Datasheet LP2985AIBP-2.8, LP2985AIBP-2.5, LP2985IM5X-5.0, LP2985IM5X-3.3, LP2985IM5X-2.5 Datasheet (NSC)
...
LP2985
Micropower 150 mA Low-Noise Ultra Low-Dropout
Regulator
Designed for Use with Very Low ESR Output Capacitors
General Description
The LP2985 is a 150 mA, fixed-output voltage regulator designed to provide ultra low-dropout and low noise in battery
powered applications.
Using an optimized VIP
™
(Vertically Integrated PNP) process, the LP2985 delivers unequalled performance in all
specifications critical to battery-powered designs:
Dropout Voltage: Typically 300 mV
@
150 mA load, and
7mV
@
1 mA load.
Ground Pin Current: Typically 850 µA
@
150 mA load, and
75 µA
@
1 mA load.
Enhanced Stability: The LP2985 is stable with output capacitor ESR as low as 5 mΩ, which allows the use of ceramic
capacitors on the output.
Sleep Mode: Less than 1 µA quiescent current when
ON/OFF pin is pulled low.
Smallest Possible Size: SOT-23 and micro SMD packages
use absolute minimum board space.
Precision Output: 1% tolerance output voltages available
(A grade).
Low Noise: By adding a 10 nF bypass capacitor, output
noise can be reduced to 30 µV (typical).
Multiple voltage options, from 2.5V to 5.0V, are available as
standard products. Consult factory for custom voltages.
Features
n Ultra low dropout voltage
n Guaranteed 150 mA output current
n Smallest possible size (SOT-23, micro SMD package)
n Requires minimum external components
n Stable with low-ESR output capacitor
n
<
1 µA quiescent current when shut down
n Low ground pin current at all loads
n Output voltage accuracy 1% (A Grade)
n High peak current capability
n Wide supply voltage range (16V max)
n Low Z
OUT
: 0.3Ω typical (10 Hz to 1 MHz)
n Overtemperature/overcurrent protection
n −40˚C to +125˚C junction temperature range
n Custom voltages available
Applications
n Cellular Phone
n Palmtop/Laptop Computer
n Personal Digital Assistant (PDA)
n Camcorder, Personal Stereo, Camera
Block Diagram
VIP™is a trademark of NationalSemiconductor Corporation.
DS100140-1
March 2000
LP2985 Micropower 150 mA Low-Noise Ultra Low-Dropout Regulator
© 2000 National Semiconductor Corporation DS100140 www.national.com
Basic Application Circuit
Connection Diagrams
DS100140-2
*ON/OFF input must be actively terminated. Tie to VINif this function is not to be used.
**Minimum capacitance is shown to ensure stability (may be increased without limit). Ceramic capacitor required for output (see Application Hints).
***Reduces output noise (may be omitted if application is not noise critical). Use ceramic or film type with very low leakage current (see Application Hints).
5-Lead Small Outline Package (M5)
DS100140-3
Top View
See NS Package Number MF05A
For ordering information see
Table 1
micro SMD, 5 Bump Package (BPA05)
DS100140-44
Bottom View
See NS Package Number BPA05
LP2985
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Ordering Information
TABLE 1. Package Marking and Ordering Information
Output Voltage
(V)
Grade Order Information
Package
Marking
Supplied as:
5-Lead Small Outline Package (M5)
2.5 A LP2985AIM5X-2.5 LAUA 3000 Units on Tape and Reel
