RT9018A-10GSP - Richtek - Product.Network

RT9018A/B

DS9018A/B-09 April 2012 www.richtek.com

Pin Configurations

Maximum 3A, Ultra Low Dropout Regulator

Ordering Information

Features

zMaximum 3A Low-Dropout Voltage Regulator

zHigh Accuracy Output Voltage ±±

±±

±1.5%

zTypically 210mV Dropout at 3A

zPower Good Output

zOutput Voltage Pull Low Resistance when Disable

zThermal and Over Current Protection

zRoHS Compliant and 100% Lead (Pb)-Free

Applications

zFront Side Bus VTT (1.2V/3A)

zNoteBook PC Applications

zMotherboard Applications

Marking Information

For marking information, contact our sales representative

directly or through a Richtek distributor located in your

area.

(TOP VIEW)

WDFN-10L 3x3

General Description

The RT9018A/B is a high performance positive voltage

regulator designed for use in applications requiring very

low Input voltage and very low dropout voltage at up to

3A(Peak). It operates with a VIN as low as 1.4V and VDD

voltage 3V with output voltage programmable as low as

0.8V. The significant feature includes ultra low dropout,

ideal for applications where VOUT is very close to VIN.

Additionally, there is an enable pin to further reduce power

dissipation while shutdown. The RT9018A/B provides

excellent regulation over variations in line, load and

temperature. and provides a power OK signal to indicate

if the voltage level of Vo reaches 90% of its rating value.

The RT9018A/B is available in the SOP-8 (Exposed Pad)

and WDFN-10L 3x3 packages with 1V, 1.05V, 1.2V, 1.5V,

1.8V and 2.5V internally preset outputs that are also

adjustable using external resistors.

SOP-8 (Exposed Pad)

PGOOD

VIN

VDD

GND

ADJ

VOUT

GND

VOUT

PGOOD

ADJ

VDD

VIN

VOUT

GND

Note :

Richtek 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.

RT9018A/B-

Package Type

SP : SOP-8 (Exposed Pad-Option 1)

QW : WDFN-10L 3x3

Enable Pin Function

A : Internal Pull High

B : Internal Pull Low

Output Voltage

10 : 1V/Adj

1K : 1.05V/Adj

12 : 1.2V/Adj

15 : 1.5V/Adj

18 : 1.8V/Adj

25 : 2.5V/Adj

Lead Plating System

P : Pb Free

G : Green (Halogen Free and Pb Free)

Z : ECO (Ecological Element with

Halogen Free and Pb free)

RT9018A/B

DS9018A/B-09 April 2012www.richtek.com

Function Block Diagram

Typical Application Circuit

Function Pin Description

Pin No.

SOP-8

(Exposed Pad) WDFN -1 0L 3x3 Pin

Name Pin Functi on

3 7, 8, 9 VIN Supply Input Voltage.

2 6 EN Chip Enable (Active-High).

4 10 VDD Supply Voltage of Control Circuitry.

1 5 PGOOD Power Good Open Drain Output.

7 4 ADJ

Set the output voltage by the internal feedback resistors when

ADJ is grounded. If external feedback resistors is used, VOUT =

0.8V x (R1 + R2)/R2.

6 1, 2, 3 VOUT Output Voltage.

5 -- NC No Internal Connection.

9 (Exposed Pad) 11 (Exposed Pad) GND Ground. The exposed pad must be soldered to a large PCB

and connected to GND for maximum power dissipation.

Figure 1. Fixed Voltage Regulator Figure 2. Adjustable Voltage Regulator

R2R1

0.8 VOUT +

×=

VIN

GND

VOUT

ADJ

PGOOD

RT9018A/B

VOUT

10µF

Chip Enable

100k

VOUT

VDD

1µF

VDD

VIN

CDummy

OCP

Error

Amplifier

POR

GND

ADJ

VIN

PGOOD

VOUT

VDD

Mode

0.8V

0.72V

Driver

OTP

VIN

GND

VOUT

ADJ

PGOOD

RT9018A/B

VOUT

Chip Enable

100k

VOUT

VDD

VIN

10µF

1µF

RT9018A/B

DS9018A/B-09 April 2012 www.richtek.com

Electrical Characteristics

(VIN = VOUT + 500mV, VEN = VDD = 5V, CIN = COUT = 10μF, T A = TJ = 25°C, unless otherwise specified)

Recommended Operating Conditions (Note 4)

zSupply Voltage, VIN ------------------------------------------------------------------------------------------------------- 1.4V to 5.5V

zControl Voltage, VDD (VDD > VOUT + 1.5V) -------------------------------------------------------------------------- 3V to 5.5V

zControl Voltage with PGOOD, VDD (Note 8) ----------------------------------------------------------------------- 4.5V to 5.5V

zJunction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C

zAmbient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C

Absolute Maximum Ratings (Note 1)

zSupply Voltage, VIN ------------------------------------------------------------------------------------------------------ 1V to 6V

zControl Voltage, VDD ----------------------------------------------------------------------------------------------------- 3V to 6V

zOutput Voltage, VOUT --------------------------------------------------------------------------------------------------- 0.8 to 6V

zPower Dissipation, PD @ TA = 25°C

SOP-8 (Exposed Pad) --------------------------------------------------------------------------------------------------- 1.33W

