LP3995ILDX-3.0 [NSC]

Micropower 150mA CMOS Voltage Regulator with Active Shutdown; 微150毫安CMOS电压稳压器与Active关闭
LP3995ILDX-3.0
型号: LP3995ILDX-3.0
厂家: National Semiconductor    National Semiconductor
描述:

Micropower 150mA CMOS Voltage Regulator with Active Shutdown
微150毫安CMOS电压稳压器与Active关闭

稳压器
文件: 总14页 (文件大小:353K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
August 2004  
LP3995  
Micropower 150mA CMOS Voltage Regulator with Active  
Shutdown  
General Description  
Key Specifications  
n 2.5V to 6.0V Input Range  
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.  
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 µF Output Capacitor  
n Guaranteed 150 mA Output Current  
n Fast Turn-on; 30 µs (Typ.)  
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.  
n Fast Turn-off; 175 µs (Typ.)  
Features  
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.  
n 5 pin micro SMD Package  
n 6 pin LLP Package  
n Stable with Ceramic Capacitor  
n Logic Controlled Enable  
n Fast Turn-on  
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  
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.  
n Active Disable for Fast Turn-off.  
n Thermal-overload and Short-circuit Protection  
n
−40 to +125˚C Junction Temperature Range for  
Operation  
Performance is specified for a −40˚C to +125˚C temperature  
range.  
Applications  
The device is available in micro SMD package and LLP  
package. For other package options contact your local NSC  
sales office.  
n GSM Portable Phones  
n CDMA Cellular Handsets  
n Wideband CDMA Cellular Handsets  
n Bluetooth Devices  
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.  
n Portable Information Appliances  
Typical Application Circuit  
20034901  
© 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  
LLP  
SMD  
A1  
3
VEN  
Enable Input; Disables the Regulator when 0.4V.  
Enables the regulator when 0.9V  
Common Ground  
B2  
C1  
C3  
A3  
2
6
1
4
GND  
VOUT  
Voltage output. Connect this output to the load circuit.  
Voltage Supply Input  
VIN  
CBYPASS  
Bypass Capacitor connection.  
Connect a 0.01 µF capacitor for noise reduction.  
5
N/C  
No internal connection. There should not be any board connection to this pin.  
Ground connection.  
Pad  
GND  
Connect to ground plane for best thermal conduction.  
Connection Diagrams  
micro SMD, 5 Bump Package  
20034903  
Top View  
See NS Package Number TLA05  
www.national.com  
2
Connection Diagrams (Continued)  
LLP- 6 Package (SOT23 Footprint)  
20034904  
Top View  
See NS Package Number LDE06A  
3
www.national.com  
Ordering Information  
For micro SMD Package  
LP3995 Supplied as 250  
Output Voltage  
(V)  
Grade  
LP3995 Supplied as  
3000 Units, Tape and  
Reel  
Package  
Marking  
Units, Tape and Reel  
1.5  
1.6  
1.8  
1.9  
2.1  
2.5  
2.8  
2.85  
3.0  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
LP3995ITL-1.5  
LP3995ITL-1.6  
LP3995ITL-1.8  
LP3995ITL-1.9  
LP3995ITL-2.1  
LP3995ITL-2.5  
LP3995ITL-2.8  
LP3995ITL-2.85  
LP3995ITL-3.0  
LP3995ITLX-1.5  
LP3995ITLX-1.6  
LP3995ITLX-1.8  
LP3995ITLX-1.9  
LP3995ITLX-2.1  
LP3995ITLX-2.5  
LP3995ITLX-2.8  
LP3995ITLX-2.85  
LP3995ITLX-3.0  
For micro SMD Package unleaded  
Output Voltage  
(V)  
Grade  
LP3995 Supplied as 250  
Units, Tape and Reel  
LP3995 Supplied as  
3000 Units, Tape and  
Reel  
Package  
