OPA2350UA/2K5G4 - TEXAS INSTRUMENTS

LP2985

LP2985 Micropower 150 mA Low-Noise Ultra Low-Dropout Regulator in SOT-23

and micro SMD Packages Designed for Use with Very Low ESR Output

Capacitors

Literature Number: SNVS018U

LP2985

April 26, 2011

Micropower 150 mA Low-Noise Ultra Low-Dropout

Regulator in SOT-23 and micro SMD Packages

Designed for Use with Very Low ESR Output Capacitors

General Description

The LP2985 is a 150 mA, fixed-output voltage regulator de-

signed 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 specifica-

tions critical to battery-powered designs:

Dropout Voltage: Typically 300 mV @ 150 mA load, and

7 mV @ 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 ca-

pacitor 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

■Ultra low dropout voltage

■Guaranteed 150 mA output current

■Smallest possible size (SOT-23, micro SMD package)

■Requires minimum external components

■Stable with low-ESR output capacitor

■<1 µA quiescent current when shut down

■Low ground pin current at all loads

■Output voltage accuracy 1% (A Grade)

■High peak current capability

■Wide supply voltage range (16V max)

■Low ZOUT: 0.3Ω typical (10 Hz to 1 MHz)

■Overtemperature/overcurrent protection

■−40°C to +125°C junction temperature range

■Custom voltages available

Applications

■Cellular Phone

■Palmtop/Laptop Computer

■Personal Digital Assistant (PDA)

■Camcorder, Personal Stereo, Camera

Block Diagram

10014001

VIP® is a registered trademark of National Semiconductor Corporation.

LP2985 Micropower 150 mA Low-Noise Ultra Low-Dropout Regulator in SOT-23 and micro SMD

Packages

Basic Application Circuit

10014002

*ON/OFF input must be actively terminated. Tie to VIN if 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).

Connection Diagrams

SOT-23, 5-Lead Small Outline Package (M5)

10014003

Top View

See NS Package Number MF05A

micro SMD, 5 Bump Package

10014046

Note: The actual physical placement of the package marking will vary from part

to part. Package marking contains date code and lot traceability information, and

will vary considerably. Package marking does not correlate to device type.

Top View

See NS Package Numbers TPA05 and TLA05

Pin Descriptions

Name Pin Number Function

SOT-23 micro SMD

VIN 1 C3 Input Voltage

GND 2 A1 Common Ground (device substrate)

ON/OFF 3 A3 Logic high enable input

BYPASS 4 B2 Bypass capacitor for low noise operation

VOUT 5 C1 Regulated output voltage

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LP2985

Ordering Information

TABLE 1. Package Marking and Ordering Information

Output Voltage

(V) Grade Order Information Package Marking Supplied as:

For output voltages ≤ 2.0V, refer to LP2985LV datasheet.

SOT-23, 5-Lead Small Outline Package (M5)

