Richtek RT8003PQV Schematic [ru]

RT8003

600mA, 2MHz, High-Efficiency Synchronous Buck PWM
Converter

General Description

The RT8003 is a high-efficiency synchronous buck PWM
converter with integrated P-Channel and N-Channel power
MOSFET switches. Capable of delivering 600mA output
current over a wide input voltage range of 2.4V to 5.5V,
the RT8003 is ideally suited for portable applications
powered by a single Li-Ion battery or by 3-cell NiMH/NiCd
batteries. The device operates at 2MHz PWM switching
fixed frequency, can use smaller CIN, C
inductor.

The RT8003 integrates two low R

DS(ON)

of high- and low-side switching MOSFETs to reduce board
space, as only resistors and capacitors along with one
inductor are required externally for operation. The RT8003
has adjustable output range down to 0.5V. The other
features include internal soft-start, chip enable, over­temperature and over-current protections. It is available in
a space-saving VDFN-10L 3x3 package.

capacitor and

OUT

230mΩ and 180mΩ

Features

l 2.4V to 5.5V Input Voltage Range
l Adjustable Output from 0.5V to V
l Guaranteed 600mA Output Current
l Accurate Reference : 0.5V (± 1.5%)
l Up to 90% Conversion Efficiency
l Typical Quiescent Current : 200µA
l Integrated Low R

High- and Low-Side Power

DS(ON)

IN

MOSFET Switches : 230mΩ and 180mΩ

l Current Mode PWM Operation
l Fixed Frequency : 2MHz
l 100% Maximum Duty Cycle for Lowest Dropout
l Internal Soft-Start
l No Schottky Diode Required
l Over-Temperature and Over-Current Protection
l Small 10-Lead VDFN 3x3 Package
l RoHS Compliant and 100% Lead (Pb)-Free

Applications

Ordering Information

RT8003

Package Type
QV : VDFN-10L 3x3 (V-Type)

Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer­ cial Standard)

Note :
Richtek Pb-free and Green products are :

} RoHS compliant and compatible with the current require-

ments of IPC/JEDEC J-STD-020.

} Suitable for use in SnPb or Pb-free soldering processes.
} 100% matte tin (Sn) plating.

Marking Information

For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area, otherwise visit our website for detail.

l Battery-Powered Equipments
l Low Power CPU and DSP Supplies
l Digital Cameras and Hard Disks
l Protable Instruments and Notebook Computers
l Celluar Phones, PDAs, and Handheld PCs
l USB-Based DSL Modems and Other Network Interface

Cards

Pin Configurations

(TOP VIEW)

1

LX

2

VDD

3

NC

4

NC

5

EN

VDFN-10L 3x3

GND

10

GND

9

GND

8

GND

7

COMP

9

11

FB

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RT8003

Typical Application Circuit

V

IN

2.4V to 4.2V

Chip Enable

Recommended component selection for Typical Application Circuit.

V

(V) VIN (V) CIN (µF) C

OUT

0.5 2.4 to 3.3

1 1/2.2 2.2/1 10 Open 10

C

1uF

C

COMP

10nF

OUT

IN

5

EN

7

(µF) L

2

VDD

LX

RT8003

FBCOMP

GND

8, 9, 10,
Exposed Pad (11)

(µH) R1 (kΩ) R2 (k Ω) C

OUT

1

6

L

2.2uH

OUT

R1
10k

R2

7.15k

V

OUT

1.2V/600mA

C

OUT

1uF

COMP

(nF)

1 2.4 to 3.6

1.2 2.4 to 4.2

1.8 2.4 to 5.5

2.5 3.3 to 5.5

3.3 4.2 to 5.5

1 1/2.2 2.2/1 10 10 10
1 1/2.2 2.2/1 10 7.15 10
1 1/2.2 2.2/1 10 3.83 10
1 1/2.2 2.2/1 10 2.49 10
1 1/2.2 2.2/1 10 1.78 10

Suggested Inductors

Component

Supplier

ABC SR0302

Sumida CDRH2D14

TDK VLP4612

Series Inductance

(µH)

1

2.2

2.2 94 1000 3.2x3.2x1.55
1

2.5

Suggested Capacitors For CIN and C
Component Supplier

TDK

C1608X5R1A105M 1 0603

Part No. Capacitance (uF) Case Size

C1608X5R1A225M 2.2 0603

Panasonic

ECJ1VB0J105M 1 0603
ECJ1VB0J225M 2.2 0603

TAIYO YUDEN

JMK107BJ105M 1 0603
JMK107BJ225M 2.2 0603

OUT

ESR

(mΩ)