Marking  
1.5 (Note 2)  
1.6 (Note 2)  
1.8 (Note 2)  
1.9 (Note 2)  
2.1 (Note 2)  
2.5 (Note 2)  
2.8 (Note 2)  
3.0 (Note 2)  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
LP3995ITL-1.5  
LP3995ITL-1.6  
LP3995ITL-1.8  
LP3995ITL-1.9  
LP3995ITL-2.1  
LP3995ITL-2.5  
LP3995ITL-2.8  
LP3995ITL-3.0  
LP3995ITLX-1.5  
LP3995ITLX-1.6  
LP3995ITLX-1.8  
LP3995ITLX-1.9  
LP3995ITLX-2.1  
LP3995ITLX-2.5  
LP3995ITLX-2.8  
LP3995ITLX-3.0  
For LLP- 6 Package  
Output Voltage  
(V)  
Grade  
LP3995 Supplied as 1000  
Units, Tape and Reel  
LP3995 Supplied as  
4500 Units, Tape and  
Reel  
Package  
Marking  
1.5  
1.6  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
STD  
LP3995ILD-1.5  
LP3995ILD-1.6  
LP3995ILD-1.8  
LP3995ILD-1.9  
LP3995ILD-2.1  
LP3995ILD-2.5  
LP3995ILD-2.8  
LP3995ILD-3.0  
LP3995ILD-3.3  
LP3995ILDX-1.5  
LP3995ILDX-1.6  
LP3995ILDX-1.8  
LP3995ILDX-1.9  
LP3995ILDX-2.1  
LP3995ILDX-2.5  
LP3995ILDX-2.8  
LP3995ILDX-3.0  
LP3995ILDX-3.3  
LO20B  
LO21B  
LO22B  
LO23B  
LO24B  
LO25B  
LO26B  
LO30B  
LO31B  
1.8  
1.9 (Note 2)  
2.1 (Note 2)  
2.5 (Note 2)  
2.8  
3.0  
3.3 (Note 2)  
Note 1: Available in sample quantities only  
Note 2: For availability contact your local sales office  
www.national.com  
4
Absolute Maximum Ratings  
(Notes 3, 4)  
Operating Ratings (Note 3)  
Input Voltage (VIN  
)
2.5 to 6.0V  
0 to 6.0V  
If Military/Aerospace specified devices are required,  
please contact the National Semiconductor Sales Office/  
Distributors for availability and specifications.  
Enable Input Voltage  
Junction Temperature  
Ambient Temperature  
Range(Note 7)  
−40 to +125˚C  
-40 to 85˚C  
Input Voltage (VIN  
Output Voltage  
)
−0.3 to 6.5V  
−0.3 to (VIN + 0.3V)  
to 6.5V (max)  
−0.3 to 6.5V  
Thermal Properties(Note 8)  
Junction to Ambient Thermal  
Resistance  
Enable Input Voltage  
Junction Temperature  
Lead/Pad Temperature  
(Note 5)  
150˚C  
θJA (LLP pkg.)  
88˚C/W  
θJA (micro SMD pkg.)  
255˚C/W  
micro SMD  
260˚C  
235˚C  
LLP  
Storage Temperature  
Continuous Power  
Dissipation(Note 7)  
ESD (Note 9)  
−65 to +150˚C  
Internally Limited  
Human Body Model  
Machine Model  
2 kV  
200V  
Electrical Characteristics  
Unless otherwise noted, VEN = 1.5, VIN = VOUT + 1.0V, CIN = 1 µF, IOUT = 1 mA, COUT = 1 µF, cBP = 0.01 µF. Typical values  
and limits appearing in normal type apply for TJ = 25˚C. Limits appearing in boldface type apply over the full temperature  
range for operation, −40 to +125˚C. (Notes 14, 15)  
Limit  
Symbol  
Parameter  
Conditions  
Typical  
Units  
Min  
Max  
VIN  
Input Voltage  
2.5  
6.0  
V
<
DEVICE OUTPUT: 1.5 VOUT 1.8V  
VOUT  
Output Voltage Tolerance  
IOUT = 1 mA  
-50  
50  
mV  
-75  
75  
Line Regulation Error  
VIN = (VOUT(NOM)+1.0V) to 6.0V,  
IOUT = 1 mA  
-3.5  
3.5  
75  
mV/V  
micro SMD  
Load Regulation Error  
LLP  
Load Regulation Error  
Power Supply Rejection Ratio  
(Note 11)  
IOUT = 1 mA to 150 mA  
µV/mA  
10  
70  
IOUT = 1 mA to 150 mA  
µV/mA  
dB  
125  
PSRR  
f = 1 kHz, IOUT = 1 mA  
f = 10 kHz, IOUT = 1 mA  
55  
53  
<
DEVICE OUTPUT: 1.8 VOUT 2.5V  
VOUT  
Output Voltage Tolerance  
IOUT = 1 mA  
-50  
50  
mV  
−75  
75  
microSMDLine Regulation Error VIN = (VOUT(NOM)+1.0V) to 6.0V,  
−2.5  
−3.5  
2.5  
3.5  
75  
mV/V  
IOUT = 1 mA  
LLP  
VIN = (VOUT(NOM)+1.0V) to 6.0V,  