2.5 A LP2985AIM5-2.5 LAUA 1000 Units on Tape and Reel
2.5 STD LP2985IM5X-2.5 LAUB 3000 Units on Tape and Reel
2.5 STD LP2985IM5-2.5 LAUB 1000 Units on Tape and Reel
2.7 A LP2985AIM5X-2.7 LALA 3000 Units on Tape and Reel
2.7 A LP2985AIM5-2.7 LALA 1000 Units on Tape and Reel
2.7 STD LP2985IM5X-2.7 LALB 3000 Units on Tape and Reel
2.7 STD LP2985IM5-2.7 LALB 1000 Units on Tape and Reel
2.8 A LP2985AIM5X-2.8 L0KA 3000 Units on Tape and Reel
2.8 A LP2985AIM5-2.8 L0KA 1000 Units on Tape and Reel
2.8 STD LP2985IM5X-2.8 L0KB 3000 Units on Tape and Reel
2.8 STD LP2985IM5-2.8 L0KB 1000 Units on Tape and Reel
2.9 A LP2985AIM5X-2.9 LAXA 3000 Units on Tape and Reel
2.9 A LP2985AIM5-2.9 LAXA 1000 Units on Tape and Reel
2.9 STD LP2985IM5X-2.9 LAXB 3000 Units on Tape and Reel
2.9 STD LP2985IM5-2.9 LAXB 1000 Units on Tape and Reel
3.0 A LP2985AIM5X-3.0 L0OA 3000 Units on Tape and Reel
3.0 A LP2985AIM5-3.0 L0OA 1000 Units on Tape and Reel
3.0 STD LP2985IM5X-3.0 L0OB 3000 Units on Tape and Reel
3.0 STD LP2985IM5-3.0 L0OB 1000 Units on Tape and Reel
3.1 A LP2985AIM5X-3.1 L0PA 3000 Units on Tape and Reel
3.1 A LP2985AIM5-3.1 L0PA 1000 Units on Tape and Reel
3.1 STD LP2985IM5X-3.1 L0PB 3000 Units on Tape and Reel
3.1 STD LP2985IM5-3.1 L0PB 1000 Units on Tape and Reel
3.2 A LP2985AIM5X-3.2 L0QA 3000 Units on Tape and Reel
3.2 A LP2985AIM5-3.2 L0QA 1000 Units on Tape and Reel
3.2 STD LP2985IM5X-3.2 L0QB 3000 Units on Tape and Reel
3.2 STD LP2985IM5-3.2 L0QB 1000 Units on Tape and Reel
3.3 A LP2985AIM5X-3.3 L0RA 3000 Units on Tape and Reel
3.3 A LP2985AIM5-3.3 L0RA 1000 Units on Tape and Reel
3.3 STD LP2985IM5X-3.3 L0RB 3000 Units on Tape and Reel
3.3 STD LP2985IM5-3.3 L0RB 1000 Units on Tape and Reel
3.5 A LP2985AIM5X-3.5 LAIA 3000 Units on Tape and Reel
3.5 A LP2985AIM5-3.5 LAIA 1000 Units on Tape and Reel
3.5 STD LP2985IM5X-3.5 LAIB 3000 Units on Tape and Reel
3.5 STD LP2985IM5-3.5 LAIB 1000 Units on Tape and Reel
3.6 A LP2985AIM5X-3.6 L0SA 3000 Units on Tape and Reel
3.6 A LP2985AIM5-3.6 L0SA 1000 Units on Tape and Reel
3.6 STD LP2985IM5X-3.6 L0SB 3000 Units on Tape and Reel
3.6 STD LP2985IM5-3.6 L0SB 1000 Units on Tape and Reel
3.8 A LP2985AIM5X-3.8 L0YA 3000 Units on Tape and Reel
3.8 A LP2985AIM5-3.8 L0YA 1000 Units on Tape and Reel
3.8 STD LP2985IM5X-3.8 L0YB 3000 Units on Tape and Reel
3.8 STD LP2985IM5-3.8 L0YB 1000 Units on Tape and Reel
4.0 A LP2985AIM5X-4.0 L0TA 3000 Units on Tape and Reel
LP2985
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Ordering Information (Continued)
TABLE 1. Package Marking and Ordering Information (Continued)
Output Voltage
(V)
Grade Order Information
Package
Marking
Supplied as:
5-Lead Small Outline Package (M5)
4.0 A LP2985AIM5-4.0 L0TA 1000 Units on Tape and Reel
4.0 STD LP2985IM5X-4.0 L0TB 3000 Units on Tape and Reel
4.0 STD LP2985IM5-4.0 L0TB 1000 Units on Tape and Reel
4.7 A LP2985AIM5X-4.7 LAJA 3000 Units on Tape and Reel
4.7 A LP2985AIM5-4.7 LAJA 1000 Units on Tape and Reel
4.7 STD LP2985IM5X-4.7 LAJB 3000 Units on Tape and Reel
4.7 STD LP2985IM5-4.7 LAJB 1000 Units on Tape and Reel
4.8 A LP2985AIM5X-4.8 LAKA 3000 Units on Tape and Reel
4.8 A LP2985AIM5-4.8 LAKA 1000 Units on Tape and Reel
