MAX8884Y_10,MAX8884Y_10 pdf中文资料,MAX8884Y_10引脚图,MAX8884Y

19-4418; Rev 1; 1/10

700mA DC-DC Step-Down Converters

with Dual 300mA LDO in 2mm x 2mm CSP

General Description

The MAX8884Y/MAX8884Z step-down converters with

dual low-dropout (LDO) linear regulators are intended to

power low-voltage microprocessors, DSPs, camera and

Wi-Fi modules, or other point of load applications in

portable devices. These ICs feature high efficiency with

small external component size. The step-down converter

output voltage is pin selectable between 1.2V and 1.8V,

and provides guaranteed output current of 700mA. The

2/4MHz hysteretic-PWM control scheme allows for tiny

external components and reduces no-load operating

current to 50µA. Two low quiescent current, low-noise

LDOs operate down to 2.7V supply voltage. Two switch-

ing frequency options are available—MAX8884Y (2MHz)

and MAX8884Z (4MHz)—allowing optimization for small-

est solution size or highest efficiency. Fast switching

allows the use of small ceramic 2.2µF input and output

capacitors while maintaining low ripple voltage. The

MAX8884Y/MAX8884Z have individual enables for each

output, maximizing flexibility.

The MAX8884Y/MAX8884Z are available in a 16-bump,

2mm x 2mm CSP package (0.7mm max height).

Features

o

Step-Down Converter

Pin-Selectable Output Voltage (1.2V/1.8V)

2MHz or 4MHz Switching Frequency

Low-Output Voltage Ripple

700mA Output Drive Capability

Simple Logic ON/OFF Control

Tiny External Components

o

Low-Noise LDOs

2 x 300mA LDO

Pin-Selectable Output Voltage (LDO1)

Low 26µV

RMS

(typ) Output Noise

High 65dB (typ) PSRR

Simple Logic ON/OFF Control

o

Low 0.1µA Shutdown Current

o

2.7V to 5.5V Supply Voltage Range

o

Thermal Shutdown

o

Tiny, 2mm x 2mm x 0.65mm CSP Package (4x4 Grid)

MAX8884Y/MAX8884Z

Ordering Information

PART

MAX8884YEREKE+T

MAX8884ZEREKE+T

PIN-PACKAGE

16 CSP

SWITCHING

FREQUENCY

2MHz

4MHz

Applications

Cell Phones/Smartphones

PDA and Palmtop Computers

Portable MP3 and DVD Players

Digital Cameras, Camcorders

PCMCIA Cards

Handheld Instruments

Note:

All devices are specified over the -40°C to +85°C operat-

ing temperature range.

+Denotes

a lead(Pb)-free/RoHS-compliant package.

T = Tape and reel.

Typical Application Circuit appears at end of data sheet.

Pin Configuration

TOP VIEW

(BUMPS ON BOTTOM)

Typical Operating Circuit

BATT

2.7V TO 5.5V

IN1A

2.2µF

IN1B

LX

2.2µH

2.2µF

FB

BUCK

1.2V/1.8V

MAX8884Y

MAX8884Z

A1

REFBP

B1

LDO2

V

LDO1

UP TO 300mA

A2

AGND

B2

BUCK_EN

C2

SEL

D2

LDO1_EN

A3

NC1

B3

LDO2_EN

C3

IN1B

D3

NC2

A4

PGND

B4

LX

C4

IN1A

D4

FB

BUCK ON/OFF

BUCK_EN

MAX8884Y

MAX8884Z

PGND

REFBP

BUCK/LDO1 VOLTAGE

SELECTION

LDO1 ON/OFF

LDO2 ON/OFF

BATT

2.7V TO 5.5V

SEL

LDO1_EN

LDO2_EN

AGND

LDO1

C1

IN2

D1

IN2

LDO2

V

LDO2

UP TO 300mA

LDO1

CSP

________________________________________________________________

Maxim Integrated Products

1

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

700mA DC-DC Step-Down Converters

with Dual 300mA LDO in 2mm x 2mm CSP

MAX8884Y/MAX8884Z

ABSOLUTE MAXIMUM RATINGS

IN1A, IN1B, IN2, REFBP to AGND ........................-0.3V to +6.0V

FB to PGND ...........................................................-0.3V to +6.0V