IOUT = 1 mA  
mV/V  
Line Regulation Error  
micro SMD  
IOUT = 1 mA to 150 mA  
µV/mA  
10  
80  
Load Regulation Error  
LLP  
IOUT = 1 mA to 150 mA  
µV/mA  
dB  
125  
Load Regulation Error  
Power Supply Rejection Ratio  
(Note 11)  
PSRR  
f = 1 kHz, IOUT = 1 mA  
f = 10 kHz, IOUT = 1 mA  
55  
50  
5
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Electrical Characteristics (Continued)  
Unless otherwise noted, VEN = 1.5, VIN = VOUT + 1.0V, CIN = 1 µF, IOUT = 1 mA, COUT = 1 µF, cBP = 0.01 µF. Typical values  
and limits appearing in normal type apply for TJ = 25˚C. Limits appearing in boldface type apply over the full temperature  
range for operation, −40 to +125˚C. (Notes 14, 15)  
Limit  
Symbol  
Parameter  
Conditions  
Typical  
Units  
Min  
Max  
DEVICE OUTPUT: 2.5 VOUT 3.3V  
VOUT  
Output Voltage Tolerance  
Line Regulation Error  
IOUT = 1 mA  
-2  
2
% of  
VOUT(NOM)  
−3  
3
VIN = (VOUT(NOM)+1.0V) to 6.0V,  
IOUT = 1 mA  
−0.1  
0.1  
%/V  
%/mA  
%/mA  
mV  
micro SMD  
Load Regulation Error  
LLP  
Load Regulation Error  
Dropout Voltage  
IOUT = 1 mA to 150 mA  
0.0004  
0.002  
0.002  
0.005  
IOUT = 1 mA to 150 mA  
IOUT = 1 mA  
0.4  
60  
60  
50  
2
IOUT = 150 mA  
100  
PSRR  
Power Supply Rejection Ratio  
(Note 11)  
f = 1 kHz, IOUT = 1 mA  
f = 10 kHz, IOUT = 1 mA  
dB  
FULL VOUT RANGE  
ILOAD Load Current  
IQ  
(Notes 10, 11)  
0
µA  
µA  
Quiescent Current  
VEN = 1.5V, IOUT = 0 mA  
VEN = 1.5V, IOUT = 150 mA  
VEN = 0.4V  
85  
140  
150  
200  
1.5  
0.003  
450  
ISC  
EN  
Short Circuit Current Limit  
mA  
µVrms  
˚C  
Output Noise Voltage ((Note 11)) BW = 10 Hz to 100 kHz,  
VIN = 4.2V, IOUT = 1mA  
25  
TSHUTDOWN  
Thermal Shutdown  
Temperature  
Hysteresis  
160  
20  
ENABLE CONTROL CHARACTERISTICS  
IEN  
Maximum Input Current at  
VEN Input  
VEN = 0.0V and VIN = 6.0V  
0.001  
µA  
VIL  
VIH  
Low Input Threshold  
High Input Threshold  
0.4  
V
V
0.9  
TIMING CHARACTERISTICS  
TON  
Turn On Time (Note 11)  
Turn Off Time (Note 11)  
To 95% Level (Note 12)  
To 5% Level (Note 13)  
30  
µs  
µs  
TOFF  
175  
Note 3: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device  
is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical  
Characteristics tables.  
Note 4: All voltages are with respect to the potential at the GND pin.  
Note 5: For information regarding micro SMD and LLP packages please refer to the following application notes;  
AN-1112 Micro SMD Package Wafer Level Chip Scale Package,  
AN-1187. Leadless Leadframe Package.  
Note 6: Internal Thermal shutdown circuitry protects the device from permanent damage.  
Note 7: In applications where high power dissipation and/or poor thermal resistance is present, the maximum ambient temperature may have to be derated.  
Maximum ambient temperature (T  
) is dependant on the maximum operating junction temperature (T  
), the maximum power dissipation (P  
), and  
A(max)  
J(max-op)  
D(max)  
the junction to ambient thermal resistance in the application (θ ). This relationship is given by :-  
JA  
TA(max) = TJ(max-op) − (PD(max) x θJA  
)
Note 8: Junction to ambient thermal resistance is highly dependant on the application and board layout. In applications where high thermal dissipation is possible,  
special care must be paid to thermal issues in the board design.  
