LM4050AEM3-8.2

LM4050 Precision Micropower Shunt Voltage Reference July 2004 LM4050 Precision Micropower Shunt Voltage Reference General Description Ideal for space critical applications, the LM4050 precision voltage reference is available in the sub-miniature (3 mm x 1.3 mm) SOT-23 surface-mount package. The LM4050’s design eliminates the need for an external stabilizing capacitor while ensuring stability with any capacitive load, thus making the LM4050 easy to use. Further reducing design effort is the availability of several fixed reverse breakdown voltages: 2.048V, 2.500V, 4.096V, 5.000V, 8.192V, and 10.000V. The minimum operating current increases from 60 µA for the LM4050-2.0 to 100 µA for the LM4050-10.0. All versions have a maximum operating current of 15 mA. The LM4050 utilizes fuse and zener-zap reverse breakdown voltage trim during wafer sort to ensure that the prime parts have an accuracy of better than ± 0.1% (A grade) at 25˚C. Bandgap reference temperature drift curvature correction and low dynamic impedance ensure stable reverse breakdown voltage accuracy over a wide range of operating temperatures and currents. All grades and voltage options of the LM4050 are available in both an industrial temperature range (−40˚C and +85˚C) and an extended temperature range (−40˚C and +125˚C). n Tolerates capacitive loads n Fixed reverse breakdown voltages of 2.048V, 2.500V, 4.096V, 5.000V, 8.192V, and 10.000V Key Specifications (LM4050-2.5) j Output voltage tolerance (A grade, 25˚C) j Low output noise ± 0.1% (max) 41 µVrms(typ) 60 µA to 15 mA −40˚C to +85˚C −40˚C to +125˚C 50 ppm/˚C (max) (10 Hz to 10 kHz) j Wide operating current range j Industrial temperature range j Extended temperature range j Low temperature coefficient Applications n n n n n n n n Portable, Battery-Powered Equipment Data Acquisition Systems Instrumentation Process Control Energy Management Product Testing Automotive Precision Audio Components Features n Small packages: SOT-23 n No output capacitor required Connection Diagram SOT-23 10104501 *This pin must be left floating or connected to pin 2. Top View See NS Package Number MF03A © 2004 National Semiconductor Corporation DS101045 www.national.com LM4050 Ordering Information Industrial Temperature Range (−40˚C to +85˚C) Reverse Breakdown Voltage Tolerance at 25˚C and Average Reverse Breakdown Voltage Temperature Coefficient LM4050 Supplied as 1000 Units, Tape and Reel LM4050AIM3-2.0 LM4050AIM3-2.5 LM4050AIM3-4.1 LM4050 Supplied as 3000 Units, Tape and Reel LM4050AIM3X-2.0 LM4050AIM3X-2.5 LM4050AIM3X-4.1 LM4050AIM3X-5.0 LM4050AIM3X-8.2 LM4050AIM3X-10 LM4050BIM3X-2.0 LM4050BIM3X-2.5 LM4050BIM3X-4.1 LM4050BIM3X-5.0 LM4050BIM3X-8.2 LM4050BIM3X-10 LM4050CIM3X-2.0 LM4050CIM3X-2.5 LM4050CIM3X-4.1 LM4050CIM3X-5.0 LM4050CIM3X-8.2 LM4050CIM3X-10 ± 0.1%, 50 ppm/˚C max (A grade) LM4050AIM3-5.0 LM4050AIM3-8.2 LM4050AIM3-10 LM4050BIM3-2.0 LM4050BIM3-2.5 LM4050BIM3-4.1 ± 0.2%, 50 ppm/˚C max (B grade) LM4050BIM3-5.0 LM4050BIM3-8.2 LM4050BIM3-10 LM4050CIM3-2.0 LM4050CIM3-2.5 LM4050CIM3-4.1 ± 0.5%, 50 ppm/˚C max (C grade) LM4050CIM3-5.0 LM4050CIM3-8.2 LM4050CIM3-10 Extended Temperature Range (−40˚C to +125˚C) Reverse Breakdown Voltage Tolerance at 25˚C and Average Reverse Breakdown Voltage Temperature Coefficient LM4050 Supplied as 1000 Units, Tape and Reel LM4050AEM3-2.0 LM4050AEM3-2.5 LM4050AEM3-4.1 LM4050 Supplied as 3000 Units, Tape and Reel