LP2950/LP2951 Series of Adjustable Micropower Voltage Regulators General Description The LP2950 and LP2951 are micropower voltage regulators with very low quiescent current (75 A typ.) and very low dropout voltage (typ. 40 mV at light loads and 380 mV at 100 mA). They are ideally suited for use in battery-powered systems. Furthermore, the quiescent current of the LP2950/ LP2951 increases only slightly in dropout, prolonging battery life. The LP2950-5.0 is available in the surface-mount D-Pak package, and in the popular 3-pin TO-92 package for pin-compatibility with older 5V regulators. The 8-lead LP2951 is available in plastic, ceramic dual-in-line, or metal can packages and offers additional system functions. One such feature is an error flag output which warns of a low output voltage, often due to falling batteries on the input. It may be used for a power-on reset. A second feature is the logic-compatible shutdown input which enables the regulator to be switched on and off. Also, the part may be pin-strapped for a 5V, 3V, or 3.3V output (depending on the version), or programmed from 1.24V to 29V with an external pair of resistors. Careful design of the LP2950/LP2951 has minimized all contributions to the error budget. This includes a tight initial tolerance (.5% typ.), extremely good load and line regulation (.05% typ.) and a very low output voltage temperature coefficient, making the part useful as a low-power voltage reference. Features n n n n n n n n n n n 5V, 3V, and 3.3V versions available High accuracy output voltage Guaranteed 100 mA output current Extremely low quiescent current Low dropout voltage Extremely tight load and line regulation Very low temperature coefficient Use as Regulator or Reference Needs minimum capacitance for stability Current and Thermal Limiting Stable with low-ESR output capacitors LP2951 versions only n Error flag warns of output dropout n Logic-controlled electronic shutdown n Output programmable from 1.24 to 29V Block Diagram and Typical Applications LP2950 LP2951 DS008546-25 DS008546-1 (c) 2000 National Semiconductor Corporation DS008546 www.national.com LP2950/LP2951 Series of Adjustable Micropower Voltage Regulators July 2000 LP2950/LP2951 Connection Diagrams TO-92 Plastic Package (Z) Dual-In-Line Packages (N, J) Surface-Mount Package (M, MM) DS008546-2 Bottom View DS008546-26 Top View Metal Can Package (H) 10-Lead Ceramic Surface-Mount Package (WG) DS008546-64 Top View DS008546-19 Top View TO-252 (D-Pak) DS008546-70 Front View www.national.com 2 LP2950/LP2951 Ordering Information Package Output Voltage 3.0V TO-92 (Z) 3.3V Temperature 5.0V LP2950ACZ-3.0 LP2950ACZ-3.3 LP2950ACZ-5.0 (C) -40 < TJ < 125 LP2950CZ-3.0 LP2950CZ-3.3 LP2950CZ-5.0 TO-252 (D-Pak) LP2950CDT-3.0 LP2950CDT-3.3 LP2950CDT-5.0 -40 < TJ < 125 N (N-08E) LP2951ACN-3.0 LP2951ACN-3.3 LP2951ACN -40 < TJ < 125 LP2951CN-3.0 LP2951CN-3.3 LP2951CN LP2951ACM-3.0 LP2951ACM-3.3 LP2951ACM LP2951CM-3.0 LP2951CM-3.3 LP2951CM LP2951ACMM-3.0 LP2951ACMM-3.3 LP2951ACMM LP2951CMM-3.0 LP2951CMM-3.3 M (M08A) MM (MUA08A) in Tape and Reel J (J08A) -40 < TJ < 125 -40 < TJ < 125 LP2951CMM LP2951ACJ -40 < TJ < 125 LP2951CJ LP2951J -55 < TJ < 150 LP2951J/883 5926-3870501MPA H (H08C) LP2951H/883 -55 < TJ < 150 5962-3870501MGA WG (WG10A) LP2951WG/883 -55 < TJ < 150 5962-3870501MXA Package Marking for MM Package: Order Number Package Marking LP2951ACMM L0DA LP2951CMM L0DB LP2951ACMM-3.3 L0CA LP2951CMM-3.3 L0CB LP2951ACMM-3.0 L0BA LP2951CMM-3.0 L0BB 3 www.national.com LP2950/LP2951 Absolute Maximum Ratings (Note 1) Soldering Dwell Time, Temperature Wave Infrared Vapor Phase ESD If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Input Supply Voltage SHUTDOWN Input Voltage, Error Comparator Output Voltage, (Note 9) FEEDBACK Input Voltage (Note 9) (Note 10) Power Dissipation Junction Temperature (TJ) Ambient Storage Temperature -0.3 to +30V 4 seconds, 260C 10 seconds, 240C 75 seconds, 219C TBD Operating Ratings (Note 1) Maximum Input Supply Voltage Junction Temperature Range (TJ) (Note 8) LP2951 LP2950AC-XX, LP2950C-XX, LP2951AC-XX, LP2951C-XX -1.5 to +30V Internally Limited +150C -65 to +150C 30V -55 to +150C -40 to +125C Electrical Characteristics (Note 2) LP2951 Parameter Conditions (Note 2) Tested Typ Limit Typ (Notes 3, 16) LP2950AC-XX LP2950C-XX LP2951AC-XX LP2951C-XX Tested Design Limit Limit (Note 3) (Note 4) Typ Tested Design Limit Limit (Note 3) (Note 4) Units 3V VERSIONS (Note 17) Output Voltage TJ = 25C 3.0 3.015 3.0 2.985 -25C TJ 85C 3.0 Full Operating 3.0 3.015 3.0 2.985 3.0 3.030 3.030 Temperature Range Output Voltage 100 A IL 100 mA 3.0 3.036 2.964 3.0 TJ TJMAX 3.045 3.045 2.955 V min 3.0 3.060 V max 2.940 V min 3.0 3.072 V max 2.928 V min 2.964 3.0 3.042 2.955 V min 3.0 2.970 3.036 V max 2.970 2.958 V max 3.3V VERSIONS (Note 17) Output Voltage TJ = 25C 3.3 3.317 3.3 3.284 -25C TJ 85C 3.3 Full Operating 3.3 3.317 3.3 3.284 3.3 3.333 3.333 Temperature Range Output Voltage 100 A IL 100 mA 3.3 3.340 3.260 3.3 TJ TJMAX 3.350 3.350 3.251 V min 3.3 3.366 V max 3.234 V min 3.3 3.379 V max 3.221 V min 3.260 3.3 3.346 3.251 V min 3.3 3.267 3.340 V max 3.267 3.254 V max 5V VERSIONS (Note 17) Output Voltage TJ = 25C 5.0 5.025 5.0 4.975 -25C TJ 85C 5.0 Full Operating 5.0 5.06 5.0 5.075 5.025 5.0 4.975 5.05 5.0 5.05 5.0 5.06 5.0 5.075 5.0 Temperature Range 100 A IL 100 mA 4.94 TJ TJMAX V max 4.925 V min 5.0 5.1 V max 4.9 V min 5.0 5.12 V max 4.88 V min 150 ppm/C 4.94 4.925 V min 5.075 4.95 Output Voltage V max 4.95 4.925 ALL VOLTAGE OPTIONS Output Voltage Temperature Coefficient (Note 12) Line Regulation (Note 14) (VONOM + 1)V Vin 30V (Note 15) 0.03 Load Regulation (Note 14) 100 A IL 100 mA 0.04 www.national.com 20 120 20 0.1 0.03 100 0.1 0.5 50 0.04 0.2 0.2 0.1 0.04 0.3 0.1 0.1 0.2 4 % max 0.4 % max 0.3 % max 0.2 % max (Continued) LP2951 Parameter Conditions (Note 2) Tested Typ Limit Typ (Notes 3, 16) LP2950AC-XX LP2950C-XX LP2951AC-XX LP2951C-XX Tested Design Limit Limit (Note 3) (Note 4) Typ Tested Design Limit Limit (Note 3) (Note 4) Units ALL VOLTAGE OPTIONS Dropout Voltage (Note 5) IL = 100 A 80 50 IL = 100 mA IL = 100 A 75 Current 80 50 450 380 Ground 80 150 150 450 600 380 120 75 8 600 8 120 75 12 8 14 Dropout Vin = (VONOM - 0.5)V Ground Current IL = 100 A Current Limit Vout = 0 110 110 170 110 200 160 160 200 160 220 0.05 140 A max 14 mA max 200 A max 220 mA max 12 mA max 170 A max 200 mA max 220 0.2 mV max A max 200 200 600 120 14 170 mV max mV max 380 140 12 150 450 140 IL = 100 mA mV max 50 Thermal Regulation (Note 13) 0.05 Output Noise, CL = 1 F (5V Only) 430 430 0.2 0.05 430 0.2 %/W max V rms 10 Hz to 100 kHz CL = 200 F 160 160 160 V rms 100 100 100 V rms CL = 3.3 F (Bypass = 0.01 F Pins 7 to 1 (LP2951)) 8-PIN VERSIONS ONLY LP2951 Reference 1.235 Voltage LP2951AC-XX 1.25 1.235 1.26 (Note 7) Voltage Feedback Pin 20 Bias Current Reference Voltage 1.26 1.22 V max 1.27 V max 1.21 V min 1.2 1.2 1.2 V min 1.27 1.27 1.285 V max 1.19 1.19 1.185 40 20 40 60 (Note 12) 1.235 1.26 1.22 Reference LP2951C-XX 1.25 20 40 60 V min nA max 60 nA max 20 20 50 ppm/C 0.1 0.1 0.1 nA/C Temperature Coefficient Feedback Pin Bias Current Temperature Coefficient Error Comparator Output Leakage VOH = 30V 0.01 Current Output Low Vin = (VONOM - 0.5)V Voltage IOL = 400 A Upper Threshold (Note 6) 150 60 1 (Note 6) 75 250 150 1 250 150 40 60 40 60 75 95 75 140 15 15 A max 400 mV max 25 mV min 140 mV max mV max 40 25 95 A max 2 250 400 140 (Note 6) 0.01 2 25 Voltage Hysteresis 0.01 400 Voltage Lower Threshold 1 2 mV min 95 mV max 15 mV Shutdown Input Input 1.3 1.3 1.3 V Logic Low (Regulator ON) 0.6 0.7 0.7 V max Voltage High (Regulator OFF) 2.0 2.0 2.0 V min 5 www.national.com LP2950/LP2951 Electrical Characteristics (Note 2) LP2950/LP2951 Electrical Characteristics (Note 2) (Continued) LP2951 Parameter Conditions (Note 2) Tested Typ Limit Typ (Notes 3, 16) LP2950AC-XX LP2950C-XX LP2951AC-XX LP2951C-XX Tested Design Limit Limit (Note 3) (Note 4) Typ Tested Design Limit Limit (Note 3) (Note 4) Units Shutdown Input Shutdown Pin Input Current Vshutdown = 2.4V 30 50 30 50 100 Vshutdown = 30V 450 600 450 600 750 Regulator Output Current in Shutdown (Note 11) 3 30 50 100 450 10 3 10 3 20 A max 750 A max 20 A max 600 750 20 A max 100 A max 10 A max Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical Characteristics tables. Note 2: Unless otherwise specified all limits guaranteed