Note 9: The human body model is an 100 pF discharge through a 1.5 kresistor into each pin. The machine model is a 200 pF capacitor discharged directly into  
each pin.  
Note 10: The device maintains a stable, regulated output voltage without load.  
Note 11: This electrical specification is guaranteed by design.  
Note 12: Time from V = 0.9V to V  
= 95% (V  
)
OUT(NOM)  
EN  
OUT  
OUT  
Note 13: Time from V = 0.4V to V  
= 5% (V  
)
EN  
OUT(NOM)  
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6
Electrical Characteristics (Continued)  
Note 14: All limits are guaranteed. All electrical characteristics having room-temperature limits are tested during production at T = 25˚C or correlated using  
J
Statistical Quality Control methods. Operation over the temperature specification is guaranteed by correlating the electrical characteristics to process and  
temperature variations and applying statistical process control.  
Note 15: V  
is the stated output voltage option for the device.  
OUT(NOM)  
Recommended Output Capacitor  
Limit  
Symbol  
COUT  
Parameter  
Output Capacitor  
Conditions  
VALUE  
Units  
Min  
0.70  
5
Max  
Capacitance (Note 16)  
ESR  
1.0  
µF  
500  
mΩ  
Note 16: The capacitor tolerance should be 30% or better over the temperature range. The recommended capacitor type is X7R however, dependant on the  
application X5R, Y5V, and Z5U can also be used.  
Input Test Signals  
20034906  
FIGURE 1. Line Transient Response Input Test Signal  
20034907  
FIGURE 2. PSRR Input Test Signal  
7
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Typical Performance Characteristics Unless otherwise specified, CIN = COUT = 1.0 µF Ceramic, VIN  
= VOUT + 1.0V, TA = 25˚C, Enable pin is tied to VIN  
.
Output Voltage Change vs Temperature  
Ground Current vs Load Current (1.8V VOUT)  
20034910  
20034911  
@
Ground Current vs VIN 25˚C  
Ground Current vs Load Current (2.8V VOUT  
)
20034912  
20034913  
@
Ground Current vs VIN 125˚C  
Dropout vs Load Current  
20034915  
20034914  
www.national.com  
8
Typical Performance Characteristics Unless otherwise specified, CIN = COUT = 1.0 µF Ceramic, VIN  
= VOUT + 1.0V, TA = 25˚C, Enable pin is tied to VIN. (Continued)  
Short Circuit Current  
Line Transient Response (VOUT = 2.8V)  
20034916  
20034917  
Ripple Rejection (VOUT = 1.8V)  
Ripple Rejection (VOUT = 2.8V)  
20034918  
20034919  
Enable Start-Up Time (VOUT = 2.8V)  
Enable Start-Up Time (VOUT = 2.8V)  
20034920  
20034921  
9
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Typical Performance Characteristics Unless otherwise specified, CIN = COUT = 1.0 µF Ceramic, VIN  
= VOUT + 1.0V, TA = 25˚C, Enable pin is tied to VIN. (Continued)  
Enable Start-Up Time (VOUT = 1.8V)  
Enable Start-Up Time (VOUT = 1.8V)  
20034922  
20034923  
Turn-Off Time (VOUT = 2.8V)  
Turn-Off Time (VOUT = 1.8V)  
20034924  
20034925  
Load Transient Response (VOUT = 2.8V)  
Load Transient Response (VOUT = 1.8V)  
20034926  
20034927  
www.national.com  
10  
OUTPUT CAPACITOR  
Application Hints  
The LP3995 is designed specifically to work with very small  
ceramic output capacitors. A ceramic capacitor (dielectric  
types Z5U, Y5V or X7R) in the 1.0 [to 10 µF] range, and with  
ESR between 5 mto 500 m, is suitable in the LP3995  
application circuit.  
POWER DISSIPATION AND DEVICE OPERATION  
The permissible power dissipation for any package is a  
measure of the capability of the device to pass heat from the  
power source, the junctions of the IC, to the ultimate heat  
sink, the ambient environment. Thus the power dissipation is  
dependent on the ambient temperature and the thermal  
resistance across the various interfaces between the die and  
ambient air.  
For this device the output capacitor should be connected  
between the VOUT pin and ground.  
It may also be possible to use tantalum or film capacitors at  
the device output, VOUT, but these are not as attractive for  
reasons of size and cost (see the section Capacitor Charac-  
teristics).  