SEL, BUCK_EN to AGND...............-0.3V to (V

IN1A

/V

IN1B

+ 0.3V)

LDO1, LDO2, LDO1_EN, LDO2_EN

to AGND.................................................-0.3V to (V

IN2

+ 0.3V)

IN2 to IN1A, IN1B ..................................................-0.3V to +0.3V

AGND to PGND .....................................................-0.3V to +0.3V

IN1A, IN1B, LX Current .....................................................1A

RMS

Continuous Power Dissipation (T

A

= +70°C)

16-Bump CSP (derate 12.5mW/°C above +70°C) ..............1W

Operating Temperature .......................................-40°C to +85°C

Junction Temperature ......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Bump Temperature*.........................................................+260°C

*These

ICs are constructed using a unique set of packaging techniques imposing a limit on the thermal profile used during board level

solder attach and rework. This limit permits only the use of the solder profiles recommended in the industry-standard specification,

JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and Convection reflow. Preheating is required. Hand or wave soldering is not allowed.

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional

operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

(V

IN1A

= V

IN1B

= V

IN2

= V

LDO1_EN

= V

LDO2_EN

= V

BUCK_EN

= 3.6V. T

A

= -40°C to +85°C, typical values are at T

A

= +25°C, unless

otherwise noted.) (Note 1)

PARAMETER

INPUT SUPPLY

Input Voltage

Input Undervoltage Threshold

Shutdown Supply Current

No-Load Supply Current

THERMAL PROTECTION

Thermal Shutdown

LOGIC CONTROL

Logic Input-High Voltage

(BUCK_EN, SEL, LDO1_EN,

LDO2_EN)

Logic Input-Low Voltage

(BUCK_EN, SEL, LDO1_EN,

LDO2_EN)

Logic Input Current (BUCK_EN,

SEL, LDO1_EN, LDO2_EN)

FB

Buck Converter Output Voltage

FB Leakage Current

LX

On-Resistance

p-channel MOSFET switch, I

LX

= -40mA

n-channel MOSFET rectifier, I

LX

= 40mA

0.18

0.15

0.30

0.25

SEL = AGND, I

BUCK

= 0A

V

SEL

= V

IN1A

, I

BUCK

= 0A

V

IN1A

= V

IN1B

= V

IN2

= 5.5V,

V

FB

= 0

T

A

= +25°C

T

A

= +85°C

1.18

1.78

1.22

1.80

0.01

1

1.24

1.85

1

V

µA

2.7V

V

IN1A

= V

IN1B

= V

IN2

5.5V

1.3

V

T

A

rising, 20°C typical hysteresis

+160

°C

V

IN1A

, V

IN1B

, V

IN2

V

IN1A

, V

IN1B

, V

IN2

rising, 180mV typical hysteresis

V

BUCK_EN

= V

LDO1_EN

=

V

LDO2_EN

= 0

V

BUCK_EN

= 0, I

LDO1

= I

LDO2

= 0A

V

LDO1_EN

= V

LDO2_EN

= 0, I

BUCK

= 0A, no switching

T

A

= +25°C

T

A

= +85°C

2.7

2.52

2.63

0.1

140

50

230

80

5.5

2.70

4

V

µA

CONDITIONS

MIN

TYP

MAX

UNITS

2.7V

V

IN1A

= V

IN1B

= V

IN2

5.5V

T

A

= +25°C

T

A

= +85°C

0.01

0.1

0.4

1

V

IL

= 0 or V

IH

= V

IN1A

= 5.5V

µA

2

_______________________________________________________________________________________

700mA DC-DC Step-Down Converters

with Dual 300mA LDO in 2mm x 2mm CSP

ELECTRICAL CHARACTERISTICS (continued)

(V

IN1A

= V

IN1B

= V

IN2

= V

LDO1_EN

= V

LDO2_EN

= V

BUCK_EN

= 3.6V. T

A

= -40°C to +85°C, typical values are at T

A

= +25°C, unless

otherwise noted.) (Note 1)