for VIN = (VONOM + 1)V, IL = 100 A and CL = 1 F for 5V versions and 2.2 F for 3V and 3.3V versions. Limits appearing in boldface type apply over the entire junction temperature range for operation. Limits appearing in normal type apply for TA = TJ = 25C. Additional conditions for the 8-pin versions are FEEDBACK tied to VTAP, OUTPUT tied to SENSE, and VSHUTDOWN 0.8V. Note 3: Guaranteed and 100% production tested. Note 4: Guaranteed but not 100% production tested. These limits are not used to calculate outgoing AQL levels. Note 5: Dropout Voltage is defined as the input to output differential at which the output voltage drops 100 mV below its nominal value measured at 1V differential. At very low values of programmed output voltage, the minimum input supply voltage of 2V (2.3V over temperature) must be taken into account. Note 6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal reference voltage measured at Vin = (VONOM + 1)V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = Vout/Vref = (R1 + R2)/R2. For example, at a programmed output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x 5V/1.235V = 384 mV. Thresholds remain constant as a percent of Vout as Vout is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed. Note 7: Vref Vout (Vin - 1V), 2.3V Vin 30V, 100 A IL 100 mA, TJ TJMAX. Note 8: The junction-to-ambient thermal resistances are as follows: 180C/W and 160C/W for the TO-92 package with 0.40 inch and 0.25 inch leads to the printed circuit board (PCB) respectively, 105C/W for the molded plastic DIP (N), 130C/W for the ceramic DIP (J), 160C/W for the molded plastic SOP (M), 200C/W for the molded plastic MSOP (MM), and 160C/W for the metal can package (H). The above thermal resistances for the N, J, M, and MM packages apply when the package is soldered directly to the PCB. Junction-to-case thermal resistance for the H package is 20C/W. Junction-to-case thermal resistance for the TO-252 package is 5.4C/W. Note 9: May exceed input supply voltage. Note 10: When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the output voltage should be diode-clamped to ground. Note 11: Vshutdown 2V, Vin 30V, Vout = 0, Feedback pin tied to VTAP. Note 12: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range. Note 13: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN = 30V (1.25W pulse) for T = 10 ms. Note 14: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation. Note 15: Line regulation for the LP2951 is tested at 150C for IL = 1 mA. For IL = 100 A and TJ = 125C, line regulation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus temperature and load current. Note 16: A Military RETS specification is available on request. At time of printing, the LP2951 RETS specification complied with the boldface limits in this column. The LP2951H, WG, or J may also be procured as Standard Military Drawing Spec #5962-3870501MGA, MXA, or MPA. Note 17: All LP2950 devices have the nominal output voltage coded as the last two digits of the part number. In the LP2951 products, the 3.0V and 3.3V versions are designated by the last two digits, but the 5V version is denoted with no code at this location of the part number (refer to ordering information table). Typical Performance Characteristics Quiescent Current Dropout Characteristics DS008546-28 DS008546-27 www.national.com Input Current 6 DS008546-29 Input Current LP2950/LP2951 Typical Performance Characteristics (Continued) Output Voltage vs. Temperature of 3 Representative Units Quiescent Current DS008546-30 DS008546-32 DS008546-31 Quiescent Current Quiescent Current DS008546-33 Short Circuit Current Quiescent Current DS008546-35 DS008546-34 Dropout Voltage Dropout Voltage DS008546-36 DS008546-37 7 DS008546-38 www.national.com LP2950/LP2951 Typical Performance Characteristics LP2951 Minimum Operating Voltage (Continued) LP2951 Feedback Bias Current DS008546-39 LP2951 Error Comparator Output LP2951 Feedback Pin Current DS008546-40 LP2951 Comparator Sink Current DS008546-41 Line Transient Response DS008546-44 DS008546-42 Load Transient Response DS008546-43 Load Transient Response DS008546-45 LP2951 Enable Transient DS008546-46 DS008546-47 www.national.com 8 Output