LM4050AEM3X-2.0 LM4050AEM3X-2.5 LM4050AEM3X-4.1 LM4050AEM3X-5.0 LM4050AEM3X-8.2 LM4050AEM3X-10 LM4050BEM3X-2.0 LM4050BEM3X-2.5 LM4050BEM3X-4.1 LM4050BEM3X-5.0 LM4050BEM3X-8.2 LM4050BEM3X-10 LM4050CEM3X-2.0 LM4050CEM3X-2.5 LM4050CEM3X-4.1 LM4050CEM3X-5.0 LM4050CEM3X-8.2 LM4050CEM3X-10 ± 0.1%, 50 ppm/˚C max (A grade) LM4050AEM3-5.0 LM4050AEM3-8.2 LM4050AEM3-10 LM4050BEM3-2.0 LM4050BEM3-2.5 LM4050BEM3-4.1 ± 0.2%, 50 ppm/˚C max (B grade) LM4050BEM3-5.0 LM4050BEM3-8.2 LM4050BEM3-10 LM4050CEM3-2.0 LM4050CEM3-2.5 LM4050CEM3-4.1 ± 0.5%, 50 ppm/˚C max (C grade) LM4050CEM3-5.0 LM4050CEM3-8.2 LM4050CEM3-10 www.national.com 2 LM4050 SOT-23 Package Marking Information Only three fields of marking are possible on the SOT-23’s small surface. This table gives the meaning of the three fields. Part Marking RCA RDA REA RFA RGA RNA RCB RDB REB RFB RGB RNB RCC RDC REC RFC RGC RNC A–C = Initial Reverse Breakdown Voltage or Reference Voltage Tolerance A = ± 0.1%, B = ± 0.2%, C = +0.5%, Third Field: First Field: R = Reference Second Field: N = 2.048V Voltage Option C = 2.500V Voltage Option D = 4.096V Voltage Option E = 5.000V Voltage Option F = 8.192V Voltage Option G = 10.000V Voltage Option Field Definition 3 www.national.com LM4050 Absolute Maximum Ratings (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Reverse Current Forward Current Power Dissipation (TA = 25˚C) (Note 2) M3 Package Storage Temperature Lead Temperature M3 Package Vapor phase (60 seconds) Infrared (15 seconds) ESD Susceptibility Human Body Model (Note 3) Machine Model (Note 3) 2 kV 200V +215˚C +220˚C 280 mW −65˚C to +150˚C 20 mA 10 mA Operating Ratings (Note 2) Temperature Range Industrial Temperature Range Extended temperature Range Reverse Current LM4050-2.0 LM4050-2.5 LM4050-4.1 LM4050-5.0 LM4050-8.2 LM4050-10.0 60 µA to 15 mA 60 µA to 15 mA 68 µA to 15 mA 74 µA to 15 mA 91 µA to 15 mA 100 µA to 15 mA (Tmin ≤ TA ≤ Tmax) −40˚C ≤ TA ≤ +85˚C −40˚C ≤ TA ≤ +125˚C See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of soldering surface mount devices. LM4050-2.0 Electrical Characteristics Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively. Symbol VR Parameter Reverse Breakdown Voltage Reverse Breakdown Voltage Tolerance (Note 6) Conditions IR = 100 µA IR = 100 µA Industrial Temp. Range Extended Temp. Range IRMIN Minimum Operating Current 41 60 65 ∆VR/∆T Average Reverse Breakdown Voltage Temperature Coefficient (Note 6) Reverse Breakdown Voltage Change with Operating Current Change (Note 7) IR = 10 mA IR = 1 mA IR = 100 µA ∆VR/∆IR IRMIN ≤ IR ≤ 1 mA 60 65 60 65 Typical (Note 4) 2.048 LM4050AIM3 LM4050AEM3 Limits (Note 5) LM4050BIM3 LM4050BEM3 Limits (Note 5) LM4050CIM3 LM4050CEM3 Limits (Note 5) Units (Limit) V ± 2.048 ± 9.0112 ± 12.288 ± 4.096 ± 11.4688 ± 14.7456 ± 10.24 ± 14.7456 ± 17.2032 mV (max) mV (max) mV (max) µA µA (max) µA (max) ppm/˚C ppm/˚C ± 20 ± 15 ± 15 0.3 0.8 1.2 0.8 1.2 6.0 8.0 0.8 1.2 6.0 8.0 ± 50 ± 50 ± 50 ppm/˚C (max) mV mV (max) mV (max) mV mV (max) mV (max) Ω µVrms 1 mA ≤ IR ≤ 15 mA 2.3 6.0 8.0 ZR eN ∆VR Reverse Dynamic Impedance Wideband Noise Reverse Breakdown Voltage Long Term Stability Thermal Hysteresis (Note 8) IR = 1 mA, f = 120 Hz, IAC = 0.1 IR IR = 100 µA 10 Hz ≤ f ≤ 10 kHz t = 1000 hrs T = 25˚C ± 0.1˚C IR = 100 µA ∆T = −40˚C to 125˚C 0.3 34 120 0.7 ppm mV VHYST www.national.com 4 LM4050 LM4050-2.5 Electrical Characteristics Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively. Symbol