WDFN-10L 3x3 ------------------------------------------------------------------------------------------------------------- 1.67W

zPackage Thermal Resistance (Note 2)

SOP-8 (Exposed Pad), θJA ---------------------------------------------------------------------------------------------- 75°C/W

SOP-8 (Exposed Pad), θJC --------------------------------------------------------------------------------------------- 15°C/W

WDFN-10L 3x3, θJA ------------------------------------------------------------------------------------------------------- 60°C/W

zJunction Temperature ----------------------------------------------------------------------------------------------------- 150°C

zLead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------- 260°C

zStorage Temperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C

zESD Susceptibility (Note 3)

HBM (Human Body Mode) ---------------------------------------------------------------------------------------------- 2kV

MM (Machine Mode) ------------------------------------------------------------------------------------------------------ 200V

Parameter Symbol Test Conditions Min Typ Max Unit

POR Threshold 2.4 2.7 3 V

POR Hysteresis 0.15 0.2 -- V

Adjustable Pin Threshold VTH_ADJ I

OUT = 1mA -- 0.2 0.4 V

Reference Voltage (ADJ Pin Voltage) VADJ I

OUT = 1mA 0.788 0.8 0.812 V

Fixed Output Voltage Range ΔVOUT −1.5 0 1.5 %

Line Regulation (VIN) ΔVLINE_IN VIN = VOUT + 0.5V to 5V,

IOUT = 1mA -- 0.2 0.6 %

Load Regulation (Note 5) ΔVLOAD VIN = VOUT + 1V,

IOUT = 1mA to 3A -- 0.2 1 %

IOUT = 2A -- 150 250

Dropout Voltage (Note 6) VDROP IOUT = 3A -- 210 350 mV

Quiescent Current (Note 7) IQ V

DD = 5.5V -- 0.6 1.2 mA

Current Limit ILIM 3.2 4.5 -- A

RT9018A/B

DS9018A/B-09 April 2012www.richtek.com

Note 1. Stresses beyond those listed “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 may

affect device reliability.

Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is

measured at the exposed pad of the package.

Note 3. Devices are ESD sensitive. Handling precaution recommended.

Note 4. The device is not guaranteed to function outside its operating conditions.

Note 5. Regulation is measured at constant junction temperature by using a 2ms current pulse. Devices are tested for load

regulation in the load range from 1mA to 3A.

Note 6. The dropout voltage is defined as VIN -VOUT, which is measured when VOUT is VOUT(NORMAL) - 100mV.

Note 7. Quiescent, or ground current, is the difference between input and output currents. It is defined by IQ = IIN - IOUT under no

load condition (IOUT = 0mA). The total current drawn from the supply is the sum of the load current plus the ground pin

current.

Note 8. The control voltage must within 4.5V to 5.5V when using PGOOD function.

Parameter Symbol Test Conditions Min Typ Max Unit

Short Circuit Current VOUT < 0.2V 0.5 1.8 -- A

In-rush Current COUT = 10μF, Enable Start-up -- 0.6 -- A

VOUT Pull Low Resistance VEN = 0V -- 150 -- Ω

Chip Enable

EN Input Bias Current IEN V

EN = 0V -- 12 -- μA

RT9018A -- 10 20 VDD Shutdown

Current RT9018B ISHDN V

EN = 0V -- -- 1

μA

Logic-Low VENL V

DD = 5V -- -- 0.7

EN Threshold Voltage Logic-High VENH V

DD = 5V 1.2 -- -- V

Power Good

PGOOD Rising Threshold -- 90 93 %

PGOOD Hysteresis 3 10 -- %

PGOOD Sink Capability IPGOOD = 10mA -- 0.2 0.4 V

PGOOD Delay 0.5 1.5 5 ms

Thermal Protection

Thermal Shutdown Temperature TSD -- 160 -- °C

Thermal Shutdown Hysteresis ΔTSD -- 30 -- °C

Thermal Shutdown Temperature

Fold-back V

OUT < 0.4V -- 110 -- °C

RT9018A/B

DS9018A/B-09 April 2012 www.richtek.com

Typical Operating Characteristics

Load Transient Response

Time (2.5ms/Div)

IOUT

(1A/Div)

VOUT

(20mV/Div)

VDD = 5V, VIN = 1.8V, VOUT = 1.2V

VIN Line Transient Response

Time (250μs/Div)

VOUT

(20mV/Div)

VIN

VDD = 5V, VOUT = 1.2V, IOUT = 0A

VIN Line Transient Response

Time (250μs/Div)

VOUT

(20mV/Div)

