Maxim MAX8805, MAX8805ZEWEEE+T Datasheet

General Description

The MAX8805Y/MAX8805Z high-frequency step-down
converters are optimized for dynamically powering the
power amplifier (PA) in WCDMA or NCDMA handsets.
The devices integrate a high-efficiency PWM step-down
converter for medium- and low-power transmission, and
a 60mΩ typical bypass FET to power the PA directly
from the battery during high-power transmission. Dual
200mA low-noise, high-PSRR low-dropout regulators
(LDOs) for PA biasing are also integrated.

Two switching frequency options are available—2MHz
(MAX8805Y) and 4MHz (MAX8805Z)—allowing optimiza­tion for smallest 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 feedback network is integrated, further reducing
external component count and total solution size.

The MAX8805Y/MAX8805Z use an analog input driven
by an external DAC to control the output voltage linearly
for continuous PA power adjustment. At high duty
cycle, the MAX8805Y/MAX8805Z automatically switch
to the bypass mode, connecting the input to the output
through a low-impedance (60mΩ typ) MOSFET. The
user can also enable the bypass mode directly through
a logic-control input.

The LDOs in the MAX8805Y/MAX8805Z are designed
for low-noise operation (35µV

RMS

typ). Each LDO is indi-

vidually enabled through its own logic control interface.

The MAX8805Y/MAX8805Z are available in a 16-bump,
2mm x 2mm WLP package (0.7mm max height).

Applications

WCDMA/NCDMA Cellular Handsets

Wireless PDAs

Smartphones

Features

♦ PA Step-Down Converter

7.5µs (typ) Settling Time for 0.8V to 3.4V Output
Voltage Change

Dynamic Output Voltage Setting from 0.4V to

V

BATT

60mΩ pFET and 100% Duty Cycle for Low

Dropout

2MHz or 4MHz Switching Frequency
Low Output-Voltage Ripple
600mA Output Drive Capability
2% Maximum Accuracy
Tiny External Components

♦ Dual Low-Noise LDOs

Low 35µV

RMS

(typ) Output Noise
High 70dB (typ) PSRR
Guaranteed 200mA Output Drive Capability
Individual ON/OFF Control

♦ Low 0.1µA Shutdown Current

♦ 2.7V to 5.5V Supply Voltage Range

♦ Thermal Shutdown

♦ Tiny 2mm x 2mm x 0.7mm WLP Package

(4 x 4 Grid)

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in

2mm x 2mm WLP for WCDMA PA Power

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

IN1A

LX

PAA

1μH

BATT

2.7V TO 5.5V

AGND

PA_EN

REFIN

EN1

EN2

IN2

BATT

2.7V TO 5.5V

PA ON/OFF

ANALOG CONTROL

V

PA

0.4V TO V

BATT

REFBP

IN1B

LDO1 ON/OFF

LDO2 ON/OFF

PAB

LDO2

LDO1

V

LDO2

UP

TO 200mA

PGND

HP

FORCED BYPASS

2.2μF

2.2μF

MAX8805Z

V

LDO1

UP

TO 200mA

Typical Operating Circuit

19-0777; Rev 0; 4/07

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

+

Denotes a lead-free package.

T

= Tape and reel package.

*

xy is the output voltage code (see Table 1 in the Output

Voltages section).

Note: All devices are specified over the -40°C to +85°C operat­ing temperature range.

Pin Configuration appears at end of data sheet.

PART

PIN-

PACKAGE

PKG

CODE

SWI T C H I N G

F R EQ U EN C Y

( M H z)

MAX8805YEWExy+T*

16 WLP-16 W162B2+ 1

2

MAX8805ZEWExy+T*

16 WLP-16 W162B2+ 1

4

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in
2mm x 2mm WLP for WCDMA PA Power

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V

IN1A

= V

IN1B

= V

IN2

= V

PA_EN

= V

EN1

= V

EN2

= 3.6V, V

HP

= 0V, V

REFIN

= 0.9V, TA= -40°C to +85°C. Typical values are at TA =

+25°C, unless otherwise noted.) (Note 1)

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.

