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LM2830, LM2830-Q1

SNVS454E –AUGUST 2006–REVISED DECEMBER 2014

LM2830/-Q1 High-Frequency 1.0-A Load Step-Down DC-DC Regulator

1 Features

3 Description

The LM2830 regulator is

a

monolithic, high-

1

•

LM2830Z-Q1 and LM2830X-Q1 in the SOT-23

Package are Automotive-Grade Products that are

AEC-Q100 Grade 1 Qualified (–40°C to +125°C

Operating Junction Temperature)

frequency, PWM step-down DC-DC converter in a 5-

pin SOT-23 and a 6-Pin WSON package. The device

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

LM2830 regulator is easy to use. The ability to drive

1.0-A loads with an internal 130-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 30

ns, thus supporting exceptionally high frequency

conversion over the entire 3-V to 5.5-V input

operating range down to the minimum output voltage

of 0.6 V. Switching frequency is internally set to 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 standby current of 30

nA. The LM2830 regulator uses current-mode control

and internal compensation to provide high-

•

Space-Saving SOT-23 Package

Input Voltage Range of 3.0 V to 5.5 V

Output Voltage Range of 0.6 V to 4.5 V

1.0-A Output Current

High Switching Frequencies

–

1.6 MHz (LM2830X)

3.0 MHz (LM2830Z)

•

130-mΩ PMOS Switch

0.6-V, 2% Internal Voltage Reference

Internal Soft-Start

Current Mode, PWM Operation

Thermal Shutdown

Overvoltage Protection

2 Applications

performance regulation over

a wide range of

•

Local 5-V to Vcore Step-Down Converters

Core Power in HDDs

Set-Top Boxes

operating conditions. Additional features include

internal soft-start circuitry to reduce inrush current,

pulse-by-pulse current limit, thermal shutdown, and

output overvoltage protection.

USB Powered Devices

DSL Modems

Device Information⁽¹⁾

PART NUMBER

LM2830

LM2830-Q1

PACKAGE

BODY SIZE (NOM)

2.90 mm × 1.60 mm

3.00 mm × 3.00 mm

2.90 mm × 1.60 mm

Automotive

SOT (5)

WSON (6)

SOT (5)

(1) For all available packages, see the orderable addendum at

the end of the datasheet.

Typical Application Circuit

Efficiency vs Load Current

FB

EN

GND

SW

LM2830

R3

C1

L1

V

O

= 3.3V @ 1.0A

V

IN

V

= 5V

IN

R1

R2

D1

C2

C3

1

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.

LM2830, LM2830-Q1

SNVS454E –AUGUST 2006–REVISED DECEMBER 2014

www.ti.com

Table of Contents

7.4 Device Functional Modes........................................ 11

Application and Implementation ........................ 12

8.1 Application Information............................................ 12

8.2 Typical Applications ................................................ 12

Power Supply Recommendations...................... 24

1

2

3

4

5

6

Features.................................................................. 1

Applications ........................................................... 1

Description ............................................................. 1

Revision History..................................................... 2

Pin Configuration and Functions......................... 3

Specifications......................................................... 4

6.1 Absolute Maximum Ratings ...................................... 4

6.2 ESD Ratings: LM2830 .............................................. 4

6.3 ESD Ratings: LM2830-Q1 ........................................ 4

6.4 Recommended Operating Conditions....................... 4

6.5 Thermal Information.................................................. 4

6.6 Electrical Characteristics........................................... 5

6.7 Typical Characteristics.............................................. 6

Detailed Description .............................................. 9

7.1 Overview ................................................................... 9

7.2 Functional Block Diagram ....................................... 10

7.3 Feature Description................................................. 10

8

9

10 Layout................................................................... 24

10.1 Layout Guidelines ................................................. 24

10.2 Layout Example .................................................... 24

10.3 Thermal Considerations........................................ 25

10.4 WSON Package.................................................... 27

11 Device and Documentation Support ................. 28

11.1 Device Support...................................................... 28

11.2 Related Links ........................................................ 28

11.3 Trademarks........................................................... 28

11.4 Electrostatic Discharge Caution............................ 28

11.5 Glossary................................................................ 29

7

12 Mechanical, Packaging, and Orderable

Information ........................................................... 29

4 Revision History

NOTE: Page numbers for previous revisions may differ from page numbers in the current version.

Changes from Revision D (April 2013) to Revision E

Page

•

Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional

Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device

and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1

Changes from Revision C (April 2013) to Revision D

Page

•

Changed layout of National Data Sheet to TI format ........................................................................................................... 23

2

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SNVS454E –AUGUST 2006–REVISED DECEMBER 2014

5 Pin Configuration and Functions

WSON Package

6-Pin

Top View

FB

1

2

6

5

4

EN

GND

DAP

VINA

VIND

SW

3

SOT Package

5-Pins

Top View

FB

3

EN

4

5

2

1

GND

SW

VIN

Pin Functions (5-Pin SOT)

I/O⁽¹⁾

DESCRIPTION

NAME

NO.

SW

1

O

G

I

Output switch. Connect to the inductor and catch diode.

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

possible to this pin.

GND

FB

2

3

4

5

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

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

than VIN + 0.3 V.

EN

I

VIN

I/P

Input supply voltage.

(1) I: Input Pin, O: Output Pin, P: Power Pin, G: Ground Pin

Pin Functions (6-Pin WSON)

I/O⁽¹⁾

DESCRIPTION

NAME

NO.

FB

1

I

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

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

possible to this pin.

GND

2

G

SW

3

4

5

O

Output switch. Connect to the inductor and catch diode.

Power Input supply.

VIND

VINA

I/P

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

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

than VINA + 0.3V.

EN

6

–

I

Die Attach

Pad

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

GND connection.

–

(1) I: Input Pin, O: Output Pin, P: Power Pin, G: Ground Pin

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6 Specifications

6.1 Absolute Maximum Ratings⁽¹⁾⁽²⁾

MIN

–0.5

MAX UNIT

VIN

7

3

V

FB Voltage

EN Voltage

SW Voltage

Junction Temperature⁽³⁾

7

V

7

V

150

°C

T_stg

Storage temperature

–65

(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings

only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended

Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and

specifications.