2.5

ALP2985AIM5-2.5 LAUA 1000 Units on Tape and Reel

LP2985AIM5X-2.5 LAUA 3000 Units on Tape and Reel

STD LP2985IM5-2.5 LAUB 1000 Units on Tape and Reel

LP2985IM5X-2.5 LAUB 3000 Units on Tape and Reel

2.6 A LP2985AIM5-2.6 LCEA 1000 Units on Tape and Reel

LP2985AIM5X-2.6 LCEA 3000 Units on Tape and Reel

2.7

ALP2985AIM5-2.7 LALA 1000 Units on Tape and Reel

LP2985AIM5X-2.7 LALA 3000 Units on Tape and Reel

STD LP2985IM5-2.7 LALB 1000 Units on Tape and Reel

LP2985IM5X-2.7 LALB 3000 Units on Tape and Reel

2.8

ALP2985AIM5-2.8 L0KA 1000 Units on Tape and Reel

LP2985AIM5X-2.8 L0KA 3000 Units on Tape and Reel

STD LP2985IM5-2.8 L0KB 1000 Units on Tape and Reel

LP2985IM5X-2.8 L0KB 3000 Units on Tape and Reel

2.9

ALP2985AIM5-2.9 LAXA 1000 Units on Tape and Reel

LP2985AIM5X-2.9 LAXA 3000 Units on Tape and Reel

STD LP2985IM5-2.9 LAXB 1000 Units on Tape and Reel

LP2985IM5X-2.9 LAXB 3000 Units on Tape and Reel

3.0

ALP2985AIM5-3.0 L0OA 1000 Units on Tape and Reel

LP2985AIM5X-3.0 L0OA 3000 Units on Tape and Reel

STD LP2985IM5-3.0 L0OB 1000 Units on Tape and Reel

LP2985IM5X-3.0 L0OB 3000 Units on Tape and Reel

3.1

ALP2985AIM5-3.1 L0PA 1000 Units on Tape and Reel

LP2985AIM5X-3.1 L0PA 3000 Units on Tape and Reel

STD LP2985IM5-3.1 L0PB 1000 Units on Tape and Reel

LP2985IM5X-3.1 L0PB 3000 Units on Tape and Reel

3.2 STD LP2985IM5-3.2 L0QB 1000 Units on Tape and Reel

3.3

ALP2985AIM5-3.3 L0RA 1000 Units on Tape and Reel

LP2985AIM5X-3.3 L0RA 3000 Units on Tape and Reel

STD LP2985IM5-3.3 L0RB 1000 Units on Tape and Reel

LP2985IM5X-3.3 L0RB 3000 Units on Tape and Reel

3.5 A LP2985AIM5-3.5 LAIA 1000 Units on Tape and Reel

STD LP2985IM5-3.5 LAIB 1000 Units on Tape and Reel

3.6

ALP2985AIM5-3.6 L0SA 1000 Units on Tape and Reel

LP2985AIM5X-3.6 L0SA 3000 Units on Tape and Reel

STD LP2985IM5-3.6 L0SB 1000 Units on Tape and Reel

LP2985IM5X-3.6 L0SB 3000 Units on Tape and Reel

3.8

ALP2985AIM5-3.8 L0YA 1000 Units on Tape and Reel

LP2985AIM5X-3.8 L0YA 3000 Units on Tape and Reel

STD LP2985IM5-3.8 L0YB 1000 Units on Tape and Reel

LP2985IM5X-3.8 L0YB 3000 Units on Tape and Reel

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LP2985

Output Voltage

(V) Grade Order Information Package Marking Supplied as:

4.0

ALP2985AIM5-4.0 L0TA 1000 Units on Tape and Reel

LP2985AIM5X-4.0 L0TA 3000 Units on Tape and Reel

STD LP2985IM5-4.0 L0TB 1000 Units on Tape and Reel

LP2985IM5X-4.0 L0TB 3000 Units on Tape and Reel

4.5

ALP2985AIM5-4.5 LA7A 1000 Units on Tape and Reel

LP2985AIM5X-4.5 LA7A 3000 Units on Tape and Reel

STD LP2985IM5X-4.5 LA7B 1000 Units on Tape and Reel

LP2985IM5-4.5 LA7B 3000 Units on Tape and Reel

5.0

ALP2985AIM5-5.0 L0UA 1000 Units on Tape and Reel

LP2985AIM5X-5.0 L0UA 3000 Units on Tape and Reel

STD LP2985IM5-5.0 L0UB 1000 Units on Tape and Reel

LP2985IM5X-5.0 L0UB 3000 Units on Tape and Reel

5.7

ALP2985AIM5-5.7 LKTA 1000 Units on Tape and Reel

LP2985AIM5X-5.7 LKTA 3000 Units on Tape and Reel

STD LP2985IM5-5.7 LKTB 1000 Units on Tape and Reel

LP2985IM5X-5.7 LKTB 3000 Units on Tape and Reel

6.1

ALP2985AIM5-6.1 LF6A 1000 Units on Tape and Reel

LP2985AIM5X-6.1 LF6A 3000 Units on Tape and Reel

STD LP2985IM5-6.1 LF6B 1000 Units on Tape and Reel

LP2985IM5X-6.1 LF6B 3000 Units on Tape and Reel

micro SMD, 5 Bump Package (TPA05 - 170 µm ball)