IN1A, IN1B, IN2, REFIN, EN2, REFBP to AGND ...-0.3V to +6.0V

PAA, PAB, PA_EN, HP to AGND....-0.3V to (V

IN1A/VIN1B

+ 0.3V)

LDO1, LDO2, EN1 to AGND ......................-0.3V to (V

IN2

+ 0.3V)

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

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

LX Current ......................................................................0.7A

RMS

IN1A/IN1B and PAA/PAB Current .....................................2A

RMS

PAA and PAB Short Circuit to GND or IN...................Continuous

Continuous Power Dissipation (T

A

= +70°C)

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

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

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

Bump Temperature (soldering, reflow) ............................+235°C

PARAMETER CONDITIONS MIN TYP MAX UNITS

INPUT SUPPLY

Input Voltage V

IN1A

, V

IN1B

, V

IN2

2.7 5.5 V

Input Undervoltage Threshold V

IN1A

, V

IN1B

, V

IN2

rising, 180mV typical hysteresis 2.52 2.63 2.70 V

TA = +25°C 0.1 4

Shutdown Supply Current V

PA_EN

= V

EN1

= V

EN2

= 0V

T

A

= +85°C 0.1

µA

V

PA_EN

= 0V, I

LDO1

= I

LDO2

= 0A 150 250

MAX8805Y 3500

V

EN1

= V

EN2

= 0V, IPA = 0A,

switching

MAX8805Z 5000

No-Load Supply Current

V

EN1

= V

EN2

= 0V, VHP = 3.6V 150

µA

THERMAL PROTECTION

Thermal Shutdown TA rising, 20°C typical hysteresis +160 °C

LOGIC CONTROL

PA_EN, EN1, EN2, HP Logic­Input High Voltage

2.7V ≤ V

IN1A

= V

IN1B

= V

IN2

≤ 5.5V 1.4 V

PA_EN, EN1, EN2, HP Logic­Input Low Voltage

2.7V ≤ V

IN1A

= V

IN1B

= V

IN2

≤ 5.5V 0.4 V

TA = +25°C 0.01 1

Logic-Input Current
(PA_EN, EN1, EN2, HP)

V

IL

= 0V or V

IH

= V

IN1A

= 5.5V

T

A

= +85°C 0.1

µA

REFIN

REFIN Common-Mode Range 0.1 2.2 V

REFIN to PA_ Gain (Falling Edge) V

REFIN

= 0.4V, 0.9V, 1.7V, 2.2V 1.96 2.00 2.04 V/V

REFIN Input Resistance 540 kΩ

REFIN
Dual Mode™ Threshold

V

REFIN

rising, 50mV hysteresis

0.45 x
V

IN2

0.465 x
V

IN2

0.48 x
V

IN2

V

Note: This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device

can be exposed to 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.

Dual Mode is a trademark of Maxim Integrated Products, Inc.

