NSC LM2931Z-5.0, LM2931T-5.0, LM2931S-5.0, LM2931M-5.0, LM2931CT Datasheet

LM2931
Series Low Dropout Regulators

General Description

The LM2931 positive voltage regulator features a very low
quiescent current of 1mA or less when supplying 10mA
loads. This unique characteristic and the extremely low
input-output differential required for proper regulation (0.2V
for output currents of 10mA) make the LM2931 the ideal
regulator for standby power systems. Applications include
memory standby circuits, CMOS and other low power pro­cessor power supplies as well as systems demanding as
much as 100mA of output current.

Designed originally for automotive applications, the LM2931
and all regulated circuitry are protected from reverse battery
installations or 2 battery jumps. During line transients, such
as a load dump (60V) when the input voltage to the regulator
can momentarily exceed the specified maximum operating
voltage, the regulator will automatically shut down to protect
both internal circuits and the load. The LM2931 cannot be
harmed by temporary mirror-image insertion. Familiar regu­lator features such as short circuit and thermal overload pro­tection are also provided.

The LM2931 family includes a fixed 5V output (

±

3.8% toler-

ance for A grade) or an adjustable output with ON/OFF pin.

Both versions are available in a TO-220 power package,
TO-263 surface mount package, and an 8-lead surface
mount package. The fixed output version is also available in
the TO-92 plastic and 6-Bump micro SMD packages.

Features

n Very low quiescent current
n Output current in excess of 100 mA
n Input-output differential less than 0.6V
n Reverse battery protection
n 60V load dump protection
n −50V reverse transient protection
n Short circuit protection
n Internal thermal overload protection
n Mirror-image insertion protection
n Available in TO-220, TO-92, TO-263, SO-8 or 6-Bump

micro SMD packages

n Available as adjustable with TTL compatible switch
n See AN-1112 for micro SMD considerations

Connection Diagrams

FIXED VOLTAGE OUTPUT

TO-220 3-Lead Power Package

DS005254-6

Front View

TO-263 Surface-Mount Package

DS005254-11

Top View

DS005254-12

Side View

8-Pin Surface Mount

DS005254-7

*NC = Not internally connected. Must be electrically isolated from the rest
of the circuit for the micro SMD package.

Top View

TO-92 Plastic Package

DS005254-8

Bottom View

March 2000

LM2931Series Low Dropout Regulators

© 2000 National Semiconductor Corporation DS005254 www.national.com

Connection Diagrams (Continued)

ADJUSTABLE OUTPUT VOLTAGE

6-Bump micro SMD

DS005254-38

Top View

(Bump Side Down)

micro SMD Laser Mark

DS005254-39

TO-220 5-Lead Power Package

DS005254-9

Front View

TO-263

5-Lead Surface-Mount Package

DS005254-13

Top View

DS005254-14

Side View

8-Pin Surface Mount

DS005254-10

Top View

LM2931

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Connection Diagrams (Continued)
Ordering Information

Output

Number

Package Part Number Package Marking Transport Media NSC

Drawing

5V 3-Pin TO-220 LM2931T-5.0 LM2931T-5.0 Rails T03B

LM2931AT-5.0 LM2931AT-5.0 Rails

3-Pin TO-263 LM2931S-5.0 LM2931S-5.0 Rails TS3B

LM2931AS-5.0 LM2931AS-5.0 Rails

TO-92 LM2931Z-5.0 LM2931Z-5 1.8k Units per Box Z03A

LM2931AZ-5.0 LM2931AZ 1.8k Units per Box

8-Pin
SOIC

LM2931M-5.0 2931M-5.0 Rails M08A

LM2931AM-5.0 2931AM-5.0 Rails

*

6-Bump

micro SMD

LM2931IBPX-5.0 - Tape and Reel BPA06HTA

Adjustable,
3V to 24V

5-Pin TO-220 LM2931CT LM2931CT Rails T05A
5-Pin TO-263 LM2931CS LM2931CS Rails TS5B
8-Pin

SOIC

LM2931CM LM2931CM Rails M08A

3.3V

*

6-Bump

micro SMD

LM2931IBPX-3.3 - Tape and Reel BPA06HTA

Note: The micro SMD package marking is a single digit manufacturing Date Code Only.

