Linear Voltage Regulator IC


Manufacturer Part NumberLP2951CM
DescriptionLinear Voltage Regulator IC
ManufacturerNational Semiconductor
LP2951CM datasheet

Specifications of LP2951CM

Dropout Voltage Vdo380mVNo. Of Pins8
Output Current0.1AMounting TypeSurface Mount
Voltage Regulator TypeLDO LinearPeak Reflow Compatible (260 C)No
Output Voltage5VOutput Voltage Max29V
TopologyLDORegulator Output TypeAdjustable
Polarity TypePositiveNumber Of OutputsSingle
Input Voltage (max)30VPackage TypeSOIC N
Load Regulation0.1%Line Regulation0.1%
Output Voltage Accuracy±0.5%Operating Temp Range-40C to 125C
Operating Temperature ClassificationAutomotivePin Count8
MountingSurface MountLead Free Status / RoHS StatusContains lead / RoHS non-compliant
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Series of Adjustable Micropower Voltage Regulators
General Description
The LP2950 and LP2951 are micropower voltage regulators
with very low quiescent current (75μA typ.) and very low
dropout voltage (typ. 40mV at light loads and 380mV at
100mA). 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
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, LLP, 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 re-
Careful design of the LP2950/LP2951 has minimized all con-
tributions to the error budget. This includes a tight initial
tolerance (.5% typ.), extremely good load and line regulation
Block Diagram and Typical Applications
© 2010 National Semiconductor Corporation
(.05% typ.) and a very low output voltage temperature coef-
ficient, making the part useful as a low-power voltage refer-
5V, 3V, and 3.3V versions available
High accuracy output voltage
Guaranteed 100mA 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 (10mΩ to 6Ω)
LP2951 versions only
Error flag warns of output dropout
Logic-controlled electronic shutdown
Output programmable from 1.24 to 29V
November 8, 2010

LP2951CM Summary of contents

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    ... This includes a tight initial tolerance (.5% typ.), extremely good load and line regulation Block Diagram and Typical Applications © 2010 National Semiconductor Corporation LP2950/LP2951 (.05% typ.) and a very low output voltage temperature coef- ficient, making the part useful as a low-power voltage refer- ence ...

  • Page 2

    Connection Diagrams TO-92 Plastic Package (Z) Bottom View Dual-In-Line Packages (N, J) Surface-Mount Package (M, MM) Top View Metal Can Package (H) Top View LP2951 10-Lead Ceramic Surface-Mount Package (WG) 854602 854626 Connect DAP to GND at device pin ...

  • Page 3

    ... LP2951ACMX LP2951CM 2951CM* (where * is die rev letter) LP2951CMX LP2951ACMM-3.0 L0BA LP2951CMM-3.0 L0BB LP2951CMMX-3.0 LP2951ACMM-3.3 L0CA LP2951CMM-3.3 L0CB LP2951CMMX-3.3 LP2951ACMM L0DA LP2951ACMMX LP2951CMM L0DB LP2951CMMX LP2951J/883 See MIL/AERO Datasheet LP2951H/883 See MIL/AERO Datasheet LP2951WG/883 See MIL/AERO Datasheet ...

  • Page 4

    Temperature Package V OUT Range 8-lead LLP −40 < T < 125 3.0 J 3.3 5.0 Part Package Number Marking LP2951ACSD-3.0 51AC30 LP2951ACSDX-3.0 LP2951CSD-3.0 51AC30B LP2951CSDX-3.0 LP2951ACSD-3.3 51AC33 LP2951ACSDX-3.3 LP2951CSD-3.3 51AC33B LP2951CSDX-3.3 LP2951ACSD 2951AC LP2951ACSDX LP2951CSD 2951ACB LP2951CSDX 4 ...

  • Page 5

    ... Absolute Maximum Ratings 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 (T ...

