DMOS
100mA Low-Dropout Regulator
FEATURES
q
NEW DMOS TOPOLOGY:
Ultra Low Dropout Voltage:
60mV typ at 100mA
Output capacitor NOT required for stability
q
FAST TRANSIENT RESPONSE
q
VERY LOW NOISE: 23
Vrms
q
HIGH ACCURACY:
1.5% max
q
HIGH EFFICIENCY:
I
GND
= 500
A at I
OUT
= 100mA
Not Enabled: I
GND
= 10nA
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2.5V, 2.8V, 2.85V, 3.0V, 3.3V, 5.0V, AND
ADJUSTABLE OUTPUT VERSIONS
q
OTHER OUTPUT VOLTAGES AVAILABLE UPON
REQUEST
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FOLDBACK CURRENT LIMIT
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THERMAL PROTECTION
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SMALL SURFACE-MOUNT PACKAGES:
SOT23-5 and SO-8
APPLICATIONS
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PORTABLE COMMUNICATION DEVICES
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BATTERY-POWERED EQUIPMENT
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PERSONAL DIGITAL ASSISTANTS
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MODEMS
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BAR-CODE SCANNERS
q
BACKUP POWER SUPPLIES
DESCRIPTION
The REG101 is a family of low-noise, low-dropout linear
regulators with low ground pin current. Its new DMOS
topology provides significant improvement over previous
designs, including low dropout voltage (only 60mV typ at
full load), and better transient performance. In addition, no
output capacitor is required for stability, unlike conventional
low-dropout regulators that are difficult to compensate and
require expensive low ESR capacitors greater than 1
F.
Typical ground pin current is only 500
A (at I
OUT
= 100mA)
and drops to 10nA when not in enabled mode. Unlike regula-
tors with PNP pass devices, quiescent current remains rela-
tively constant over load variation and under dropout condi-
tions.
The REG101 has very low output noise (typically 23
Vrms
for V
OUT
= 3.3V with C
NR
= 0.01
F), making it ideal for use
in portable communications equipment. Accuracy is main-
tained over temperature, line, and load variations. Key
parameters are tested over the specified temperature range
(40
C to +85
C).
The REG101 is well protected--internal circuitry provides a
current limit that protects the load from damage. Thermal
protection circuitry keeps the chip from being damaged by
excessive temperature. The REG101 is available in the
SOT23-5 and the SO-8 packages.
REG101
(Fixed Voltage
Versions)
Enable
Gnd
0.1
F
C
OUT
(1)
+
+
V
OUT
V
IN
NR
NR = Noise Reduction
NOTE: (1) Optional.
REG101-A
Gnd
Enable
0.1
F
+
C
OUT
(1)
+
V
OUT
V
IN
R
2
R
1
Adj
REG1
01
REG101
SBVS026C JULY 2001
www.ti.com
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright 2000, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
REG101
2
SBVS026C
ABSOLUTE MAXIMUM RATINGS
(1)
Supply Input Voltage, V
IN
...................................................... 0.3V to 12V
Enable Input ............................................................................ 0.3V to V
IN
Output Short-Circuit Duration ...................................................... Indefinite
Operating Temperature Range (T
J
) ................................ 55
C to +125
C
Storage Temperature Range (T
A
) ................................... 65
C to +150
C
Lead Temperature (soldering, 3s, SOT23-5, and SO-8) ..................... +240
C
NOTE: (1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods may degrade
device reliability.
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Texas Instru-
ments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.
ESD damage can range from subtle performance degrada-
tion to complete device failure. Precision integrated circuits
may be more susceptible to damage because very small
parametric changes could cause the device not to meet its
published specifications.
