LM2931
SERIES
VERY LOW DROP VOLTAGE
REGULATOR WITH INHIBIT FUNCTION
December 1999
BLOCK DIAGRAM
s
VERY LOW DROPOUT VOLTAGE (0.15V
TYP. AT 10mA LOAD)
s
LOW QUIESCENT CURRENT (TYP 2.5mA,
AT 100mA LOAD)
s
OUTPUT CURRENT UP TO 100mA
s
ADJUSTABLE (FROM V
OUT
=2.5V ONLY
SO-8) AND FIXED (3.3V & 5V) OUTPUT
VOLTAGE VERSION
s
INTERNAL CURRENT AND THERMAL LIMIT
s
LOAD DUMP PROTECTION UP TO 60V
s
REVERSE TRANSIENT PROTECTION UP TO
-50V
s
TEMPERATURE RANGE: -40 TO 125
o
C
s
PACKAGE AVAILABLE: TO-92, DPAK,
TO-220, SO-8 (WITH INHIBIT CONTROL)
DESCRIPTION
The
LM2931
series
are
very
low
drop
regulators. The very low drop voltage and the
low quiescent current make them particular
suitable for low noise, low power applications
and in battery powered systems. In the 8 pin
configation (SO-8), fully compatible to the older
L78L0 0 family, a shut down Logic Control
function is available.
This means that when the device is used as a
local regulator is possible to put a part of the
board in stand-by decreasing the total power
consumption. Ideal for automotive application
the LM2931 is proteceted from reverse battery
installations or 2 battery jumps. During the
transient, suchs as a a load dump (60V) when
the input voltage can exceed the specified
maximum operating input voltage (26V), the
regulator will automatically shut down to protect
both internal circuit and the load.
TO-252 (DPAK)
TO-220
SO-8
TO-92
1/16
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
IN
DC Positive Input Voltage
40
V
V
IN
DC Reverse Input Voltage
-15
V
V
IN
Transient Input Voltage (
< 100ms)
60
V
V
IN
Transient Reverse Input Voltage (
< 100ms)
-50
V
V
I NH
Inhibit Input Voltage
40
V
I
O UT
Output Current
Int ernally Limit ed
mA
T
stg
Storage Temperature Range
-65 to 150
o
C
T
o p
Operating Junction Temperature Range
-40 to 125
o
C
Absolute Maximum Ratings are those value beyond which damage to the device may occur. Functional operation under these condition is
not implied.
CONNECTION DIAGRAM AND ORDERING NUMBERS (top view)
TO-220
DPAK (*)
TO-92 (*)
SO-8 (*)
Output Voltage
LM2931AV33
LM2931BV33
LM2931AV50
LM2931BV50
LM2931ADT33
LM2931BDT33
LM2931ADT50
LM2931BDT50
LM2931AZ33
LM2931BZ33
LM2931AZ50
LM2931BZ50
LM2931AD33
LM2931BD33
LM2931AD50
LM2931BD50
3.3V
3.3V
5V
5V
LM2931D
2.5V t o 26V
(*) Available in Tape & Reel with the suffix "R" for fixed version and "-R" for adjustable version.