Impedance (Continued) Ripple Rejection Ripple Rejection DS008546-48 Ripple Rejection DS008546-49 LP2951 Output Noise DS008546-51 Shutdown Threshold Voltage LP2950/LP2951 Typical Performance Characteristics DS008546-50 LP2951 Divider Resistance DS008546-52 Line Regulation DS008546-53 LP2951 Maximum Rated Output Current DS008546-54 DS008546-55 DS008546-56 LP2950 Maximum Rated Output Current Thermal Response Output Capacitor ESR Range DS008546-58 DS008546-57 DS008546-63 9 www.national.com LP2950/LP2951 Application Hints EXTERNAL CAPACITORS sistor, note that while the output is rated to sink 400 A, this sink current adds to battery drain in a low battery condition. Suggested values range from 100k to 1 M. The resistor is not required if this output is unused. A 1.0 F (or greater) capacitor is required between the output and ground for stability at output voltages of 5V or more. At lower output voltages, more capacitance is required (2.2 F or more is recommended for 3V and 3.3V versions). Without this capacitor the part will oscillate. Most types of tantalum or aluminum electrolytics work fine here; even film types work but are not recommended for reasons of cost. Many aluminum electrolytics have electrolytes that freeze at about -30C, so solid tantalums are recommended for operation below -25C. The important parameters of the capacitor are an ESR of about 5 or less and a resonant frequency above 500 kHz. The value of this capacitor may be increased without limit. At lower values of output current, less output capacitance is required for stability. The capacitor can be reduced to 0.33 F for currents below 10 mA or 0.1 F for currents below 1 mA. Using the adjustable versions at voltages below 5V runs the error amplifier at lower gains so that more output capacitance is needed. For the worst-case situation of a 100 mA load at 1.23V output (Output shorted to Feedback) a 3.3 F (or greater) capacitor should be used. Unlike many other regulators, the LP2950 will remain stable and in regulation with no load in addition to the internal voltage divider. This is especially important in CMOS RAM keep-alive applications. When setting the output voltage of the LP2951 versions with external resistors, a minimum load of 1 A is recommended. A 1 F tantalum or aluminum electrolytic capacitor should be placed from the LP2950/LP2951 input to ground if there is more than 10 inches of wire between the input and the AC filter capacitor or if a battery is used as the input. Stray capacitance to the LP2951 Feedback terminal can cause instability. This may especially be a problem when using high value external resistors to set the output voltage. Adding a 100 pF capacitor between Output and Feedback and increasing the output capacitor to at least 3.3 F will fix this problem. DS008546-20 *When VIN 1.3V, the error flag pin becomes a high impedance, and the error flag voltage rises to its pull-up voltage. Using VOUT as the pull-up voltage (see Figure 2), rather than an external 5V source, will keep the error flag voltage under 1.2V (typ.) in this condition. The user may wish to divide down the error flag voltage using equal-value resistors (10 k suggested), to ensure a low-level logic signal during any fault condition, while still allowing a valid high logic level during normal operation. FIGURE 1. ERROR Output Timing PROGRAMMING THE OUTPUT VOLTAGE (LP2951) The LP2951 may be pin-strapped for the nominal fixed output voltage using its internal voltage divider by tying the output and sense pins together, and also tying the feedback and VTAP pins together. Alternatively, it may be programmed for any output voltage between its 1.235V reference and its 30V maximum rating. As seen in Figure 2, an external pair of resistors is required. The complete equation for the output voltage is where VREF is the nominal 1.235 reference voltage and IFB is the feedback pin bias current, nominally -20 nA. The minimum recommended load current of 1 A forces an upper limit of 1.2 M on the value of R2, if the regulator must work with no load (a condition often found in CMOS in standby). IFB will produce a 2% typical error in VOUT which may be eliminated at room temperature by