MIC2950/2951
Micrel
3
February 1999
3-49
MIC2950/2951
150mA Low-Dropout Voltage Regulator
Block Diagram
60mV
1.23V
REF.
Error
Amp.
Error Detection
Comparator
182k
60k
1.5F
SNS
TAP
ERR
GND
OUT
5V/150mA
Output
TTL/CMOS
Compatible
Error Output
IN
FB
Unregulated
DC Supply
TTL/CMOS
Control Logic
Input
SHDN
330k
MIC2951-0x
General Description
The MIC2950 and MIC2951 are "bulletproof" micropower
voltage regulators with very low dropout voltage (typically
40mV at light loads and 250mV at 100mA), and very low
quiescent current. Like their predecessors, the LP2950 and
LP2951, the quiescent current of the MIC2950/MIC2951
increases only slightly in dropout, thus prolonging battery life.
The MIC2950/MIC2951 are pin for pin compatible with the
LP2950/LP2951, but offer lower dropout, lower quiescent
current, reverse battery, and automotive load dump protection.
The key additional features and protection offered include
higher output current (150mA), positive transient protection
for up to 60V (load dump), and the ability to survive an
unregulated input voltage transient of 20V below ground
(reverse battery).
The plastic DIP and SOIC versions offer additional system
functions such as programmable output voltage and logic
controlled shutdown. The 3-pin TO-92 MIC2950 is pin-
compatible with the older 5V regulators.
These system functions also include an error flag output that
warns of a low output voltage, which is often due to failing
batteries on the input. This may also be used as a power-on
reset. A logic-compatible shutdown input is also available
which enables the regulator to be switched on and off. This
part may also be pin-strapped for a 5 V output, or programmed
from 1.24 V to 29 V with the use of two external resistors.
Features
High accuracy 3.3, 4.85, or 5V, guaranteed 150mA output
Extremely low quiescent current
Low-dropout voltage
Extremely tight load and line regulation
Very low temperature coefficient
Use as regulator or reference
Needs only 1.5
F for stability
Current and thermal limiting
Unregulated DC input can withstand 20V reverse battery
and +60V positive transients
Error flag warns of output dropout (MIC2951)
Logic-controlled electronic shutdown (MIC2951)
Output programmable from 1.24V to 29V (MIC2951)
Applications
Automotive Electronics
Battery Powered Equipment
Cellular Telephones
SMPS Post-Regulator
Voltage Reference
Avionics
High Efficiency Linear Power Supplies
MIC2950/2951
Micrel
3-50
February 1999
Pin Description
Pin #
Pin #
Pin Name
Pin Function
MIC2950
MIC2951
3
1
OUT
Regulated Output
2
SNS
Sense (Input): Output-voltage sensing end of internal voltage divider for
fixed 5V operation. Not used in adjustable configuration.
3
SHDN
Shutdown/Enable (Input): TTL compatible input. High = shutdown,
low or open = enable.
2
4
GND
Ground
5
ERR
Error Flag (Output): Active low, open-collector output (low = error,
floating = normal).
6
TAP
3.3V/4.85/5V Tap: Output of internal voltage divider when the regulator is
configured for fixed operation. Not used in adjustable configuration.
7
FB
Feedback (Input): 1.235V feedback from internal voltage divider's TAP (for
fixed operation) or external resistor network (adjustable configuration).
1
8
IN
Unregulated Supply Input
Pin Configuration
1
2
3
4
8
7
6
5
IN
FB
TAP
ERR
OUT
SNS
SHDN
GND
MIC2951-xx
DIP (N), SOIC (M), MM8TM (MM)
(Top View)
3
2
1
OUT
GND
IN
MIC2950-xx
TO-92 (Z)
(Bottom View)
Ordering Information
Part Number
Voltage
Accuracy Temperature Range*
Package
MIC2950-05BZ
5.0V
0.5%
40
C to +125
C
TO-92
MIC2950-06BZ
5.0V
1.0%
40
C to +125
C
TO-92
MIC2951-02BM
5.0V
0.5%
40
C to +125
C
8-pin SOIC
MIC2951-03BM
5.0V
1.0%
40
C to +125
C
8-pin SOIC
MIC2951-02BN
5.0V
0.5%
40
C to +125
C
8-pin plastic DIP
MIC2951-03BN
5.0V
1.0%
40
C to +125
C
8-pin plastic DIP
MIC2951-03BMM
5.0V
1.0%
40
C to +125
C
8-lead MM8TM
MIC2951-3.3BM
3.3V
1.0%
40
C to +125
C
8-pin SOIC
MIC2951-4.8BM
4.85V
1.0%
40
C to +125
C
8-pin SOIC
* junction temperature
The MIC2950 is available as either an -05 or -06 version. The
-05 and -06 versions are guaranteed for junction temperatures
from 40
C to +125
C; the -05 version has a tighter output and
reference voltage specification range over temperature. The
MIC2951 is available as an -02 or -03 version.