(3) Thermal shutdown will occur if the junction temperature exceeds the maximum junction temperature of the device.

6.2 ESD Ratings: LM2830

VALUE

±2000

±1000

UNIT

Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins⁽¹⁾

V_(ESD)

Electrostatic discharge

V

Charged device model (CDM), per JEDEC specification JESD22-C101, all

pins⁽²⁾

(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.

(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

6.3 ESD Ratings: LM2830-Q1

VALUE

±2000

±1000

UNIT

Human body model (HBM), per AEC Q100-002⁽¹⁾

WSON corner pins (1, 3, 4, and 6)

V_(ESD)

Electrostatic discharge

V

Charged device model (CDM), per

AEC Q100-011

SOT-23 corner pins (1, 3, 4, and 5)

Other pins

(1) AEC Q100-002 indicates HBM stressing is done in accordance with the ANSI/ESDA/JEDEC JS-001 specification.

6.4 Recommended Operating Conditions

MIN

3

NOM

MAX UNIT

VIN

5.5

V

Junction Temperature

–40

125 °C

6.5 Thermal Information

LM2830,

LM2830

LM2830-Q1

THERMAL METRIC⁽¹⁾

UNIT

DBV

5 PINS

165.2

69.9

NGG

6 PINS

53.9

51.2

28.2

0.6

R_θJA

Junction-to-ambient thermal resistance

Junction-to-case (top) thermal resistance

Junction-to-board thermal resistance

R_θJC(top)

R_θJB

27.3

°C/W

ψ_JT

Junction-to-top characterization parameter

Junction-to-board characterization parameter

Junction-to-case (bottom) thermal resistance

1.8

ψ_JB

26.8

28.3

8.1

R_θJC(bot)

N/A

(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.

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SNVS454E –AUGUST 2006–REVISED DECEMBER 2014

6.6 Electrical Characteristics

VIN = 5 V unless otherwise indicated. Typical values correspond to TJ = 25°C. Minimum and maximum limits apply over

–40°C to 125°C junction temperature range unless otherwise stated.

PARAMETER

Feedback Voltage

ΔV_FB/V_INFeedback Voltage Line Regulation

TEST CONDITIONS

WSON and SOT-23 Package

V_IN= 3 V to 5 V

MIN

TYP

0.600

0.02

0.1

MAX

UNIT

V

V_FB

0.588

0.612

%/V

nA

V

I_B

Feedback Input Bias Current

Undervoltage Lockout

UVLO Hysteresis

100

V_INRising

V_INFalling

2.73

2.3

2.90

UVLO

1.85

0.43

1.6

LM2830-X

1.2

2.25

86%

82%

1.95

3.75

F_SW

Switching Frequency

MHz

LM2830-Z

3.0

LM2830-X

94%

90%

5%

D_MAX

Maximum Duty Cycle

Minimum Duty Cycle

Switch On Resistance

LM2830-Z

LM2830-X

D_MIN

LM2830-Z

7%

WSON Package

SOT-23 Package

V_IN= 3.3 V

150

130

1.75

R_DS(ON)

I_CL

mΩ

A

195

0.4

Switch Current Limit

Shutdown Threshold Voltage

Enable Threshold Voltage

Switch Leakage

1.2

1.8

V_{EN_TH}

V

I_SW

I_EN

100

3.3

4.3

30

nA

mA

nA

°C

Enable Pin Current

Sink/Source

LM2830X V_FB= 0.55

LM2830Z V_FB= 0.55

All Options V_EN= 0 V

5

Quiescent Current (switching)

I_Q

6.5

Quiescent Current (shutdown)

Thermal Shutdown Temperature

T_SD

165

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6.7 Typical Characteristics

All curves taken at VIN = 5.0 V with configuration in typical application circuit shown in Application Information section of this

data sheet. T_J= 25°C, unless otherwise specified.

Figure 1. η vs Load "X" Vin = 5 V, Vo = 1.8 V and 3.3 V

Figure 2. η vs Load "Z" Vin = 5 V, Vo = 3.3 V and 1.8 V

Figure 4. Load Regulation Vin = 3.3 V, Vo = 1.8 V (All

Options)

Figure 3. η vs Load "X and Z" Vin = 3.3 V, Vo = 1.8 V

Figure 5. Load Regulation Vin = 5 V, Vo = 1.8 V (All Options)

Figure 6. Load Regulation Vin = 5 V, Vo = 3.3 V (All Options)

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Typical Characteristics (continued)

All curves taken at VIN = 5.0 V with configuration in typical application circuit shown in Application Information section of this

data sheet. T_J= 25°C, unless otherwise specified.

3.45

1.81

3.35

1.76

3.25

1.71

3.15

1.66

3.05

1.61

2.95

2.85

2.75

1.56

1.51

1.46

1.41

2.65

2.55

1.36

-45 -40 -10 20 50 80 110 125 130

TEMPERATURE (ºC)

Figure 8. Oscillator Frequency vs Temperature - "Z"

Figure 7. Oscillator Frequency vs Temperature - "X"

2000

1950

1900

1850

1800

1750

1700

1650

1600

1550

1500

-45 -40 -10 20 50 80 110 125 130

TEMPERATURE (^oC)

Figure 10. RDSON vs Temperature (WSON Package)

Figure 9. Current Limit vs Temperature Vin = 3.3 V

3.6

3.5

3.4

3.3

3.2

3.1

3.0

-45 -40 -10 20 50 80 110 125 130

TEMPERATURE (ºC)

Figure 11. RDSON vs Temperature (SOT-23 Package)

Figure 12. LM2830X I_Q(Quiescent Current)

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Typical Characteristics (continued)

All curves taken at VIN = 5.0 V with configuration in typical application circuit shown in Application Information section of this

data sheet. T_J= 25°C, unless otherwise specified.

