National Semiconductor LM2832 Technical data

LM2832 High Frequency 2.0A Load - Step-Down DC-DC Regulator

August 2006

General Description

The LM2832 regulator is a monolithic, high frequency, PWM step-down DC/DC converter in a 6 Pin LLP and a 8 Pin eMSOP package. It provides all the active functions to provide local DC/DC conversion with fast transient response and accurate regulation in the smallest possible PCB area. With a minimum of external components, the LM2832 is easy to use. The ability to drive 2.0A loads with an internal 150 mΩ PMOS switch using state-of-the-art 0.5 µm BiCMOS technology results in the best power density available. The world-class control circuitry allows on-times as low as 30ns, thus supporting exceptionally high frequency conversion over the entire 3V to 5.5V input operating range down to the minimum output voltage of 0.6V. Switching frequency is internally set to 550 kHz, 1.6 MHz, or 3.0 MHz, allowing the use of extremely small surface mount inductors and chip capacitors. Even though the operating frequency is high, efficiencies up to 93% are easy to achieve. External shutdown is included, featuring an ultra-low stand-by current of 30 nA. The LM2832 utilizes current-mode control and internal compensation to provide high-performance regulation over a wide range of operating conditions. Additional features include internal soft-start circuitry to reduce inrush current, pulse-by-pulse current limit, thermal shutdown, and output over-voltage protection.

Typical Application Circuit

Features

n Input voltage range of 3.0V to 5.5V n Output voltage range of 0.6V to 4.5V n 2.0A output current n High Switching Frequencies

1.6MHz (LM2832X)

0.55MHz (LM2832Y)

3.0MHz (LM2832Z)

n 150mΩ PMOS switch n 0.6V, 2% Internal Voltage Reference n Internal soft-start n Current mode, PWM operation n Thermal Shutdown n Over voltage protection

Applications

n Local 5V to Vcore Step-Down Converters n Core Power in HDDs n Set-Top Boxes n USB Powered Devices n DSL Modems

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Connection Diagrams

LM2832

6-Pin LLP

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8-Pin eMSOP

20197502

Ordering Information

Order Number

LM2832XMY

LM2832XMYX 3500 units Tape and Reel

LM2832XSD

LM2832XSDX 4500 units Tape and Reel

LM2832YMY

LM2832YMYX 3500 units Tape and Reel

LM2832YSD

LM2832YSDX 4500 units Tape and Reel

LM2832ZMY

LM2832ZMYX 3500 units Tape and Reel

LM2832ZSD

LM2832ZSDX 4500 units Tape and Reel

NOPB versions available as well

Frequency

Option

1.6MHz

0.55MHz

3MHz

Package Type

eMSOP-8 MUY08A SLBB

LLP-6 SDE06A L196B

eMSOP-8 MUY08A SLCB

LLP-6 SDE06A L197B

eMSOP-8 MUY08A SLDB

LLP-6 SDE06A L198B

NSC Package

Drawing

Top Mark Supplied As

1000 units Tape and Reel

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Pin Descriptions 8-Pin eMSOP

Pin Name Function

1 VIND Power Input supply.

2 VINA Control circuitry supply voltage. Connect VINA to VIND on PC board.

3, 5, 7 GND Signal and power ground pin. Place the bottom resistor of the feedback network as close

as possible to this pin.

4 EN Enable control input. Logic high enables operation. Do not allow this pin to float or be

greater

than VIN + 0.3V.

6 FB Feedback pin. Connect to external resistor divider to set output voltage.

8 SW Output switch. Connect to the inductor and catch diode.

DAP Die Attach Pad Connect to system ground for low thermal impedance, but it cannot be used as a primary

GND connection.

Pin Descriptions 6-Pin LLP

Pin Name Function

1 FB Feedback pin. Connect to external resistor divider to set output voltage.

2 GND Signal and power ground pin. Place the bottom resistor of the feedback network as

close as possible to this pin.

3 SW Output switch. Connect to the inductor and catch diode.

4 VIND Power Input supply.

5 VINA Control circuitry supply voltage. Connect VINA to VIND on PC board.

6 EN Enable control input. Logic high enables operation. Do not allow this pin to float or be

greater than VINA + 0.3V.

DAP Die Attach Pad Connect to system ground for low thermal impedance, but it cannot be used as a

primary GND connection.

LM2832

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Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

LM2832

please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.