4.8 STD LP2985IM5X-4.8 LAKB 3000 Units on Tape and Reel
4.8 STD LP2985IM5-4.8 LAKB 1000 Units on Tape and Reel
5.0 A LP2985AIM5X-5.0 L0UA 3000 Units on Tape and Reel
5.0 A LP2985AIM5-5.0 L0UA 1000 Units on Tape and Reel
5.0 STD LP2985IM5X-5.0 L0UB 3000 Units on Tape and Reel
5.0 STD LP2985IM5-5.0 L0UB 1000 Units on Tape and Reel
micro SMD, 5 Bump Package (BPA05)
2.5 A LP2985AIBP-2.5 250 Units on Tape and Reel
2.5 A LP2985AIBPX-2.5 3000 Units on Tape and Reel
2.5 STD LP2985IBP-2.5 250 Units on Tape and Reel
2.5 STD LP2985IBPX-2.5 3000 Units on Tape and Reel
2.8 A LP2985AIBP-2.8 250 Units on Tape and Reel
2.8 A LP2985AIBPX-2.8 3000 Units on Tape and Reel
2.8 STD LP2985IBP-2.8 250 Units on Tape and Reel
2.8 STD LP2985IBPX-2.8 3000 Units on Tape and Reel
3.3 A LP2985AIBP-3.3 250 Units on Tape and Reel
3.3 A LP2985AIBPX-3.3 3000 Units on Tape and Reel
3.3 STD LP2985IBPX-3.3 250 Units on Tape and Reel
3.3 STD LP2985IBPX-3.3 3000 Units on Tape and Reel
LP2985
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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range −65˚C to +150˚C
Operating Junction Temperature Range −40˚C to +125˚C
Lead Temp. (Soldering, 5 sec.) 260˚C
ESD Rating (Note 2) 2 kV
Power Dissipation (Note 3) Internally Limited
Input Supply Voltage (Survival) −0.3V to +16V
Input Supply Voltage (Operating) 2.5V to +16V
Shutdown Input Voltage (Survival) −0.3V to +16V
Output Voltage (Survival, (Note 4)) −0.3V to +9V
I
OUT
(Survival) Short Circuit
Protected
Input-Output Voltage (Survival, −0.3V to +16V
(Note 5))
Electrical Characteristics
Limits in standard typeface are for TJ= 25˚C. and limits in boldface type apply over the full operating temperature range. Unless otherwise specified: VIN=VO(NOM) + 1V, IL= 1 mA, CIN= 1 µF, C
OUT
= 4.7 µF, V
ON/OFF
= 2V.
Symbol Parameter Conditions Typ
LP2985AI-X.X LP2985I-X.X
Units(Note 6) (Note 6)
Min Max Min Max
∆V
O
Output Voltage
Tolerance
IL= 1 mA −1.0 1.0 −1.5 1.5
%V
NOM
1mA≤IL≤50 mA −1.5 1.5 −2.5 2.5
−2.5 2.5 −3.5 3.5
1mA≤I
L
≤150 mA −2.5 2.5 −3.0 3.0
−3.5 3.5 −4.0 4.0
Output Voltage VO(NOM)+1V ≤ VIN≤ 16V 0.007 0.014 0.014
%/V
Line Regulation 0.032 0.032
V
IN–VO
Dropout Voltage
(Note 7)
IL=0 1 3 3
mV
55
I
L
= 1 mA 7 10 10
15 15
I
L
=10mA 40 60 60
90 90
I
L
= 50 mA 120 150 150
225 225
I
L
= 150 mA 280 350 350
575 575
I
GND
Ground Pin Current IL= 0 65 95 95
µA
125 125
I
L
= 1 mA 75 110 110
170 170
I
L
= 10 mA 120 220 220
400 400
I
L
= 50 mA 350 600 600
1000 1000
I
L
= 150 mA 850 1500 1500
2500 2500
V
ON/OFF
<
0.3V 0.01 0.8 0.8
V
ON/OFF
<
0.15V 0.05 2 2
V
ON/OFF
ON/OFF Input Voltage
(Note 8)
High = O/P ON 1.4 1.6 1.6
V
Low = O/P OFF 0.55 0.15 0.15
I
ON/OFF
ON/OFF Input Current V
ON/OFF
= 0 0.01 −2 −2
µA
V
ON/OFF
=5V 5 15 15
e
n
Output Noise BW = 300 Hz to 50 kHz,
Voltage (RMS) C
OUT
=10µF 30 µV
C
BYPASS
=10nF
LP2985
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Electrical Characteristics (Continued)
Limits in standard typeface are for TJ= 25˚C. and limits in boldface type apply over the full operating temperature range. Unless otherwise specified: VIN=VO(NOM) + 1V, IL= 1 mA, CIN= 1 µF, C
OUT
= 4.7 µF, V
ON/OFF
= 2V.
