150mA Low Dropout
Voltage Regulators
CORPORATION
CLM2950 / CLM2951
FEATURES
PRODUCT DESCRIPTION
Calogic’s CLM2950 and CLM2951 are low power voltage
regulators. These devices are an excellent choice for use in
battery-powered applications such as cordless telephones,
radio control systems, and portable computers. The CLM2950
and CLM2951 features very low quiescent current and very
low dropout voltage (Typ. 50mV at light load and 380mV at
100mA). This includes a tight initial tolerance of 0.5% typ.,
extremely good load and line regulation of 0.05% typ. and
very low output temperature coefficient, making the
CLM2950/CLM2951 useful as a low-power voltage reference.
Other key additional features of this device includes higher
output current (150mA), positive transient protection up to 60V
(Load dump), and the ability to survive an unregulated input
voltage transient of -20V below ground (reverse battery).
The error flag output feature is used as power-on reset for
warning of a low output voltage, due to falling voltage input of
batteries. Another feature is the logic-compatible shutdown
input which enables the regulator to be switched on and off.
The CLM2950 is offered in a 3-pin TO-92 package compatible
with other 5 volt regulators. The CLM2951 is also available in
8-pin plastic and SO-8.
The regulator output voltage may be pin-strapped for a 5V,
3.3V and 3.0 volts or programmed from 1.24 volt to 29 volts
with an external pair of resistors.
ORDERING INFORMATION
PART
CLM2950ACN-X
CLM2950CN-X
CLM2951ACP-X
CLM2951CP-X
CLM2951ACS-X
CLM2951CS-X
PACKAGE
TEMPERATURE RANGE
IND.
IND.
IND.
IND.
IND.
IND.
TO-92 (3-Pin)
TO-92 (3-Pin)
Plastic DIP (8-Pin)
Plastic DIP (8-Pin)
Plastic SOIC (8-Pin)
Plastic SOIC (8-Pin)
•
5V, 3.3V, and 3.0V Versions at 150mA Output
•
Very Low Quiescent Current
•
Low Dropout Voltage and Line Regulation
•
Extremely Tight Load
•
Very Low Temperature Coefficient
•
Needs Only 1µF for Stability
•
Current and Thermal Limiting
•
Unregulated DC Input can Withstand -20V Reverse
Battery and +60V Positive Transients
•
Similar Replacement for LP2950/LP2951 Sockets
•
•
•
CLM2951 Versions Only
Error Flag Warns of Output Dropout
Logic-Controlled Electronic Shutdown
Output Programmable from 1.24 to 29V
APPLICATIONS
•
Battery Powered Systems
•
Cordless Telephones
•
Radio Control Systems
•
Portable / Palm Top / Notebook Computers
•
Portable Consumer Equipment
•
Portable Instrumentation
•
Avionics
•
Automotive Electronics
•
SMPS Post-Regulator
•
Voltage Reference
X = 3.0V, 3.3V or 5.0V
PIN CONNECTIONS
8-PIN SURFACE MOUNT
OUTPUT
SENSE
SHUTDOWN
GROUND
1
2
CLM2951
3
4
TOP VIEW
6
5
5V OR 3.3V TAP
ERROR
8
7
INPUT
FEEDBACK
TO-92
1
2
3
1. OUTPUT
2. GROUND
3. INPUT
BOTTOM VIEW
1D-46
1D-47
CALOGIC CORPORATION,
237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CLM2950 / CLM2951
CORPORATION
ABSOLUTE MAXIMUM RATINGS
Power Dissipation . . . . . . . . . . . . . . . . . . . . . Internally Limited
Lead Temp. (Soldering, 5 Seconds) . . . . . . . . . . . . . . . 260
o
C
Storage Temperature Range . . . . . . . . . . . . . . . -65 to +150
o
C
Operating Junction Temperature Range
CLM2951 . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +150
o
C
CLM2950AC/CLM2950C
CLM2951AC/CLM2951C . . . . . . . . . . . . . . . . -40 to +125
o
C
Input Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . -20 to +60V
Feedback Input Voltage . . . . . . . . . . . . . . . . . . . . -1.5 to +30V
Shutdown Input Voltage. . . . . . . . . . . . . . . . . . . . -0.3 to +30V
Error Comparator Output . . . . . . . . . . . . . . . . . . . -0.3 to +30V
ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2KV Min
ELECTRICAL CHARACTERISTICS:
V
S
= 15V, T
A
= 25
o
C, unless otherwise specified.