VR Parameter Reverse Breakdown Voltage Reverse Breakdown Voltage Tolerance (Note 6) Conditions IR = 100 µA IR = 100 µA Industrial Temp. Range Extended Temp. Range IRMIN Minimum Operating Current 41 60 65 ∆VR/∆T Average Reverse Breakdown Voltage Temperature Coefficient (Note 6) Reverse Breakdown Voltage Change with Operating Current Change (Note 7) IR = 10 mA IR = 1 mA IR = 100 µA ∆VR/∆IR IRMIN ≤ IR ≤ 1 mA 60 65 60 65 Typical (Note 4) 2.500 LM4050AIM3 LM4050BIM3 LM4050CIM3 LM4050AEM3 LM4050BEM3 LM4050CEM3 Limits Limits Limits (Note 5) (Note 5) (Note 5) Units (Limit) V ± 2.5 ± 11 ± 15 ± 5.0 ± 14 ± 18 ± 13 ± 21 ± 25 mV (max) mV (max) mV (max) µA µA (max) µA (max) ppm/˚C ppm/˚C ± 20 ± 15 ± 15 0.3 0.8 1.2 0.8 1.2 6.0 8.0 0.8 1.2 6.0 8.0 ± 50 ± 50 ± 50 ppm/˚C (max) mV mV (max) mV (max) mV mV (max) mV (max) Ω µVrms 1 mA ≤ IR ≤ 15 mA 2.3 6.0 8.0 ZR eN ∆VR Reverse Dynamic Impedance Wideband Noise Reverse Breakdown Voltage Long Term Stability Thermal Hysteresis (Note 8) IR = 1 mA, f = 120 Hz, IAC = 0.1 IR IR = 100 µA 10 Hz ≤ f ≤ 10 kHz t = 1000 hrs T = 25˚C ± 0.1˚C IR = 100 µA ∆T = −40˚C to 125˚C 0.3 41 120 0.7 ppm mV VHYST LM4050-4.1 Electrical Characteristics Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively. Symbol VR Parameter Reverse Breakdown Voltage Reverse Breakdown Voltage Tolerance (Note 6) Conditions IR = 100 µA IR = 100 µA Industrial Temp. Range Extended Temp. Range IRMIN Minimum Operating Current Industrial Temp. Range Extended Temp. Range ∆VR/∆T Average Reverse Breakdown Voltage Temperature Coefficient (Note 6) Reverse Breakdown Voltage Change with Operating Current Change (Note 7) IR = 10 mA IR = 1 mA IR = 100 µA ∆VR/∆IR IRMIN ≤ IR ≤ 1 mA 52 68 73 78 68 73 78 68 73 78 Typical (Note 4) 4.096 LM4050AIM3 LM4050BIM3 LM4050CIM3 LM4050AEM3 LM4050BEM3 LM4050CEM3 Limits Limits Limits (Note 5) (Note 5) (Note 5) Units (Limit) V ± 4.1 ± 18 ± 25 ± 8.2 ± 22 ± 29 ± 21 ± 34 ± 41 mV (max) mV (max) mV (max) µA µA (max) µA (max) µA (max) ppm/˚C ppm/˚C ± 30 ± 20 ± 20 0.2 0.9 1.2 0.9 1.2 7.0 10.0 0.9 1.2 7.0 10.0 ± 50 ± 50 ± 50 ppm/˚C (max) mV mV (max) mV (max) mV mV (max) mV (max) 1 mA ≤ IR ≤ 15 mA 2.0 7.0 10.0 5 www.national.com LM4050 LM4050-4.1 Electrical Characteristics (Continued) Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively. Parameter Reverse Dynamic Impedance Wideband Noise Reverse Breakdown Voltage Long Term Stability Thermal Hysteresis (Note 8) Conditions IR = 1 mA, f = 120 Hz, IAC = 0.1 IR IR = 100 µA 10 Hz ≤ f ≤ 10 kHz t = 1000 hrs T = 25˚C ± 0.1˚C IR = 100 µA ∆T = −40˚C to 125˚C Typical (Note 4) 0.5 93 LM4050AIM3 LM4050BIM3 LM4050CIM3 LM4050AEM3 LM4050BEM3 LM4050CEM3 Limits Limits Limits (Note 5) (Note 5) (Note 5) Units (Limit) Ω µVrms Symbol ZR eN ∆VR 120 1.148 ppm mV VHYST LM4050-5.0 Electrical Characteristics Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2% and 0.5% respectively. Symbol VR Parameter Reverse Breakdown Voltage Reverse Breakdown Voltage Tolerance (Note 6) Conditions IR = 100 µA IR = 100 µA Industrial Temp. Range Extended Temp. Range IRMIN Minimum Operating Current Industrial Temp. Range Extended Temp. Range ∆VR/∆T Average Reverse Breakdown Voltage Temperature Coefficient (Note 6) Reverse Breakdown Voltage Change with Operating Current Change (Note 7) IR = 10 mA IR = 1 mA IR = 100 µA ∆VR/∆IR IRMIN ≤ IR ≤ 1 mA 56 74 80 90 74 80 90 74 80 90 Typical (Note 4) 5.000 LM4050AIM3 LM4050BIM3 LM4050CIM3 LM4050AEM3 