LP2950.pdf

Samsung PS42B430PZW - Zasilacz BN44-00273B, zamiennik AOZ1300AI

Zastanów sie kol mirex jak wspomniane przez Ciebie np. (MAX1563) w obudowie - 4mm x 4mm Thin QFN lub SO-8 BEZ przeróbki "wpasuje" za AOZ1300AI ? Link_ datasheet MAX1562/MAX1562H/MAX1563 http://obrazki.elektroda.pl/4521662100_1416554148_thumb.jpg http://obrazki.elektroda.pl/2396388000_1416556231_thumb.jpg (':!:') Pozostaje zakup orginału Opcja US $0.96 / piece Shipping: US $1.05 / piece 5 pieces / lot Time delivery 39 days of work Link * nie ma na Ebay"u p.s Tam przed diodą Schottky czyli na pin. trafo (9/10) jest_bywało ok. 5.5V AC (':idea:') Te wszystkie , które podałem niestety maja jedna wadę > potrzebna cewka dla pracy tej przetwornicy DC-DC lub maja za mały Ioo (prąd na wyjściu) Można "pobawić sie " z LP2950 patrz datasheet w zał. (str.12.) lub IC stabilizatorem napięcia LOW Droop z pin.EN - np z TPS736xx family Imax.0.5A - LP3963/LP3966 Imax.3A Pytanie: Ile prądu pobiera TV w St-by na linii STD5V


LP2950/LP2951
Series of Adjustable Micropower Voltage Regulators
General Description
The LP2950 and LP2951 are micropower voltage regulators
with very low quiescent current (75 uA 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

January 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

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2

LP2950/LP2951

Ordering Information
Package

Output Voltage
3.0V

TO-92 (Z)

3.3V

Temperature
5.0V

(?C)
-40 & lt; TJ & lt; 125

LP2950ACZ-3.0

LP2950ACZ-3.3

LP2950ACZ-5.0

LP2950CZ-3.0

LP2950CZ-3.3

LP2950CZ-5.0
LP2950CDT-5.0

-40 & lt; TJ & lt; 125

LP2951ACN-3.0

LP2951ACN-3.3

LP2951ACN

-40 & lt; TJ & lt; 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

TO-252 (D-Pak)
N (N-08E)
M (M08A)
MM (MUA08A)
J (J08A)

-40 & lt; TJ & lt; 125
-40 & lt; TJ & lt; 125

LP2951CMM
LP2951ACJ

-40 & lt; TJ & lt; 125

LP2951CJ
LP2951J

-55 & lt; TJ & lt; 150

LP2951J/883
5926-3870501MPA
H (H08C)

LP2951H/883

-55 & lt; TJ & lt; 150

5962-3870501MGA
WG (WG10A)

LP2951WG/883

-55 & lt; TJ & lt; 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

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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, 260?C
10 seconds, 240?C
75 seconds, 219?C
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
+150?C
-65? to +150?C

30V

-55? to +150?C
-40? to +125?C

Electrical Characteristics (Note 2)
LP2951
Parameter

Conditions
(Note 2)

LP2950AC-XX

Tested
Typ

Limit

LP2950C-XX

LP2951AC-XX

LP2951C-XX

Tested

(Notes 3, 16)

Design

Limit

Limit

(Note 3)

Typ

Tested

(Note 4)

Design

Limit

Limit

(Note 3)

Typ

Units

(Note 4)

3V VERSIONS (Note 17)
Output Voltage

TJ = 25?C

3.0

3.015

3.0

2.985
-25?C <= TJ <= 85?C

3.0

Full Operating

3.0

3.015

3.0

2.985
3.0

3.030

3.030

Temperature Range
Output Voltage

100 uA <= 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 = 25?C

3.3

3.317

3.3

3.284
-25?C <= TJ <= 85?C

3.3

Full Operating

3.3

3.317

3.3

3.284
3.3

3.333

3.333

Temperature Range
Output Voltage

100 uA <= 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 = 25?C

5.0

5.025

5.0

4.975
-25?C <= TJ <= 85?C

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 uA <= 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 uA <= IL <= 100 mA

0.04

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20

120

20

0.1

0.03

100
0.1

0.5

50
0.04

0.1

0.04

0.3

0.1

4

0.4
0.1

0.2

% max

0.2

0.2

% max
% max

0.2
0.3

% max

(Continued)
LP2951

Parameter

Conditions
(Note 2)

LP2950AC-XX

Tested
Typ

Limit

LP2950C-XX

LP2951AC-XX

LP2951C-XX

Tested

(Notes 3, 16)

Design

Limit

Limit

(Note 3)

Typ

Tested

(Note 4)

Design

Limit

Limit

(Note 3)

Typ

Units

(Note 4)

ALL VOLTAGE OPTIONS
Dropout Voltage
(Note 5)