2.5 A LP2985AITPX-2.5 3000 Units on Tape and Reel

STD LP2985ITP-2.5 250 Units on Tape and Reel

2.6

ALP2985AITP-2.6 250 Units on Tape and Reel

LP2985AITPX-2.6 3000 Units on Tape and Reel

STD LP2985ITP-2.6 250 Units on Tape and Reel

LP2985ITPX-2.6 3000 Units on Tape and Reel

2.7

ALP2985AITP-2.7 250 Units on Tape and Reel

LP2985AITPX-2.7 3000 Units on Tape and Reel

STD LP2985ITP-2.7 250 Units on Tape and Reel

LP2985ITPX-2.7 3000 Units on Tape and Reel

2.8

ALP2985AITP-2.8 250 Units on Tape and Reel

LP2985AITPX-2.8 3000 Units on Tape and Reel

STD LP2985ITP-2.8 250 Units on Tape and Reel

LP2985ITPX-2.8 3000 Units on Tape and Reel

2.9

ALP2985AITP-2.9 250 Units on Tape and Reel

LP2985AITPX-2.9 3000 Units on Tape and Reel

STD LP2985ITP-2.9 250 Units on Tape and Reel

LP2985ITPX-2.9 3000 Units on Tape and Reel

3.0

ALP2985AITP-3.0 250 Units on Tape and Reel

LP2985AITPX-3.0 3000 Units on Tape and Reel

STD LP2985ITP-3.0 250 Units on Tape and Reel

LP2985ITPX-3.0 3000 Units on Tape and Reel

3.3

ALP2985AITP-3.3 250 Units on Tape and Reel

LP2985AITPX-3.3 3000 Units on Tape and Reel

STD LP2985ITP-3.3 250 Units on Tape and Reel

LP2985ITPX-3.3 3000 Units on Tape and Reel

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LP2985

Output Voltage

(V) Grade Order Information Package Marking Supplied as:

5.0

ALP2985AITP-5.0 250 Units on Tape and Reel

LP2985AITPX-5.0 3000 Units on Tape and Reel

STD LP2985ITP-5.0 250 Units on Tape and Reel

LP2985ITPX-5.0 3000 Units on Tape and Reel

micro SMD, 5 Bump Package (TLA05 - 300 µm ball)

3.3

ALP2985AITL-3.3 250 Units on Tape and Reel

LP2985AITLX-3.3 3000 Units on Tape and Reel

STD LP2985ITL-3.3 250 Units on Tape and Reel

LP2985ITLX-3.3 3000 Units on Tape and Reel

For LP2985 Ordering and Availability Information see: http://www.national.com/mpf/LP/LP2985.html#Order

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LP2985

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

IOUT (Survival) Short Circuit

Protected

Input-Output Voltage (Survival, −0.3V to +16V

(Note 5))

Electrical Characteristics (Note 10)

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, COUT = 4.7 µF, VON/OFF = 2V.

