CM2831
300mA CMOS LDO W
ITH
E
NABLE
GENERAL DESCRIPTION
The CM2831 family is a positive voltage linear regulator
developed utilizing CMOS technology featured low quiescent
current (30µA typ.), low dropout voltage, and high output
voltage accuracy, making them ideal for battery applications.
EN input connected to CMOS has low bias current. The
space-saving SOT-23-5 package is attractive for “Pocket” and
“Hand Held” applications.
These rugged devices have both Thermal Shutdown, and
Current Fold-back to prevent device failure under the “Worst”
of operating conditions.
In application requiring a low noise, regulated supply, place a
1000pF capacitor between Bypass and Ground.
The CM2831 is stable with an output capacitance of 2.2µF or
greater.
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FEATURES
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Very Low Dropout Voltage
Low Current Consumption: Typ. 30µA, Max. 35µA
Output Voltage: 1.8V, 1.9V, 2.2V, 2.5V, 2.7V, 2.8V, 2.9V,
3.0V, 3.3V, 3.5V, 3.6V, and 3.8V
High Accuracy Output Voltage: +/- 1.5%
Guaranteed 300mA Output
Input Range up to 7.0V
Thermal Shutdown
Current Limiting
Compact Package: SOT-23-5
Factory Pre-set Output Voltages
Short Circuit Current Fold-Back
Low Temperature Coefficient
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APPLICATIONS
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Battery-powered devices
Personal communication devices
Home electric/electronic appliances
PC peripherals
24 Hours Technical Support--WebSIM
Champion provides customers an online circuit simulation tool
called WebSIM. You could simply logon our website at
www.champion-micro.com for details.
TYPICAL APPLICATIONS
IN
IN
C M 2831
BYP
GND
OUT
EN
OUT
5V
C1
1uF
C2
1nF
C3
2 .2 u F
2003/11/20
Rev. 1.5
Champion Microelectronic Corporation
Page 1
CM2831
300mA CMOS LDO W
ITH
E
NABLE
PIN CONFIGURATION
SOT-23-5
Top View
5
4
VOUT
GND
2
VIN
1
BLOCK DIAGRAM
IN
EN
3
BYP
OUT
1uA
Overcurrent
Shutdown
Thermal
Shutdown
EN
BYP
R1
-
+
Vref = 1.176V
AM P
R2
GND
2003/11/20
Rev. 1.5
Champion Microelectronic Corporation
Page 2
CM2831
300mA CMOS LDO W
ITH
E
NABLE
ORDERING INFORMATION
Part Number
CM2831DIM25
CM2831EIM25
CM2831HIM25
CM2831KIM25
CM2831MIM25
CM2831NIM25
CM2831OIM25
CM2831PIM25
CM2831SIM25
CM2831UIM25
CM2831VIM25
CM2831XIM25
Output Voltage
1.8V
1.9V
2.2V
2.5V
2.7V
2.8V
2.9V
3.0V
3.3V
3.5V
3.6V
3.8V
Temperature Range
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
-40℃ ~ +85℃
Package
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
Note: For other pre-set output voltage requirements, please contact Champion Sales office.
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Output Current
Output Voltage
…………….……………………………. +7V
…………………….……
P
D
/ (V
IN
- Vo) mA
…………………… GND-0.3V to V
IN
+0.3V
………………………………………… B
OPERATING RATINGS
Ambient Temperature Range (T
A
) ……... -40℃ to +85℃
Junction Temperature Range
…..…... -40℃ to +125℃
ESD Classification
THERMAL INFORMATION
Parameter
Maximum
Thermal Resistance (Θ
jc
)
SOT-23-5
160
Internal Power Dissipation (P
D
)
SOT-23-5
320
(ΔT = 100℃)
Maximum Junction Temperature
150
Maximum Lead Temperature (10 Sec)
300
Caution: Stress above the listed absolute rating may cause permanent damage to the device.
Unit
℃/W
℃/W
℃
℃
2003/11/20
Rev. 1.5
Champion Microelectronic Corporation
Page 3
CM2831
300mA CMOS LDO W
ITH
E
NABLE
ELECTRICAL CHARACTERISTICS
T
A
= +25℃; unless otherwise noted
CM2831
Min.