60
90

110
170

Current Rating

(mA)

2100
1650

1500
1100

Dimensions

(mm)

3x2.8x2.5

4.6x3.4x1.2

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Functional Pin Description

Power Input Supply. Input voltage which supplies current to the output pin. Connect

Floating this pin is

Switcher Feedback Voltage. This pin is the inverting input of the error amplifier. FB

resistor divider network. FB

Compensation Input. This pin is the output of the internal error amplifier. Connect

and ground plane with

The exposed pad must be

).

t

signal, compensation and

RT8003

Pin No. Pin Name

1 LX Internal Power MOSFET Switches Output. Connect this pin to the inductor.
2 VDD

this pin with a low-ESR capacitor to GND

3, 4 NC No Internal Connection

5 EN

6 FB

Chip Enable (Active High). Logic low shuts down the converter.
forbidden.

senses the switcher output through an external
regulation voltage is 0.5V.

7 COMP

an external capacitor to compensate the regulator controlled loop.
Ties the pin directly to the cathode terminal of CIN and C

the lowest impedance. Signal and Common Ground (

8, 9, 10, 11

(Exposed Pad)

GND

soldered to a large PCB and connected to GND for maximum power dissipation
The GND pad area should be as large as possible and using many vias to conduc
the heat into the buried GND plate of PCB layer. All small­feedback components should connect to this pin.

Function Block Diagram

Pin Function

OUT

COMP

FB

EN

Shutdown

Control

Oscillator

V

REF

Slope

Compensation

+

Error

Amplifier

-

Current Limit

Detector

-

PWM

Comparator

+

Over

Temperature

Detector

Control

Logic

Zero

Detector

Current

Sense

Driver

VDD

LX

GND

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RT8003

Absolute Maximum Ratings (Note 1)

l Supply Voltage ---------------------------------------------------------------------------------------------------−0.3V to 6V
l LX Voltage---------------------------------------------------------------------------------------------------------−0.3V to (V
l Power Dissipation, P

@ T

D

= 25°C

A

VDFN-10L 3x3----------------------------------------------------------------------------------------------------1.923W

l Package Thermal Resistance (Note 2)

VDFN-10L 3x3, θJA-----------------------------------------------------------------------------------------------52°C/W

l Junction Temperature-------------------------------------------------------------------------------------------150°C
l Lead Temperature (Soldering, 10 sec.)----------------------------------------------------------------------260°C
l Storage Temperature Range-----------------------------------------------------------------------------------−65°C to 150°C
l ESD Susceptibility (Note 3)

HBM (Human Body Mode)-------------------------------------------------------------------------------------2kV
MM (Machine Mode)--------------------------------------------------------------------------------------------200V

Recommended Operating Conditions (Note 4)

l Supply Voltage---------------------------------------------------------------------------------------------------2.4V to 5.5V
l Enable Input Voltage,
l Ambient Temperature Range----------------------------------------------------------------------------------−40°C to 85°C
l Junction Temperature Range----------------------------------------------------------------------------------0°C to 125°C

-------------------------------------------------------------------------------------0V to 5.5V

VEN

DD

+ 0.3V)

Electrical Characteristics

(V

= 3.3V, T

DD

Supply Current

Quiescent Current

Shutdown Current I

Reference

Reference Voltage V

Oscillator

Switching Frequency Range
Maximum Duty Cycle DC

Output Voltage

Line Regulation
Load Regulation 10mA < I

Power Switches

R

DS(ON)

R

DS(ON)

Current Limit

= 25°C, unless otherwise specified)

A

Parameter Symbol

IQ

SHDN

REF

f

OSC

of P-Channel MOSFET R
of N-Channel MOSFET R

P_FET
N_FET

I

LIMIT

V

= 3.3V, V

EN

I

OUT

V

= 0V -- 0.01

EN

0.4925 0.5 0.5075 V

1.7 2.0 2.3 MHz
V

= V

DD

V

= 2.4V to 5.5V, I

DD

V

V

= 3.3V, ILX = 300mA

DD

V

= 3.3V, ILX = −300mA

DD

= 3.3V, V

DD

Test Conditions Min Typ Max Unit

= 0mA

OUT

LOAD

= V

FB

< 600mA -- -- +1.5

+ 0.15V,

REF

LOAD

= 100mA

90 200 400 µA

100 -- -- %

-- -- +1.5

100 230 600 mΩ
100 180 600

FB

= V

REF

- 0.15V

1.6 2 2.4 A

To be continued

1 µA

%
%

mΩ

DS8003-06 August 2007www.richtek.com

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