Symbol Parameter Conditions Typ
LP2985AI-X.X LP2985I-X.X
Units(Note 6) (Note 6)
Min Max Min Max
Ripple Rejection f = 1 kHz, C
BYPASS
=10nF
45 dB
C
OUT
=10µF
I
O
(SC) Short Circuit Current RL= 0 (Steady State)
400 mA
(Note 9)
I
O
(PK) Peak Output Current V
OUT
≥ Vo(NOM) −5% 350 mA
Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the
device outside of its rated operating conditions.
Note 2: The ESD rating of pins 3 and 4 is 1 kV.
Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, T
J
(MAX), the junction-to-ambient thermal resistance, θ
J-A
, and
the ambient temperature, T
A
. The maximum allowable power dissipation at any ambient temperture is calculated using:
Where the value of θ
J-A
for the SOT-23 package is 220˚C/W in a typical PC board mounting and the micro SMD package is 320˚C/W. Exceeding the maximum al-
lowable dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown.
Note 4: If used in a dual-supply system where the regulator load is returned to a negative supply, the LP2985 output must be diode-clamped to ground.
Note 5: The output PNP structure contains a diode between the V
IN
to V
OUT
terminals that is normally reverse-biased. Reversing the polarity from VINto V
OUT
will
turn on this diode.
Note 6: Limits are 100% production tested at 25˚C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control
(SQC) methods. The limits are used to calculate National’s Average Outgoing Quality Level (AOQL).
Note 7: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a 1V differential.
Note 8: The ON/OFF input must be properly driven to prevent possible misoperation. For details, refer to Application Hints.
Note 9: The LP2985 has foldback current limiting which allows a high peak current when V
OUT
>
0.5V, and then reduces the maximum output current as V
OUT
is
forced to ground (see Typical Performance Characteristics curves).
LP2985
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Typical Performance Characteristics Unless otherwise specified: C
IN
= 1µF, C
OUT
= 4.7µF, VIN=
V
OUT
(NOM) +1, TA= 25˚C, ON/OFF pin is tied to VIN.
V
OUT
vs Temperature
DS100140-8
Short-Circuit Current
DS100140-9
Short-Circuit Current
DS100140-10
Short Circuit Current vs Output Voltage
DS100140-11
Ripple Rejection
DS100140-13
Ripple Rejection
DS100140-14
LP2985
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Typical Performance Characteristics Unless otherwise specified: C
IN
= 1µF, C
OUT
= 4.7µF, VIN=
V
OUT
(NOM) +1, TA= 25˚C, ON/OFF pin is tied to VIN. (Continued)
Ripple Rejection
DS100140-15
Ripple Rejection
DS100140-16
Ripple Rejection
DS100140-17
Ripple Rejection
DS100140-18
Ripple Rejection
DS100140-19
Ripple Rejection
DS100140-23
LP2985
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Typical Performance Characteristics Unless otherwise specified: C
IN
= 1µF, C
OUT
= 4.7µF, VIN=
V
OUT
(NOM) +1, TA= 25˚C, ON/OFF pin is tied to VIN. (Continued)
Ripple Rejection
DS100140-22
Output Impedance vs Frequency
DS100140-20
Output Impedance vs Frequency
DS100140-21
Output Noise Density
DS100140-24
Output Noise Density
DS100140-25
Ground Pin vs Load Current
DS100140-26
LP2985
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Typical Performance Characteristics Unless otherwise specified: C
IN
= 1µF, C
OUT
= 4.7µF, VIN=
V
OUT
(NOM) +1, TA= 25˚C, ON/OFF pin is tied to VIN. (Continued)
Dropout Voltage vs Temperature
DS100140-27
Dropout Voltage vs Load Current
DS100140-28
Input Current vs Pin
DS100140-29
GND Pin Current vs Temperature
DS100140-30
Instantaneous Short Circuit Current
DS100140-31
Load Transient Response
DS100140-32
LP2985
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Typical Performance Characteristics Unless otherwise specified: C
IN
= 1µF, C
OUT
= 4.7µF, VIN=
V
OUT
(NOM) +1, TA= 25˚C, ON/OFF pin is tied to VIN. (Continued)
Load Transient Response
DS100140-33
Load Transient Response
DS100140-34
Line Transient Response
DS100140-35
Line Transient Response
DS100140-36
Line Transient Response
DS100140-37
Line Transient Response
DS100140-38
LP2985
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Typical Performance Characteristics Unless otherwise specified: C
IN
= 1µF, C
OUT
= 4.7µF, VIN=
V
OUT
(NOM) +1, TA= 25˚C, ON/OFF pin is tied to VIN. (Continued)
Application Hints
EXTERNAL CAPACITORS
Like any low-dropout regulator, the LP2985 requires external
capacitors for regulator stability. These capacitors must be
correctly selected for good performance.