4.6

4.5

4.4

4.3

4.2

4.1

4.0

-45 -40 -10 20 50 80 110 125 130

TEMPERATURE (ºC)

Figure 14. Line Regulation Vo = 1.8 V, Io = 500 mA

Figure 13. LM2830Z I_Q(Quiescent Current)

0.610

0.605

0.600

0.595

0.590

-45 -40 -10 20 50 80 110 125 130

TEMPERATURE (ºC)

Figure 16. Gain vs Frequency (Vin = 5 V, Vo = 1.2 V at 1 A)

Figure 15. V_FBvs Temperature

Figure 17. Phase Plot vs Frequency (Vin = 5 V, Vo = 1.2 V at 1 A)

8

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SNVS454E –AUGUST 2006–REVISED DECEMBER 2014

7 Detailed Description

7.1 Overview

The LM2830 device is a constant frequency PWM buck regulator IC that delivers a 1.0-A load current. The

regulator has a preset switching frequency of 1.6 MHz or 3.0 MHz. This high frequency allows the LM2830

device to operate with small surface-mount capacitors and inductors, resulting in a DC-DC converter that

requires a minimum amount of board space. The LM2830 device is internally compensated, so it is simple to use

and requires few external components. The LM2830 device uses current-mode control to regulate the output

voltage.

The following operating description of the LM2830 device will refer to the Simplified Block Diagram (Functional

Block Diagram) and to the waveforms in Figure 18. The LM2830 device supplies a regulated output voltage by

switching the internal PMOS control switch at constant frequency and variable duty cycle. A switching cycle

begins at the falling edge of the reset pulse generated by the internal oscillator. When this pulse goes low, the

output control logic turns on the internal PMOS control switch. During this on-time, the SW pin voltage (V_SW

)

swings up to approximately V_IN, and the inductor current (I_L) increases with a linear slope. I_Lis measured by the

current sense amplifier, which generates an output proportional to the switch current. The sense signal is

summed with the regulator’s corrective ramp and compared to the error amplifier’s output, which is proportional

to the difference between the feedback voltage and V_REF. When the PWM comparator output goes high, the

output switch turns off until the next switching cycle begins. During the switch off-time, inductor current

discharges through the Schottky catch diode, which forces the SW pin to swing below ground by the forward

voltage (V_D) of the Schottky catch diode. The regulator loop adjusts the duty cycle (D) to maintain a constant

output voltage.

V

SW

D = T /T

ON SW

V

IN

SW

Voltage

T

OFF

ON

0

D

t

V

T

SW

I

L

I

PK

Inductor

Current

0

t

Figure 18. Typical Waveforms

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7.2 Functional Block Diagram

EN

VIN

+

-

I

SENSE

Thermal

ENABLE and UVLO

SHDN

I

LIMIT

OVP

SHDN

-

+

1.15x V

REF

Ramp_Artificial

Control Logic

cv

S

R

Q

I

SENSE

ꢀ

1.6 MHz

ꢀ

+

-

PFET

FB

+

DRIVER

Internal -Comp

SW

V

= 0.6V

REF

SOFT-START

Internal - LDO

GND

7.3 Feature Description

7.3.1 Soft-Start

This function forces V_OUTto increase at a controlled rate during start up. During soft-start, the error reference

voltage of the amplifier ramps from 0 V to its nominal value of 0.6 V in approximately 600 µs. This forces the

regulator output to ramp up in a controlled fashion, which helps reduce inrush current.

7.3.2 Output Overvoltage Protection

The overvoltage comparator compares the FB pin voltage to a voltage that is 15% higher than the internal

reference V_REF. Once the FB pin voltage goes 15% above the internal reference, the internal PMOS control

switch is turned off, which allows the output voltage to decrease toward regulation.

7.3.3 Undervoltage Lockout

Undervoltage lockout (UVLO) prevents the LM2830 device from operating until the input voltage exceeds 2.73 V

(typical). The UVLO threshold has approximately 430 mV of hysteresis, so the part will operate until V_INdrops

below 2.3V (typical). Hysteresis prevents the part from turning off during power up if V_INis nonmonotonic.

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Feature Description (continued)

7.3.4 Current Limit

The LM2830 device uses cycle-by-cycle current limiting to protect the output switch. During each switching cycle,

a current limit comparator detects if the output switch current exceeds 1.75 A (typical), and turns off the switch

until the next switching cycle begins.

7.3.5 Thermal Shutdown

Thermal shutdown limits total power dissipation by turning off the output switch when the IC junction temperature

exceeds 165°C. After thermal shutdown occurs, the output switch does not turn on until the junction temperature

drops to approximately 150°C.

7.4 Device Functional Modes

In normal operational mode, the device will regulate output voltage to the value set with resistive divider.

In addition, this device has an enable (EN) pin that lets the user turn the device on and off by driving this pin high

and low. Default setup is that this pin is connected to V_INthrough pull up resistor (typically 100 kΩ). When enable

pin is low the device is in shutdown mode consuming typically only 30 nA, making it ideal for applications where

low power consumption is desirable.

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8 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component

specification, and TI does not warrant its accuracy or completeness. TI’s customers are

responsible for determining suitability of components for their purposes. Customers should

validate and test their design implementation to confirm system functionality.

8.1 Application Information

The device operates with input voltage in the range of 3.3 V to 5.5 V and provide regulated output voltage up to

1 A of continuous DC load. This device is optimized for high efficiency operation with minimum number of

external components. Also, high switching frequency allows use of small surface-mount components enabling

very small solution size. For component selection, see Detailed Design Procedure.

8.2 Typical Applications

8.2.1 LM2830X Design Vo = 1.2 V at 1.0A

FB

EN

GND

SW

LM2830

R3

C1

L1

V

= 1.2V @ 1.0A

R1

O

V

IN

V

IN

= 5V

D1

C2

R2

Figure 19. LM2830X (1.6 MHz): Vin = 5 V, Vo = 1.2 V at 1.0-A Schematic

8.2.1.1 Design Requirements

This device must be able to operate at any voltage within input voltage range.

Load Current must be defined to properly size the inductor, input and output capacitors. Inductor should be able

to handle full expected load current as well as the peak current generated during load transients and start up.

Inrush current at startup will depend on the output capacitor selection. More details are provided in Detailed

Design Procedure.

Device has an enable (EN) pin that is used to enable and disable the device. This pin is active high and should

not be left floating in application.