PARAMETER

LX Leakage Current

CONDITIONS

V

IN1A

= V

IN1B

= V

IN2

= 5.5V,

V

LX

= 0

T

A

= +25°C

T

A

= +85°C

0.8

0.6

MAX8884Y_

MAX8884Z_

MIN

TYP

0.1

1

1.0

0.8

40

60

0.07

0.06

From V

BUCK_EN

rising to V

LX

rising

V

IN2

= 5.5V, I

LDO_

= 1mA;

V

IN2

= 3.4V, I

LDO_

= 100mA

V

IN2

= 5.5V, I

LDO_

= 1mA;

V

IN2

= 3.4V, I

LDO_

= 100mA

V

LDO_

= 0

I

LDO_

= 100mA, T

A

= +25°C (V

LDO_

2.5V)

V

IN2

stepped from 3.5V to 5.5V, I

LDO_

= 100mA

I

LDO_

stepped from 50µA to 200mA

10Hz to 100kHz, V

LDO_

= 1.8V,

C

LDO_

= 2.2µF, I

LDO_

= 30mA

10Hz to 100kHz, V

LDO_

= 1.8V,

C

LDO_

= 2.2µF, I

LDO_

= 30mA

0 < I

LDO_

< 10mA

10mA < I

LDO_

< 200mA

200mA < I

LDO_

< 300mA

V

LDO1_EN

= V

LDO2_EN

= 0

From V

LDO_EN

rising to V

LDO_

output rising

0

I

REFBP

1µA

1.237

SEL = AGND

SEL = IN1_

2.770

300

310

450

70

2.4

25

65

26

0.1

1

2.2

100

150

1.250

0.2

250

1.263

5

µs

V

mV

µF

750

200

1.764

120

1.800

2.800

2.830

250

1.836

1.2

1.0

MAX

1

UNITS

µA

A

mA

µs

MAX8884Y/MAX8884Z

p-Channel MOSFET Peak Current

V

LX

= 0

Limit

n-Channel MOSFET Valley

Current Limit

n-Channel MOSFET

Zero-Crossing Threshold

Minimum On-Time

Minimum Off-Time

Power-Up Delay

LDO1, LDO2

Output Voltage V

LDO1

Output Voltage V

LDO2

Output Current

Current Limit

Dropout Voltage

Line Regulation

Load Regulation

Power-Supply Rejection

V

LDO_

/ V

IN2

Output Noise

Output Capacitor for Stable

Operation

Shutdown Output Impedance

Power-Up Delay

REFBP

REFBP Output Voltage

REFBP Supply Rejection

V

IN2

stepped from 2.55V to 5.5V

V

mA

mV

dB

µV

RMS

Note 1:

All devices are 100% production tested at T

A

= +25°C. Limits over the operating temperature range are guaranteed by

design.

_______________________________________________________________________________________

3

700mA DC-DC Step-Down Converters

with Dual 300mA LDO in 2mm x 2mm CSP

MAX8884Y/MAX8884Z

Typical Operating Characteristics

(V

IN

= V

IN1A

= V

IN1B

= V

IN2

= 3.6V, V

BUCK

= 1.2V, V

LDO1

= 1.8V, V

LDO2

= 2.8V, MAX8884YEVKIT, T

A

= +25°C, unless otherwise noted.)

STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT, V

OUT

= 1.8V

MAX8884Y/Z toc01

STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT, V

OUT

= 1.2V

MAX8884Y/Z toc02

STEP-DOWN CONVERTER NO-LOAD

SUPPLY CURRENT vs. INPUT VOLTAGE

V

BUCK_EN

= V

IN

V

LDO1_EN

= V

LDO2_EN

= 0

MAX8884Y/Z toc03

100

90

80

EFFICIENCY (%)

100

90

80

EFFICIENCY (%)

300

250

SUPPLY CURRENT (µA)

200

V

IN

FALLING

150

100

50

MAX8884Z

0

V

IN

RISING

MAX8884Y

70

60

50

40

30

1

10

MAX8884Y, V

IN

= 3.2V

= 3.6V

= 4.2V

MAX8884Z, V

IN

= 3.2V

= 3.6V

= 4.2V

70

60

50

40

30

MAX8884Y, V

IN

= 3.2V

= 3.6V

= 4.2V

MAX8884Z, V

IN

= 3.2V

= 3.6V

= 4.2V

100

1000

1

10

100

1000

0

1

2

3

4

5

6

LOAD CURRENT (mA)