Input Capacitor
An input capacitor whose capacitance is ≥ 1 µF is required
between the LP2985 input and ground (the amount of capacitance may be increased without limit).
This capacitor must be located a distance of not more than 1
cm from the input pin and returned to a clean analog ground.
Any good quality ceramic, tantalum, or film capacitor may be
used at the input.
Important: Tantalum capacitors can suffer catastrophic failure due to surge current when connected to a
low-impedance source of power (like a battery or 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.
There are no requirements for ESR on the input capacitor,
but tolerance and temperature coefficient must be considered when selecting the capacitor to ensure the capacitance
will be ≥ 1 µF over the entire operating temperature range.
Output Capacitor:
The LP2985 is designed specifically to work with ceramic
output capacitors, utilizing circuitry which allows the regula-
tor to be stable across the entire range of output current with
an output capacitor whose ESR is as low as 5 mΩ.Itmay
also be possible to use Tantalum or film capacitors at the
output, but these are not as attractive for reasons of size and
cost (see next section Capacitor Characteristics).
The output capacitor must meet the requirement for minimum amount of capacitance and also have an ESR (equivalent series resistance) value which is within the stable range.
Curves are provided which show the stable ESR range as a
function of load current (see ESR graph below).
Turn-On Time
DS100140-39
Turn-On Time
DS100140-40
Turn-On Time
DS100140-41
Turn-On Time
DS100140-42
DS100140-7
LP2985
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Application Hints (Continued)
Important: The output capacitor must maintain its ESR
within the stable region over the full operating temperature
range of the application to assure stability.
The LP2985 requires a minimum of 2.2 µF on the output
(output capacitor size can be increased without limit).
It is important to remember that capacitor tolerance and
variation with temperature must be taken into consideration
when selecting an output capacitor so that the minimum required amount of output capacitance is provided over the full
operating temperature range. It should be noted that ceramic
capacitors can exhibit large changes in capacitance with
temperature (see next section,
Capacitor Characteristics
).
The output capacitor must be located not more than 1 cm
from the output pin and returned to a clean analog ground.
Noise Bypass Capacitor:
Connecting a 10 nF capacitor to the Bypass pin significantly
reduces noise on the regulator output. It should be noted that
the capacitor is connected directly to a high-impedance circuit in the bandgap reference.
Because this circuit has only a few microamperes flowing in
it, any significant loading on this node will cause a change in
the regulated output voltage. For this reason, DC leakage
current through the noise bypass capacitor must never exceed 100 nA, and should be kept as low as possible for best
output voltage accuracy.
The types of capacitors best suited for the noise bypass capacitor are ceramic and film. High-quality ceramic capacitors
with either NPO or COG dielectric typically have very low
leakage. 10 nF polypropolene and polycarbonate film capacitors are available in small surface-mount packages and
typically have extremely low leakage current.
CAPACITOR CHARACTERISTICS
The LP2985 was designed to work with ceramic capacitors
on the output to take advantage of the benefits they offer: for
capacitance values in the 2.2 µF to 4.7 µF range, ceramics
are the least expensive and also have the lowest ESR values (which makes them best for eliminating high-frequency
noise). The ESR of a typical 2.2 µF ceramic capacitor is in
the range of 10 mΩ to 20 mΩ, which easily meets the ESR
limits required for stability by the LP2985.
One disadvantage of ceramic capacitors is that their capacitance can vary with temperature. Most large value ceramic
capacitors (≥ 2.2 µF) are manufactured with the Z5U or Y5V
temperature characteristic, which results in the capacitance
dropping by more than 50% as the temperature goes from
25˚C to 85˚C.
This could cause problems if a 2.2 µF capacitor were used
on the output since it will drop down to approximately 1 µF at
high ambient temperatures (which could cause the LM2985
to oscillate). If Z5U or Y5V capacitors are used on the output,
a minimum capacitance value of 4.7 µF must be observed.