8.2.1.2 Detailed Design Procedure

Table 1. Bill of Materials

PART ID

U1

PART VALUE

1.0-A Buck Regulator

22 µF, 6.3 V, X5R

MANUFACTURER

PART NUMBER

LM2830X

TI

TDK

C1, Input Cap

C2, Output Cap

D1, Catch Diode

C3216X5ROJ226M

CRS08

22 µF, 6.3 V, X5R

TDK

0.3 V_fSchottky 1.5 A, 30 V_R

TOSHIBA

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Typical Applications (continued)

Table 1. Bill of Materials (continued)

PART ID

L1

PART VALUE

MANUFACTURER

Coilcraft

PART NUMBER

ME3220-332

3.3 µH, 1.3 A

15.0 kΩ, 1%

100 kΩ, 1%

R2

Vishay

CRCW08051502F

CRCW08051003F

R1

Vishay

R3

Vishay

8.2.1.2.1 Inductor Selection

The Duty Cycle (D) can be approximated quickly using the ratio of output voltage (V_O) to input voltage (V_IN):

V_OUT

D =

V_IN

(1)

The catch diode (D1) forward voltage drop and the voltage drop across the internal PMOS must be included to

calculate a more accurate duty cycle. Calculate D by using the following formula:

V_OUT+ V_D

D =

V_IN+ V_D- V_SW

(2)

V_SWcan be approximated by:

V_SW= I_OUT× R_DSON

(3)

The diode forward drop (V_D) can range from 0.3 V to 0.7 V depending on the quality of the diode. The lower the

V_D, the higher the operating efficiency of the converter. The inductor value determines the output ripple current.

Lower inductor values decrease the size of the inductor, but increase the output ripple current. An increase in the

inductor value will decrease the output ripple current.

One must ensure that the minimum current limit (1.2 A) is not exceeded, so the peak current in the inductor must

be calculated. The peak current (I_LPK) in the inductor is calculated by:

I_LPK= I_OUT+ Δi_L

(4)

'i

L

I

OUT

V

OUT

V

- V

OUT

IN

L

t

DT

T

S

Figure 20. Inductor Current

V_IN- V_OUT

L

2'i_L

=

DT_S

(5)

(6)

In general,

Δi_L= 0.1 × (I_OUT) → 0.2 × (I_OUT

)

If Δi_L= 20% of 1 A, the peak current in the inductor will be 1.2 A. The minimum ensured current limit over all

operating conditions is 1.2 A. One can either reduce Δi_L, or make the engineering judgment that zero margin will

be safe enough. The typical current limit is 1.75 A.

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The LM2830 device operates at frequencies allowing the use of ceramic output capacitors without compromising

transient response. Ceramic capacitors allow higher inductor ripple without significantly increasing output ripple.

See the Output Capacitor for more details on calculating output voltage ripple. Now that the ripple current is

determined, the inductance is calculated by:

DT_S

2'i_L

x (V_IN- V_OUT

)

L =

where

•

T_s= 1/f_s

(7)

When selecting an inductor, make sure that it is capable of supporting the peak output current without saturating.

Inductor saturation will result in a sudden reduction in inductance and prevent the regulator from operating

correctly. Because of the speed of the internal current limit, it is necessary to specify the peak current of the

inductor only required maximum output current. For example, if the designed maximum output current is 1.0 A

and the peak current is 1.25 A, then the inductor should be specified with a saturation current limit of > 1.25 A.

There is no need to specify the saturation or peak current of the inductor at the 1.75-A typical switch current limit.

The difference in inductor size is a factor of 5. Because of the operating frequency of the LM2830 device, ferrite

based inductors are preferred to minimize core losses. This presents little restriction because the variety of

ferrite-based inductors is huge. Lastly, inductors with lower series resistance (R_DCR) will provide better operating

efficiency.

8.2.1.2.2 Input Capacitor

An input capacitor is necessary to ensure that V_INdoes not drop excessively during switching transients. The

primary specifications of the input capacitor are capacitance, voltage, RMS current rating, and ESL (Equivalent

Series Inductance). The recommended input capacitance is 22 µF. The input voltage rating is specifically stated

by the capacitor manufacturer. Make sure to check any recommended deratings and also verify if there is any

significant change in capacitance at the operating input voltage and the operating temperature. The input

capacitor maximum RMS input current rating (I_RMS-IN) must be greater than:

'i²

3

D I_OUT²(1-D) +

I_{RMS_IN}

(8)

Neglecting inductor ripple simplifies the above equation to:

I_{RMS_IN}= I_OUT

x

D(1 - D)

(9)

From Equation 9, it can be shown that maximum RMS capacitor current occurs when D = 0.5. Always calculate

the RMS at the point where the duty cycle D is closest to 0.5. The ESL of an input capacitor is usually

determined by the effective cross sectional area of the current path. A large leaded capacitor will have high ESL

and a 0805 ceramic chip capacitor will have very low ESL. At the operating frequencies of the LM2830 device,

leaded capacitors may have an ESL so large that the resulting impedance (2πfL) will be higher than that required

to provide stable operation. As a result, surface-mount capacitors are strongly recommended.

Sanyo POSCAP, Tantalum or Niobium, Panasonic SP, and multilayer ceramic capacitors (MLCC) are all good

choices for both input and output capacitors and have very low ESL. For MLCCs it is recommended to use X7R

or X5R type capacitors due to their tolerance and temperature characteristics. Consult the capacitor

manufacturer data sheets to see how rated capacitance varies over operating conditions.

8.2.1.2.3 Output Capacitor

The output capacitor is selected based upon the desired output ripple and transient response. The initial current

of a load transient is provided mainly by the output capacitor. The output ripple of the converter is:

1

R_ESR

+

'V_OUT= 'I_L

8 x F_SWx C_OUT

(10)

When using MLCCs, the ESR is typically so low that the capacitive ripple may dominate. When this occurs, the

output ripple will be approximately sinusoidal and 90° phase shifted from the switching action. Given the

availability and quality of MLCCs and the expected output voltage of designs using the LM2830 device, there is

really no need to review any other capacitor technologies. Another benefit of ceramic capacitors is their ability to

bypass high frequency noise. A certain amount of switching edge noise will couple through parasitic

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capacitances in the inductor to the output. A ceramic capacitor will bypass this noise while a tantalum will not.

