Fairchild FAN53601 service manual

June 2012

FAN53601 / FAN53611 6MHz 600mA / 1A Synchronous Buck Regulator

Features

 600mA or 1A Output Current Capability  24µA Typical Quiescent Current  6MHz Fixed-Frequency Operation  Best-in-Class Load Transient Response  Best-in-Class Efficiency  2.3V to 5.5V Input Voltage Range  0.8 to 2V Fixed Output Voltage  Low Ripple Light-Load PFM Mode  Forced PWM and External Clock Synchronization  Internal Soft-Start  Input Under-Voltage Lockout (UVLO)  Thermal Shutdown and Overload Protection  Optional Output Discharge  6-Bump WLCSP, 0.4mm Pitch

Applications

 6-Bump WLCSP, 0.4mm Pitch  3G, 4G, WiFi

®

, WiMAX™, and WiBro® Data Cards

 Tablets  DSC, DVC  Netbooks

All trademarks are the property of their respective owners.

®

, Ultra-Mobile PCs

Description

The FAN53601/11 is a 6MHz, step-down switching voltage regulator, available in 600mA or 1A options, that delivers a fixed output from an input voltage supply of 2.3V to 5.5V. Using a proprietary architecture with synchronous rectification, the FAN53601/11 is capable of delivering a peak efficiency of 92%, while maintaining efficiency over 80% at load currents as low as 1mA.

The regulator operates at a nominal fixed frequency of 6MHz, which reduces the value of the external components to as low as 470nH for the output inductor and 4.7µF for the output capacitor. In addition, the Pulse Width Modulation (PWM) modulator can be synchronized to an external frequency source.

At moderate and light loads, Pulse Frequency Modulation (PFM) is used to operate the device in Power-Save Mode with a typical quiescent current of 24µA. Even with such a low quiescent current, the part exhibits excellent transient response during large load swings. At higher loads, the system automatically switches to fixed-frequency control, operating at 6MHz. In Shutdown Mode, the supply current drops below 1µA, reducing power consumption. For applications that require minimum ripple or fixed frequency, PFM Mode can be disabled using the MODE pin.

The FAN53601/11 is available in 6-bump, 0.4mm pitch, Wafer-Level Chip-Scale Package (WLCSP).

MODE

L1

SW

470nH

FB

C

F

OUT

A1

B1

C1

A2

B2

C2

VIN

EN

GND

C

IN

2.2 F

FAN53601 / FAN53611 — 6MHz, 600mA / 1A Synchronous Buck Regulator

Figure 1. Typical Application

Ordering Information

Part Number

FAN53611AUC11X 1.100V 1A Yes

FAN53611UC123X 1.233V 1A No

FAN53601UC182X 1.820V 600mA No

Notes:

1. Other voltage options available on request. Contact a Fairchild representative.

2. All voltage and output current options are available with or without active discharge. Contact a Fairchild representative.

Output

Voltage

Max. Output

(1)

Current

Active

Discharge

(2)

Package

WLCSP-6,

0.4mm Pitch

Temperature

Range

–40 to +85°C

Packing

Tape and

Reel

Pin Configurations

FAN53601 / FAN53611 — 6MHz, 600mA / 1A Synchronous Buck Regulator

Figure 2. Bumps Facing Down Figure 3. Bumps Facing Up

Pin Definitions

Pin # Name Description

MODE. Logic 1 on this pin forces the IC to stay in PWM Mode. A logic 0 allows the IC to

A1 MODE

B1 SW

C1 FB

C2 GND

B2 EN

A2 VIN

automatically switch to PFM during light loads. The regulator also synchronizes its switching frequency to four times the frequency provided on this pin. Do not leave this pin floating.

Switching Node. Connect to output inductor.

Feedback / V

Ground. Power and IC ground. All signals are referenced to this pin.

Enable. The device is in Shutdown Mode when voltage to this pin is <0.4V and enabled when >1.2V.

Do not leave this pin floating.

Input Voltage. Connect to input power source.

. Connect to output voltage.

OUT

FAN53601 / FAN53611 — 6MHz, 600mA / 1A Synchronous Buck Regulator

Absolute Maximum Ratings

Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only.

Symbol Parameter Min. Max. Units

VIN Input Voltage –0.3 7.0 V

VSW Voltage on SW Pin –0.3 VIN + 0.3

V

EN and MODE Pin Voltage –0.3 VIN + 0.3

CTRL

Other Pins –0.3 VIN + 0.3

ESD

Electrostatic Discharge Protection Level

Human Body Model per JESD22-A114 3.5

Charged Device Model per JESD22-C101 1.5

TJ Junction Temperature –40 +150 °C

T

Storage Temperature –65 +150 °C

STG

TL Lead Soldering Temperature, 10 Seconds +260 °C

Note:

3. Lesser of 7V or VIN+0.3V.

(3)

V

kV

Recommended Operating Conditions

The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings.

Symbol Parameter Min. Typ. Max. Units

VCC Supply Voltage Range 2.3 5.5 V

I

OUT

L Inductor 470 nH

CIN Input Capacitor 2.2 µF

C

OUT

TA Operating Ambient Temperature –40 +85 °C

TJ Operating Junction Temperature –40 +125 °C

Output Current for FAN53601 0 600 mA

Output Current for FAN53611 0 1 A

Output Capacitor 1.6 4.7 12.0

μF

Thermal Properties

Junction-to-ambient thermal resistance is a function of application and board layout. This data is measured with four-layer 1s2p boards in accordance to JEDEC standard JESD51. Special attention must be paid to not exceed junction temperature T given ambient temperate T

.