Abetter choice for temperature coefficient in ceramic capacitors is X7R, which holds the capacitance within
±
15%. Unfortunately, the larger values of capacitance are not offered
by all manufacturers in the X7R dielectric.
Tantalum:
Tantalum capacitors are less desirable than ceramics for use
as output capacitors because they are more expensive when
comparing equivalent capacitance and voltage ratings in the
1 µF to 4.7 µF range.
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 Tantalumwill
increase about 2:1 as the temperature goes from 25˚C down
to −40˚C, so some guard band must be allowed.
ON/OFF INPUT OPERATION
The LP2985 is shut off by driving the ON/OFF input low, and
turned on by pulling it high. If this feature is not to be used,
the ON/OFF input should be tied to V
IN
to keep the regulator
output on at all times.
To assure proper operation, the signal source used to drive
the ON/OFF input must be able to swing above and below
the specified turn-on/turn-off voltage thresholds listed in the
Electrical Characteristics section under V
ON/OFF
. To prevent
mis-operation, the turn-on (and turn-off) voltage signals applied to the ON/OFF input must have a slew rate which is
≥ 40 mV/µs.
Caution: the regulator output voltage can not be guaranteed
if a slow-moving AC (or DC) signal is applied that is in the
range between the specified turn-on and turn-off voltages
listed under the electrical specification V
ON/OFF
(see Electri-
cal Characteristics).
REVERSE INPUT-OUTPUT VOLTAGE
The PNP power transistor used as the pass element in the
LP2985 has an inherent diode connected between the regulator output and input. During normal operation (where the
input voltage is higher than the output) this diode is
reverse-biased.
However, if the output is pulled above the input, this diode
will turn ON and current will flow into the regulator output. In
such cases, a parasitic SCR can latch which will allow a high
current to flow into V
IN
(and out the ground pin), which can
damage the part.
In any application where the output may be pulled above the
input, an external Schottky diode must be connected from
V
IN
to V
OUT
(cathode on VIN, anode on V
OUT
), to limit the reverse voltage across the LP2985 to 0.3V (see Absolute
Maximum Ratings).
Micro SMD Mounting
The micro SMD package requires specific mounting techniques which are detailed in National Semiconductor Application Note
#
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 the NSMD (non-solder mask defined) type.
For best results during assembly, alignment ordinals on the
PC board may be used to facilitate placement of the micro
SMD device.
Micro SMD Light Sensitivity
Exposing the micro SMD device to direct sunlight will cause
misoperation of the device. Light sources such as Halogen
lamps can also affect electrical performance if brought near
to the device.
The wavelenghts which have the most detrimental effect are
reds and infra-reds, which means that the fluorescent lighting used inside most buildings has very little effect on perfor-
LP2985
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Application Hints (Continued)
mance. A micro SMD test board was brought to within 1 cm
of a fluorescent desk lamp and the effect on the regulated
output voltage was negligible, showing a deviation of less
than 0.1% from nominal.
LP2985
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Physical Dimensions inches (millimeters) unless otherwise noted
5-Lead Small Outline Package (M5)
NS Package Number MF05A
For Order Numbers, refer to
Table 1
in the “Ordering Information” section of this document.
LP2985
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
NOTES: UNLESS OTHERWISE SPECIFIED
1. EPOXY COATING
2. 63Sn/37Pb EUTECTIC BUMP
3. RECOMMEND NON-SOLDER MASK DEFINED LANDING PAD.
4. PIN 1 IS ESTABLISHED BY LOWER LEFT CORNER WITH RESPECT TO TEXT ORIENTATION. REMAINING PINS ARE
NUMBERED COUNTER CLOCKWISE.
5. XXX IN DRAWING NUMBER REPRESENTS PACKAGE SIZE VARIATION WHERE X1 IS PACKAGE WIDTH, X2 IS PACKAGE LENGTH AND X3 IS PACKAGE HEIGHT.
6.NO JEDEC REGISTRATION AS OF AUG.1999.
micro SMD, 5 Bump, Package (BPA05)
NS Package Number BPA05A
For Order Numbers, refer to
Table 1
in the “Ordering Information” section of this document.
The dimensions for X1, X2 and X3 are as given:
X1 = 0.930 +/− 0.030mm
X2 = 1.107 +/− 0.030mm
X3 = 0.850 +/− 0.050mm
LP2985
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Notes
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1. Life support devices or systems are devices or
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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.
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LP2985 Micropower 150 mA Low-Noise Ultra Low-Dropout Regulator
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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