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    Conditions Parameter (Note All Voltage Options Output Voltage (Note 12) Temperature Coefficient Line Regulation (V NOM + 1)V O (Note 14) ≤ 30V (Note ≤ ≤ 100μA Load Regulation I L (Note 14) = 100μA Dropout Voltage I L (Note ...

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    Conditions Parameter (Note 2) Error Comparator Output Leakage V = 30V OH Current Output Low NOM − 0. 400μA Voltage I OL Upper Threshold (Note 6) Voltage Lower Threshold (Note 6) Voltage Hysteresis ...

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    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 may also be procured as Standard Military Drawing Spec ...

  • Page 9

    Output Voltage vs. Temperature of 3 Representative Units 854631 Quiescent Current 854633 Quiescent Current 854635 Quiescent Current Quiescent Current Short Circuit Current 9 854632 854634 854636 ...

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    Dropout Voltage LP2951 Minimum Operating Voltage LP2951 Feedback Pin Current Dropout Voltage 854637 LP2951 Feedback Bias Current 854639 LP2951 Error Comparator Output 854641 10 854638 854640 854642 ...

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    LP2951 Comparator Sink Current 854643 Load Transient Response 854645 LP2951 Enable Transient 854647 Line Transient Response Load Transient Response Output Impedance 11 854644 854646 854648 ...

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    Ripple Rejection Ripple Rejection LP2951 Divider Resistance Ripple Rejection 854649 LP2951 Output Noise 854651 Shutdown Threshold Voltage 854653 12 854650 854652 854654 ...

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    Line Regulation LP2950 Maximum Rated Output Current Output Capacitor ESR Range LP2951 Maximum Rated Output Current 854655 Thermal Response 854657 854663 13 854656 854658 ...

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    Application Hints EXTERNAL CAPACITORS A 1.0μF (or greater) capacitor is required between the output and ground for stability at output voltages more. At lower output voltages, more capacitance is required (2.2μF or more is recommended for 3V ...

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    Application Hints **Drive with TTL-high to shut down. Ground or leave open if shutdown fea- ture is not to be used. Note: Pins 2 and 6 are left open. FIGURE 2. Adjustable Regulator REDUCING OUTPUT NOISE In reference applications ...

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    Typical Applications 300mA Regulator with 0.75V Dropout Low Drift Current Source 1A Regulator with 1.2V Dropout Wide Input Voltage Range Current Limiter 854621 *Minimum input-output voltage ranges from 40mV to 400mV, depending on load current. Current limit is typically ...

  • Page 17

    Regulator with Early Warning and Auxiliary Output ■ Early warning flag on low input voltage ■ Main output latches off at lower input voltages ■ Battery backup on auxiliary output ■ Operation: Reg. #1 programmed one diode drop ...

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    Regulator with 2.5V Sleep Function *High input lowers V to 2.5V out *Optional Latch off when drop out occurs. Adjust R3 for C2 Switching when V **Outputs go low when V drops below designated thresholds. in Open Circuit ...

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    For values shown, Regulator shuts down when V *Sets disconnect Voltage **Sets disconnect Hysteresis LM34 for 125°F Shutdown LM35 for 125°C Shutdown Low Battery Disconnect < 5.5V and turns on again at 6.0V. Current drain in disconnected mode is in ...

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    Schematic Diagram 20 ...

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    Physical Dimensions inches (millimeters) unless otherwise noted Order Number LP2951WG/883 NS Package Number WG10A Metal Can Package (H) NS Package Number H08C 21 ...

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    Ceramic Dual-In-Line Package (J) NS Package Number J08A Surface Mount Package (M) NS Package Number M08A 22 ...

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    Molded Dual-In-Line Package (N) NS Package Number N08E Molded TO-92 Package (Z) NS Package Number Z03A 23 ...

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    Surface Mount Package (MM) NS Package Number MUA08A D-Pak Package NS Package Number TD03B 24 ...

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    LLP Package NS Package Number SDC08A 25 ...

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    ... For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Amplifiers Audio Clock and Timing Data Converters Interface LVDS Power Management Switching Regulators LDOs LED Lighting www ...