LM2931

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Typical Applications

LM2931 Fixed Output

DS005254-4

*

Required if regulator is located far from power supply filter.

*

*C2 must be at least 100 µF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to the
regulator. This capacitor must be rated over the same operating temperature range as the regulator. The equivalent series resistance (ESR) of this capacitor is
critical; see curve.

LM2931 Adjustable Output

DS005254-5

Note: Using 27k for R1 will automatically compensate for errors in V

OUT

due to the input bias current of the ADJ pin (approximately 1 µA).

LM2931

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Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Input Voltage

Operating Range 26V
Overvoltage Protection

LM2931A, LM2931C (Adjustable) 60V
LM2931 50V

Internal Power Dissipation

(Note 2) (Note 4) Internally Limited

Operating Ambient Temperature

Range −40˚C to +85˚C
Maximum Junction Temperature 125˚C
Storage Temperature Range −65˚C to +150˚C
Lead Temp. (Soldering, 10 seconds) 230˚C
ESD Tolerance (Note 5) 2000V

Electrical Characteristics for Fixed 3.3V Version

VIN= 14V, IO= 10mA, TJ= 25˚C, C2= 100µF (unless otherwise specified) (Note 2)

Parameter Conditions LM2931-3.3 Units

Typ Limit

(Note 3)

Output Voltage 3.3 3.465

3.135

V

MAX

V

MIN

4V ≤ VIN≤ 26V, IO= 100 mA

−40˚C ≤ T

J

≤ 125˚C

3.630

2.970

V

MAX

V

MIN

Line Regulation 4V ≤ VIN≤ 26V 4 33 mV

MAX

Load Regulation 5mA ≤ IO≤ 100mA 10 50 mV

MAX

Output Impedance 100mADCand 10mA

rms

,

100Hz - 10kHz

200 mΩ

Quiescent Current I

O

≤ 10mA, 4V ≤ VIN≤ 26V 0.4 1.0 mA

MAX

−40˚C ≤ TJ≤ 125˚C
I

O

= 100mA, VIN= 14V, TJ= 25˚C 15 mA

Output Noise Voltage 10Hz -100kHz, C

OUT

= 100µF 330 µV

rms

Long Term Stability 13 mV/1000 hr
Ripple Rejection f

O

= 120Hz 80 dB

Dropout Voltage I

O

= 10mA

I

O

= 100mA

0.05

0.30

0.2

0.6

V

MAX

Maximum Operational
Input Voltage

33 26 V

MIN

Maximum Line Transient RL= 500Ω,VO≤5.5V,

T = 1ms, τ≤100ms

70 50 V

MIN

Reverse Polarity Input
Voltage, DC

VO≥ −0.3V, RL= 500Ω −30 −15 V

MIN

Reverse Polarity Input
Voltage, Transient

T = 1ms, τ≤100ms, RL= 500Ω −80 −50 V

MIN

Electrical Characteristics for Fixed 5V Version

VIN= 14V, IO= 10mA, TJ= 25˚C, C2 = 100 µF (unless otherwise specified) (Note 2)

Parameter Conditions LM2931A-5.0 LM2931-5.0 Units

Typ

Limit

(Note 3)

Typ

Limit

(Note 3)

Output Voltage 5 5.19

4.81

5 5.25

4.75

V

MAX

V

MIN

6.0V ≤ VIN≤ 26V, IO= 100mA

−40˚C ≤ T

J

≤ 125˚C

5.25

4.75

5.5

4.5

V

MAX

V

MIN

Line Regulation 9V ≤ VIN≤ 16V

6V ≤ V

IN

≤ 26V

2
4

10
30

2
4

10
30

mV

MAX

Load Regulation 5 mA ≤ IO≤ 100mA 14 50 14 50 mV

MAX

Output Impedance 100mADCand 10mA

rms

,

100Hz -10kHz

200 200 mΩ

LM2931

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Electrical Characteristics for Fixed 5V Version (Continued)

VIN= 14V, IO= 10mA, TJ= 25˚C, C2 = 100 µF (unless otherwise specified) (Note 2)

Parameter Conditions LM2931A-5.0 LM2931-5.0 Units

Typ

Limit

(Note 3)

Typ

Limit

(Note 3)