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in

2mm x 2mm WLP for WCDMA PA Power

_______________________________________________________________________________________ 3

PARAMETER CONDITIONS MIN TYP MAX UNITS

LX

p-channel MOSFET switch, ILX = -40mA 0.18 0.6

On-Resistance

n-channel MOSFET rectifier, I

LX

= 40mA 0.15 0.6

Ω

TA = +25°C 0.1 5

LX Leakage Current

V

IN1A

= V

IN1B

= V

IN2

= 5.5V,

V

LX

= 0V

T

A

= +85°C 1

µA

p-Channel MOSFET Peak
Current Limit

V

LX

= 0V 0.7 0.9 1.1 A

n-Channel MOSFET Valley
Current Limit

0.5 0.7 0.9 A

Minimum On- and Off-Times 0.1 µs

Power-Up Delay From PA_EN rising to LX rising 150 250 µs

BYPASS

TA = +25°C 0.060 0.1

On-Resistance

p-channel MOSFET bypass,
I

OUT

= -90mA

T

A

= +85°C 0.1

Ω

Bypass Current Limit VPA = 0 0.8 1.2 1.8 A

S tep - D ow n C ur r ent Li m i t i n Byp ass VLX = 0 0.7 0.9 1.1 A

Total Bypass Current Limit VLX = VPA = 0 1.5 2.1 2.9 A

TA = +25°C 0.01 10

Bypass Off-Leakage Current

V

IN1A

= V

IN1B

= V

IN2

= 5.5V,

V

PAA

= V

PAB

= 0V

T

A

= +85°C 1

µA

LDO1

MAX8805YEWEAA+T 1.746 1.8 1.854

MAX8805YEWEBC+T 2.425 2.5 2.575

MAX8805YEWECC+T 2.619 2.7 2.781

MAX8805YEWEDD+T 2.716 2.8 2.884

MAX8805YEWEEE+T 2.765 2.85 2.936

Output Voltage V

LDO1

V

IN2

= 5.5V, I

LDO1

= 1mA;

V

IN2

= 3.4V, I

LDO1

= 100mA

MAX8805YEWEGG+T 2.910 3.0

3.090

V

Output Current 200 mA

Current Limit V

LDO1

= 0V 250 550 750 mA

Dropout Voltage I

LDO1

= 100mA, TA = +25°C (V

LDO1

≥ 2.5V) 70 200 mV

Line Regulation V

IN2

stepped from 3.5V to 5.5V, I

LDO1

= 100mA 2.4 mV

Load Regulation I

LDO1

stepped from 50µA to 200mA 25 mV

Power-Supply Rejection
ΔV

LDO1

/ ΔV

IN2

10Hz to 10kHz, C

LDO1

= 1µF, I

LDO1

= 30mA 70 dB

Output Noise 100Hz to 100kHz, C

LDO1

= 1µF, I

LDO1

= 30mA 35 µV

RMS

0 < I

LDO1

< 10mA 100 nF

Output Capacitor for Stable
Operation

0 < I

LDO1

< 200mA 1 µF

Shutdown Output Impedance V

EN1

= 0V 1 kΩ

ELECTRICAL CHARACTERISTICS (continued)

(V

IN1A

= V

IN1B

= V

IN2

= V

PA_EN

= V

EN1

= V

EN2

= 3.6V, V

HP

= 0V, V

REFIN

= 0.9V, TA= -40°C to +85°C. Typical values are at TA =

+25°C, unless otherwise noted.) (Note 1)

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in
2mm x 2mm WLP for WCDMA PA Power

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(V

IN1A

= V

IN1B

= V

IN2

= V

PA_EN

= V

EN1

= V

EN2

= 3.6V, V

HP

= 0V, V

REFIN

= 0.9V, TA= -40°C to +85°C. Typical values are at TA =

+25°C, unless otherwise noted.) (Note 1)

PARAMETER CONDITIONS MIN TYP MAX UNITS

LDO2

MAX8805YEWEAA+T 1.746 1.8 1.854

MAX8805YEWEAC+T 2.619 2.7 2.781

MAX8805YEWEAD+T 2.716 2.8 2.884

MAX8805YEWEBE+T 2.765 2.85 2.936

Output Voltage V

LDO2

V

IN2

= 5.5V, I

LDO2

= 1mA;

V

IN2

= 3.4V, I

LDO2

= 100mA

MAX8805YEWEGG+T 2.910 3.0

3.090

V

Output Current 200 mA

Current Limit V

LDO2

= 0V 250 550 750 mA

Dropout Voltage I

LDO2

= 100mA, TA = +25°C 70 200 mV

Line Regulation V

IN2

stepped from 3.5V to 5.5V, I

LDO2

= 100mA 2.4 mV

Load Regulation I

LDO2

stepped from 50µA to 200mA 25 mV

Power-Supply Rejection
ΔV

LDO2

/ ΔV

IN2

10Hz to 10kHz, C

LDO2

= 1µF, I

LDO2

= 30mA 70 dB

Output Noise 100Hz to 100kHz, C

LDO2

= 1µF, I

LDO2

= 30mA 35 µV

RMS

0µA < I

LDO2

< 10mA 100 nF

Output Capacitor for Stable
Operation

0µA < I

LDO2

< 200mA 1 µF

Shutdown Output Impedance V

EN2

= 0V 1 kΩ

REFBP

REFBP Output Voltage 0 ≤ I

REFBP

≤ 1µA 1.237 1.250 1.263 V

REFBP Supply Rejection V

IN2

stepped from 2.55V to 5.5V 0.2 5 mV

Note 1: All devices are 100% production tested at TA= +25°C. Limits over the operating temperature range are guaranteed by design.