trimming R1. For better accuracy, choosing R2 = 100k reduces this error to 0.17% while increasing the resistor program current to 12 A. Since the LP2951 typically draws 60 A at no load with Pin 2 open-circuited, this is a small price to pay. ERROR DETECTION COMPARATOR OUTPUT The comparator produces a logic low output whenever the LP2951 output falls out of regulation by more than approximately 5%. This figure is the comparator's built-in offset of about 60 mV divided by the 1.235 reference voltage. (Refer to the block diagram in the front of the datasheet.) This trip level remains "5% below normal" regardless of the programmed output voltage of the 2951. For example, the error flag trip level is typically 4.75V for a 5V output or 11.4V for a 12V output. The out of regulation condition may be due either to low input voltage, current limiting, or thermal limiting. Figure 1 below gives a timing diagram depicting the ERROR signal and the regulated output voltage as the LP2951 input is ramped up and down. For 5V versions, the ERROR signal becomes valid (low) at about 1.3V input. It goes high at about 5V input (the input voltage at which VOUT = 4.75V). Since the LP2951's dropout voltage is load-dependent (see curve in typical performance characteristics), the input voltage trip point (about 5V) will vary with the load current. The output voltage trip point (approx. 4.75V) does not vary with load. The error comparator has an open-collector output which requires an external pullup resistor. This resistor may be returned to the output or some other supply voltage depending on system requirements. In determining a value for this rewww.national.com 10 LP2950/LP2951 Application Hints (Continued) DS008546-7 *See Application Hints **Drive with TTL-high to shut down. Ground or leave open if shutdown feature is not to be used. Note: Pins 2 and 6 are left open. FIGURE 2. Adjustable Regulator REDUCING OUTPUT NOISE In reference applications it may be advantageous to reduce the AC noise present at the output. One method is to reduce the regulator bandwidth by increasing the size of the output capacitor. This is the only way noise can be reduced on the 3 lead LP2950 but is relatively inefficient, as increasing the capacitor from 1 F to 220 F only decreases the noise from 430 V to 160 V rms for a 100 kHz bandwidth at 5V output. Noise can be reduced fourfold by a bypass capacitor across R1, since it reduces the high frequency gain from 4 to unity. Pick or about 0.01 F. When doing this, the output capacitor must be increased to 3.3 F to maintain stability. These changes reduce the output noise from 430 V to 100 V rms for a 100 kHz bandwidth at 5V output. With the bypass capacitor added, noise no longer scales with output voltage so that improvements are more dramatic at higher output voltages. 11 www.national.com LP2950/LP2951 Typical Applications 1A Regulator with 1.2V Dropout DS008546-22 300 mA Regulator with 0.75V Dropout Wide Input Voltage Range Current Limiter DS008546-9 DS008546-21 *Minimum input-output voltage ranges from 40 mV to 400 mV, depending on load current. Current limit is typically 160 mA. Low Drift Current Source 5 Volt Current Limiter DS008546-10 *Minimum input-output voltage ranges from 40 mV to 400 mV, depending on load current. Current limit is typically 160 mA. DS008546-8 www.national.com 12 LP2950/LP2951 Typical Applications (Continued) Regulator with Early Warning and Auxiliary Output Latch Off When Error Flag Occurs DS008546-12 DS008546-11 j Early warning flag on low input voltage j Main output latches off at lower input voltages j Battery backup on auxiliary output Operation: Reg. #1's Vout is programmed one diode drop above 5V. Its error flag becomes active when Vin 5.7V. When Vin drops below 5.3V, the error flag of Reg. #2 becomes active and via Q1 latches the main output off. When Vin again exceeds 5.7V Reg. #1 is back in regulation and the early warning signal rises, unlatching Reg. #2 via D3. 