LP3995 Micropower 150mA CMOS Voltage Regulator with Active Shutdown
January 4, 2008
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 de-
vices, 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 al-
lows 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 µF ce-
ramic 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 −40°C to +125°C temperature
range.
The device is available in micro SMD package and LLP pack-
age. 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
■
■
■
■
■
■
■
■
■
2.5V to 6.0V Input Range
Accurate Output Voltage; ±75mV / 2%
60 mV Typical Dropout with 150 mA Load
Virtually Zero Quiescent Current when Disabled
Low Output Voltage Noise
Stable with a 1 µF Output Capacitor
Guaranteed 150 mA Output Current
Fast Turn-on; 30 µs (Typ.)
Fast Turn-off; 175 µs (Typ.)
Features
■
■
■
■
■
■
■
■
5 pin micro SMD Package
6 pin LLP Package
Stable with Ceramic Capacitor
Logic Controlled Enable
Fast Turn-on
Active Disable for Fast Turn-off.
Thermal-overload and Short-circuit Protection
−40 to +125°C Junction Temperature Range for Operation
Applications
■
■
■
■
■
GSM Portable Phones
CDMA Cellular Handsets
Wideband CDMA Cellular Handsets
Bluetooth Devices
Portable Information Appliances
Typical Application Circuit
20034901
© 2008 National Semiconductor Corporation
200349
www.national.com
LP3995
Block Diagram
20034902
Pin Descriptions
5 Pin micro SMD and LLP - 6
Pin No.
micro
SMD
A1
B2
C1
C3
A3
LLP
3
2
6
1
4
5
Pad
V
EN
GND
V
OUT
V
IN
C
BYPASS
N/C
GND
Enable Input; Disables the Regulator when
≤
0.4V.
Enables the regulator when
≥
0.9V
Common Ground
Voltage output. Connect this output to the load circuit.
Voltage Supply Input
Bypass Capacitor connection.
Connect a 0.01 µF capacitor for noise reduction.
No internal connection. There should not be any board connection to this pin.
Ground connection.
Connect to ground plane for best thermal conduction.
Symbol
Name and Function
Connection Diagrams
micro SMD, 5 Bump Package
20034903
Top View
See NS Package Number TLA05
www.national.com
2
LP3995
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
)
Output Voltage
−0.3 to 6.5V
−0.3 to (V
IN
+ 0.3V)
to 6.5V (max)
−0.3 to 6.5V
150°C
Operating Ratings
Input Voltage (V
IN
)
Enable Input Voltage
Junction Temperature
Ambient Temperature Range
(Note 7)
(Note 3)
2.5 to 6.0V
0 to 6.0V
−40 to +125°C
-40 to 85°C
Thermal Properties
Junction to Ambient Thermal
Resistance
θ
JA
(LLP pkg.)
θ
JA
(micro SMD pkg.)
(Note 8)
Enable Input Voltage
Junction Temperature
Lead/Pad Temperature
(Note 5)
micro SMD
260°C
LLP
235°C
Storage Temperature
−65 to +150°C
Continuous Power Dissipation Internally Limited
(Note 7)
ESD (Note 9)
Human Body Model
2 kV
Machine Model
200V
88°C/W
255°C/W
Electrical Characteristics
Unless otherwise noted, V
EN
= 1.5, V
IN
= V
OUT
+ 1.0V, C
IN
= 1 µF, I
OUT
= 1 mA, C
OUT
= 1 µF, c
BP
= 0.01 µF. Typical values and
limits appearing in normal type apply for T
J
= 25°C. Limits appearing in
boldface
type apply over the full temperature range for
operation, −40 to +125°C. (Notes 14, 15)
Symbol
V
IN
ΔV
OUT
Parameter
Input Voltage
Conditions
Typical
Limit
Min
2.5
Max
6.0
Units
V
DEVICE OUTPUT: 1.5
≤
V
OUT
< 1.8V
Output Voltage Tolerance
Line Regulation Error
micro SMD
Load Regulation Error
LLP
Load Regulation Error
PSRR
Power Supply Rejection Ratio
(Note 11)
I
OUT
= 1 mA
V
IN
= (V
OUT(NOM)
+1.0V) to 6.0V,
I
OUT
= 1 mA
I
OUT
= 1 mA to 150 mA
I
OUT
= 1 mA to 150 mA
f = 1 kHz, I
OUT
= 1 mA
f = 10 kHz, I
OUT
= 1 mA
I
OUT
= 1 mA
V
IN
= (V
OUT(NOM)
+1.0V) to 6.0V,
I
OUT
= 1 mA
V
IN
= (V
OUT(NOM)
+1.0V) to 6.0V,
I
OUT
= 1 mA
I
OUT
= 1 mA to 150 mA
I
OUT
= 1 mA to 150 mA
f = 1 kHz, I
OUT
= 1 mA
f = 10 kHz, I
OUT
= 1 mA
10
80
55
50
10
70
55
53
-50
-75
-3.5
50
75
3.5
75
125
mV
mV/V
µV/mA
µV/mA
dB
DEVICE OUTPUT: 1.8
≤
V
OUT
< 2.5V
ΔV
OUT
Output Voltage Tolerance
microSMDLine
Regulation Error
LLP
Line Regulation Error
micro SMD
Load Regulation Error
LLP
Load Regulation Error
PSRR
Power Supply Rejection Ratio
(Note 11)
-50
−75
−2.5
−3.5
50
75
2.5
3.5
75
125
mV
mV/V
mV/V
µV/mA
µV/mA
dB
5
www.national.com
Microcontroller MCU
京公网安备 11010802033920号
EEWORLD
