads can reduce this effect by more than 3:1. FIGURE 1. Basic Current Source

Application Hints(Continued) This circuit will eliminate most of the LM134’s temperature coefficient, and it does a good job even if the estimates of the diode’s characteristics are not accurate (as the following ex- ample will show). For lowest tempco with a specific diode at the desired I SET , however, the circuit should be built and tested over temperature. If the measured tempco of ISET is positive, R2 should be reduced. If the resulting tempco is negative, R2 should be increased. The recommended diode for use in this circuit is the 1N457 because its tempco is cen- tered at 11 times the tempco of the LM134, allowing R 2 =1 0 R 1. You can also use this circuit to create a current source with non-zero tempcos by setting the tempco component of the tempco equation to the desired value instead of 0. EXAMPLE: A 1mA, Zero-Tempco Current Source First, solve for R 1 and R2: The values of R1 and R2 can be changed to standard 1% re- sistor values (R1 = 133Ω and R2 = 1.33kΩ ) with less than a 0.75% error. If the forward voltage drop of the diode was 0.65V instead of the estimate of 0.6V (an error of 8%), the actual set current will be an error of less than 5%. If the estimate for the tempco of the diode’s forward voltage drop was off, the tempco cancellation is still reasonably ef- fective. Assume the tempco of the diode is 2.6mV/˚C instead of 2.5mV/˚C (an error of 4%). The tempco of the circuit is now: A 1mA LM134 current source with no temperature compen- sation would have a set resistor of 68Ω and a resulting tempco of So even if the diode’s tempco varies as much as±4% from its estimated value, the circuit still eliminates 98% of the LM134’s inherent tempco. Typical Applications Ground Referred Fahrenheit Thermometer DS005697-15 *Select R3 = VREF /583µA. VREF may be any stable positive voltage≥ 2V Trim R3 to calibrate LM134/LM234/LM334 www.national.com7

Typical Applications(Continued) Terminating Remote Sensor for Voltage Output DS005697-14 Low Output Impedance Thermometer DS005697-6 *Output impedance of the LM134 at the “R” pin is approximately where R2 is the equivalent external resistance connected from the V− pin to ground. This negative resistance can be reduced by a factor of 5 or more by inserting an equivalent resistor R 3 =( R2/16) in series with the output. Low Output Impedance Thermometer DS005697-16 Higher Output Current DS005697-5 *Select R1 and C1 for optimum stability Basic 2-Terminal Current Source DS005697-1 LM134/LM234/LM334 www.national.com 8

Typical Applications(Continued) Micropower Bias DS005697-17 Low Input Voltage Reference Driver DS005697-18 Ramp Generator DS005697-19 LM134/LM234/LM334 www.national.com9

Typical Applications(Continued) 1.2V Reference Operates on 10 µA and 2V DS005697-20 *Select ratio of R1 to R2 to obtain zero temperature drift 1.2V Regulator with 1.8V Minimum Input DS005697-7 *Select ratio of R1 to R2 for zero temperature drift Zener Biasing DS005697-49 Alternate Trimming Technique DS005697-50 *For±10% adjustment, select RSET 10% high, and make R1≈ 3R SET Buffer for Photoconductive Cell DS005697-51 FET Cascoding for Low Capacitance and/or Ultra High Output Impedance DS005697-21 *Select Q1 or Q2 to ensure at least 1V across the LM134. Vp (1 − ISET /IDSS )≥ 1.2V. DS005697-22 LM134/LM234/LM334 www.national.com 10

Typical Applications(Continued) Schematic Diagram Generating Negative Output Impedance DS005697-23 *ZOUT ≈ −16 • R1 (R1/VIN must not exceed ISET ) In-Line Current Limiter DS005697-9 *Use minimum value required to ensure stability of protected device. This minimizes inrush current to a direct short. DS005697-11 LM134/LM234/LM334 www.national.com11

Physical Dimensionsinches (millimeters) unless otherwise noted Order Number LM134H, LM234H or LM334H LM134/LM234/LM334 www.national.com 12

Physical Dimensionsinches (millimeters) unless otherwise noted (Continued) Order Number LM334M, LM334MX, LM334SM or LM334SMX Order Number LM334Z, LM234Z-3 or LM234Z-6 LM134/LM234/LM334 www.national.com13

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. 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 Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com National Semiconductor Europe Fax: +49 (0) 180-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 National Semiconductor Asia Pacific Customer Response Group Tel: 65-2544466 Fax: 65-2504466 Email: ap.support@nsc.com National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 www.national.com LM134/LM234/LM334 3-Terminal Adjustable Current Sources 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.