PARAMETER
MIN
3V VERSIONS
2.985
Output Voltage
2.964
Output Voltage
3.3V VERSIONS
3.284
Output Voltage
3.260
Output Voltage
5V VERSIONS
4.975
Output Voltage
4.94
Output Voltage
ALL VOLTAGE OPTIONS
Output Voltage
Temperature Coefficient
Line Regulation (Note 3)
Load Regulation (Note 3)
Dropout Voltage
(Note 5)
Ground Current
Current Limit
Thermal Regulation
Output Noise,
10Hz to 100KHz
8-PIN VERSIONS ONLY
Reference Voltage
Reference Voltage
Feedback Pin Bias Current
Reference Voltage
Temperature Coefficient
Feedback Pin Bias Current
Temperature Coefficient
1.22
1.19
40
20
0.1
20
0.03
0.04
50
380
450
150
3
5
130
0.05
430
160
100
CLM2951
1.235
1.25
1.27
60
120
0.1
0.1
80
450
500
170
6
8
200
0.2
20
0.03
0.04
50
380
450
150
3
5
130
0.05
430
160
100
CLM2951AC
1.22
1.19
40
20
0.1
1.235
1.25
1.27
60
0.1
0.1
80
450
500
170
6
8
200
0.2
50
0.04
0.1
50
380
450
150
3
5
130
0.05
0430
160
100
CLM2951C
1.21
1.18
40
50
0.1
1.23
1.26
1.28
60
V
V
nA
ppm/
o
C
nA/
o
C
(Note 7)
Over Temperature (Note 6)
0.2
0.2
80
450
500
170
6
8
200
0.2
ppm/
o
C
%
%
mV
mV
mV
µA
mA
mA
mA
%/W
µVrms
µVrms
µVrms
C
L
= 1µF
C
L
= 200µF
C
L
= 13.3µF
(Bypass = 0.01µF pins 7 to 1 (CLM2951))
CLM2951
TYP
3.0
MAX
3.015
3.036
3.0
3.3
3.045
3.317
3.340
3.3
5.0
3.350
5.025
5.06
5.0
5.075
CLM2950AC
CLM2951AC
MIN
2.985
2.970
2.964
2.958
3.284
3.267
3.260
3.254
4.975
4.95
4.94
4.93
TYP
3.0
3.0
3.0
3.0
3.3
3.3
3.3
3.3
5.0
5.0
5.0
5.0
MAX
3.015
3.030
3.036
3.042
3.317
3.333
3.340
3.346
5.025
5.050
5.06
5.07
CLM2950C
CLM2951C
MIN
2.970
2.955
2.940
2.928
3.267
3.251
3.234
3.221
4.95
4.925
4.90
4.88
TYP
3.0
3.0
3.0
3.0
3.3
3.3
3.3
3.3
5.0
5.0
5.0
5.0
MAX
3.030
3.045
3.060
3.072
3.333
3.350
3.366
3.379
5.05
5.075
5.10
5.12
UNITS
CONDITIONS
(Note 2)
V
V
V
V
V
V
V
V
V
V
V
V
T
J
= 25
o
C
-25
o
C
≤
T
J
≤
85
o
C
Full Operating Temperature
100µA
≤
I
L
≤
150mA,T
J
≤T
JMAX
T
J
= 25
o
C
-25
o
C
≤
T
J
≤
85
o
C
Full Operating Temperature
100µA
≤
I
L
≤
150mA, T
J
≤T
JMAX
T
J
= 25
o
C
-25
o
C
≤
T
J
≤
85
o
C
Full Operating Temperature
100µA
≤
I
L
≤
150mA, T
J
≤
T
JMAX
2.955
3.251
4.925
(Note 1)
6V
≤
V
IN
≤
30V (Note 4)
100µA
≤
IL
≤
150mA
I
L
= 100µA
I
L
= 100mA
I
L
= 150mA
I
L
= 100µA
I
L
= 100mA
I
L
= 150mA
V
OUT
= 0
CALOGIC CORPORATION,
237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CLM2950 / CLM2951