Quiescent Current I

O

≤ 10mA, 6V ≤ VIN≤ 26V 0.4 1.0 0.4 1.0 mA

MAX

−40˚C ≤ TJ≤ 125˚C
I

O

= 100mA, VIN= 14V, TJ= 25˚C 15 30

5

15 mA

MAX

mA

MIN

Output Noise Voltage 10Hz -100kHz, C

OUT

= 100µF 500 500 µV

rms

Long Term Stability 20 20 mV/1000

hr

Ripple Rejection f

O

= 120 Hz 80 55 80 dB

MIN

Dropout Voltage IO= 10mA

I

O

= 100mA

0.05

0.3

0.2

0.6

0.05

0.3

0.2

0.6

V

MAX

Maximum Operational Input
Voltage

33 26 33 26 V

MIN

Maximum Line Transient RL= 500Ω,VO≤5.5V,

T = 1ms, τ≤100ms

70 60 70 50 V

MIN

Reverse Polarity Input
Voltage, DC

VO≥ −0.3V, RL= 500Ω −30 −15 −30 −15 V

MIN

Reverse Polarity Input
Voltage, Transient

T = 1ms, τ≤100ms, RL= 500Ω −80 −50 −80 −50 V

MIN

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Electrical specifications do not apply when operating the device
beyond its rated operating conditions.

Note 2: See circuit in Typical Applications. To ensure constant junction temperature, low duty cycle pulse testing is used.
Note 3: All limits are guaranteed for T

J

= 25˚C (standard type face) or over the full operating junction temperature range of −40˚C to +125˚C (bold type face).

Note 4: The maximum power dissipation is a function of maximum junction temperatureT

Jmax

, total thermal resistance θJA, and ambient temperature TA. The maxi-

mum allowable power dissipation at any ambient temperature is P

D

=(T

Jmax−TA

)/θJA. If this dissipation is exceeded, the die temperature will rise above150˚Cand

the LM2931 will gointothermalshutdown. For the LM2931 in the TO-92 package, θ

JA

is 195˚C/W; in the SO-8 package, θJAis 160˚C/W, and in the TO-220 package,

θ

JA

is 50˚C/W; in the TO-263 package, θJAis 73˚C/W; and in the 6-Bump micro SMD package θJAis 290˚C/W. If the TO-220 package is used with a heat sink, θ

JA

is the sum of the package thermal resistance junction-to-case of 3˚C/W and the thermal resistance added by the heat sink and thermal interface.
If the TO-263 package is used, the thermal resistance can be reduced by increasing the P.C. board copper area thermally connected to the package: Using 0.5 square

inches of copper area, θ

JA

is 50˚C/W; with 1 square inch of copper area, θJAis 37˚C/W; and with 1.6 or more square inches of copper area, θJAis 32˚C/W.

Note 5: Human body model, 100 pF discharged through 1.5 kΩ.

Electrical Characteristics for Adjustable Version

VIN= 14V, V

OUT

= 3V, IO= 10 mA, TJ= 25˚C, R1 = 27k, C2 = 100 µF (unless otherwise specified) (Note 2)

Parameter Conditions Typ Limit Units

Limit

Reference Voltage 1.20 1.26 V

MAX

1.14 V

MIN

IO≤ 100 mA, −40˚C ≤ Tj≤ 125˚C, R1 = 27k 1.32 V

MAX

Measured from V

OUT

to Adjust Pin 1.08 V

MIN

Output Voltage Range 24 V

MAX

3V

MIN

Line Regulation V

OUT

+ 0.6V ≤ VIN≤ 26V 0.2 1.5 mV/V

MAX

Load Regulation 5 mA ≤ IO≤ 100 mA 0.3 1 %

MAX

Output Impedance 100 mADCand 10 mA

rms

, 100 Hz–10 kHz 40 mΩ/V

Quiescent Current I

O

= 10 mA 0.4 1 mA

MAX

IO= 100 mA 15 mA
During Shutdown R

L

= 500Ω 0.8 1 mA

MAX

Output Noise Voltage 10 Hz–100 kHz 100 µV

rms

/V
Long Term Stability 0.4 %/1000 hr
Ripple Rejection f

O

= 120 Hz 0.02 %/V

LM2931

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