The MIC2950 and MIC2951 have a tight initial tolerance
(0.5% typical), a very low output voltage temperature coefficient
which allows use as a low-power voltage reference, and
extremely good load and line regulation (0.04% typical). This
greatly reduces the error in the overall circuit, and is the result
of careful design techniques and process control.
MIC2950/2951
Micrel
3
February 1999
3-51
Electrical Characteristics
V
IN
= 6V; I
L
= 100
A; C
L
= 1
F; T
J
= 25
C, bold values indicate 40
C
T
J
+125
C; Note 8; unless noted.
Parameter
Condition
Min
Typ
Max
Units
Output Voltage
MIC295x-02/-05 (
0.5%), T
J
= 25
C
4.975
5.000
5.025
V
MIC295x-03/-06 (
1%), T
J
= 25
C
4.950
5.000
5.050
V
MIC2951-3.3 (
1%), T
J
= 25
C
3.267
3.300
3.333
V
MIC2951-4.8 (
1%), T
J
= 25
C
4.802
4.850
4.899
V
Output Voltage
MIC295x-02/-05 (
0.5%), 25
C
T
J
+85
C
4.950
5.050
V
MIC295x-03/-06 (
1%), 25
C
T
J
+85
C
4.925
5.075
V
MIC2951-3.3 (
1%), 25
C
T
J
+85
C
3.251
3.350
V
MIC2951-4.8 (
1%), 25
C
T
J
+85
C
4.777
4.872
V
Output Voltage
MIC295x-02/-05 (
0.5%), 40
C to +125
C
4.940
5.060
V
Over Full Temperature Range
MIC295x-03/-06 (
1%), 40
C to +125
C
4.900
5.100
V
MIC2951-3.3 (
1%), 40
C to +125
C
3.234
3.366
V
MIC2951-4.8 (
1%), 40
C to +125
C
4.753
4.947
V
Output Voltage
MIC295x-02/-05 (
0.5%), 100
A
I
L
150mA, T
J
T
J(max)
4.930
5.070
V
Over Load Variation
MIC295x-03/-06 (
1%), 100
A
I
L
150mA, T
J
T
J(max)
4.880
5.120
V
MIC2951-3.3 (
1%), 100
A
I
L
150mA, T
J
T
J(max)
3.221
3.379
V
MIC2951-4.8 (
1%), 100
A
I
L
150mA, T
J
T
J(max)
4.733
4.967
V
Output Voltage
MIC295x-02/-05 (
0.5%), Note 9
20
100
ppm/
C
Temperature Coefficient
MIC295x-03/-06 (
1%), Note 9
50
150
ppm/
C
MIC2951-3.3 (
1%), Note 9
50
150
ppm/
C
MIC2951-4.8 (
1%), Note 9
50
150
ppm/
C
Line Regulation
MIC295x-02/-05 (
0.5%), Note 10, 11
0.03
0.10
%
0.20
%
MIC295x-03/-06 (
1%), Note 10, 11
0.04
0.20
%
0.40
%
MIC2951-3.3 (
1%), Note 10, 11
0.04
0.20
%
0.40
%
MIC2951-4.8 (
1%), Note 10, 11
0.04
0.20
%
0.40
%
Absolute Maximum Ratings
(Note 1)
Input Suppy Voltage (V
IN
) Note 5 ................. 20V to +60V
Feedback Input Voltage (V
FB
) Note 6, 7 ...... 1.5V to +26V
Shutdown Input Voltage (V
SHDN
) Note 6 ..... 0.3V to +30V
Power Dissipation (P
D
) Note 4 ................ Internally Limited
Storage Temperature .............................. 65
C to + 150
C
Lead Temperature (soldering, 5 sec.) ....................... 260
C
ESD, Note 3
Operating Ratings
(Note 2)
Input Supply Voltage (V
IN
) ........................... +2.0V to +30V
Junction Temperature (T
J
) ....................................... Note 4
MIC2950-05/MIC2950-06 ..................... 40
C to +125
C
MIC2951-02/MIC2950-03 ..................... 40
C to +125
C
MIC2950/2951
Micrel
3-52
February 1999
Parameter
Condition
Min
Typ
Max
Units
Load Regulation
MIC295x-02/-05 (