LM4050BEM3 LM4050CEM3 Limits Limits Limits (Note 5) (Note 5) (Note 5) Units (Limit) V ± 5.0 ± 22 ± 30 ± 10 ± 27 ± 35 ± 25 ± 42 ± 50 mV (max) mV (max) mV (max) µA µA (max) µA (max) µA (max) ppm/˚C ppm/˚C ± 30 ± 20 ± 20 0.2 1.0 1.4 1.0 1.4 8.0 12.0 1.0 1.4 8.0 12.0 ± 50 ± 50 ± 50 ppm/˚C (max) mV mV (max) mV (max) mV mV (max) mV (max) Ω Ω (max) µVrms 1 mA ≤ IR ≤ 15 mA 2.0 8.0 12.0 ZR eN ∆VR Reverse Dynamic Impedance Wideband Noise Reverse Breakdown Voltage Long Term Stability IR = 1 mA, f = 120 Hz, IAC = 0.1 IR IR = 100 µA 10 Hz ≤ f ≤ 10 kHz t = 1000 hrs T = 25˚C ± 0.1˚C IR = 100 µA ∆T = −40˚C to 125˚C 0.5 93 120 1.4 ppm VHYST Thermal Hysteresis (Note 8) mV www.national.com 6 LM4050 LM4050-8.2 Electrical Characteristics Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1% and ± 0.2% and 0.5% respectively. Symbol VR Parameter Reverse Breakdown Voltage Reverse Breakdown Voltage Tolerance (Note 6) Conditions IR = 150 µA IR = 150 µA Industrial Temp. Range Extended Temp. Range IRMIN Minimum Operating Current Industrial Temp. Range Extended Temp. Range ∆VR/∆T Average Reverse Breakdown Voltage Temperature Coefficient (Note 6) Reverse Breakdown Voltage Change with Operating Current Change (Note 7) IR = 10 mA IR = 1 mA IR = 150 µA ∆VR/∆IR IRMIN ≤ IR ≤ 1 mA 74 91 95 100 91 95 100 91 95 100 Typical (Note 4) 8.192 LM4050AIM3 LM4050BIM3 LM4050CIM3 LM4050AEM3 LM4050BEM3 LM4050CEM3 Limits Limits Limits (Note 5) (Note 5) (Note 5) Units (Limit) V ± 8.2 ± 35 ± 49 ± 16 ± 43 ± 57 ± 41 ± 68 ± 82 mV (max) mV (max) mV (max) µA µA (max) µA (max) µA (max) ppm/˚C ppm/˚C ± 40 ± 20 ± 20 0.6 1.3 2.5 1.3 2.5 10.0 18.0 1.3 2.5 10.0 18.0 ± 50 ± 50 ± 50 ppm/˚C (max) mV mV (max) mV (max) mV mV (max) mV (max) Ω µVrms 1 mA ≤ IR ≤ 15 mA 7.0 10.0 18.0 ZR eN ∆VR Reverse Dynamic Impedance Wideband Noise Reverse Breakdown Voltage Long Term Stability IR = 1 mA, f = 120 Hz, IAC = 0.1 IR IR = 150 µA 10 Hz ≤ f ≤ 10 kHz t = 1000 hrs T = 25˚C ± 0.1˚C IR = 150 µA ∆T = −40˚C to 125˚C 0.6 150 120 2.3 ppm VHYST Thermal Hysteresis (Note 8) mV 7 www.national.com LM4050 LM4050-10.0 Electrical Characteristics Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial Reverse Breakdown Voltage tolerances of ± 0.1% and ± 0.2% and 0.5% respectively. Symbol VR Parameter Reverse Breakdown Voltage Reverse Breakdown Voltage Tolerance (Note 6) Conditions IR = 150 µA IR = 150 µA Industrial Temp. Range Extended Temp. Range IRMIN Minimum Operating Current Industrial Temp. Range Extended Temp. Range ∆VR/∆T Average Reverse Breakdown Voltage Temperature Coefficient (Note 6) Reverse Breakdown Voltage Change with Operating Current Change (Note 7) IR = 10 mA IR = 1 mA IR = 150 µA ∆VR/∆IR IRMIN ≤ IR ≤ 1 mA 80 100 103 110 100 103 110 100 103 110 Typical (Note 4) LM4050AIM3 LM4050BIM3 LM4050CIM3 LM4050AEM3 LM4050BEM3 LM4050CEM3 Limits Limits Limits (Note 5) (Note 5) (Note 5) Units (Limit) V 10.00 ± 10 ± 43 ± 60 ± 20 ± 53 ± 70 ± 50 ± 83 ± 100 mV (max) mV (max) mV (max) µA µA (max) µA (max) µA (max) ppm/˚C ppm/˚C ± 40 ± 20 ± 20 0.8 1.5 3.5 1.5 3.5 12.0 23.0 1.5 3.5 12.0 23.0 ± 50 ± 50 ± 50 ppm/˚C (max) mV mV (max) mV (max) mV mV (max) mV (max) Ω µVrms 1 mA ≤ IR ≤ 15 mA 8.0 12.0 23.0 ZR eN ∆VR Reverse Dynamic Impedance Wideband Noise Reverse Breakdown Voltage Long Term Stability IR = 1 mA, f = 120 Hz, IAC = 0.1 IR IR = 150 µA 10 Hz ≤ f ≤ 10 kHz t = 1000 hrs T = 25˚C ± 0.1˚C IR = 150 µA ∆T = −40˚C to 125˚C 0.7 150 120 2.8 ppm VHYST Thermal Hysteresis (Note 8) mV Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is 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. Some performance characteristics may degrade when the device is not operated under the listed test conditions. Note 2: The maximum power dissipation must be derated at elevated temperatures and is dictated by TJmax (maximum junction temperature), θJA (junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any temperature is PDmax = (TJmax − TA)/θJA or the number given in the Absolute Maximum Ratings, whichever is lower. For the LM4050, TJmax = 125˚C, and the typical thermal resistance (θJA), when board mounted, is 326˚C/W for the SOT-23 package. Note 3: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200 pF capacitor discharged directly into each pin. Note 4: Typicals are at TJ = 25˚C and represent most likely parametric norm. Note 5: Limits are 100% production tested at 25˚C. Limits over temperature are guaranteed through correlation using Statistical Quality Control (SQC) methods. The limits are used to calculate National’s AOQL. Note 6: The boldface (over-temperature) limit for Reverse Breakdown Voltage Tolerance is defined as the room temperature Reverse Breakdown Voltage Tolerance ± [(∆V R/∆T)(max∆T)(VR)]. Where, ∆VR/∆T is the VR temperature coefficient, max∆T is the maximum difference in temperature from the reference point of 25˚C to T MIN or TMAX, and VR is the reverse breakdown voltage. The total over-temperature tolerance for the different grades in the industrial temperature range where max∆T = 65˚C is shown below: A-grade: ± 0.425% = ± 0.1% ± 50 ppm/˚C x 65˚C B-grade: ± 0.525% = ± 0.2% ± 50 ppm/˚C x 65˚C C-grade: ± 0.825% = ± 0.5% ± 50 ppm/˚C x 65˚C Therefore, as an example, the A-grade LM4050-2.5 has an over-temperature Reverse Breakdown Voltage tolerance of ± 2.5V x 0.425% = ± 11 mV. Note 7: Load regulation is measured on pulse basis from no load to the specified load current. Output changes due to die temperature change must be taken into account separately. Note 8: Thermal hysteresis is defined as the difference in voltage measured at +25˚C after cycling to temperature -40˚C and the 25˚C measurement after cycling to temperature +125˚C. www.national.com 8 LM4050 Typical Performance Characteristics Output Impedance vs Frequency Output Impedance vs Frequency 10104510 10104511 Reverse Characteristics and Minimum Operating Current Noise Voltage vs Frequency 10104512 10104513 Thermal Hysteresis 10104529 9 www.national.com LM4050 Start-Up Characteristics LM4050-10.0 RS = 30k 10104505 LM4050-2.5 RS = 30k 10104509 10104507 LM4050-5.0 RS = 30k 10104508 www.national.com 10 LM4050 Functional Block Diagram 10104514 Applications Information The LM4050 is a precision micro-power curvature-corrected bandgap shunt voltage reference. For space critical applications, the LM4050 is available in the sub-miniature SOT-23 surface-mount package. The LM4050 has been designed for stable operation without the need of an external capacitor connected between the “+” pin and the “−” pin. If, however, a bypass capacitor is used, the LM4050 remains stable. Reducing design effort is the availability of several fixed reverse breakdown voltages: 2.048V, 2.500V, 4.096V, 5.000V, 8.192V, and 10.000V. The minimum operating current increases from 60 µA for the LM4050-2.0 to 100 µA for the LM4050-10.0. All versions have a maximum operating current of 15 