13 www.national.com LP2950/LP2951 Typical Applications (Continued) 2 Ampere Low Dropout Regulator DS008546-13 For 5Vout, use internal resistors. Wire pin 6 to 7, & wire pin 2 to +Vout Bus. Open Circuit Detector for 4 20 mA Current Loop 5V Regulator with 2.5V Sleep Function DS008546-15 DS008546-14 *High input lowers Vout to 2.5V www.national.com 14 LP2950/LP2951 Typical Applications (Continued) Regulator with State-of-Charge Indicator DS008546-16 *Optional Latch off when drop out occurs. Adjust R3 for C2 Switching when Vin is 6.0V. **Outputs go low when Vin drops below designated thresholds. Low Battery Disconnect DS008546-17 For values shown, Regulator shuts down when Vin *Sets disconnect Voltage **Sets disconnect Hysteresis < 5.5V and turns on again at 6.0V. Current drain in disconnected mode is 150 A. 15 www.national.com LP2950/LP2951 Typical Applications (Continued) System Overtemperature Protection Circuit DS008546-18 LM34 for 125F Shutdown LM35 for 125C Shutdown www.national.com 16 DS008546-23 17 www.national.com LP2950/LP2951 Schematic Diagram LP2950/LP2951 Physical Dimensions inches (millimeters) unless otherwise noted Order Number LP2951WG/883 or 5962-3870501MXA NS Package Number WG10A Metal Can Package (H) Order Number LP2951H/883 or 5962-3870501MGA NS Package Number H08C www.national.com 18 LP2950/LP2951 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Ceramic Dual-In-Line Package (J) Order Number LP2951CJ, LP2951ACJ, LP2951J, LP2951J/883 or 5962-3870501MPA NS Package Number J08A Surface Mount Package (M) Order Number LP2951ACM, LP2951CM, LP2951ACM-3.0, LP2951CM-3.0, LP2951ACM-3.3 or LP2951CM-3.3 NS Package Number M08A 19 www.national.com LP2950/LP2951 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Molded Dual-In-Line Package (N) Order Number LP2951ACN, LP2951CN, LP2951ACN-3.0, LP2951CN-3.0, or LP2951ACN-3.3 or LP2951CN-3.3 NS Package Number N08E Molded TO-92 Package (Z) Order Number LP2950ACZ-3.0 or LP2950CZ-3.0, LP2950ACZ-3.3, LP2950CZ-3.3, LP2950ACZ-5.0 or LP2950CZ-5.0 NS Package Number Z03A www.national.com 20 LP2950/LP2951 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Surface Mount Package (MM) Order Number LP2951ACMM, LP2951CMM, LP2951ACMM-3.0, LP2951CMM-3.0, LP2951ACMM-3.3 or LP2951CMM-3.3 NS Package Number MUA08A D-Pak Package Order Number LP2950CDT-3.0, LP2950CDT-3.3, or LP2950CDT-5.0 NS Package Number TD03B 21 www.national.com LP2950/LP2951 Series of Adjustable Micropower Voltage Regulators 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: support@nsc.com www.national.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 Francais 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. 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 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. National P/N LP2951 - Series of Adjustable Micropower Voltage Regulators See A/D Converters Products Products > Analog - Regulators > Linear Regulators - Low Dropout Voltage > Positive Voltage - Adjustable > LP2951 LP2951 Product Folder Series of Adjustable Micropower Voltage Regulators Generic P/N 2951 General Description Features Package & Models Datasheet Parametric Table Samples & Pricing Application Notes Parametric Table Multiple Output Capability No Dropout Voltage, typ (Volt) .38 On/Off Pin Yes Quiescent Current, typ (mA) .0750 Error Flag Yes Secondary Ouput Voltage (Volt) - Input Voltage, min (Volt) -.30 Secondary Output Current (Amp) - Input Voltage, max (Volt) 30 Output Voltage, min (Volt) 1.24, 1.2350 Output Current, max 100 mA Output Voltage, max (Volt) 29, 29.50 Watchdog No Datasheet Size in Date Kbytes Title View Online Download Receive via Email 14657 JulKbytes 00 View Online Download Receive via Email 704 Kbytes View Online Download LP2951 Mil-Aero (JAN) Datasheet MJLP2951-X 268 Kbytes View Online Download Receive via Email LP2951 Mil-Aero Datasheet MNLP2951-X 267 Kbytes View Online Download Receive via Email LP2950 LP2951 Series of Adjustable Micropower Voltage Regulators LP2950 LP2951 Series of Adjustable Micropower Voltage Regulators (JAPANESE) Receive via Email If you have trouble printing or viewing PDF file(s), see Printing Problems. Package Availability, Models, Samples & Pricing Part Number Package Type Pins MSL Status Samples & Electronic Orders SPICE IBIS Models Budgetary Pricing Qty Std Pack $US each Size Package Marking file:///H|/imaging/BITTING/cpl/20020808_1/08062002_10/NATL/08062002_HTML/LP2951.html (1 of 6) [09-Aug-2002 9:39:38 AM] National P/N LP2951 - Series of Adjustable Micropower Voltage Regulators N/A N/A 24 Hour Samples Buy Now 1K+ $0.3100 rail of 95 [logo]2T 2951 ACMD Full production N/A 24 Hour N/A Samples Buy Now 1K+ $0.3100 rail of 95 [logo]2T 2951A CM30D Full production N/A N/A 1K+ $0.3100 rail of 95 [logo]2T 2951A CM33D Full production N/A N/A 24 Hour Samples Buy Now 1K+ $0.2800 rail of 95 [logo]2T 2951 CMD N/A 24 Hour N/A Samples Buy Now 1K+ $0.2800 rail of 95 [logo]2T 2951C M30D Full production N/A 24 Hour N/A Samples Buy Now 1K+ $0.2800 rail of 95 [logo]2T 2951C M33D MSL Full production N/A N/A 1K+ $0.3100 reel of 2500 [logo]2T 2951 ACMD 8 MSL Full production N/A N/A 1K+ $0.3100 reel of 2500 [logo]2T 2951A CM30D SOIC NARROW 8 MSL Full production N/A N/A Buy Now 1K+ $0.3100 reel of 2500 [logo]2T 2951A CM33D LP2951CMX SOIC NARROW 8 MSL Full production N/A N/A Buy Now 1K+ $0.2800 reel of 2500 [logo]2T 2951 CMD LP2951CMX-3.0 SOIC NARROW 8 MSL Full production N/A N/A 1K+ $0.2800 reel of 2500 [logo]2T 2951C M30D LP2951CMX-3.3 SOIC NARROW 8 MSL Full production N/A N/A 1K+ $0.2800 reel of 2500 [logo]2T 2951C M33D MINI SOIC 8 MSL Full production N/A N/A 1K+ $0.3980 reel of 1000 Z1T L0DA LP2951ACMM3.0 MINI SOIC 8 MSL Full production N/A 1K+ $0.3980 reel of 1000 Z1T L0BA LP2951ACMM3.3 MINI SOIC 8 MSL 1K+ $0.3980 reel of 1000 Z1T L0CA SOIC NARROW 8 MSL Full production SOIC LP2951ACM-3.0 NARROW 8 MSL LP2951ACM-3.3 SOIC NARROW 8 MSL LP2951CM SOIC NARROW 8 MSL LP2951CM-3.0 SOIC NARROW 8 Full MSL production LP2951CM-3.3 SOIC NARROW 8 MSL LP2951ACMX SOIC NARROW 8 LP2951ACMX3.0 SOIC NARROW LP2951ACMX3.3 LP2951ACM LP2951ACMM Full production Samples Buy Now Buy Now Buy Now Buy Now Samples Buy Now Samples N/A Buy Now Samples N/A N/A Buy Now file:///H|/imaging/BITTING/cpl/20020808_1/08062002_10/NATL/08062002_HTML/LP2951.html (2 of 6) [09-Aug-2002 9:39:38 AM] National P/N LP2951 - Series of Adjustable Micropower Voltage Regulators 1K+ $0.3650 reel of 1000 Z1T L0DB 1K+ $0.3650 reel of 1000 Z1T L0BB 1K+ $0.3650 reel of 1000 Z1T L0CB N/A 1K+ $0.3980 reel of 3500 Z1T L0DA N/A N/A 1K+ $0.3980 reel of 3500 Z1T L0BA Full production N/A N/A 1K+ $0.3980 reel of 3500 Z1T L0CA MSL Full production N/A N/A 1K+ $0.3650 reel of 3500 Z1T L0DB 8 MSL Full production N/A N/A 1K+ $0.3650 reel of 3500 Z1T L0BB 8 MSL Full production N/A N/A 1K+ $0.3650 reel of 3500 Z1T L0CB LP2951ACN MDIP 8 MSL Full production N/A 24 Hour N/A Samples Buy Now 1K+ $0.3400 rail of 40 [logo]UZ2T LP 2951ACN LP2951ACN-3.0 MDIP 8 MSL Full production N/A N/A 1K+ $0.3400 rail of 40 [logo]UZ2T LP2951 ACN-3.0 LP2951ACN-3.3 MDIP 8 MSL Full production N/A N/A 24 Hour Samples Buy Now 1K+ $0.3400 rail of 40 [logo]UZ2T LP2951 ACN-3.3 LP2951CN MDIP 8 MSL Full production N/A N/A 24 Hour Samples Buy Now 1K+ $0.3650 rail of 40 [logo]UZ2T LP 2951CN LP2951CN-3.0 MDIP 8 MSL Full production N/A N/A 24 Hour Samples Buy Now 1K+ $0.3650 rail of 40 [logo]UZ2T LP2951 CN-3.0 8 Full MSL production N/A 24 Hour N/A Samples Buy Now 1K+ $0.3650 rail of 40 [logo]UZ2T LP2951 CN-3.3 20 Full MSL production $24.2000 rail of 50 [logo]ZS4A LP2951E/883 QM$E 59623870501M2A MINI SOIC 8 LP2951CMM3.0 MINI SOIC 8 MSL LP2951CMM3.3 MINI SOIC 8 MSL LP2951ACMMX MINI SOIC 8 LP2951ACMMX3.0 MINI SOIC LP2951ACMMX3.3 Samples Full production N/A Full production N/A N/A Full production N/A N/A MSL Full production N/A 8 MSL Full production MINI SOIC 8 MSL LP2951CMMX MINI SOIC 8 LP2951CMMX3.0 MINI SOIC LP2951CMMX3.3 MINI SOIC LP2951CMM LP2951CN-3.3 59623870501M2A MDIP LCC MSL N/A Buy Now Samples Buy Now Samples N/A N/A Buy Now Buy Now Buy Now 25+ file:///H|/imaging/BITTING/cpl/20020808_1/08062002_10/NATL/08062002_HTML/LP2951.html (3 of 6) [09-Aug-2002 9:39:38 AM] National P/N LP2951 - Series of Adjustable Micropower Voltage Regulators 59623870501MGA 59623870501MPA TO-5 CERDIP 8 Full MSL production 8 Full MSL production N/A N/A N/A Ceramic SOIC 10 MSL Full production N/A N/A LP2951H-MCP TO-5 8 MSL Full production N/A N/A 8 Full MSL production 20 Full MSL production 59623870501BPA 59623870501S2A CERDIP LCC RM2951JXQMLV CERDIP 59623870501SPA CERDIP N/A N/A $13.7000 rail of 40 [logo]ZS4A$E LP2951J/883 