CORPORATION
ELECTRICAL CHARACTERISTICS
(continued)
PARAMETER
MIN
ERROR COMPARATOR
Output Leakage Current
Output Low Voltage
Upper Threshold Voltage
Lower Threshold Voltage
Hysteresis
SHUTDOWN INPUT
Input Logic Voltage
Shutdown Pin
Input Current
Regulator Output Current
In Shutdown
CLM2951
TYP
0.01
150
60
75
15
1.3
2
30
675
3
50
800
10
MAX
1
250
40
95
CLM2950AC
CLM2951AC
MIN
TYP
MAX
0.01
150
60
75
15
1.3
2
30
675
3
50
800
10
1
250
40
95
CLM2950C
CLM2951C
MIN
TYP MAX
0.01
150
60
75
15
1.3
2
30
675
3
50
800
10
1
250
95
UNITS
CONDITIONS
(Note 2)
40
µA
mV
mV
mV
mV
V
V
µA
µA
µA
V
oh
= 30V
V
IN
= 4.5V, I
OL
= 400µA
(Note 8)
(Note 8)
(Note 8)
Low (Regulator ON)
High (Regulator OFF)
V
S
= 2.4V
V
S
= 30V
(Note 9)
0.6
0.7
0.7
Note 1:
Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range.
Note 2:
Unless otherwise specified all limits guaranteed for T
J
= 25
o
C, V
IN
= 6V, I
L
= 100µA and C
L
= 1µF. Additional conditions for the 8-pin
versions are feedback tied to 5V tap and output tied to output Sense (V
OUT
= 5V) and V
SHUTDOWN
≤
0.8V.
Note 3:
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 4:
Line regulation for the CLM2951 is tested at 150
o
C for I
L
= 1mA. For I
L
= 100µA and T
J
= 125
o
C, line regulation is guaranteed by design
to 0.2%. See typical performance characteristics for line regulation versus temperature and load current.
Note 5:
Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV 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 input account.
Note 6:
V
REF
≤
V
OUT
≤
(V
IN
- 1V), 2.3
≤
V
IN
≤
30V, 100µA
≤
I
L
≤
150mA, T
J
≤
T
JMAX
.
Note 7:
Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temprtature range.
Note 8:
Comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below the nominal reference voltage
measured at 6V input. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = V
OUT
/V
REF
=
(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 95mV x
5V/1.235 = 384mV. Thresholds remain constant as a percent of V
OUT
as V
OUT
is varied, with the dropout warning occurring at typically 5% below
nominal, 7.5% guaranteed.
Note 9:
V
SHUTDOWN
≥
2V, V
IN
≤
30V, V
OUT
= 0, Feedback pin tied to 5V Tap.
Note 10:
All typical values are not guaranteed.