INPUT VOLTAGE (V)

STEP-DOWN OUTPUT VOLTAGE vs. LOAD

CURRENT (VOLTAGE POSITIONING)

1.8

1.7

OUTPUT VOLTAGE (V)

1.6

1.5

1.4

1.3

1.2

1.1

1.0

1

10

100

1000

SEL = AGND

V

LX

I

LX

SEL = IN1_

MAX8884Y/Z toc04

MAX8884Z STEP-DOWN CONVERTER

LIGHT LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc05

MAX8884Y STEP-DOWN CONVERTER

LIGHT LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc06

1.9

V

OUT

AC-COUPLED

V

OUT

20mV/div

AC-COUPLED

10mV/div

100mA/div

0A

100mA/div

0A

I

LX

2V/div

0V

V

LX

I

LOAD

= 50mA

2V/div

0V

400ns/div

1µs/div

LOAD CURRENT (mA)

MAX8884Z STEP-DOWN CONVERTER

HEAVY LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc07

MAX8884Y STEP-DOWN CONVERTER

HEAVY LOAD SWITCHING WAVEFORMS

MAX8884Y/Z toc08

V

OUT

I

LX

AC-COUPLED

10mV/div

500mA/div

0A

V

OUT

AC-COUPLED

10mV/div

500mA/div

0A

I

LX

V

LX

I

LOAD

= 500mA

200ns/div

2V/div

0V

V

LX

I

LOAD

= 500mA

400ns/div

2V/div

0V

4

_______________________________________________________________________________________

700mA DC-DC Step-Down Converters

with Dual 300mA LDO in 2mm x 2mm CSP

Typical Operating Characteristics (continued)

(V

IN

= V

IN1A

= V

IN1B

= V

IN2

= 3.6V, V

BUCK

= 1.2V, V

LDO1

= 1.8V, V

LDO2

= 2.8V, MAX8884YEVKIT, T

A

= +25°C, unless otherwise noted.)

MAX8884Z STEP-DOWN CONVERTER

SOFT-START WAVEFORMS

MAX8884Y/Z toc09

MAX8884Y/MAX8884Z

MAX8884Y STEP-DOWN CONVERTER

SOFT-START WAVEFORMS

MAX8884Y/Z toc10

V

OUT

1V/div

0V

V

OUT

1V/div

0V

I

IN1

200mA/div

0A

I

IN1

200mA/div

0A

I

LX

500mA/div

0A

I

LX

500mA/div

0A

V

BUCK_EN

40µs/div

2V/div

I

LOAD

= 500mA

0V

V

BUCK_EN

40µs/div

2V/div

I

LOAD

= 500mA

0V

MAX8884Y STEP-DOWN CONVERTER

LINE TRANSIENT RESPONSE

MAX8884Y/Z toc11

MAX8884Z STEP-DOWN CONVERTER

LINE TRANSIENT RESPONSE

MAX8884Y/Z toc12

4V

V

IN

3.5V

V

OUT

4V

1V/div

V

IN

4V

1V/div

3.5V

AC-COUPLED

20mV/div

V

OUT

AC-COUPLED

20mV/div

I

LX

200mA/div

I

LX

200mA/div

I

LOAD

= 500mA

10µs/div

0A

10µs/div

I

LOAD

= 500mA

0A

MAX8884Z STEP-DOWN CONVERTER

LOAD TRANSIENT

MAX8884Y/Z toc13

MAX8884Y STEP-DOWN CONVERTER

LOAD TRANSIENT

MAX8884Y/Z toc14

V

OUT

1.8V DC OFFSET

100mV/div

V

OUT

1.8V DC OFFSET

100mV/div

I

LX

500mA/div

0A

I

LX

500mA/div

0A

500mA/div

500mA

0A

10mA

20µs/div

500mA

500mA/div

I

OUT

10mA

20µs/div

10mA

0A

I

OUT

_______________________________________________________________________________________

5

MAX8884Y_10

MAX8884Y_10概述

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