Because the output capacitor is one of the two external components that control the stability of the regulator

control loop, most applications will require a minimum of 22 µF of output capacitance. Capacitance often, but not

always, can be increased significantly with little detriment to the regulator stability. Like the input capacitor,

recommended multilayer ceramic capacitors are X7R or X5R types.

8.2.1.2.4 Catch Diode

The catch diode (D1) conducts during the switch off-time. A Schottky diode is recommended for its fast switching

times and low forward voltage drop. The catch diode should be chosen so that its current rating is greater than:

I_D1= I_OUT× (1-D)

(11)

The reverse breakdown rating of the diode must be at least the maximum input voltage plus appropriate margin.

To improve efficiency, choose a Schottky diode with a low forward voltage drop.

8.2.1.2.5 Output Voltage

The output voltage is set using Equation 12, where R2 is connected between the FB pin and GND, and R1 is

connected between V_Oand the FB pin. A good value for R2 is 10 kΩ. When designing a unity gain converter (Vo

= 0.6 V), R1 should be between 0 Ω and 100 Ω, and R2 should be equal or greater than 10 kΩ.

V_OUT

x R2

- 1

R1 =

V_REF

V_REF= 0.60 V

(12)

(13)

8.2.1.2.6 Calculating Efficiency, and Junction Temperature

The complete LM2830 DC-DC converter efficiency can be calculated in the following manner.

P_OUT

K =

P_IN

(14)

(15)

Or

P_OUT

K =

P_OUT+ P_LOSS

Calculations for determining the most significant power losses are shown below. Other losses totaling less than

2% are not discussed.

Power loss (P_LOSS) is the sum of two basic types of losses in the converter: switching and conduction.

Conduction losses usually dominate at higher output loads, whereas switching losses remain relatively fixed and

dominate at lower output loads. The first step in determining the losses is to calculate the duty cycle (D):

V_OUT+ V_D

D =

V_IN+ V_D- V_SW

(16)

V_SWis the voltage drop across the internal PFET when it is on, and is equal to:

V_SW= I_OUT× R_DSON

(17)

V_Dis the forward voltage drop across the Schottky catch diode. It can be obtained from the diode manufacturer's

Electrical Characteristics section. If the voltage drop across the inductor (V_DCR) is accounted for, the equation

becomes:

V_OUT+ V_D+ V_DCR

D =

V_IN+ V_D+ V_DCR- V_SW

(18)

The conduction losses in the free-wheeling Schottky diode are calculated as follows:

P_DIODE= V_D× I_OUT× (1-D)

(19)

Often this is the single most significant power loss in the circuit. Care should be taken to choose a Schottky

diode that has a low forward voltage drop.

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Another significant external power loss is the conduction loss in the output inductor. The equation can be

simplified to:

P_IND= I_OUT²× R_DCR

(20)

The conduction loss of the LC2830 device is mainly associated with the internal PFET:

2

'i_L

I_OUT

1

3

_CONDꢀ= (I_OUT²x D)

1 +

x

R_DSON

P

(21)

(22)

If the inductor ripple current is fairly small, the conduction losses can be simplified to:

P_COND= I_OUT²× R_DSON× D

Switching losses are also associated with the internal PFET. They occur during the switch on and off transition

periods, where voltages and currents overlap resulting in power loss. The simplest means to determine this loss

is to empirically measuring the rise and fall times (10% to 90%) of the switch at the switch node.

Switching Power Loss is calculated as follows:

P_SWR= 1/2(V_IN× I_OUT× F_SW× T_RISE

)

(23)

(24)

(25)

P_SWF= 1/2(V_IN× I_OUT× F_SW× T_FALL

P_SW= P_SWR+ P_SWF

)

Another loss is the power required for operation of the internal circuitry:

P_Q= I_Q× V_IN

(26)

I_Qis the quiescent operating current, and is typically around 3.3 mA for the 1.6-MHz frequency option.

Table 2 lists typical application power losses.

Table 2. Power Loss Tabulation

Design Parameter

Value

5.0 V

Design Parameter

Value

3.3 W

V_IN

V_OUT

I_OUT

V_D

3.3 V

P_OUT

1.0A

0.45 V

1.6 MHz

3.3 mA

4 nS

P_DIODE

150 mW

F_SW

I_Q

P_Q

P_SWR

17 mW

6 mW

T_RISE

T_FALL

R_DS(ON)

IND_DCR

D

4 nS

P_SWF

6 mW

150 mΩ

70 mΩ

0.667

88%

P_COND

P_IND

P_LOSS

P_INTERNAL

100 mW

70 mW

345 mW

125 mW

η

ΣP_COND+ P_SW+ P_DIODE+ P_IND+ P_Q= P_LOSS

ΣP_COND+ P_SWF+ P_SWR+ P_Q= P_INTERNAL

P_INTERNAL= 125mW

(27)

(28)

(29)

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8.2.1.3 Application Curves

Figure 21 and Figure 22 show start-up waveforms.

Figure 22. V_IN= 5.0 V, V_OUT= 0.9 V, I_load= 1 A at –40°C

Figure 21. V_IN= 5.0 V, V_OUT= 0.6 V, I_load= 250 mA at 25°C

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8.2.2 LM2830X Design Vo = 0.6 V at 1.0-A

Figure 23 shows typical application circuit for step-down solution from V_IN=5 to V_OUT=0.6 V, 1.0-A load current.