BLOCK DIAGRAM
UNREGULATED DC
7
FEEDBACK
8
INPUT
1
OUTPUT
2
SENSE
+
3
FROM
CMOS
OR TTL
SHUTDOWN
+
60mV
+
1.23V
REFERENCE
GROUND
CLM2950 AND CLM2951 BLOCK DIAGRAM
1D-48
+
5V @ 150mA
MAX
–
ERROR
AMPLIFIER
180k
Ω
6
5V TAP
330k
Ω
+
1µF
TO CMOS OR
TTL
60kΩ
+
–
ERROR DETECTION
COMPARATOR
5
ERROR
4
CALOGIC CORPORATION,
237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CLM2950 / CLM2951
CORPORATION
APPLICATION HINTS
EXTERNAL CAPACITORS
•
The stability of the CLM2950/CLM2951 requires a 1.0µF or
greater capacitor between output and ground. Oscillation
could occur without this capacitor. Most types of tantalum
or aluminum electrolytic works fine here. For operations
below -25
o
C a solid tantalum is recommended since the
many aluminum types have electrolytes that freeze at about
-30
o
C. The ESR of about 5Ω or less and resonant
frequency about 500kHz are the most important parameters
in the value of the capacitor. The capacitors value can be
increased without limit.
The error comparator has an open-collector output which
requires an external pull-up resistor. Depending on the
system requirements the resistor may be returned to 5V
output or other supply voltage. In determining the value of
this resistor, note that the output is rated to sink 400µA, this
value adds to battery drain in a low battery condition.
Suggested values range from 100K to 1MΩ. If the output is
unused this resistor is not required.
PROGRAMMING THE OUTPUT VOLTAGE OF CLM2951
The CLM2951 may be pin-strapped for 5V using its internal
voltage divider by tying Pin 1 (output) to Pin 2 (sense) and Pin
7 (feedback) to Pin 6 (5V Tap). Also, 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.
Refer to the below equation for the programming of the output
voltage:
V
OUT
= V
REF
×
(1 + R
1
\R
2
) + I
FB
R
1
The V
REF
is 1.235 and I
FB
is the feedback bias current,
nominally -20nA. The minimum recommended load current of
1µA forces an upper limit of 1.2MΩ on value of R
2
. If no load
is presented the I
FB
produces an error of typically 2% in V
OUT
which may be eliminated at room temperature by trimming R
1
.
To improve the accuracy choose the value of R2 = 100k this
reduces the error by 0.17% and increases the resistor
program current by 12µA. Since the CLM2951 typically draws
60µA at no load with Pin 2 open-circuited this is a small price
to pay.
REDUCING OUTPUT NOISE
It may be an advantage to reduce the AC noise present at the
output. One way is to reduce the regulator bandwidth by
increasing the size of the output capacitor. This is the only
way that noise can be reduced on CLM2950 but is relatively
inefficient, as increasing the capacitor from 1µF to 220µF only
decreases the noise from 430µV to 160µVrms for a 100kHz
bandwidth at 5V output.
Noise could also be reduced fourfold by a bypass capacitor
across R
1
, since it reduces the high frequency gain from 4 to
unity.
C
BYPASS
≅
1/2πR
1
×
200Hz
or choose 0.01µF. When doing this, the output capacitor must
be increased to 3.3µF to maintain stability. These changes
reduce the output noise from 430µV to 100µVrms for a
100kHz bandwidth at 5V output. With the bypass capacitor
added, noise no longer scales with output voltage so that
improvements are more dramatic at higher voltages.
•
At lower values of output current, less output capacitance is
required for stability. For currents below 10mA the value of
the capacitor can be reduced to 0.5µF and 0.15µF for 1mA.
More output capacitance is needed for the 8-pin version at
voltages below 5V since it runs the error amplifier at lower
gain.
•
At worst case 5µF or greater must be used for the condition
of 150mA load at 1.23V output.
•
The
CLM2950, unlike other low dropout regulators, will
remain stable and in regulation with no load in addition to
the internal voltage divider. The feature is especially
important in applications like CMOS RAM keep-alive
circuits. When setting the output voltage of the CLM2951
version with external resistors, a minimum load of 1µA is
recommended.
•
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
then a 1µA tantalum or aluminum electrolytic capacitor
should be placed from the input to the ground.
can occur if there is a stray capacitance to the
CLM2951 feedback terminal (pin 7). This could cause more
problems when using a higher value of external resistors to
set the output voltage. This problem can be fixed by adding
a 100pF capacitor between output and feedback and
increasing the output capacitor to at least 3.3µF.