5V Output
REG101NA-5
SOT23-5
331
R01B
REG101NA-5/250
Tape and Reel
"
"
"
"
REG101NA-5/3K
Tape and Reel
REG101UA-5
SO-8
182
REG101U50
REG101UA-5
Rails
"
"
"
"
REG101UA-5/2K5
Tape and Reel
3.3V Output
REG101NA-3.3
SOT23-5
331
R01C
REG101NA-3.3/250
Tape and Reel
"
"
"
"
REG101NA-3.3/3K
Tape and Reel
REG101UA-3.3
SO-8
182
REG101U33
REG101UA-3.3
Rails
"
"
"
"
REG101UA-3.3/2K5
Tape and Reel
3V Output
REG101NA-3
SOT23-5
331
R01D
REG101NA-3/250
Tape and Reel
"
"
"
"
REG101NA-3/3K
Tape and Reel
REG101UA-3
SO-8
182
REG101U30
REG101UA-3
Rails
"
"
"
"
REG101UA-3/2K5
Tape and Reel
2.85V Output
REG101NA-2.85
SOT23-5
331
R01N
REG101NA-2.85/250
Tape and Reel
"
"
"
"
REG101NA-2.85/3K
Tape and Reel
REG101UA-2.85
SO-8
182
REG101285
REG101UA-2.85
Rails
"
"
"
"
REG101UA-2.85/2K5
Tape and Reel
2.8V Output
REG101NA-2.8
SOT23-5
331
R01E
REG101NA-2.8/250
Tape and Reel
"
"
"
"
REG101NA-2.8/3K
Tape and Reel
REG101UA-2.8
SO-8
182
REG101U28
REG101UA-2.8
Rails
"
"
"
"
REG101UA-2.8/2K5
Tape and Reel
2.5V Output
REG101NA-2.5
SOT23-5
331
R01G
REG101NA-2.5/250
Tape and Reel
"
"
"
"
REG101NA-2.5/3K
Tape and Reel
REG101UA-2.5
SO-8
182
REG101U25
REG101UA-2.5
Rails
"
"
"
"
REG101UA-2.5/2K5
Tape and Reel
Adjustable Output
REG101NA-A
SOT23-5
331
R01A
REG101NA-A/250
Tape and Reel
"
"
"
"
REG101NA-A/3K
Tape and Reel
REG101UA-A
SO-8
182
REG101UA
REG101UA-A
Rails
"
"
"
"
REG101UA-A/2K5
Tape and Reel
PACKAGE/ORDERING INFORMATION
NOTE: (1) Models with a slash (/) are available only in Tape and Reel in the quantities indicated (e.g., /2K5 indicates 2500 devices per reel). Ordering 2500 pieces
of "REG101UA-5/2K5" will get a single 2500-piece Tape and Reel.
Many custom output voltage versions, from 2.5V to 5.1V in 50mV increments, are available upon request. Minimum order
quantities apply. Contact factory for details.
PACKAGE
DRAWING
PACKAGE
ORDERING
TRANSPORT
PRODUCT
PACKAGE
NUMBER
MARKING
NUMBER
(1)
MEDIA
REG101
3
SBVS026C
ELECTRICAL CHARACTERISTICS
Boldface limits apply over the specified temperature range, T
J
= 40
C to +85
C.
At T
J
= +25
C, V
IN
= V
OUT
+ 1V (V
OUT
= 2.5V for REG101-A), V
ENABLE
= 1.8V, I
OUT
= 2mA, C
NR
= 0.01
F, and C
OUT
= 0.1
F
(1)
, unless otherwise noted.
REG101NA
REG101UA
PARAMETER
CONDITION
MIN
TYP
MAX
UNITS
OUTPUT VOLTAGE
Output Voltage
V
OUT
REG101-2.5
2.5
V
REG101-2.8
2.8
V
REG101-2.85
2.85
V
REG101-3.0
3.0
V
REG101-3.3
3.3
V
REG101-5
5
V
REG101-A
2.5
5.5
V
Reference Voltage
V
REF
1.267
V
Adjust Pin Current
I
ADJ
0.2
1
A
Accuracy
0.5
1.5
%
Over Temperature
2.2
%
vs Temperature
dV
OUT
/dT
50
ppm/
C
Includes Line and Load
I
OUT
= 2mA to 100mA, V
IN
= (V
OUT
+ 0.4V) to 10V
0.8
2.0
%
Over Temperature
V
IN
= (V
OUT
+ 0.6V) to 10V
2.7
%
DC DROPOUT VOLTAGE
(2)
V
DROP
I
OUT
= 2mA
4
10
mV
For all models
I
OUT
= 100mA
60
100
mV
Over Temperature
I
OUT
= 100mA
130
mV
VOLTAGE NOISE
V
n
f = 10Hz to 100kHz
Without C
NR
C
NR
= 0, C
OUT
= 0
23
Vrms/V V
OUT
Vrms
With C
NR
(all fixed voltage models)
C
NR
= 0.01
F, C
OUT
= 10
F
7
Vrms/V V
OUT
Vrms
OUTPUT CURRENT
Current Limit
(3)
I
CL
130
170
220
mA
Over Temperature
110
240
mA
Short-Circuit Current
I
SC
60
mA
RIPPLE REJECTION
f = 120Hz
I
OUT
= 100mA
65
dB
ENABLE CONTROL
V
ENABLE
High (output enabled)
V
ENABLE
1.8
V
IN
V
V
ENABLE
Low (output disabled)
0.2
0.5
V