Note 1
I
O
= 1mA
I
O
= 300mA,
V
OUT
=V
O(NOM)
-2%,
1.2V<V
O(NOM)
<=2.0V
2.0V<V
O(NOM)
<=2.5V
2.5V<V
O(NOM)
300
300
450
150
30
30
0.02
0.2
150
30
40
I
O
= 100mA
C
O
=2.2µF ceramic
I
O
= 100mA
Power Supply Rejection
PSRR
C
O
=2.2µF ceramic
C
BYP
=0.01µF
Output Voltage Noise
Output Voltage Noise
Shutdown Supply Current
EN Input Bias Current
EN Input Threshold
eN
eN
I
SD
I
EH
I
EL
V
EH
V
EL
f=10Hz to 100kHz
I
O
= 10mA, C
BYP
=0µF
f=10Hz to 100kHz
I
O
= 10mA, C
BYP
=0.01µF
f=1kHz
f=10kHz
f=100kHz
f=1kHz
f=10kHz
f=100kHz
C
O
=2.2µF
C
O
=100µF
C
O
=2.2µF
C
O
=100µF
60
50
40
75
55
30
30
20
30
20
2.0
1.0
(Note2)
0
3.0
0.1
3.0
V
IN
0.4
μVrms
μVrms
μA
μA
μA
V
V
dB
dB
300
35
50
0.1
1
-1.5
Typ.
Max.
7
1.5
1300
800
300
Parameter
Input Voltage
Output Voltage Accuracy
Dropout Voltage
Output Current
Current Limit
Short Circuit Current
Quiescent Current
Ground Pin Current
Line Regulation
Load Regulation
Over Temperature Shutdown
Over Temperature Hysteresis
V
OUT
Temperature Coefficient
Power Supply Rejection
Symbol
V
IN
V
OUT
V
DROPOUT
I
O
I
LIM
I
SC
I
Q
I
GND
REG
LINE
REG
LOAD
OTS
OTH
TC
PSRR
Test Conditions
Unit
V
%
mV
mV
mA
mA
mA
μA
μA
%
%
℃
℃
ppm/℃
V
OUT
> 1.2V
V
OUT
> 1.2V
V
OUT
< 0.95V
I
O
= 0mA
I
O
= 1mA to 300mA
I
OUT
=5mA, V
IN
=V
OUT
+1 to V
OUT
+2
I
O
=1mA to 300mA
V
IN
=5.0V, V
OUT
=0V, V
EN
< V
EL
V
EN
=V
IN
, V
IN
=2.6V to 7V
V
EN
=0, V
IN
=2.6V to 7V
V
IN
=2.6V to 7V
V
IN
=2.6V to 7V
Note 1.
V
IN(MIN)
= V
OUT
+ V
DROPOUT
Note 2.
Based on our design architecture, the enable input threshold will depend on the input voltage. To ensure the stability of your design
application, please set the
V
EH (MIN)
= V
IN
/2 + 0.8V.
2003/11/20
Rev. 1.5
Champion Microelectronic Corporation
Page 4
CM2831
300mA CMOS LDO W
ITH
E
NABLE
DETAILED DESCRIPTION
The CM2831 family of CMOS regulators contain a PMOS pass transistor, voltage reference, error amplifier, over-current
protection, thermal shutdown, and short circuit protection.
The P-channel pass transistor receives data from the error amplifier, over-current shutdown, short output protection, and thermal
protection circuits. During normal operation, the error amplifier compares the output voltage to a precision reference. Over-current
and Thermal shutdown circuits become active when the junction temperature exceeds 150℃, or the current exceeds 300mA.
During thermal shutdown, the output voltage remains low. Normal operation is restored when the junction temperature drops
below 120℃.
The CM2831 switches from voltage mode to current mode when the load exceeds the rated output current. This prevents
over-stress. The CM2831 also incorporates current fold-back to reduce power dissipation when the output is short-circuited. This
feature becomes active when the output drops below 1.05V, and reduces the current flow by 65%. Full current is restored when
the voltage exceeds 0.95V.
ENABLE
The Enable pin normally floats high. When actively, pulled low, the PMOS pass transistor shut off, and all internal circuits are
powered down. In this state, the quiescent current is less than 2µA. This pin behaves much like an electronic switch.
EXTERNAL CAPACITOR
The CM2831 is stable with an output capacitor to ground of 2.2µF or greater. It can keep stable even with higher or poor ESR
capacitors. A second capacitor is recommended between the input and ground to stabilize VIN. The input capacitor should be
larger than 0.1µF to have a beneficial effect. All capacitors should be placed in close proximity to the pins. A “quiet” ground
termination is desirable.
2003/11/20
Rev. 1.5
Champion Microelectronic Corporation
Page 5
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