Symbol Parameter Conditions Typ

LP2985AI-X.X LP2985I-X.X

Units

(Note 6) (Note 6)

Min Max Min Max

ΔVOOutput Voltage

Tolerance

IL = 1 mA −1.0 1.0 −1.5 1.5

%VNOM

1 mA ≤ IL ≤ 50 mA −1.5 1.5 −2.5 2.5

−2.5 2.5 −3.5 3.5

1 mA ≤ IL ≤ 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

VIN–VODropout Voltage

(Note 7)

IL = 0 1 3 3

5 5

IL = 1 mA 7 10 10

15 15

IL = 10 mA 40 60 60

90 90

IL = 50 mA 120 150 150

225 225

IL = 150 mA 280 350 350

575 575

IGND Ground Pin Current IL = 0 65 95 95

µA

125 125

IL = 1 mA 75 110 110

170 170

IL = 10 mA 120 220 220

400 400

IL = 50 mA 350 600 600

1000 1000

IL = 150 mA 850 1500 1500

2500 2500

VON/OFF < 0.3V 0.01 0.8 0.8

VON/OFF < 0.15V 0.05 2 2

VON/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

ION/OFF ON/OFF Input Current VON/OFF = 0 0.01 −2 −2 µA

VON/OFF = 5V 5 15 15

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LP2985

Symbol Parameter Conditions Typ

LP2985AI-X.X LP2985I-X.X

Units

(Note 6) (Note 6)

Min Max Min Max

enOutput Noise BW = 300 Hz to 50 kHz,

Voltage (RMS) COUT = 10 µF 30 µV

CBYPASS = 10 nF

Ripple Rejection f = 1 kHz, CBYPASS = 10 nF

COUT = 10 µF

IO(SC) Short Circuit Current RL = 0 (Steady State) 400 mA

(Note 9)

IO(PK) Peak Output Current VOUT ≥ 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 for the SOT-23 package, or pins 5 and 2 for the micro SMD package, is 1 kV.

Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal resistance, θJ-

A, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperture is calculated using:

Where the value of θJ-A for the SOT-23 package is 220°C/W in a typical PC board mounting and the micro SMD package is 225°C/W. Exceeding the maximum

allowable dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown.

Note 4: For 12V option, output voltage survival: -0.3 to +16V. 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 VIN to VOUT terminals that is normally reverse-biased. Reversing the polarity from VIN to VOUT

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 VOUT > 0.5V, and then reduces the maximum output current as VOUT is

forced to ground (see Typical Performance Characteristics curves).

Note 10: Exposing the micro SMD device to direct sunlight will cause misoperation. See Application Hints for additional information.

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LP2985

Typical Performance Characteristics Unless otherwise specified: CIN = 1µF, COUT = 4.7µF, VIN = VOUT

(NOM) +1, TA = 25°C, ON/OFF pin is tied to VIN.

VOUT vs Temperature

10014008

Short-Circuit Current

10014009

Short-Circuit Current

10014010

Short Circuit Current vs Output Voltage

10014011

Ripple Rejection

10014013

Ripple Rejection

10014014

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LP2985

Ripple Rejection

10014015

Ripple Rejection

10014016

Ripple Rejection

10014017

Ripple Rejection

10014018

Ripple Rejection

10014019

Ripple Rejection

10014023

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LP2985

Ripple Rejection

10014022

Output Impedance vs Frequency

10014020

Output Impedance vs Frequency

10014021

Output Noise Density

10014024

Output Noise Density

10014025

Ground Pin vs Load Current

10014026

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LP2985

Dropout Voltage vs Temperature

10014027

Input Current vs Pin

10014029

GND Pin Current vs Temperature

10014030

Instantaneous Short Circuit Current

10014031

Load Transient Response

10014032

Load Transient Response

10014033

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LP2985

Load Transient Response

10014034

Line Transient Response

10014035

Line Transient Response

10014036

Line Transient Response

10014037

Line Transient Response

10014038

Turn-On Time

10014039

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LP2985

Turn-On Time

10014040

Turn-On Time

10014041

Turn-On Time

10014042

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LP2985

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 capac-

itance 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 fail-

ure 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 out-

put capacitors, utilizing circuitry which allows the regulator to

be stable across the entire range of output current with an

output capacitor whose ESR is as low as 5 mΩ. It may 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 se-

ries 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).

10014007

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 (out-

put capacitor size can be increased without limit).