I
ENABLE
High (output enabled)
I
ENABLE
V
ENABLE
= 1.8V to V
IN
, V
IN
= 1.8V to 6.5
(4)
1
100
nA
I
ENABLE
Low (output disabled)
V
ENABLE
= 0V to 0.5V
2
100
nA
Output Disable Time
C
OUT
= 1.0
F, R
LOAD
= 33
200
s
Output Enable Time
C
OUT
= 1.0
F, R
LOAD
= 33
1.5
ms
THERMAL SHUTDOWN
Junction Temperature
Shutdown
160
C
Reset from Shutdown
140
C
GROUND PIN CURRENT
Ground Pin Current
I
GND
I
OUT
= 2mA
400
500
A
I
OUT
= 100mA
500
650
A
Enable Pin Low
V
ENABLE
0.5V
0.01
0.2
A
INPUT VOLTAGE
V
IN
Operating Input Voltage Range
(5)
1.8
10
V
Specified Input Voltage Range
V
IN
> 1.8V
V
OUT
+ 0.4
10
V
Over Temperature
V
IN
> 1.8V
V
OUT
+ 0.6
10
V
TEMPERATURE RANGE
Specified Range
T
J
40
+85
C
Operating Range
T
J
55
+125
C
Storage Range
T
A
65
+150
C
Thermal Resistance
SOT23-5 Surface Mount
JA
Junction-to-Ambient
200
C/W
SO-8 Surface Mount
JA
Junction-to-Ambient
150
C/W
NOTES: (1) The REG101 does not require a minimum output capacitor for stability. However, transient response can be improved with proper capacitor selection. (2) Dropout
voltage is defined as the input voltage minus the output voltage that produces a 2% change in the output voltage from the value at V
IN
= V
OUT
+ 1V at fixed load. (3) Current limit
is the output current that produces a 10% change in output voltage from V
IN
= V
OUT
+ 1V and I
OUT
= 2mA. (4) For V
ENABLE
> 6.5V, see typical characteristic "I
ENABLE
vs V
ENABLE
".
(5) The REG101 no longer regulates when V
IN
< V
OUT
+ V
DROP (MAX)
. In drop-out, the impedance from V
IN
to V
OUT
is typically less than 1
at T
J
= +25
C.
REG101
4
SBVS026C
PIN CONFIGURATIONS
Top View
V
OUT
(2)
V
OUT
(2)
NR/Adjust
(1)
GND
V
IN
(3)
V
IN
(3)
NC
Enable
SO-8
1
2
3
4
8
7
6
5
(U Package)
V
IN
GND
Enable
V
OUT
NR/Adjust
(1)
SOT23-5
1
2
3
5
4
(N Package)
NOTE: (1) For REG101A-A: voltage setting resistor pin. All other models: noise reduction capacitor pin.
(2) Both pin 1 and pin 2 must be connected.
(3) Both pin 7 and pin 8 must be connected.
REG101
5
SBVS026C
TYPICAL CHARACTERISTICS
For all models, at T
J
= +25
C and V
ENABLE
= 1.8V, unless otherwise noted.
20
0
40
10
30
60
50
70
80
90
100
0.80
0.60
0.40
0.20
0.00
0.20
0.40
0.60
0.80
Output Voltage Change (%)
I
OUT
(mA)
OUTPUT VOLTAGE CHANGE vs I
OUT
(V
IN
= V
OUT
+ 1V, Output Voltage % Change
Refered to I
OUT
= 50mA at +25
C)
55
C
+125
C
+25
C
25
50
0
75
25
50
100
125
0.0%
0.1%
0.2%
0.3%
0.4%
Output Voltage Change (%)
Temperature (
C)
LOAD REGULATION vs TEMPERATURE
(V
IN
= V
OUT
+ 1V)
10mA < I
OUT
< 100mA
2mA < I
OUT
< 1000mA
50
25
0
25
50
75
100
125
0.10
0.08
0.06
0.04
0.02
0.00
0.02
0.04
0.06
0.08
0.10
Output Voltage Change (%)
Temperature (
C)
LINE REGULATION vs TEMPERATURE
I
OUT
= 100mA
(V
OUT
+ 1V) < V
IN
< 10V
(V
OUT
+ 0.4V) < V
IN
< 10V
0
10
100
100
80
60
40
20
0
DC Dropout Voltage (mV)
I
OUT
(mA)
DC DROPOUT VOLTAGE vs I
OUT
20
30
40
50
60
70
80
90
55
C
+125
C
+25
C
0
1
2
3
4
5
8
6
7
20
15
10
5
0
5
10
15
20
Output Voltage Change (mV)
V
IN
V
OUT
(V)
LINE REGULATION
(Referred to V
IN
= V
OUT
+ 1V at I
OUT
= 50mA)
I
OUT
= 2mA
I
OUT
= 50mA
I
OUT
= 100mA
50
125
100
75
50
25
0
25
100
80
60
40
20
0
DC Dropout Voltage (mV)
Temperature (
C)
DC DROPOUT VOLTAGE vs TEMPERATURE
I
OUT
= 100mA
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