LP3995
Micropower 150mA CMOS Voltage Regulator with Active
Shutdown
General Description
The LP3995 linear regulator is designed to meet the require-
ments of portable battery-powered applications and will pro-
vide an accurate output voltage with low noise and low
quiescent current. Ideally suited for powering RF/Analog
devices, this device will also be used to meet more general
circuit needs in which a fast turn-off is essential.
For battery powered applications the low dropout and low
ground current provided by the device allows the lifetime of
the battery to be maximized. The Enable(/Disable) control
allows the system to further extend the battery lifetime by
reducing the power consumption to virtually zero.
The Enable(/Disable) function on the device incorporates an
active discharge circuit on the output for faster device shut-
down. Where the fast turn-off is not required the LP3999
linear regulator is recommended.
The LP3995 also features internal protection against short-
circuit currents and over-temperature conditions.
The LP3995 is designed to be stable with small 1.0 F
ceramic capacitors. The small outline of the LP3995 micro
SMD package with the required ceramic capacitors can
realize a system application within minimal board area.
Performance is specified for a -40C to +125C temperature
range.
The device is available in micro SMD package and LLP
package. For other package options contact your local NSC
sales office.
The device is available in fixed output voltages in the ranges
1.5V to 3.3V. For availability, please contact your local NSC
sales office.
Key Specifications
n
2.5V to 6.0V Input Range
n
Accurate Output Voltage;
75mV / 2%
n
60 mV Typical Dropout with 150 mA Load
n
Virtually Zero Quiescent Current when Disabled
n
Low Output Voltage Noise
n
Stable with a 1 F Output Capacitor
n
Guaranteed 150 mA Output Current
n
Fast Turn-on; 30 s (Typ.)
n
Fast Turn-off; 175 s (Typ.)
Features
n
5 pin micro SMD Package
n
6 pin LLP Package
n
Stable with Ceramic Capacitor
n
Logic Controlled Enable
n
Fast Turn-on
n
Active Disable for Fast Turn-off.
n
Thermal-overload and Short-circuit Protection
n
-40 to +125C Junction Temperature Range for
Operation
Applications
n
GSM Portable Phones
n
CDMA Cellular Handsets
n
Wideband CDMA Cellular Handsets
n
Bluetooth Devices
n
Portable Information Appliances
Typical Application Circuit
20034901
August 2004
LP3995
Micropower
150mA
CMOS
V
oltage
Regulator
with
Active
Shutdown
2004 National Semiconductor Corporation
DS200349
www.national.com
Block Diagram
20034902
Pin Description
5 pin micro SMD and LLP - 6
Pin No.
Symbol
Name and Function
micro
SMD
LLP
A1
3
V
EN
Enable Input; Disables the Regulator when
0.4V.
Enables the regulator when
0.9V
B2
2
GND
Common Ground
C1
6
V
OUT
Voltage output. Connect this output to the load circuit.
C3
1
V
IN
Voltage Supply Input
A3
4
C
BYPASS
Bypass Capacitor connection.
Connect a 0.01 F capacitor for noise reduction.
5
N/C
No internal connection. There should not be any board connection to this pin.
Pad
GND
Ground connection.
Connect to ground plane for best thermal conduction.
Connection Diagrams
micro SMD, 5 Bump Package
20034903
Top View
See NS Package Number TLA05
LP3995
www.national.com
2
Absolute Maximum Ratings
(Notes 3, 4)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Input Voltage (V
IN
)
-0.3 to 6.5V
Output Voltage
-0.3 to (V
IN
+ 0.3V)
to 6.5V (max)
Enable Input Voltage
-0.3 to 6.5V
Junction Temperature
150C
Lead/Pad Temperature
(Note 5)
micro SMD
260C
LLP
235C
Storage Temperature
-65 to +150C
Continuous Power
Dissipation(Note 7)
Internally Limited
ESD (Note 9)
Human Body Model
2 kV
Machine Model
200V
Operating Ratings
(Note 3)
Input Voltage (V
IN
)
2.5 to 6.0V
Enable Input Voltage
0 to 6.0V
Junction Temperature
-40 to +125C
Ambient Temperature
Range(Note 7)
-40 to 85C
Thermal Properties
(Note 8)
Junction to Ambient Thermal
Resistance
JA
(LLP pkg.)
88C/W
JA
(micro SMD pkg.)
255C/W
Electrical Characteristics
Unless otherwise noted, V
EN
= 1.5, V
IN
= V
OUT
+ 1.0V, C
IN
= 1 F, I
OUT
= 1 mA, C
OUT
= 1 F, c
BP
= 0.01 F. Typical values
and limits appearing in normal type apply for T
J
= 25C. Limits appearing in boldface type apply over the full temperature
range for operation, -40 to +125C. (Notes 14, 15)
Symbol
Parameter
Conditions
Typical
Limit
Units
Min
Max
V
IN
Input Voltage
2.5
6.0
V
DEVICE OUTPUT: 1.5
V
OUT
<
1.8V
V
OUT
Output Voltage Tolerance
I
OUT
= 1 mA
-50
50
mV
-75
75
Line Regulation Error
V
IN
= (V
OUT(NOM)
+1.0V) to 6.0V,
I
OUT
= 1 mA
-3.5
3.5
mV/V
micro SMD
Load Regulation Error
I
OUT
= 1 mA to 150 mA
10
75
V/mA
LLP
Load Regulation Error
I
OUT
= 1 mA to 150 mA
70
125
V/mA
PSRR
Power Supply Rejection Ratio
(Note 11)
f = 1 kHz, I
OUT
= 1 mA
55
dB
f = 10 kHz, I
OUT
= 1 mA
53
DEVICE OUTPUT: 1.8
V
OUT
<
2.5V
V
OUT
Output Voltage Tolerance
I
OUT
= 1 mA
-50
50
mV
-75
75
microSMDLine Regulation Error
V
IN
= (V
OUT(NOM)
+1.0V) to 6.0V,
I
OUT
= 1 mA
-2.5
2.5
mV/V
LLP
Line Regulation Error
V
IN
= (V
OUT(NOM)
+1.0V) to 6.0V,
I
OUT
= 1 mA
-3.5
3.5
mV/V
micro SMD
Load Regulation Error
I
OUT
= 1 mA to 150 mA
10
75
V/mA
LLP
Load Regulation Error
I
OUT
= 1 mA to 150 mA
80
125
V/mA
PSRR
Power Supply Rejection Ratio
(Note 11)
f = 1 kHz, I
OUT
= 1 mA
55
dB
f = 10 kHz, I
OUT
= 1 mA
50
LP3995
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