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in

2mm x 2mm WLP for WCDMA PA Power

_______________________________________________________________________________________

5

Typical Operating Characteristics

(V

IN1A

= V

IN1B

= V

IN2

= 3.6V, VPA= 1.2V, V

LDO1

= 2.85V, V

LDO2

= 2.85V, RPA= 7.5Ω, circuit of Figure 5, TA= +25°C, unless other-

wise noted.)

0

40

20

80

60

120

100

140

0 0.4 0.60.2 0.8 1.0 1.2 1.4 1.6 1.8

BYPASS MODE DROPOUT VOLTAGE

vs. PA LOAD CURRENT

MAX8805Y/Z toc01

PA LOAD CURRENT (A)

BYPASS MODE DROPOUT VOLTAGE (mV)

V

IN1

= 3.2V

V

IN1

= 3.6V

60

70

80

90

100

0.5 1.5 2.5 3.51.0 2.0 3.0 4.0 4.5

PA STEP-DOWN CONVERTER EFFICIENCY

vs. OUTPUT VOLTAGE (MAX8805Z)

MAX8805Y/Z toc02

OUTPUT VOLTAGE (V)

EFFICIENCY (%)

BYPASS MODE

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

RPA = 7.5Ω

60

70

80

90

100

0.5 1.5 2.5 3.51.0 2.0 3.0 4.0 4.5

PA STEP-DOWN CONVERTER EFFICIENCY

vs. OUTPUT VOLTAGE (MAX8805Y)

MAX8805Y/Z toc03

OUTPUT VOLTAGE (V)

EFFICIENCY (%)

BYPASS MODE

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

RPA = 7.5Ω

60

70

80

90

100

0.5 1.5 2.5 3.51.0 2.0 3.0 4.0 4.5

PA STEP-DOWN CONVERTER EFFICIENCY

vs. OUTPUT VOLTAGE (MAX8805Z)

MAX8805Y/Z toc04

OUTPUT VOLTAGE (V)

EFFICIENCY (%)

BYPASS MODE

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

RPA = 10Ω

60

70

80

90

100

0.5 1.5 2.5 3.51.0 2.0 3.0 4.0 4.5

PA STEP-DOWN CONVERTER EFFICIENCY

vs. OUTPUT VOLTAGE (MAX8805Y)

MAX8805Y/Z toc05

OUTPUT VOLTAGE (V)

EFFICIENCY (%)

BYPASS MODE

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

RPA = 10Ω

50

60

80

70

90

100

0200100 300 400 500 600

PA STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT (MAX8805Z)

MAX8805Y/Z toc06

LOAD CURRENT (mA)

EFFICIENCY (%)

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

VPA = 1.8V

50

60

80

70

90

100

0 200100 300 500400 600

PA STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT (MAX8805Y)

MAX8805Y/Z toc07

LOAD CURRENT (mA)

EFFICIENCY (%)

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

VPA = 1.8V

50

60

80

70

90

100

0200100 300 500400 600

PA STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT (MAX8805Z)

MAX8805Y/Z toc08

LOAD CURRENT (mA)

EFFICIENCY (%)

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

VPA = 1.2V

50

60

80

70

90

100

0200100 300 500400 600

PA STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT (MAX8805Y)

MAX8805Y/Z toc09

LOAD CURRENT (mA)

EFFICIENCY (%)

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

VPA = 1.2V

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in
2mm x 2mm WLP for WCDMA PA Power

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(V

IN1A

= V

IN1B

= V

IN2

= 3.6V, VPA= 1.2V, V

LDO1

= 2.85V, V

LDO2

= 2.85V, RPA= 7.5Ω, circuit of Figure 5, TA= +25°C, unless other-

wise noted.)