IL = 100 uA

80
50

IL = 100 mA
IL = 100 uA

75

Current

80

50

450
380

Ground

80

150

150

75

600
120

8

12

8

Dropout

Vin = (VONOM - 0.5)V
IL = 100 uA

Current Limit

Vout = 0

110

110

12

14

160

170

220

110

200

160

220
0.05

mA max

12

mA max

170

uA max

200

mA max

220

0.2

uA max

uA max

200

200

mA max

200

8

200
160

uA max

120

14

170

mV max

mV max

140

14
Ground Current

600

380
75

140
IL = 100 mA

mV max

450

380

120

150

140

450

600

mV max

50

0.2

0.05

%/W max

Thermal Regulation

(Note 13)

0.05

Output Noise,

CL = 1 uF (5V Only)

430

430

430

0.2

uV rms

10 Hz to 100 kHz

CL = 200 uF

160

160

160

uV rms

100

100

100

uV rms

CL = 3.3 uF
(Bypass = 0.01 uF
Pins 7 to 1 (LP2951))
8-PIN VERSIONS ONLY

LP2951

Reference

1.235

Voltage

LP2951AC-XX

1.25

1.235

LP2951C-XX

1.25

1.26

1.235

1.26

1.26

1.22

V max
1.27

1.22

V max

1.21

V min

1.2
Reference

20

Bias Current
Reference Voltage

V min

1.27

1.285

V max

1.19

Feedback Pin

1.2

1.27

(Note 7)

Voltage

1.2
1.19

1.185

40

20

40

60
(Note 12)

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
IOL = 400 uA

Upper Threshold

(Note 6)

150

1

60

250

150

250

(Note 6)

75

40

60

95

75

95

15

15

mV min

140

75
140

mV max

25

60

uA max

400

150

40

uA max
2

mV max

250

mV max

40

25

140
(Note 6)

1

400

25

Voltage

0.01
2

400

Voltage

Hysteresis

0.01

2

Voltage

Lower Threshold

1

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

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LP2950/LP2951

Electrical Characteristics (Note 2)

LP2950/LP2951

Electrical Characteristics (Note 2)

(Continued)
LP2951

Parameter

Conditions
(Note 2)

LP2950AC-XX

Tested
Typ

Limit

LP2950C-XX

LP2951AC-XX

LP2951C-XX

Tested

(Notes 3, 16)

Design

Limit

Limit

(Note 3)

Typ

Tested

(Note 4)

Design

Limit

Limit

(Note 3)

Typ

Units

(Note 4)

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

10

3

10

3
20

uA max

750

450

uA max

20

uA max

600

750

20

uA max
100

uA max

10

uA 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 uA and CL = 1 uF for 5V versions and 2.2 uF 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 = 25?C. 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 uA <= IL <= 100 mA, TJ <= TJMAX.
Note 8: The junction-to-ambient thermal resistances are as follows: 180?C/W and 160?C/W for the TO-92 package with 0.40 inch and 0.25 inch leads to the printed
circuit board (PCB) respectively, 105?C/W for the molded plastic DIP (N), 130?C/W for the ceramic DIP (J), 160?C/W for the molded plastic SOP (M), 200?C/W for the
molded plastic MSOP (MM), and 160?C/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 20?C/W. Junction-to-case thermal resistance for the TO-252 package is
5.4?C/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 150?C for IL = 1 mA. For IL = 100 uA and TJ = 125?C, 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

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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

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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

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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

DS008546-53

DS008546-52

Line Regulation

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

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LP2950/LP2951

Application Hints
EXTERNAL CAPACITORS

sistor, note that while the output is rated to sink 400 uA, this
sink current adds to battery drain in a low battery condition.
Suggested values range from 100k to 1 MOhm. The resistor is
not required if this output is unused.

A 1.0 uF (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 uF 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 -30?C, so solid tantalums are recommended for operation below -25?C. The important parameters of the capacitor are an ESR of about 5 Ohm 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 uF for currents below 10 mA or 0.1 uF 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 uF (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 uA is recommended.
A 1 uF 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 uF 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 kOhm
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 uA forces an upper
limit of 1.2 MOhm 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 uA. Since
the LP2951 typically draws 60 uA 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 uF to 220 uF only decreases the noise from
430 uV to 160 uV 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 uF. When doing this, the output capacitor must
be increased to 3.3 uF to maintain stability. These changes
reduce the output noise from 430 uV to 100 uV 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

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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

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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

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LP2950/LP2951

Typical Applications

(Continued)
2 Ampere Low Dropout Regulator

DS008546-13

For 5Vout, use internal resistors. Wire pin 6 to 7, &amp; 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

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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

&amp; lt; 5.5V and turns on again at 6.0V. Current drain in disconnected mode is ? 150 uA.

15

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LP2950/LP2951

Typical Applications

(Continued)
System Overtemperature Protection Circuit

DS008546-18

LM34 for 125?F Shutdown
LM35 for 125?C Shutdown

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16

DS008546-23

17

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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

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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

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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

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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-5.0
NS Package Number TD03B

21

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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
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Europe
Fax: +49 (0) 1 80-530 85 86
Email: europe.support@nsc.com
Deutsch Tel: +49 (0) 1 80-530 85 85
English Tel: +49 (0) 1 80-532 78 32
Français Tel: +49 (0) 1 80-532 93 58
Italiano Tel: +49 (0) 1 80-534 16 80

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: sea.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.


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