mA. LM4050s in the SOT-23 packages have a parasitic Schottky diode between pin 2 (−) and pin 3 (Die attach interface contact). Therefore, pin 3 of the SOT-23 package must be left floating or connected to pin 2. The 4.096V version allows single +5V 12-bit ADCs or DACs to operate with an LSB equal to 1 mV. For 12-bit ADCs or DACs that operate on supplies of 10V or greater, the 8.192V version gives 2 mV per LSB. The typical thermal hysteresis specification is defined as the change in +25˚C voltage measured after thermal cycling. The device is thermal cycled to temperature -40˚C and then measured at 25˚C. Next the device is thermal cycled to temperature +125˚C and again measured at 25˚C. The resulting VOUT delta shift between the 25˚C measurements is thermal hysteresis. Thermal hysteresis is common in precision references and is induced by thermal-mechanical package stress. Changes in environmental storage temperature, operating temperature and board mounting temperature are all factors that can contribute to thermal hysteresis. In a conventional shunt regulator application (Figure 1) , an external series resistor (RS) is connected between the supply voltage and the LM4050. RS determines the current that flows through the load (IL) and the LM4050 (IQ). Since load current and supply voltage may vary, RS should be small enough to supply at least the maximum guaranteed IRMIN (spec. table) to the LM4050 even when the supply voltage is at its minimum and the load current is at its maximum value. When the supply voltage is at its maximum and IL is at its minimum, RS should be large enough so that the current flowing through the LM4050 is less than 15 mA. RS is determined by the supply voltage, (VS), the load and operating current, (IL and IQ), and the LM4050’s reverse breakdown voltage, VR. Typical Applications 10104515 FIGURE 1. Shunt Regulator 11 www.national.com LM4050 Typical Applications (Continued) 10104516 **Ceramic monolithic *Tantalum FIGURE 2. LM4050-4.1’s Nominal 4.096 breakdown voltage gives ADC12451 1 mV/LSB www.national.com 12 LM4050 Typical Applications (Continued) 10104517 FIGURE 3. Bounded amplifier reduces saturation-induced delays and can prevent succeeding stage damage. Nominal clamping voltage is ± 11.5V (LM4050’s reverse breakdown voltage +2 diode VF). 10104518 FIGURE 4. Protecting Op Amp input. The bounding voltage is ± 4V with the LM4050-2.5 (LM4050’s reverse breakdown voltage + 3 diode VF). 13 www.national.com LM4050 Typical Applications (Continued) 10104519 FIGURE 5. Precision ± 4.096V Reference 10104521 10104522 FIGURE 6. Precision 1 µA to 1 mA Current Sources www.national.com 14 LM4050 Precision Micropower Shunt Voltage Reference Physical Dimensions inches (millimeters) unless otherwise noted Plastic Surface Mount Package (M3) NS Package Number MF03A (JEDEC Registration TO-236AB) 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. BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. National Semiconductor Americas Customer Support Center Email: new.feedback@nsc.com Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Customer Support Center 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 Support Center Email: ap.support@nsc.com National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: jpn.feedback@nsc.com Tel: 81-3-5639-7560 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 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.