FB

EN

GND

SW

LM2830

R3

C1

L1

V

O

= 0.6V @ 1.0A

R1

V

IN

V

= 5V

IN

D1

C2

R2

Figure 23. LM2830X (1.6 MHz): Vin = 5 V, Vo = 0.6 V at 1.0-A Schematic

Table 3. Bill of Materials

PART ID

PART VALUE

1.0-A Buck Regulator

22 µF, 6.3 V, X5R

0.3 V_fSchottky 1.5 A, 30 V_R

3.3 µH, 1.3 A

MANUFACTURER

PART NUMBER

LM2830X

U1

TI

C1, Input Cap

TDK

C3216X5ROJ226M

CRS08

C2, Output Cap

TDK

D1, Catch Diode

TOSHIBA

Coilcraft

Vishay

L1

R2

R1

R3

ME3220-332

10.0 kΩ, 1%

CRCW08051000F

0 Ω

100 kΩ, 1%

Vishay

CRCW08051003F

18

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8.2.3 LM2830X Design Vo = 3.3 V at 1.0-A

Figure 24 shows typical application circuit for step down solution from V_IN=5 to V_OUT=3.3 V, 1.0-A load current.

FB

EN

GND

SW

LM2830

R3

C1

L1

V

= 3.3V @ 1.0A

R1

O

V

IN

V

IN

= 5V

D1

C2

R2

Figure 24. LM2830X (1.6 MHz): Vin = 5 V, Vo = 3.3 V at 1.0-A Schematic

Table 4. Bill of Materials

PART ID

PART VALUE

1.0-A Buck Regulator

22 µF, 6.3 V, X5R

0.3 V_fSchottky 1.5 A, 30 V_R

2.2 µH, 1.8 A

MANUFACTURER

TI

PART NUMBER

LM2830X

U1

C1, Input Cap

TDK

C3216X5ROJ226M

CRS08

C2, Output Cap

TDK

D1, Catch Diode

TOSHIBA

Coilcraft

Vishay

L1

R2

R1

R3

ME3220-222

10.0 kΩ, 1%

CRCW08051002F

CRCW08054532F

CRCW08051003F

45.3 kΩ, 1%

Vishay

100 kΩ, 1%

Vishay

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8.2.4 LM2830Z Design Vo = 3.3 V at 1.0-A

Figure 25 shows typical application circuit for step down solution from V_IN=5 to V_OUT=3.3 V, 1.0-A load current

when using device version with higher switching frequency.

FB

EN

GND

SW

LM2830

R3

C1

L1

V

= 3.3V @ 1.0A

R1

O

V

IN

V

IN

= 5V

D1

C2

R2

Figure 25. LM2830Z (3 MHz): Vin = 5 V, Vo = 3.3 V at 1.0-A Schematic

Table 5. Bill of Materials

PART ID

PART VALUE

1.0-A Buck Regulator

22 µF, 6.3 V, X5R

0.3 V_fSchottky 1.5 A, 30V_R

1.6 µH, 2.0 A

MANUFACTURER

PART NUMBER

LM2830Z

U1

TI

TDK

C1, Input Cap

C3216X5ROJ226M

CRS08

C2, Output Cap

TDK

D1, Catch Diode

TOSHIBA

TDK

L1

R2

R1

R3

VLCF4018T-1R6N1R7-2

CRCW08051002F

CRCW08054532F

CRCW08051003F

10.0 kΩ, 1%

Vishay

45.3 kΩ, 1%

100 kΩ, 1%

20

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8.2.5 LM2830Z Design Vo = 1.2 V at 1.0-A

Figure 26 shows a typical application circuit for step down solution from V_IN=5 to V_OUT=1.2 V, 1.0-A load current

when using device version with higher switching frequency.

FB

EN

GND

SW

LM2830

R3

C1

L1

V

= 1.2V @ 1.0A

R1

O

V

IN

V

IN

= 5V

D1

C2

R2

Figure 26. LM2830Z (3 MHz): Vin = 5 V, Vo = 1.2 V at 1.0-A Schematic

Table 6. Bill of Materials

PART ID

PART VALUE

1.0-A Buck Regulator

22 µF, 6.3 V, X5R

0.3V_fSchottky 1.5 A, 30V_R

1.6 µH, 2.0 A

MANUFACTURER

PART NUMBER

LM2830Z

U1

TI

TDK

C1, Input Cap

C3216X5ROJ226M

CRS08

C2, Output Cap

TDK

D1, Catch Diode

TOSHIBA

TDK

L1

R2

R1

R3

VLCF4018T-1R6N1R7-2

CRCW08051002F

CRCW08051003F

10.0 kΩ, 1%

Vishay

10.0 kΩ, 1%

100 kΩ, 1%

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8.2.6 LM2830X Dual Converters With Delayed Enabled Design

Figure 27 shows proposed solution with two LM2830 devices. Output of device on top (3.3-V output) is used to

control the enable pin of the lower device, thus ensuring that the second device (1.2-V output) can not turn on

before the output of first device (3.3-V in this example) reaches steady state. Additionally, small POR supervisory

(LP3470) circuit is used to monitor enable voltage for lower device. The RESET pin on POR circuit is open drain

and requires typically 20-kΩ pullup resistor to the monitored voltage.

V

IN

U1

VIND

C1

VINA

R3

L1

V

= 3.3V @ 1.0A

R1

O

SW

EN

D1

C2

R2

LM2830

GND

FB

U3

4

3

2

R6

LP3470M5X-3.08

LP3470

RESET

5

1

V

IN

C7

U2

VIND VINA

C3

L2

V

= 1.2V @ 1.0A

R4

O

SW

LM2830

D2

C4

R5

EN

GND

FB

Figure 27. LM2830X (1.6 MHz): Vin = 5 V, Vo = 1.2 V at 1.0 A and 3.3 V at 1.0-A Schematic

Table 7. Bill of Materials

PART ID

U1, U2

PART VALUE

1.0-A Buck Regulator

Power on Reset

22 µF, 6.3 V, X5R

Trr delay capacitor

0.3 V_fSchottky 1.5 A, 30 V_R

3.3 µH, 1.3 A

MANUFACTURER

PART NUMBER

LM2830X

TI

U3

LP3470M5X-3.08

C3216X5ROJ226M

C1, C3 Input Cap

C2, C4 Output Cap

C7

TDK

D1, D2 Catch Diode

L1, L2

TOSHIBA

Coilcraft

Vishay

CRS08

ME3220-332

R2, R4, R5

R1, R6

10.0 kΩ, 1%

CRCW08051002F

CRCW08054532F

CRCW08051003F

45.3 kΩ, 1%

R3

100 kΩ, 1%

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8.2.7 LM2830X Buck Converter and Voltage Double Circuit With LDO Follower

Figure 28 shows an example where the LM2830 device is used to provide regulated output voltage (3.3 V) as

well as input voltage for an LDO, effectively providing solution with two output voltages.

