CM2838
300mA L
OW
E
SR
CMOS LDO W
ITH
E
NABLE
GENERAL DESCRIPTION
The CM2838 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 limit 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 CM2838 is stable with a Low ESR output capacitance of
1.0μF or greater.
FEATURES
Very Low Dropout Voltage
Low Current Consumption: Typ. 30μA, Max. 35μA
Output Voltage: 1.8V, 2.5V, 2.8V, 3.0V, and 3.3V
High Accuracy Output Voltage: +/- 1.5%
Guaranteed 300mA Output
Input Range up to 7.0V
Thermal Shutdown
Current Limiting
Stability with Low ESR Capacitors
Compact Package: SOT-23-5
Factory Pre-set Output Voltages
Low Temperature Coefficient
APPLICATIONS
Battery-powered devices
Personal communication devices
Home electric/electronic appliances
PC peripherals
TYPICAL APPLICATIONS
IN
IN
CM2838
BYP
GND
OUT
EN
OUT
5V
C1
1uF
C2
1nF
C3
1.0uF
2006/10/11
Rev. 1.3
Champion Microelectronic Corporation
Page 1
CM2838
300mA L
OW
E
SR
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
AMP
R2
GND
2006/10/11
Rev. 1.3
Champion Microelectronic Corporation
Page 2
CM2838
300mA L
OW
E
SR
CMOS LDO W
ITH
E
NABLE
ORDERING INFORMATION
Part Number
CM2838DIM25
CM2838KIM25
CM2838NIM25
CM2838PIM25
CM2838SIM25
CM2838GDIM25
CM2838GKIM25
CM2838GNIM25
CM2838GPIM25
CM2838GSIM25
Output Voltage
1.8V
2.5V
2.8V
3.0V
3.3V
1.8V
2.5V
2.8V
3.0V
3.3V
Temperature Range
-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
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
OPERATING RATINGS
Ambient Temperature Range (T
A
) ……... -40℃ to +85℃
Junction Temperature Range
…..…... -40℃ to +150℃
ESD Classification ………………………………………… B
THERMAL INFORMATION
Parameter
Maximum
Thermal Resistance (Θ
jc
)
SOT-23-5
160
Internal Power Dissipation (P
D
)
SOT-23-5
250
(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
mW
℃
℃
2006/10/11
Rev. 1.3
Champion Microelectronic Corporation
Page 3
CM2838
300mA L
OW
E
SR
CMOS LDO W
ITH
E
NABLE
ELECTRICAL CHARACTERISTICS
T
A
= +25℃; unless otherwise noted
CM2838
Min.
Note 1
I
O
= 1mA to 300mA
I
O
= 300mA,
V
OUT
=V
O(NOM)
-1.5%,
1.2V<V
O(NOM)
≤
2.0V
2.0V<V
O(NOM)
≤
2.5V
2.5V<V
O(NOM)
300
300
450
30
30
-0.1
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
Note 1.
V
IN(MIN)
= V
OUT
+ V
DROPOUT
Parameter
Input Voltage
Output Voltage Accuracy
Dropout Voltage
Output Current
Current Limit
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
Q
I
GND
REG
LINE
REG
LOAD
OTS
OTH
TC
Test Conditions
Typ.
Max.
7
1.5
1300
400
300
Unit
V
%
mV
mA
mA
-1.5
V
OUT
> 1.2V
V
OUT
> 1.2V
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
35
50
0.1
1
μA
μA
%
%
℃
℃
ppm/℃
dB
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
2.0
2
0
3.0
0.1
3.0
V
IN
0.4
μVrms
μVrms
μA
μA
μA
V
V
dB
PSRR
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
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
2006/10/11
Rev. 1.3
Champion Microelectronic Corporation
Page 4
CM2838
300mA L
OW
E
SR
CMOS LDO W
ITH
E
NABLE
DETAILED DESCRIPTION
The CM2838 family of CMOS regulators contain a PMOS pass transistor, voltage reference, error amplifier, over-current
protection, thermal shutdown.
The P-channel pass transistor receives data from the error amplifier, over-current 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 CM2838 switches from voltage mode to current mode when the load exceeds the rated output current. This prevents
over-stress.
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 CM2838 is stable with a Low ESR output capacitor to ground of 1.0μF or greater. It can keep stable even with higher 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.
2006/10/11
Rev. 1.3
Champion Microelectronic Corporation
Page 5
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