A

J(max)

at a

Symbol Parameter Typical Unit

JA

Junction-to-Ambient Thermal Resistance 150 °C/W

Electrical Characteristics

Minimum and maximum values are at VIN = VEN = 2.3V to 5.5V, V Figure 1, unless otherwise noted. Typical values are at T

= 25°C, VIN = VEN = 3.6V.

A

Symbol Parameter Conditions Min. Typ. Max. Units

Power Supplies

IQ Quiescent Current

I

Shutdown Supply Current EN = GND 0.25 1.00 µA

(SD)

V

Under-Voltage Lockout Threshold Rising VIN 2.15 2.27 V

UVLO

V

Under-Voltage Lockout Hysteresis 200 mV

UVHYST

Logic Inputs: EN and MODE Pins

VIH Enable HIGH-Level Input Voltage 1.2 V

VIL Enable LOW-Level Input Voltage 0.4 V

V

Logic Input Hysteresis Voltage 100 mV

LHYST

IIN Enable Input Leakage Current Pin to VIN or GND 0.01 1.00 µA

Switching and Synchronization

fSW Switching Frequency

f

MODE Synchronization Range

SYNC

(4)

V

Regulation

1.233V

Output Voltage

VO

Accuracy

1.820V

tSS Soft-Start From EN Rising Edge 180 300 µs

Output Driver

No load, Not Switching 24 50 µA

PWM Mode 8 mA

= 3.6V, TA = 25°C 5.4 6.0 6.6 MHz

IN

(4)

Square Wave at MODE Input 1.3 1.5 1.7 MHz

= 0 to 1A 1.207 1.233 1.272 V

I

LOAD

PWM Mode 1.207 1.233 1.259 V

= 0 to 1A 1.784 1.820 1.875 V

I

LOAD

PWM Mode 1.784 1.820 1.856 V

= 0V (AUTO Mode), TA = -40°C to +85°C; circuit of

MODE

FAN53601 / FAN53611 — 6MHz, 600mA / 1A Synchronous Buck Regulator

R

DS(on)

PMOS On Resistance V

NMOS On Resistance VIN = VGS = 3.6V 165

= VGS = 3.6V 175

IN

m

Open-Loop for FAN53601 900 1100 1250 mA

I

PMOS Peak Current Limit

LIM(OL)

R

Output Discharge Resistance EN = GND 230

DIS

T

Thermal Shutdown 150 °C

TSD

T

Thermal Shutdown Hysteresis 15 °C

HYS

Open-Loop for FAN53611 1500 1750 2000 mA



Notes:

4. Limited by the effect of t

minimum (see Operation Description section).

OFF

5. The Electrical Characteristics table reflects open-loop data. Refer to the Operation Description and Typical Characteristics Sections for closed-loop data.

Typical Performance Characteristics

Unless otherwise noted, VIN = VEN = 3.6V, V

= 0V (AUTO Mode), V

MODE

= 1.82V, and TA = 25°C.

OUT

FAN53601 / FAN53611 — 6MHz, 600mA / 1A Synchronous Buck Regulator

95%

90%

85%

Effici ency

80%

75%

70%

0 200 400 600 800 1000

Load Cu rrent (mA)

2.7 VIN

3.6 VIN

4.2 VIN

5.0 VIN

Figure 4. Efficiency vs. Load Current and

Input Voltage, Auto Mode, Dotted for Decreasing Load

90%

88%

86%

84%

82%

80%

78%

76%

Effici ency

74%

72%

70%

68%

66%

64%

0 200 400 600 800 1000

Load Cu rrent (mA)

2.7 VIN

3.6 VIN

4.2 VIN

5.0 VIN

Figure 6. Efficiency vs. Load Current and

Input Voltage, V

= 1.23V, Auto Mode, Dotted for

OUT

Decreasing Load

92%

90%

88%

86%

84%

82%

80%

78%

76%

74%

Effici ency

72%

70%

68%

66%

64%

62%

60%

and Temperature, Auto Mode, Dotted for FPWM

90%

88%

86%

84%

82%

80%

78%

76%

74%

Effici ency

72%

70%

68%

66%

64%

62%

60%

and Temperature, V

- 40C, AUTO

+25C, AUTO

+85C, AUTO

- 40C, PWM

+25C, PWM

+85C, PWM

0 200 400 600 800 1000

Load Cu rrent (mA)

Figure 5. Efficiency vs. Load Current

-40C, AUTO +25C, AUT O +85C, AUT O

-40C, PWM +25C, PW M +85C, PW M

0 200 400 60 0 800 1000

Load Current (mA)

Figure 7. Efficiency vs. Load Current

=1.23V, Auto Mode, Dotted for

OUT

FPWM

3

2

1

0

Output Regulation (%)

-1

-2 0 200 400 600 800 1000

Figure 8. ∆V

(%) vs. Load Current and Input Voltage,

OUT

Normalized to 3.6V

2.7VIN, AUTO

3.6VIN, AUTO

4.2VIN, AUTO

5.0VIN, AUTO

2.7VIN, PWM

3.6VIN, PWM

4.2VIN, PWM

5.0VIN, PWM

Load Current (mA)

, 500mA Load, FPWM, Dotted for

IN

Auto Mode

Figure 9. ∆V

3

2

1

0

Output Regulation (%)

-1

-2 0 200 400 600 800 1000

Load Current (mA)

(%) vs. Load Current and Input Voltage,

V

=1.23V, Normalized to 3.6VIN, 500mA Load, FPWM,

OUT

2.7VIN, AUTO

3.6VIN, AUTO

4.2VIN, AUTO

5.0VIN, AUTO

2.7VIN, PWM

3.6VIN, PWM

4.2VIN, PWM

5.0VIN, PWM

Dotted for Auto Mode