0.5%), 100
A
I
L
150mA, Note 10
0.04
0.10
%
0.20
%
MIC295x-03/-06 (
1%), 100
A
I
L
150mA, Note 10
0.10
0.20
%
0.30
%
MIC2951-3.3 (
1%), 100
A
I
L
150mA, Note 10
0.10
0.20
%
0.30
%
MIC2951-4.8 (
1%), 100
A
I
L
150mA, Note 10
0.10
0.20
%
0.30
%
Dropout Voltage
MIC295x-02/-03/-05/-06, I
L
= 100
A, Note 12
40
80
mV
140
mV
MIC295x-02/-03/-05/-06, I
L
= 100mA, Note 12
250
300
mV
MIC295x-02/-03/-05/-06, I
L
= 150mA, Note 12
300
450
mV
600
mV
MIC2951-3.3 (
1%), I
L
= 100
A, Note 12
40
80
mV
150
mV
MIC2951-3.3 (
1%), I
L
= 100mA, Note 12
250
350
mV
MIC2951-3.3 (
1%), I
L
= 150mA, Note 12
320
450
mV
600
mV
MIC2951-4.8 (
1%), I
L
= 100
A, Note 12
40
80
mV
140
mV
MIC2951-4.8 (
1%), I
L
= 100mA, Note 12
250
300
mV
MIC2951-4.8 (
1%), I
L
= 150mA, Note 12
300
450
mV
600
mV
Ground Current
MIC295x-02/-03/-05/-06, I
L
= 100
A
120
180
A
300
A
MIC295x-02/-03/-05/-06, I
L
= 100mA
1.7
2.5
mA
3.5
mA
MIC295x-02/-03/-05/-06, I
L
= 150mA
4
6
mA
8
mA
MIC2951-3.3 (
1%), I
L
= 100
A
100
180
A
300
A
MIC2951-3.3 (
1%), I
L
= 100mA
1.7
2.5
mA
MIC2951-3.3 (
1%), I
L
= 150mA
4
6
mA
10
mA
MIC2951-4.8 (
1%), I
L
= 100
A
120
180
A
300
A
MIC2951-4.8 (
1%), I
L
= 100mA
1.7
2.5
mA
3.5
mA
MIC2951-4.8 (
1%), I
L
= 150mA
4
6
mA
8
mA
Dropout Ground Current
MIC295x-02/-03/-05/-06 (
0.5%), V
IN
= 4.5V, I
L
= 100
A
280
350
A
400
A
MIC2951-3.3 (
1%), V
IN
= 3.0V, I
L
= 100
A
150
350
A
400
A
MIC2951-4.8 (
1%), V
IN
= 4.3V, I
L
= 100
A
280
350
A
400
A
MIC2950/2951
Micrel
3
February 1999
3-53
Parameter
Condition
Min
Typ
Max
Units
Current Limit
V
OUT
= 0V
300
400
mA
450
mA
Thermal Regulation
Note 13
0.05
0.20
%/W
Output Noise
10Hz to 100kHz, C
L
= 1.5
F
430
V
RMS
10Hz to 100kHz, C
L
= 200
F
160
V
RMS
10Hz to 100kHz, C
L
= 3.3
F,
100
V
RMS
0.01
F bypass Feedback to Output
Reference Voltage
MIC295x-02/-05 (
0.5%)
1.220
1.235
1.250
V
1.200
1.260
V
MIC295x-03/-06 (
1%)
1.210
1.235
1.260
V
1.200
1.270
V
MIC2951-3.3 (
1%)
1.210
1.235
1.260
V
1.200
1.270
V
MIC2951-4.8 (
1%)
1.210
1.235
1.260
V
1.200
1.270
V
Reference Voltage
MIC295x-02/-05 (
0.5%), Note 14
1.190
1.270
V
MIC295x-03/-06 (
1%), Note 14
1.185
1.285
V
MIC2951-3.3 (
1%), Note 14
1.185
1.285
V
MIC2951-4.8 (
1%), Note 14
1.185
1.285
V
Feedback Bias Current
20
40
nA
60
nA
Reference Voltage
MIC295x-02/-05 (
0.5%), Note 9
20
ppm/
C
Temperature Coefficient
MIC295x-03/-06 (
1%), Note 9
50
ppm/
C
MIC2951-3.3 (
1%), Note 9
50
ppm/
C
MIC2951-4.8 (
1%), Note 9
50
ppm/
C
Feedback Bias Current
0.1
nA/
C
Temperature Coefficient
Error Comparator (Flag)
V
OH
= 30V
0.01
1.00
A
Output Leakage Current
2.00
A
Error Comparator (Flag)
V
IN
= 4.5V, I
OL
= 200
A
150
250
mV
Output Low Voltage
400
mV
Error Comparator
Note 15
40
60
mV
Upper Threshold Voltage
25
mV
Error Comparator
Note 15
75
95
mV
Lower Threshold Voltage
140
mV
Error Comparator Hysteresis
Note 15
15
mV
PDF 
ZIP