Q 59623870501MPA 25+ $16.9000 tray of 54 [logo] $E ZS4A LP2951WG /Q5962-38 70501MXA 250+ $8.3500 25+ Buy Now tray [logo]ZS4A$E of LP2951H-MCP 20 rail of 40 [logo] 59623870501BPA 27014 Q ZS4A$E rail of 50 [logo]ZS4A 27014 QM$E 59623870501S2A N/A rail of N/A [logo]ZS4A$E RM2951JX QMLV WAFER# R rail of 40 [logo]ZS4A$E 27014 Q 59623870501SPA N/A Buy Now N/A 8 MSL Preliminary 8 Full MSL production N/A N/A N/A [logo] ZS4A LP2951H/883QM 59623870501MGA $E 25+ N/A 59623870501MXA $22.8000 tray of 20 50+ $35.2000 50+ $225.0000 50+ $207.0000 LP2951C MDC Die Full production N/A N/A Samples tray of N/A - LP2951C-3.3 MDC Die Full production N/A N/A Samples tray of N/A - LP2951A MDC Die Full production N/A N/A Samples tray of N/A - LP2951A-3.3 MDC Die Full production N/A N/A Samples tray of N/A - Wafer Full production N/A wafer jar of N/A - Wafer Full production N/A wafer jar of N/A - Wafer Full production N/A wafer jar of N/A - LP2951A MWC LP2951A-3.3 MWC LP2951C MWC N/A N/A N/A file:///H|/imaging/BITTING/cpl/20020808_1/08062002_10/NATL/08062002_HTML/LP2951.html (4 of 6) [09-Aug-2002 9:39:38 AM] National P/N LP2951 - Series of Adjustable Micropower Voltage Regulators LP2951C-3.3 MWC Wafer Full production N/A wafer jar of N/A N/A General Description The LP2950 and LP2951 are micropower voltage regulators with very low quiescent current (75 A typ.) and very low dropout voltage (typ. 40 mV at light loads and 380 mV at 100 mA). They are ideally suited for use in battery-powered systems. Furthermore, the quiescent current of the LP2950/LP2951 increases only slightly in dropout, prolonging battery life. The LP2950-5.0 is available in the surface-mount D-Pak package, and in the popular 3-pin TO-92 package for pin-compatibility with older 5V regulators. The 8-lead LP2951 is available in plastic, ceramic dual-in-line, or metal can packages and offers additional system functions. One such feature is an error flag output which warns of a low output voltage, often due to falling batteries on the input. It may be used for a power-on reset. A second feature is the logic-compatible shutdown input which enables the regulator to be switched on and off. Also, the part may be pin-strapped for a 5V, 3V, or 3.3V output (depending on the version), or programmed from 1.24V to 29V with an external pair of resistors. Careful design of the LP2950/LP2951 has minimized all contributions to the error budget. This includes a tight initial tolerance (.5% typ.), extremely good load and line regulation (.05% typ.) and a very low output voltage temperature coefficient, making the part useful as a low-power voltage reference. Features 5V, 3V, and 3.3V versions available High accuracy output voltage Guaranteed 100 mA output current Extremely low quiescent current Low dropout voltage Extremely tight load and line regulation Very low temperature coefficient Use as Regulator or Reference Needs minimum capacitance for stability Current and Thermal Limiting Stable with low-ESR output capacitors Application Notes Title Size in Kbytes Date AN-853: Power Fail CircuitWorking with NS32FX200 67 Kbytes 5-Aug-95 View Online Download Receive via Email AN-908: Specification for the DECT ARi Interface to the Radio Frequency Front End 143 Kbytes 5-Aug-95 View Online Download Receive via Email 5-Aug-95 View Online Download Receive via Email AN-893: Using External Oscillators for the DP857X Real Time Clocks 73 Kbytes with the Battery Backed Mode Selection View Online Download Receive via Email file:///H|/imaging/BITTING/cpl/20020808_1/08062002_10/NATL/08062002_HTML/LP2951.html (5 of 6) [09-Aug-2002 9:39:38 AM] - National P/N LP2951 - Series of Adjustable Micropower Voltage Regulators If you have trouble printing or viewing PDF file(s), see Printing Problems. [Information as of 5-Aug-2002] Search Design Purchasing Quality Company Home About Languages . Website Guide . About "Cookies" . National is QS 9000 Certified . Privacy/Security Statement . Contact Us . Site Terms & Conditions of Use . Copyright 2002 (c) National Semiconductor Corporation . My Preferences . Feedback file:///H|/imaging/BITTING/cpl/20020808_1/08062002_10/NATL/08062002_HTML/LP2951.html (6 of 6) [09-Aug-2002 9:39:38 AM]