V

O

= 5V @ 150mA

U2

L2

LDO

D2

C5

C4

C6

U1

C3

L1

LM2830

VIND

SW

V

= 5V

IN

VINA

EN

R1

R2

GND

FB

C1

V

= 3.3V @ 1.0A

O

C2

D1

Figure 28. LM2830X (1.6 MHz): Vin = 5 V, Vo = 3.3 V at 1.0 A and LP2986-5.0 at 150-mA Schematic

Table 8. Bill of Materials

PART ID

PART VALUE

1.0-A Buck Regulator

200-mA LDO

MANUFACTURER

TI

PART NUMBER

LM2830X

U1

U2

TI

LP2986-5.0

C1, Input Cap

22 µF, 6.3 V, X5R

2.2 µF, 6.3 V, X5R

0.3 V_fSchottky 1.5 A, 30 V_R

0.4 V_fSchottky 20 V_R, 500 mA

10 µH, 800 mA

TDK

C3216X5ROJ226M

C1608X5R0J225M

CRS08

C2, Output Cap

TDK

C3 – C6

TDK

D1, Catch Diode

TOSHIBA

ON Semi

CoilCraft

TDK

D2

L2

L1

R2

R1

MBR0520

ME3220-103

3.3 µH, 2.2 A

VLCF5020T-3R3N2R0-1

CRCW08054532F

CRCW08051002F

45.3 kΩ, 1%

Vishay

10.0 kΩ, 1%

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9 Power Supply Recommendations

The LM2830 is designed to operate from an input voltage supply range between 3.0 V and 5.5 V. This input

supply should be able to withstand the maximum input current and maintain a voltage above 3.0 V. If the input

supply is located farther away (more than a few inches) from the LM2830, additional bulk capacitance may be

required in addition to the ceramic bypass capacitors.

10 Layout

10.1 Layout Guidelines

When planning layout there are a few things to consider when trying to achieve a clean, regulated output. The

most important consideration is the close coupling of the GND connections of the input capacitor and the catch

diode D1. These ground ends should be close to one another and be connected to the GND plane with at least

two through-holes. Place these components as close to the IC as possible. Next in importance is the location of

the GND connection of the output capacitor, which should be near the GND connections of CIN and D1.

There should be a continuous ground plane on the bottom layer of a two-layer board except under the switching

node island.

The FB pin is a high-impedance node and care should be taken to make the FB trace short to avoid noise pickup

and inaccurate regulation. The feedback resistors should be placed as close as possible to the IC, with the GND

of R1 placed as close as possible to the GND of the IC. The V_OUTtrace to R2 should be routed away from the

inductor and any other traces that are switching.

High AC currents flow through the V_IN, SW and V_OUTtraces, so they should be as short and wide as possible.

However, making the traces wide increases radiated noise, so the designer must make this trade-off. Radiated

noise can be decreased by choosing a shielded inductor.

The remaining components should also be placed as close as possible to the IC. See Application Note AN-1229

SNVA054 for further considerations and the LM2830 demo board as an example of a four-layer layout.

10.2 Layout Example

Figure 29. Example Schematic

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Layout Example (continued)

Figure 30. PCB Layout Example

10.3 Thermal Considerations

The PCB size, weight of copper used to route traces and ground plane, and number of layers within the PCB can

greatly effect R_θJA. The type and number of thermal vias can also make a large difference in the thermal

impedance. Thermal vias are necessary in most applications. They conduct heat from the surface of the PCB to

the ground plane. Four to six thermal vias should be placed under the exposed pad to the ground plane if the

WSON package is used.

Thermal impedance also depends on the thermal properties of the application operating conditions (Vin, Vo, Io

etc), and the surrounding circuitry.

Silicon Junction Temperature Determination Method 1:

To accurately measure the silicon temperature for a given application, two methods can be used. The first

method requires the user to know the thermal impedance of the silicon junction to top case temperature.

Some clarification needs to be made before we go any further.

R

_θJCis the thermal impedance from all six sides of an IC package to silicon junction.

_ΦJCis the thermal impedance from top case to the silicon junction.

R

In this data sheet we will use R_ΦJCso that it allows the user to measure top case temperature with a small

thermocouple attached to the top case.

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Thermal Considerations (continued)

R_ΦJCis approximately 30°C/Watt for the 6-pin WSON package with the exposed pad. Knowing the internal

dissipation from the efficiency calculation given previously, and the case temperature, which can be empirically

measured on the bench we have:

T_J- T_C

Power

R_)JCꢀ

=

(30)

(31)

Therefore:

T_j= (R_ΦJCx P_LOSS) + T_C

From the previous example:

T_j= (R_ΦJCx P_INTERNAL) + T_C

T_j= 30°C/W x 0.189W + T_C

(32)

(33)

The second method can give a very accurate silicon junction temperature.

The first step is to determine R_θJAof the application. The LM2830 device has over-temperature protection

circuitry. When the silicon temperature reaches 165°C, the device stops switching. The protection circuitry has a

hysteresis of about 15°C. Once the silicon temperature has decreased to approximately 150°C, the device will

start to switch again. Knowing this, the R_θJAfor any application can be characterized during the early stages of

the design one may calculate the R_θJAby placing the PCB circuit into a thermal chamber. Raise the ambient

temperature in the given working application until the circuit enters thermal shutdown. If the SW-pin is monitored,

it will be obvious when the internal PFET stops switching, indicating a junction temperature of 165°C. Knowing

the internal power dissipation from the above methods, the junction temperature, and the ambient temperature

R_θJAcan be determined.

165°- Ta

P_INTERNAL

R_TJAꢀ=

(34)

Once this is determined, the maximum ambient temperature allowed for a desired junction temperature can be

found.

An example of calculating R_θJAfor an application using the Texas Instruments LM2830 WSON demonstration

board is shown below.

