Fairchild FAN2001, FAN2002 service manual

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FAN2001/FAN2002 1A High-Efficiency Step-Down DC-DC Converter

April 2005

FAN2001/FAN2002
1A High-Efficiency Step-Down DC-DC Converter

Features

96% Efficiency, Synchronous Operation

Adjustable Output Voltage Options from 0.8V to V

2.5V to 5.5V Input Voltage Range

Up to 1A Output Current

Fixed Frequency 1.3MHz PWM Operation

High Efficiency Power Save Mode

100% Duty Cycle Low Dropout Operation

Soft Start

Output Over-Voltage Protection

Dynamic Output Voltage Positioning

A Quiescent Current

Thermal Shutdown and Short Circuit Protection

Pb-Free 3x3mm 6-Lead MLP Package

Applications

Pocket PCs, PDAs

Cell Phones

Battery-Powered Portable Devices

Digital Cameras

Hard Disk Drives

Set-Top-Boxes

Point-of-Load Power

Notebook Computers

Communications Equipment

Description

Designed for use in battery-powered applications, the FAN2001/

IN

FAN2002 is a high-efficiency, low-noise synchronous PWM cur­rent mode and Pulse Skip (Power Save) mode DC-DC con­verter. It can provide up to 1A of output current over a wide input
range from 2.5V to 5.5V. The output voltage can be externally
adjusted over a wide range of 0.8V to 5.5V by means of an
external voltage divider.

At moderate and light loads, pulse skipping modulation is used.
Dynamic voltage positioning is applied, and the output voltage is
shifted 0.8% above nominal value for increased headroom dur­ing load transients. At higher loads the system automatically
switches over to current mode PWM control, operating at 1.3
MHz. A current mode control loop with fast transient response
ensures excellent line and load regulation. To achieve high effi­ciency and ensure long battery life, the quiescent current is
reduced to 25µA in Power Save mode, and the supply current
drops below 1µA in shut-down mode. The FAN2001/FAN2002 is
available in a 3x3mm 6-lead MLP package.

Typical Application

V

IN

C

IN

10µF

FAN2001/FAN2002 Rev. 1.0.2

©2005 Fairchild Semiconductor Corporation

PGND

EN

1

P1

2

GND)

(A

3

FAN2001

SW

6

3.3µH

5

NC

FB

4

R1

R2

5KΩ

10KΩ

V

OUT

1.2V (1A)

C

OUT

2 x 10µF

V

OUT

1.2V (1A)

R1

R2

5K

Ω

2 x 10µF

10K

Ω

L1

3.3µH

FB

PGND

SW

1

P1

2

(A

GND)

3

EN

6

V

IN

5

PV

IN

4

10µF

FAN2002

Figure 1. Typical Application

1

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Pin Assignment

FAN2001/FAN2002 1A High-Efficiency Step-Down DC-DC Converter

Top View

V

1

IN

P1

PGND

2

(AGND)

3

EN FB

SW

6

5

NC

4

FB

1

P1

PGND

2

(AGND)

3

SW PV

EN

6

5

V

IN

4

IN

FAN2001 FAN2002

3x3mm 6-Lead MLP

Figure 2. Pin Assignment

Pin Description

FAN2001 (3x3mm 6-Lead MLP)

Pin No. Pin Name Pin Description

P1 AGND Analog Ground. P1 must be soldered to the PCB ground.

1V

2 PGND Power Ground. This pin is connected to the internal MOSFET switches. This pin must be

3ENEnable Input. Logic high enables the chip and logic low disables the chip, reducing the supply

4 FB Feedback Input. Adjustable voltage option, connect this pin to the resistor divider.

5NCNo Connection Pin.

6SWSwitching Node. This pin is connected to the internal MOSFET switches.

IN

Supply Voltage Input.

externally connected to AGND.

current to less than 1µA. Do not float this pin.

FAN2002 (3x3mm 6-Lead MLP)

Pin No. Pin Name Pin Description

P1 AGND Analog Ground. P1 must be soldered to the PCB ground.

1FBFeedback Input. Adjustable voltage option, connect this pin to the resistor divider.

2 PGND Power Ground. This pin is connected to the internal MOSFET switches. This pin must be exter-

3SWSwitching Node. This pin is connected to the internal MOSFET switches.

4 PV

5V

6ENEnable Input. Logic high enables the chip and logic low disables the chip, reducing the supply

IN

nally connected to AGND.

Supply Voltage Input. This pin is connected to the internal MOSFET switches.

IN

Supply Voltage Input.

current to less than 1µA. Do not float this pin.