TO-220
DPAK
SO-8
TO-92
pin 1 = OUT
pin 2 = GND
pin 3 = IN
BOTTOM VIEW
(*) = N.C. for FIXED and ADJ for ADJUSTABLE
LM2931 SERIES
2/16
APPLICATION CIRCUIT FOR FIXED OUTPUT (Figure 1)
APPLICATION CIRCUIT FOR ADJUSTABLE OUTPUT (Figure 2)
R
1
suggested Value = 27K
V
O
= V
REF
x
R
1
+
R
2
R
1
LM2931 SERIES
3/16
ELECTRICAL CHARACTERISTICS FOR LM2931A 3.3V (refer to the test circuits,
T
j
= 25
o
C, V
IN
= 14 V, C
IN
= 0.1
F, C
O
= 100
F, I
O
= 10mA, V
INH
= 0V unless otherwise specified)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
I
Maximum Operating Input
Voltage
I
O
= 10 mA
T
j
= -40 to 125
o
C
26
37
V
V
O
Output Voltage
3.175
3.3
3. 425
V
V
O
Output Voltage
I
O
= 100 mA
V
IN
= 6 to 26 V
T
j
= -40 to 125
o
C
3.135
3.3
3. 465
V
V
O
Line Regulation
V
IN
= 9 to 16 V
2
10
mV
V
O
Line Regulation
V
IN
= 6 to 26 V
4
33
mV
V
O
Load Regulation
I
O
= 5 to 100 mA
10
33
mV
V
d
Dropout Voltage (Note 1, 2)
I
O
= 10 mA
90
250
V
V
d
Dropout Voltage (Note 1, 2)
I
O
= 100 mA
250
600
V
I
d
Quiescent Current
ON Mode: I
OUT
= 100mA
2.5
30
mA
I
d
Quiescent Current
OFF Mode: V
INH
= 2.5 V R
LOAD
= 330
0.3
1
mA
I
SC
Short Circuit Current
100
300
mA
SVR
Supply Voltage Rejection
I
O
= 100 mA
V
IN
= 14
2V
f = 120 Hz
T
j
= -40 to 125
o
C
55
78
dB
V
I L
Control Input Voltage
T
j
= -40 to 125
o
C
2
1.2
V
V
IH
Control Input Voltage
T
j
= -40 to 125
o
C
3.25
2
V
I
INH
Inhibit Input Current
V
INH
= 2.5 V
22
50
A
V
IN
Transient Input Voltage
R
LOAD
= 330
< 100ms
60
70
V
V
IN
Reverse Polarity Input
Voltage
V
O
0.3V
R
LOAD
= 330
-15
-50
V
V
IN
Reverse Polarity Input
Voltage Transient
R
LOAD
= 330
< 100ms
-50
V
eN
Output Noise Voltage
B = 10Hz to 100KHz
330
V
RM S
Note 1: Reference Voltage is measured from V
OUT
to AJD pin.
Note 2: V
d
measured when the output voltage has dropped 100mV from the nominal value obtained at 14V.
LM2931 SERIES
4/16
ELECTRICAL CHARACTERISTICS FOR LM2931B 3.3V (refer to the test circuits,
T
j
= 25
o
C, V
IN
= 14 V, C
IN
= 0.1
F, C
O
= 100
F, I
O
= 10mA, V
INH
= 0V unless otherwise specified)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
V
I
Maximum Operating Input
Voltage
I
O
= 10 mA
T
j
= -40 to 125
o
C
26
37
V
V
O
Output Voltage
3.135
3.3
3. 465
V
V
O
Output Voltage
I
O
= 100 mA
V
IN
= 6 to 26 V
T
j
= -40 to 125
o
C
2.97
3.3
3.63
V
V
O
Line Regulation
V
IN
= 9 to 16 V
2
10
mV
V
O
Line Regulation
V
IN
= 6 to 26 V
4
33
mV
V
O
Load Regulation
I
O
= 5 to 100 mA
10
33
mV
V
d
Dropout Voltage (Note 1, 2)
I
O
= 10 mA
90
200
V
V
d
Dropout Voltage (Note 1, 2)
I
O
= 100 mA
250
600
V
I
d
Quiescent Current
ON Mode: I
OUT
= 100mA
2.5
30
mA
I
d
Quiescent Current
OFF Mode: V
INH
= 2.5 V R
LOAD
= 330
0.3
1
mA
I
SC
Short Circuit Current
100
300
mA
SVR
Supply Voltage Rejection
I
O
= 100 mA
V
IN
= 14
2V
f = 120 Hz
T
j
= -40 to 125
o
C
55
78
dB
V
I L
Control Input Voltage
T
j
= -40 to 125
o
C
2
1.2
V
V
IH
Control Input Voltage
T
j
= -40 to 125
o
C
3.25
2
V
I
INH
Inhibit Input Current
V
INH
= 2.5 V
22
50
A
V
IN
Transient Input Voltage
R
LOAD
= 330
< 100ms
60
70
V
V
IN
Reverse Polarity Input
Voltage
V
O
0.3V
R
LOAD
= 330
-15
-50
V
V
IN
Reverse Polarity Input
Voltage Transient
R
LOAD
= 330
< 100ms
-50
V
eN
Output Noise Voltage
B = 10Hz to 100KHz
330
V
RM S
Note 1: Reference Voltage is measured from V
OUT
to AJD pin.
Note 2: V
d
measured when the output voltage has dropped 100mV from the nominal value obtained at 14V.
LM2931 SERIES
5/16
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