It is important to remember that capacitor tolerance and vari-

ation 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 oper-

ating temperature range. It should be noted that ceramic

capacitors can exhibit large changes in capacitance with tem-

perature (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 ex-

ceed 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 ca-

pacitor 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 capac-

itors are available in small surface-mount packages and typ-

ically 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 capaci-

tance 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 os-

cillate). If Z5U or Y5V capacitors are used on the output, a

minimum capacitance value of 4.7 µF must be observed.

A better choice for temperature coefficient in ceramic capac-

itors is X7R, which holds the capacitance within ±15%. Un-

fortunately, 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 ca-

pacitor 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.

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LP2985

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 VIN 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 Elec-

trical Characteristics section under VON/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 list-

ed under the electrical specification VON/OFF (see Electrical

Characteristics).

REVERSE INPUT-OUTPUT VOLTAGE

The PNP power transistor used as the pass element in the

LP2985 has an inherent diode connected between the regu-

lator output and input. During normal operation (where the

input voltage is higher than the output) this diode is reverse-

biased.

10014054

FIGURE 1. Reverse Current Path

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 cur-

rent to flow into VIN (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

VIN to VOUT (cathode on VIN, anode on VOUT), to limit the re-

verse voltage across the LP2985 to 0.3V (see Absolute Max-

imum Ratings).

10014055

FIGURE 2. Reverse Current Protection

MICRO SMD MOUNTING

The micro SMD package requires specific mounting tech-

niques which are detailed in National Semiconductor Appli-

cation 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-

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.

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LP2985

Physical Dimensions inches (millimeters) unless otherwise noted

SOT-23, 5-Lead Small Outline Package (M5)

NS Package Number MF05A.

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LP2985

NOTES: UNLESS OTHERWISE SPECIFIED

1. EPOXY COATING

2. RECOMMEND NON-SOLDER MASK DEFINED LANDING PAD.

3. PIN 1 IS ESTABLISHED BY LOWER LEFT CORNER WITH RESPECT TO TEXT ORIENTATION. REMAINING PINS ARE NUMBERED COUNTER CLOCK-

WISE.

4. XXX IN DRAWING NUMBER REPRESENTS PACKAGE SIZE VARIATION WHERE X1 IS PACKAGE WIDTH, X2 IS PACKAGE LENGTH AND X3 IS PACK-

AGE HEIGHT.

5.NO JEDEC REGISTRATION AS OF AUG.1999.

micro SMD, 5 Bump, Package (TPA05 - 170 µm ball)

NS Package Number TPA05

The dimensions for X1, X2 and X3 are as given:

X1 = 0.930 +/− 0.030mm

X2 = 1.107 +/− 0.030mm

X3 = 0.500 +/− 0.075mm

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LP2985

NOTES: UNLESS OTHERWISE SPECIFIED

1. EPOXY COATING

2. RECOMMEND NON-SOLDER MASK DEFINED LANDING PAD.

3. PIN 1 IS ESTABLISHED BY LOWER LEFT CORNER WITH RESPECT TO TEXT ORIENTATION. REMAINING PINS ARE NUMBERED COUNTER CLOCK-

WISE.

4. XXX IN DRAWING NUMBER REPRESENTS PACKAGE SIZE VARIATION WHERE X1 IS PACKAGE WIDTH, X2 IS PACKAGE LENGTH AND X3 IS PACK-

AGE HEIGHT.

5.NO JEDEC REGISTRATION AS OF AUG.1999.

micro SMD, 5 Bump, Package (TLA05 - 300 µm ball)

NS Package Number TLA05

The dimensions for X1, X2 and X3 are as given:

X1 = 1.031 +/− 0.030mm

X2 = 1.412 +/− 0.030mm

X3 = 0.600 +/− 0.075mm

www.national.com 18

LP2985

Notes

19 www.national.com

LP2985

Notes

LP2985 Micropower 150 mA Low-Noise Ultra Low-Dropout Regulator in SOT-23 and micro SMD

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