The Thermal Resistance figure  
Re-stating the equation in (Note 7) in the electrical specifi-  
cation section, the allowable power dissipation for the device  
in a given package can be calculated:  
The output capacitor must meet the requirement for the  
minimum value of capacitance and also have an ESR value  
that is within the range 5 mto 500 mfor stability.  
NO-LOAD STABILITY  
The LP3995 will remain stable and in regulation with no  
external load. This is an important consideration in some  
circuits, for example CMOS RAM keep-alive applications.  
With a θJA = 255˚C/W, the device in the micro SMD package  
returns a value of 392 mW with a maximum junction tem-  
perature of 125˚C.  
CAPACITOR CHARACTERISTICS  
With a θJA = 88˚C/W, the device in the LLP package returns  
a value of 1.136 mW with a maximum junction temperature  
of 125˚C.  
The LP3995 is designed to work with ceramic capacitors on  
the output to take advantage of the benefits they offer. For  
capacitance values in the range of 1 µF to 4.7 µF, ceramic  
capacitors are the smallest, least expensive and have the  
lowest ESR values, thus making them best for eliminating  
high frequency noise. The ESR of a typical 1 µF ceramic  
capacitor is in the range of 20 mto 40 m, which easily  
meets the ESR requirement for stability for the LP3995.  
The actual power dissipation across the device can be rep-  
resented by the following equation:  
PD = (VIN − VOUT) x IOUT  
.
This establishes the relationship between the power dissipa-  
tion allowed due to thermal consideration, the voltage drop  
across the device, and the continuous current capability of  
the device. These two equations should be used to deter-  
mine the optimum operating conditions for the device in the  
application.  
The temperature performance of ceramic capacitors varies  
by type. Most large value ceramic capacitors ( 2.2 µF) are  
manufactured with Z5U or Y5V temperature characteristics,  
which results in the capacitance dropping by more than 50%  
as the temperature goes from 25˚C to 85˚C.  
A better choice for temperature coefficient in a ceramic  
capacitor is X7R. This type of capacitor is the most stable  
and holds the capacitance within 15% over the tempera-  
ture range. Tantalum capacitors are less desirable than ce-  
ramic for use as output capacitors because they are more  
expensive when comparing equivalent capacitance and volt-  
age ratings in the 1 µF to 4.7 µF range.  
EXTERNAL CAPACITORS  
In common with most regulators, the LP3995 requires exter-  
nal capacitors to ensure stable operation. The LP3995 is  
specifically designed for portable applications requiring mini-  
mum board space and smallest components. These capaci-  
tors must be correctly selected for good performance.  
Another important consideration is that tantalum capacitors  
have higher ESR values than equivalent size ceramics. This  
means that while it may be possible to find a tantalum  
capacitor with an ESR value within the stable range, it would  
have to be larger in capacitance (which means bigger and  
more costly) than a ceramic capacitor with the same ESR  
value. It should also be noted that the ESR of a typical  
tantalum will increase about 2:1 as the temperature goes  
from 25˚C down to −40˚C, so some guard band must be  
allowed.  
INPUT CAPACITOR  
An input capacitor is required for stability. It is recommended  
that a 1.0 µF capacitor be connected between the LP3995  
input pin and ground (this capacitance value may be in-  
creased without limit).  
This capacitor must be located a distance of not more than  
1 cm from the input pin and returned to a clean analogue  
ground. Any good quality ceramic, tantalum, or film capacitor  
may be used at the input.  
Important: Tantalum capacitors can suffer catastrophic fail-  
ures due to surge current when connected to a low-  
impedance source of power (like a battery or a very large  
capacitor). If a tantalum capacitor is used at the input, it must  
be guaranteed by the manufacturer to have a surge current  
rating sufficient for the application.  
NOISE BYPASS CAPACITOR  
A bypass capacitor should be connected between the CBP  
pin and ground to significantly reduce the noise at the regu-  
lator output. This device pin connects directly to a high  
impedance node within the bandgap reference circuitry. Any  
significant loading on this node will cause a change on the  
regulated output voltage. For this reason, DC leakage cur-  
rent through this pin must be kept as low as possible for best  
output voltage accuracy.  
There are no requirements for the ESR (Equivalent Series  
Resistance) on the input capacitor, but tolerance and tem-  
perature coefficient must be considered when selecting the  
capacitor to ensure the capacitance will remain 1.0 µF over  
the entire operating temperature range.  