50

60

80

70

90

100

0 200100 300 500400 600

PA STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT (MAX8805Z)

MAX8805Y/Z toc10

LOAD CURRENT (mA)

EFFICIENCY (%)

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

VPA = 0.6V

50

60

80

70

90

100

0 200100 300 500400 600

PA STEP-DOWN CONVERTER EFFICIENCY

vs. LOAD CURRENT (MAX8805Y)

MAX8805Y/Z toc11

LOAD CURRENT (mA)

EFFICIENCY (%)

V

IN1

= 4.2V

V

IN1

= 3.6V

V

IN1

= 3.2V

VPA = 0.6V

1.25

1.20

1.15

1.10

1.05
0 300100 200 400 500 600

PA STEP-DOWN CONVERTER OUTPUT

VOLTAGE vs. LOAD CURRENT

MAX8805Y/Z toc12

LOAD CURRENT (mA)

OUTPUT VOLTAGE (V)

MAX8805Y

MAX8805Z

0.5

1.5

1.0

2.5

2.0

3.5

3.0

4.0

00.80.4 1.2 1.6 2.0

PA STEP-DOWN CONVERTER OUTPUT

VOLTAGE vs. REFIN VOLTAGE

MAX8805Y/Z toc13

REFIN VOLTAGE (V)

OUTPUT VOLTAGE (V)

-100

-60

-80

0

-20

-40

20

40

80

60

100

0.4 0.6 0.70.5 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5

REFIN vs. REFIN TO OUT GAIN (MAX8805Z)

MAX8805Y/Z toc14

REFIN VOLTAGE (V)

OUTPUT VOLTAGE ERROR (mV)

V

IN1

= 3.2V, NO LOAD

V

IN1

= 4.2V, NO LOAD

-50

-30

-10

10

30

50

0.4 0.6 0.70.5 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5

REFIN vs. REFIN TO OUT GAIN (MAX8805Y)

MAX8805Y/Z toc15

REFIN VOLTAGE (V)

OUTPUT VOLTAGE ERROR (mV)

V

IN1

= 3.2V, NO LOAD

V

IN1

= 4.2V, NO LOAD

400ns/div

PA STEP-DOWN CONVERTER LIGHT-LOAD

SWITCHING WAVEFORMS (MAX8805Z)

V

PA

AC-COUPLED

I

LX

200mA/div

20mV/div

2V/div

MAX8805Y/Z toc16

V

LX

VPA = 1.2V, IPA = 50mA

400ns/div

PA STEP-DOWN CONVERTER LIGHT-LOAD

SWITCHING WAVEFORMS (MAX8805Y)

V

PA

AC-COUPLED

I

LX

200mA/div

20mV/div

2V/div

MAX8805Y/Z toc17

V

LX

VPA = 1.2V, IPA = 50mA

400ns/div

PA STEP-DOWN HEAVY-LOAD

SWITCHING WAVEFORMS (MAX8805Z)

V

PA

AC-COUPLED

I

LX

500mA/div

20mV/div

2V/div

MAX8805Y/Z toc18

V

LX

VPA = 1.2V, IPA = 500mA

MAX8805Y/MAX8805Z

600mA PWM Step-Down Converters in

2mm x 2mm WLP for WCDMA PA Power

_______________________________________________________________________________________

7

400ns/div

PA STEP-DOWN HEAVY-LOAD

SWITCHING WAVEFORMS (MAX8805Y)

V

PA

AC-COUPLED

I

LX

500mA/div

20mV/div

2V/div

MAX8805Y/Z toc19

V

LX

VPA = 1.2V, IPA = 500mA

20μs/div

PA STEP-DOWN SOFT-START

WAVEFORMS (MAX8805Z)

V

PA_EN

V

PA

1V/div

2V/div

500mA/div

MAX8805Y/Z toc20

I

LX

20μs/div

PA STEP-DOWN SOFT-START

WAVEFORMS (MAX8805Y)

V

PA_EN

V

PA

1V/div

2V/div

200mA/div

MAX8805Y/Z toc21

I

LX

Typical Operating Characteristics (continued)

(V

IN1A

= V

IN1B

= V

IN2

= 3.6V, VPA= 1.2V, V

LDO1

= 2.85V, V

LDO2

= 2.85V, RPA= 7.5Ω, circuit of Figure 5, TA= +25°C, unless other-

wise noted.)

_______________________________________________________________________________________

7