•
Instability
ERROR DETECTION COMPARATOR OUTPUT
The Comparator produces a logic low output whenever the
CLM2951 output falls out of regulation by more than around
5%. This is around 60mV offset divided by the 1.235
reference voltage. This trip level remains 5% below normal
regardless of the programmed output voltage of the regulator.
Figure 1 shows the timing diagram depicting the ERROR
signal and the regulator output voltage as the CLM2951 input
is ramped up and down. The ERROR signal becomes low at
around 1.3V input, and goes high around 5V input (input
voltage at which V
OUT
= 4.75). Since the CLM2951’s dropout
voltage is load dependent, the input voltage trip point (around
5V) will vary with the load current. The output voltage trip
point (approx. 4.75V) does not vary with load.
CALOGIC CORPORATION,
237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CLM2950 / CLM2951
CORPORATION
TYPICAL PERFORMANCE CHARACTERISTICS
SHUTDOWN THRESHOLD VOLTAGE (V)
1.8
1.6
1.4
1.2
1.0
0.8
SHUTDOWN
THRESHOLD VOLTAGE
OUTPUT VOLTAGE CHANGE (mV)
OUTPUT CURRENT (mA)
30
25
20
15
10 T
J
= 150˚C
5
0
LINE REGULATION
I
L
= 100µA
I
L
= 1mA
180
160
140
120
100
80
60
40
20
0
0
RATED
OUTPUT CURRENT
8-PIN SOIC
SOLDERED
TO PC BOARD
T
JMAX
= 125˚C
V
OUT
= 5V
T
A
= 25˚C
T
A
= 50˚C
T
A
= 85˚C
5
10
15
20
25
INPUT VOLTAGE (V)
30
1E-01
0.6
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (˚C)
1D-49
10
I
L
= 100µA
5 T
J
= 125˚C
0
–5
–10
25
30
5
10
15
20
INPUT VOLTAGE (V)
1D-50
125
OUTPUT VOLTAGE
CHANGE (mV)
100
75
50
25
0
–25
–50
100mA
100µA
0
LOAD TRANSIENT
RESPONSE
OUTPUT VOLTAGE
CHANGE (mV)
80
60
40
20
0
–20
–40
–60
100mA
100µA
0
LOAD TRANSIENT
RESPONSE
OUTPUT
VOLTAGE (V)
7
6
5
4
3
2
ENABLE TRANSIENT
C
L
= 1.5µF
I
L
= 10mA
V
IN
= 8V
C
L
= 10µF
V
OUT
= 5V
LOAD CURRENT
LOAD CURRENT
C
L
= 4.7µF
V
OUT
= 5V
C
L
= 15µF
V
OUT
= 5V
SHUTDOWN
PIN VOLTAGE (V)
1
0
2
0
–2
–100 0
2
4
6
TIME (mS)
8
10
1E-02
4
8
12
TIME (mS)
16
20
1E-03
100 200 300 400 500 600 700
TIME (µs)
1E-04
8
COMPARATOR OUTPUT (V)
ERROR
COMPARATOR OUTPUT
V
OUT
= 5V
SINK CURRENT (mA)
2.5
COMPARATOR
SINK CURRENT
T
A
= 125˚C
400mV
OUTPUT VOLTAGE
CHANGE
200mV
0
LINE TRANSIENT
RESPONSE
6
2.0
4
HYSTERESIS
2
1.5
T
A
= 25˚C
–50mV
8V
6V
4V
0
200
400
C
L
= 4.7µF
I
L
= 1mA
V
OUT
= 5V
1.0
T
A
= –55˚C
0.5
0
NOTE: PULLUP RESISTOR
TO SEPARATE 5V SUPPLY
–2
0
1
2
3
4
5
INPUT VOLTAGE (V)
6
1E-05
0.0
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
1E-06
INPUT
VOLTAGE
600
800
1E-07
CALOGIC CORPORATION,
237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
Embedded System
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