National Semiconductor LP38690 Technical data

查询LP38690供应商

LP38690/LP38692
1A Low Dropout CMOS Linear Regulators

Stable with Ceramic Output Capacitors

January 2005

LP38690/LP38692 1A Low Dropout CMOS Linear Regulators

Stable with Ceramic Output Capacitors

General Description

The LP38690/2 low dropout CMOS linear regulators provide
tight output tolerance (2.5% typical), extremely low dropout
voltage (450mV
lent AC performance utilizing ultra low ESR ceramic output
capacitors.

The low thermal resistance of the LLP, SOT-223 and T0-252
packages allow the full operating current to be used even in
high ambient temperature environments.

The use of a PMOS power transistor means that no DC base
drive current is required to bias it allowing ground pin current
to remain below 100 µA regardless of load current, input
voltage, or operating temperature.

Dropout Voltage: 450 mV (typ)
Ground Pin Current: 55 µA (typ) at full load.
Precision Output Voltage: 2.5% (25˚C) accuracy.

@

1A load current, V

= 5V), and excel-

OUT

@

1A (typ. 5V out).

Typical Application Circuits

Features

n 2.5% output accuracy (25˚C)
n Low dropout voltage: 450mV
n Wide input voltage range (2.7V to 10V)
n Precision (trimmed) bandgap reference
n Guaranteed specs for -40˚C to +125˚C
n 1µA off-state quiescent current
n Thermal overload protection
n Foldback current limiting
n T0-252, SOT-223 and 6-Lead LLP packages
n Enable pin (LP38692)

@

1A (typ, 5V out)

Applications

n Hard Disk Drives
n Notebook Computers
n Battery Powered Devices
n Portable Instrumentation

20126601

20126602

Note: * Minimum value required for stability.

**LLP package devices only.

© 2005 National Semiconductor Corporation DS201266 www.national.com

Connection Diagrams

LP38690/LP38692

TO-252, Top View

LP38690DT-X.X

6-Lead LLP, Bottom View

LP38690SD-X.X

Pin Description

PIN DESCRIPTION

V

IN

GND Circuit ground for the regulator. This is connected to the die through the lead frame, and also

SNS Output sense pin allows remote sensing at the load which will eliminate the error in output

V

EN

V

OUT

20126603

20126604

SOT-223, Top View

LP38692MP-X.X

20126605

20126606

6-Lead LLP, Bottom View

LP38692SD-X.X

This is the input supply voltage to the regulator. For LLP devices, both VINpins must be tied
together for full current operation (500mA maximum per pin).

functions as the heat sink when the large ground pad is soldered down to a copper plane.

voltage due to voltage drops caused by the resistance in the traces between the regulator and
the load. This pin must be tied to V

OUT

.

The enable pin allows the part to be turned ON and OFF by pulling this pin high or low.

Regulated output voltage.

Ordering Information

Order Number Package Marking Package Type Package Drawing Supplied As

LP38690SD-1.8 L113B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38690SD-2.5 L114B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38690SD-3.3 L115B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38690SD-5.0 L116B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38690DT-1.8 LP38690DT-1.8 TO-252 TD03B Available Soon

LP38690DT-2.5 LP38690DT-2.5 TO-252 TD03B Available Soon

LP38690DT-3.3 LP38690DT-3.3 TO-252 TD03B Available Soon

LP38690DT-5.0 LP38690DT-5.0 TO-252 TD03B Available Soon

LP38692SD-1.8 L123B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38692SD-2.5 L124B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38692SD-3.3 L125B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38692SD-5.0 L126B 6-Lead LLP SDE06A 1000 Units Tape and Reel

LP38692MP-1.8 LJPB SOT-223 MP05A 1000 Units Tape and Reel

www.national.com 2

Ordering Information (Continued)

Order Number Package Marking Package Type Package Drawing Supplied As

LP38692MP-2.5 LJRB SOT-223 MP05A 1000 Units Tape and Reel

LP38692MP-3.3 LJSB SOT-223 MP05A 1000 Units Tape and Reel

LP38692MP-5.0 LJTB SOT-223 MP05A 1000 Units Tape and Reel

LP38690SDX-1.8 L113B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38690SDX-2.5 L114B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38690SDX-3.3 L115B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38690SDX-5.0 L116B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38690DTX-1.8 LP38690DT-1.8 TO-252 TD03B Available Soon

LP38690DTX-2.5 LP38690DT-2.5 TO-252 TD03B Available Soon

LP38690DTX-3.3 LP38690DT-3.3 TO-252 TD03B Available Soon

LP38690DTX-5.0 LP38690DT-5.0 TO-252 TD03B Available Soon

LP38692SDX-1.8 L123B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38692SDX-2.5 L124B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38692SDX-3.3 L125B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38692SDX-5.0 L126B 6-Lead LLP SDE06A 4500 Units Tape and Reel

LP38692MPX-1.8 LJPB SOT-223 MP05A 2000 Units Tape and Reel

LP38692MPX-2.5 LJRB SOT-223 MP05A 2000 Units Tape and Reel

LP38692MPX-3.3 LJSB SOT-223 MP05A 2000 Units Tape and Reel

LP38692MPX-5.0 LJTB SOT-223 MP05A 2000 Units Tape and Reel

LP38690/LP38692

www.national.com3

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

Lead Temp. (Soldering, 5 seconds) 260˚C

LP38690/LP38692

ESD Rating (Note 3) 2 kV

Power Dissipation (Note 2) Internally Limited

V(max) All pins (with respect to GND) -0.3V to 12V

I

OUT

Internally Limited

Junction Temperature −40˚C to +150˚C

Operating Ratings

VINSupply Voltage 2.7V to 10V

Operating Junction
Temperature Range

−40˚C to +125˚C

Electrical Characteristics Limits in standard typeface are for T

over the full operating temperature range. Unless otherwise specified: V

IN=VOUT

= 25˚C, and limits in boldface type apply

J

+ 1V, CIN=C

OUT

= 10 µF, I

Min/Max limits are guaranteed through testing, statistical correlation, or design.