The use of a 0.01uF bypass capacitor is strongly recom-  
mended to prevent overshoot on the output during start-up.  
11  
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within the reference block allowing a very fast ramp of the  
output voltage to reach the target voltage.  
Application Hints (Continued)  
The types of capacitors best suited for the noise bypass  
capacitor are ceramic and film. High quality ceramic capaci-  
tors with NPO or COG dielectric typically have very low  
leakage. Polypropolene and polycarbonate film capacitors  
are available in small surface-mount packages and typically  
have extremely low leakage current.  
micro SMD MOUNTING  
The micro SMD package requires specific mounting tech-  
niques which are detailed in National Semiconductor Appli-  
cation Note AN-1112.  
Referring to the section Surface Mount Technology (SMT)  
Assembly Considerations, it should be noted that the pad  
style which must be used with the 5 pin package is NSMD  
(non-solder mask defined) type.  
Unlike many other LDO’s, the addition of a noise reduction  
capacitor does not effect the transient response of the de-  
vice.  
For best results during assembly, alignment ordinals on the  
PC board may be used to facilitate placement of the micro  
SMD device.  
ENABLE OPERATION  
The LP3995 may be switched ON or OFF by a logic input at  
the ENABLE pin, VEN. A high voltage at this pin will turn the  
device on. When the enable pin is low, the regulator output is  
off and the device typically consumes 3 nA. If the application  
does not require the shutdown feature, the VEN pin should  
be tied to VIN to keep the regulator output permanently on.  
To ensure proper operation, the signal source used to drive  
the VEN input must be able to swing above and below the  
specified turn-on/off voltage thresholds listed in the Electrical  
micro SMD LIGHT SENSITIVITY  
Exposing the micro SMD device to direct sunlight will cause  
incorrect operation of the device. Light sources such as  
halogen lamps can affect electrical performance if they are  
situated in proximity to the device.  
Light with wavelengths in the red and infra-red part of the  
spectrum have the most detrimental effect thus the fluores-  
cent lighting used inside most buildings has very little effect  
on performance. Tests carried out on a micro SMD test  
board showed a negligible effect on the regulated output  
voltage when brought within 1 cm of a fluorescent lamp. A  
deviation of less than 0.1% from nominal output voltage was  
observed.  
Characteristics section under VIL and VIH  
.
FAST TURN OFF AND ON  
The controlled switch-off feature of the device provides a fast  
turn off by discharging the output capacitor via an internal  
FET device. This discharge is current limited by the RDSon  
of this switch. Fast turn-on is guaranteed by control circuitry  
www.national.com  
12  
Physical Dimensions inches (millimeters) unless otherwise noted  
micro SMD, 5 Bump, Package (TLA05)  
NS Package Number TLA05ADA  
The dimensions for X1, X2 and X3 are given as:  
X1 = 1.006 +/− 0.03mm  
X2 = 1.438 +/− 0.03mm  
X3 = 0.600 +/− 0.075mm  
13  
www.national.com  
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)  
LLP, 6 Lead, Package (SOT23 Land)  
NS Package Number LDE06A  
LIFE SUPPORT POLICY  
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT  
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL  
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:  
1. Life support devices or systems are devices or  
systems which, (a) are intended for surgical implant  
into the body, or (b) support or sustain life, and  
whose failure to perform when properly used in  
accordance with instructions for use provided in the  
labeling, can be reasonably expected to result in a  
significant injury to the user.  
2. A critical component is any component of a life  
support device or system whose failure to perform  
can be reasonably expected to cause the failure of  
the life support device or system, or to affect its  
safety or effectiveness.  
BANNED SUBSTANCE COMPLIANCE  
National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products  
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification  
(CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2.  
National Semiconductor  
Americas Customer  
Support Center  
National Semiconductor  
Europe Customer Support Center  
Fax: +49 (0) 180-530 85 86  
National Semiconductor  
Asia Pacific Customer  
Support Center  
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Japan Customer Support Center  
Fax: 81-3-5639-7507  
Email: new.feedback@nsc.com  
Tel: 1-800-272-9959  
Email: europe.support@nsc.com  
Deutsch Tel: +49 (0) 69 9508 6208  
English Tel: +44 (0) 870 24 0 2171  
Français Tel: +33 (0) 1 41 91 8790  
Email: ap.support@nsc.com  
Email: jpn.feedback@nsc.com  
Tel: 81-3-5639-7560  
www.national.com  
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.  

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