Storage Temperature −65˚C to +150˚C

Soldering Information

Infrared or Convection Reflow

(15 sec) 220˚C

VIN -0.5V to 7V

FB Voltage -0.5V to 3V

Operating Ratings

EN Voltage -0.5V to 7V

SW Voltage -0.5V to 7V

ESD Susceptibility 2kV

VIN 3V to 5.5V

Junction Temperature −40˚C to +125˚C

Junction Temperature (Note 2) 150˚C

Electrical Characteristics VIN = 5V unless otherwise indicated under the Conditions column. Limits in

standard type are for T +125˚C. Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm at T

Symbol Parameter Conditions Min Typ Max Units

∆V

UVLO

FB/VIN

Feedback Voltage

Feedback Voltage Line Regulation VIN= 3V to 5V 0.02 %/V

Feedback Input Bias Current 0.1 100 nA

Undervoltage Lockout

UVLO Hysteresis 0.43 V

Switching Frequency

Maximum Duty Cycle

Minimum Duty Cycle

Switch On Resistance

Switch Current Limit VIN= 3.3V 2.4 3.25 A

Shutdown Threshold Voltage 0.4

Enable Threshold Voltage 1.8

Switch Leakage 100 nA

Enable Pin Current Sink/Source 100 nA

Quiescent Current (switching)

MAX

MIN

DS(ON)

EN_TH

Quiescent Current (shutdown) All Options V

= 25˚C only; limits in boldface type apply over the junction temperature (TJ) range of -40˚C to

= 25˚C, and are provided for reference purposes only.

LLP-6 Package 0.588 0.600 0.612

eMSOP-8 Package 0.584 0.600 0.616

Rising 2.73 2.90 V

Falling 1.85 2.3

LM2832-X 1.2 1.6 1.95

LM2832-Z 2.25 3.0 3.75

LM2832-X 86 94

LM2832-Z 82 90

LM2832-X 5

LM2832-Z 7

LLP-6 Package 150

eMSOP-8 Package 155 240

LM2832X V

LM2832Z V

= 0.55 3.3 5

= 0.55 2.8 4.5

= 0.55 4.3 6.5

=0V 30 nA

MHzLM2832-Y 0.4 0.55 0.7

%LM2832-Y 90 96

%LM2832-Y 2

mΩ

mALM2831Y V

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Electrical Characteristics VIN = 5V unless otherwise indicated under the Conditions column. Limits in

standard type are for T +125˚C. Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm at T

Symbol Parameter Conditions Min Typ Max Units

Note 1: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating Range indicates conditions for which the device is intended to be functional, but does not guarantee specfic performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics.

Note 2: Thermal shutdown will occur if the junction temperature exceeds the maximum junction temperature of the device.

Note 3: Applies for packages soldered directly onto a 3” x 3” PC board with 2oz. copper on 4 layers in still air.

Junction to Ambient 0 LFPM Air Flow (Note 3)

Junction to Case (Note 3)

Thermal Shutdown Temperature 165 ˚C

= 25˚C only; limits in boldface type apply over the junction temperature (TJ) range of -40˚C to

= 25˚C, and are provided for reference purposes only. (Continued)

LLP-6 and eMSOP-8

Packages

LLP-6 and eMSOP-8

Packages

˚C/W

LM2832

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Typical Performance Characteristics All curves taken at VIN = 5.0V with configuration in typical ap-

plication circuit shown in Application Information section of this datasheet. T

LM2832

η vs Load "X, Y and Z" Vin = 3.3V, Vo = 1.8V η vs Load "X" Vin = 5V, Vo = 1.8V & 3.3V

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η vs Load - "Y" Vin = 5V, Vo = 3.3V & 1.8V η vs Load "Z" Vin = 5V, Vo = 3.3V & 1.8V

= 25˚C, unless otherwise specified.

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Load Regulation

Vin = 3.3V, Vo = 1.8V (All Options)

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Load Regulation

Vin = 5V, Vo = 1.8V (All Options)

Typical Performance Characteristics All curves taken at VIN = 5.0V with configuration in typical

application circuit shown in Application Information section of this datasheet. T specified. (Continued)

Load Regulation

Vin = 5V, Vo = 3.3V (All Options) Oscillator Frequency vs Temperature - "X"

= 25˚C, unless otherwise

LM2832

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Oscillator Frequency vs Temperature - "Y" Oscillator Frequency vs Temperature - "Z"

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Current Limit vs Temperature

Vin = 3.3V RDSON vs Temperature (LLP-6 Package)

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Typical Performance Characteristics All curves taken at VIN = 5.0V with configuration in typical

application circuit shown in Application Information section of this datasheet. T

LM2832

specified. (Continued)

= 25˚C, unless otherwise

RDSON vs Temperature (eMSOP-8 Package) LM2832X I

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(Quiescent Current)

LM2832Y IQ(Quiescent Current) LM2832Z IQ(Quiescent Current)

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Typical Performance Characteristics All curves taken at VIN = 5.0V with configuration in typical

application circuit shown in Application Information section of this datasheet. T specified. (Continued)

Line Regulation

Vo = 1.8V, Io = 500mA V

= 25˚C, unless otherwise

vs Temperature

LM2832

Gain vs Frequency

(Vin = 5V, Vo = 1.2V

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Phase Plot vs Frequency

1A)

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(Vin = 5V, Vo = 1.2V@1A)

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