The four layer PCB is constructed using FR4 with ½ oz copper traces. The copper ground plane is on the bottom

layer. The ground plane is accessed by two vias. The board measures 3-cm × 3-cm. It was placed in an oven

with no forced airflow. The ambient temperature was raised to 144°C, and at that temperature, the device went

into thermal shutdown.

From the previous example:

P_INTERNAL= 189mW

(35)

(36)

165^oC - 144^oC

= 111^oC/W

R_TJA

=

ꢀ

189 mW

If the junction temperature was to be kept below 125°C, then the ambient temperature could not go above 109°C

T_j- (R_θJAx P_LOSS) = T_A

(37)

(38)

125°C - (111°C/W x 189mW) = 104°C

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10.4 WSON Package

Figure 31. Internal WSON Connection

For certain high-power applications, the PCB land may be modified to a "dog bone" shape (see Figure 32). By

increasing the size of ground plane, and adding thermal vias, the R_θJAfor the application can be reduced.

FB

1

2

6

5

4

EN

GND

VINA

VIND

PLANE

SW

3

Figure 32. 6-Lead WSON PCB "Dog Bone" Layout

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11 Device and Documentation Support

11.1 Device Support

11.1.1 Third-Party Products Disclaimer

TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT

CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES

OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER

ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.

11.1.2 Thermal Definitions

T_J

Chip junction temperature

T_A

Ambient temperature

R_θJC

R_θJA

Thermal resistance from chip junction to device case

Thermal resistance from chip junction to ambient air

Heat in the LM2830 device due to internal power dissipation is removed through conduction and/or convection.

Conduction: Heat transfer occurs through cross sectional areas of material. Depending on the material, the

transfer of heat can be considered to have poor to good thermal conductivity properties (insulator

vs. conductor).

Heat Transfer goes as:

Silicon → package → lead frame → PCB

Convection: Heat transfer is by means of airflow. This could be from a fan or natural convection. Natural

convection occurs when air currents rise from the hot device to cooler air.

Thermal impedance is defined as:

'T

R_Tꢀ=

Power

(39)

Thermal impedance from the silicon junction to the ambient air is defined as:

T_J- T_A

Power

R_TJAꢀ=

(40)

11.2 Related Links

The table below lists quick access links. Categories include technical documents, support and community

resources, tools and software, and quick access to sample or buy.

Table 9. Related Links

TECHNICAL

DOCUMENTS

TOOLS &

SOFTWARE

SUPPORT &

COMMUNITY

PARTS

PRODUCT FOLDER

SAMPLE & BUY

LM2830

Click here

LM2830-Q1

11.3 Trademarks

All trademarks are the property of their respective owners.

11.4 Electrostatic Discharge Caution

These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam

during storage or handling to prevent electrostatic damage to the MOS gates.

28

Submit Documentation Feedback

Product Folder Links: LM2830 LM2830-Q1

LM2830, LM2830-Q1

www.ti.com

SNVS454E –AUGUST 2006–REVISED DECEMBER 2014

11.5 Glossary

SLYZ022 — TI Glossary.

This glossary lists and explains terms, acronyms, and definitions.

12 Mechanical, Packaging, and Orderable Information

The following pages include mechanical, packaging, and orderable information. This information is the most

current data available for the designated devices. This data is subject to change without notice and revision of

this document. For browser-based versions of this data sheet, refer to the left-hand navigation.

Submit Documentation Feedback

29

Product Folder Links: LM2830 LM2830-Q1

PACKAGE MATERIALS INFORMATION

www.ti.com

2-Sep-2015

TAPE AND REEL INFORMATION

*All dimensions are nominal

Device

Package Package Pins

Type Drawing

SPQ

Reel

A0

B0

K0

P1

W

Pin1

Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant

(mm) W1 (mm)

LM2830XMF

SOT-23

DBV

NGG

5

6

1000

3000

1000

250

178.0

8.4

12.4

3.2

3.3

3.2

3.3

1.4

1.0

4.0

8.0

12.0

Q3

Q1

LM2830XMF/NOPB

LM2830XMFX/NOPB

LM2830XQMF/NOPB

LM2830XQMFE/NOPB SOT-23

LM2830XQMFX/NOPB SOT-23

3000

1000

3000

1000

250

LM2830ZMF/NOPB

LM2830ZMFX/NOPB

LM2830ZQMF/NOPB

SOT-23

LM2830ZQMFE/NOPB SOT-23

LM2830ZQMFX/NOPB SOT-23

3000

1000

LM2830ZSD/NOPB

WSON

Pack Materials-Page 1

PACKAGE MATERIALS INFORMATION

www.ti.com

2-Sep-2015

*All dimensions are nominal

Device

Package Type Package Drawing Pins

SPQ

Length (mm) Width (mm) Height (mm)

LM2830XMF

SOT-23

WSON

DBV

NGG

5

6

1000

3000

1000

250

210.0

213.0

185.0

191.0

35.0

55.0

LM2830XMF/NOPB

LM2830XMFX/NOPB

LM2830XQMF/NOPB

LM2830XQMFE/NOPB

LM2830XQMFX/NOPB

LM2830ZMF/NOPB

LM2830ZMFX/NOPB

LM2830ZQMF/NOPB

LM2830ZQMFE/NOPB

LM2830ZQMFX/NOPB

LM2830ZSD/NOPB

3000

1000

3000

1000

250

3000

1000

Pack Materials-Page 2

MECHANICAL DATA

NGG0006A

SDE06A (Rev A)

www.ti.com

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型号：	LM2830XMF
厂家：	TEXAS INSTRUMENTS
描述：	LM2830/-Q1 High-Frequency 1.0-A Load Step-Down DC-DC Regulator
文件：	总37页 (文件大小：1465K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

LM2830XMF [TI]

相关型号：

LM2830XMF/NOPB

LM2830XMF/NOPB

LM2830XMFX

LM2830XMFX/NOPB

LM2830XMFX/NOPB

LM2830XQMF/NOPB

LM2830XQMF/NOPB

LM2830XQMFE/NOPB

LM2830XQMFX/NOPB

LM2830XQMFX/NOPB

LM2830ZMF

LM2830ZMF/NOPB