FAN2001/FAN2002 Rev. 1.0.2

2

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(

µ

FAN2001/FAN2002 1A High-Efficiency Step-Down DC-DC Converter

Absolute Maximum Ratings

(Note1)

Parameter Min Max Unit

V

, PV

IN

IN

Voltage On Any Other Pin -0.3 V

Lead Soldering Temperature (10 seconds) 260 °C

Junction Temperature 150 °C

Storage Temperature -65 150 °C

Thermal Resistance-Junction to Tab

Electrostatic Discharge Protection (ESD) Level (Note 3) HBM 4 kV

,

θ

)

3x3mm 6-lead MLP (Note 2)

JC

CDM 1

-0.3 7 V

IN

8 °C/W

V

Recommended Operating Conditions

Parameter Min Typ Max Unit

Supply Voltage Range 2.5 5.5 V

Output Voltage Range, Adjustable Version 0.8 V

Output Current 1A

Inductor (Note 4) 3.3

Input Capacitor (Note 4) 10 µF

Output Capacitor (Note 4) 2 x 10 µF

Operating Ambient Temperature Range -40 +85 °C

Operating Junction Temperature Range -40 +125 °C

IN

V

H

Notes:

1. Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional
operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure
to absolute maximum rating conditions for extended periods may affect device reliability. Absolute maximum ratings apply individually only, not in
combination. Unless otherwise specified, all other voltages are referenced to AGND.

2. Junction to ambient thermal resistance, θ
via used, diameter of via used, available copper surface, and attached heat sink characteristics.

3. Using Mil Std. 883E, method 3015.7(Human Body Model) and EIA/JESD22C101-A (Charge Device Model).

4. Refer to the applications section for further details.

, is a strong function of PCB material, board thickness, thickness and number of copper planes, number of

JA

FAN2001/FAN2002 Rev. 1.0.2

3

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≤

≤

Electrical Characteristics

V

= V

IN

Unless otherwise noted. Typical values are at T

Symbol Parameter Conditions Min. Typ. Max. Units

V

IN

I

Q

V

ENH

V

ENL

I

EN

R

DS-ON

I

LIM

I

lkg_(N)

I

lkg_(P)

Vref Reference Voltage 0.8 V

Notes:

5. Refer to the application section for further details.

6. For output voltages ≤ 1.2V a 40 µ F output capacitor value is required to achieve a maximum output accuracy of 3% while operating in power save

mode (PFM mode).

+ 0.6V(min. 2.5V) to 5.5V, I

OUT

Input Voltage 0 mA ≤ I

0 mA ≤ I

Quiescent Current I

OUT

I

OUT

switching (Note 5)

= 350mA, V

OUT

= 25°C.

A

600 mA 2.5 5.5 V

OUT

1000 mA 2.7 5.5 V

OUT

=1.2V, EN = V

OUT

, T

= -40°C to +85°C,

IN

A

= 0mA, Device is not switching 20 35

= 0mA, Device is

R2 =10K Ω

R2 =100K Ω

50

25

Shutdown Supply Current EN = GND 0.1 1

Undervoltage Lockout
Threshold

V

Rising 1.9 2.1 2.3 V

IN

Hysteresis 150 mV

Enable High Input Voltage 1.3 V

Enable Low Input Voltage 0.4 V

EN input bias current EN = V

PMOS On Resistance V

V

NMOS On Resistance V

V

P-channel current limit 2.5V < V

or GND 0.01 0.1

IN

= V

= 5.5V 250 350 m Ω

IN

GS

= V

= 2.5V 300 400

IN

GS

= V

= 5.5V 200 300 m Ω

IN

GS

= V

= 2.5V 250 350

IN

GS

< 5.5V 1300 1500 2000 mA

IN

Oscillator frequency 1000 1300 1500 KHz

N-channel leakage current V

P-channel leakage current V

Line regulation I

Load regulation 350 mA ≤ I

Output DC Voltage Accuracy
(Note 6)

Over-Temperature Protection PWM Mode Only

= 5.5V 0.1 1

DS

= 5.5V 0.1 1

DS

10 mA 0.16 %/V

OUT

1000 mA 0.15 %

OUT

0 mA ≤ I

350 mA ≤ I

1000 mA -3 +3 %

OUT

OUT

1000 mA

Rising
Temperature

150 °C

Hysteresis 20 °C

Start-Up Time I

= 1000 mA, C

OUT

= 20 µF 800 µS

OUT

µ

A

µ

A

µ

A

µ

A

µ

A

µ

A

µ

A

≤

≤

≤

≤

FAN2001/FAN2002 1A High-Efficiency Step-Down DC-DC Converter

FAN2001/FAN2002 Rev. 1.0.2

4

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