Symbol Parameter Conditions MIN

TYP

(Note 4)

-2.5 2.5

V

O

∆V

/∆V

O

∆V

/∆I

O

L

V

IN-VOUT

I

Q

I

(MIN) Minimum Load Current VIN-VO≤ 4V 100

L

I

FB

PSRR Ripple Rejection V

T

SD

(HYST) Thermal Shutdown Hysteresis

T

SD

Output Voltage Tolerance

Output Voltage Line Regulation

IN

(Note 6)

Output Voltage Load Regulation
(Note 7)

Dropout Voltage (Note 8)

100 µA<I

+1V≤ VIN≤ 10V

V

O

VO+ 0.5V ≤ VIN≤ 10V

= 25mA

I

L

1mA<I
V

IN=VO

= 1.8V)

(V

O

=1A

I

L

= 2.5V)

(V

O

= 0.1A

I

L

=1A

I

L

(V

= 3.3V)

O

= 0.1A

I

L

=1A

I

L

(V

= 5V)

O

= 0.1A

I

L

=1A

I

L

L

<

L

+1V

<

1A

1A

-5.0 5.0

Quiescent Current VIN≤ 10V, IL=100 µA - 1A 55 100

≤ 0.4V, (LP38692 Only) 0.001 1

EN

IN-VO

IN=VO

>

5V 450

O

<

4V 1500

+ 2V(DC), with 1V(p-p)

Foldback Current Limit VIN-V

V

/ 120Hz Ripple

Thermal Shutdown Activation
(Junction Temp)

(Junction Temp)

0.03 0.1 %/V

1.8 5 %/A

950 1600

80

800

65

650

45

450

55 dB

160

10

= 10mA.

LOAD

MAX Units

%V

OUT

145

1300

110

mV

1000

100
800

µAV

mA

˚C

www.national.com 4

LP38690/LP38692

Electrical Characteristics Limits in standard typeface are for T

over the full operating temperature range. Unless otherwise specified: V

IN=VOUT

= 25˚C, and limits in boldface type apply

J

+ 1V, CIN=C

OUT

= 10 µF, I

LOAD

= 10mA.

Min/Max limits are guaranteed through testing, statistical correlation, or design. (Continued)

Symbol Parameter Conditions MIN

e

n

VO(LEAK) Output Leakage Current VO=VO(NOM) + 1V@10V

V

EN

I

EN

Note 1: Absolute maximum ratings indicate limits beyond which damage to the component may occur. Operating ratings indicate conditions for which the device
is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications, see Electrical Characteristics. Specifications do not
apply when operating the device outside of its rated operating conditions.

Note 2: At elevated temperatures, device power dissipation must be derated based on package thermal resistance and heatsink values (if a heatsink is used). The
junction-to-ambient thermal resistance ( θ
area (less than 0.1 square inch). If one square inch of copper is used as a heat dissipator for the TO-252, the θ
package has a θ
to a copper area of one square inch. The θ
(refer to application note AN-1187). If power disspation causes the junction temperature to exceed specified limits, the device will go into thermal shutdown.

Note 3: ESD is tested using the human body model which is a 100pF capacitor discharged through a 1.5k resistor into each pin.

Note 4: Typical numbers represent the most likely parametric norm for 25˚C operation.

Note 5: If used in a dual-supply system where the regulator load is returned to a negative supply, the output pin must be diode clamped to ground.

Note 6: Output voltage line regulation is defined as the change in output voltage from nominal value resulting from a change in input voltage.

Note 7: Output voltage load regulation is defined as the change in output voltage from nominal value as the load current increases from 1mA to full load.

Note 8: Dropout voltage is defined as the minimum input to output differential required to maintain the output within 100mV of nominal value.

Output Noise BW = 10Hz to 10kHz

= 3.3V

V

O

IN

Enable Voltage (LP38692 Only) Output = OFF 0.4

Output = ON, V

Output = ON, V

Output = ON, V

=4V 1.8

IN

=6V 3.0

IN

= 10V 4.0

IN

Enable Pin Leakage VEN= 0V or 10V, VIN= 10V -1 0.001 1 µA

) for the TO-252 is approximately 90˚C/W for a PC board mounting with the device soldered down to minimum copper

J-A

of approximately 125˚C/W when soldered down to a minimum sized pattern (less than 0.1 square inch) and approximately 70˚C/W when soldered

J-A

values for the LLP package are also dependent on trace area, copper thickness, and the number of thermal vias used

J-A

J-A

TYP

(Note 4)

MAX Units

0.7 µV/

0.5 12 µA

drops to approximately 50˚C/W. The SOT-223

V

www.national.com5