VIN

VDD = 5V, VOUT = 1.2V, IOUT = 2A

Load Transient Response

Time (2.5ms/Div)

IOUT

(1A/Div)

VOUT

(20mV/Div)

VDD = 5V, VIN = 1.8V, VOUT = 1.2V

VDD Line Transient Response

Time (250μs/Div)

VOUT

(20mV/Div)

VDD

VIN = 1.8V, VOUT = 1.2V, IOUT = 2A

VDD Line Transient Response

Time (250μs/Div)

VOUT

(20mV/Div)

VDD

VIN = 1.8V, VOUT = 1.2V, IOUT = 0A

RT9018A/B

DS9018A/B-09 April 2012www.richtek.com

Short Circuit Current vs . Te m pe rature

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

-40 -20 0 20 40 60 80 100

Temperature (°C)

Short Circuit Current Ishort (A

)

Dropout Voltage vs. Load Current

100

150

200

250

300

350

400

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3

Load Current (A)

Dropout Voltage (mV)

125°C

25°C

-40°C

Start Up from VDD

Time (500μs/Div)

PGOOD

(1V/Div)

VDD

(5V/Div)

IOUT = 3A

VOUT

(1V/Div)

IIN

(2A/Div)

Start Up from VIN

Time (1ms/Div)

PGOOD

(1V/Div)

VIN

(1V/Div)

IOUT = 3A

VOUT

(1V/Div)

IIN

(2A/Div)

Short Circuit Protection

Time (100μs/Div)

IOUT

(1A/Div)

VDD = 5V, VIN = 1.8V, VOUT = 1.2V

Start Up from Enable

Time (500μs/Div)

PGOOD

(1V/Div)

IOUT = 3A

VOUT

(1V/Div)

IIN

(2A/Div)

RT9018A/B

DS9018A/B-09 April 2012 www.richtek.com

ADJ Threshold Voltage vs . Temperature

0.10

0.12

0.14

0.16

0.18

0.20

0.22

0.24

0.26

0.28

0.30

-40 -25 -10 5 20 35 50 65 80 95 110 125

Temperature (°C)

ADJ Threshold Voltage Range (V

)

Reference Voltage vs. Temperature

0.76

0.77

0.78

0.79

0.80

0.81

0.82

0.83

0.84

-40 -25 -10 5 20 35 50 65 80 95 110 125

Temperature (°C)

Reference Voltage (V)

VDD Standby Current vs. Temperature

-4

-50-25 0 25 50 75100125

Temperature (°C)

VDD Standby Current (μA) 1

VIN = 3.3V, VEN = 0V, VDD = 5V

RT9018A

RT9018B

Output Voltage vs. Temperature

1.15

1.16

1.17

1.18

1.19

1.20

1.21

1.22

1.23

1.24

1.25

-40 -25 -10 5 20 35 50 65 80 95 110 125

Temperature (°C)

Output Voltage (V)

VIN = 1.8V, VADJ = 0V, IOUT = 0A

VDD POR Threshold Voltage vs. Temperature

2.40

2.45

2.50

2.55

2.60

2.65

2.70

2.75

2.80

2.85

2.90

2.95

3.00

-40 -25 -10 5 20 35 50 65 80 95 110 125

Temperature (°C)

POR Voltage (V)

Rising

Falling

Quiescent Current vs. Temperature

100

200

300

400

500

600

700

800

900

1000

1100

1200

-40 -25 -10 5 20 35 50 65 80 95 110 125

Temperature (°C)

Quiescent Current (uA

)

VIN = 1.8V, VOUT = 1.2V, IOUT = 0A

Quiescent Current (mA)

1.2

1.1

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

RT9018A/B

DS9018A/B-09 April 2012www.richtek.com

Ov e r Current Protection Fold Back

0.5

1.5

2.5

0 0.5 1 1.5 2 2.5 3 3.5 4

Loading Current IOUT (A)

Output Voltage V

OUT (V)

VIN = VEN = 3.3V, VDD = 5V

RT9018A/B

DS9018A/B-09 April 2012 www.richtek.com

Application Information

Adjustable Mode Operation

The output voltage of RT9018A/B is adjustable from 0.8V

to (VIN - VDROP) by external voltage divider resisters as

shown in Typical Application Circuit (Figure 2). The value

of resisters R1 and R2 should be more than 10kΩ to

reduce the power loss. The VDD must be greater than

(VOUT + 1.5V).

Enable

The RT9018A/B goes into shutdown mode when the EN

pin is in the logic low condition. During this condition, the

pass transistor, error amplifier, and band gap are turned

off, reducing the supply current to 10μA typical. The

RT9018A/B goes into operation mode when the EN pin is

in the logic high condition. If the EN pin is floating, NOTE

that the RT9018A/B internal initial logic level. For RT9018A,

the EN pin function pulls high level internally. So the

regulator will be turn on when EN pin is floating. For

RT9018B, the EN pin function pulls low level internally.

So the regulator will be turn off when EN pin is floating.

Output Ca pa citor

The RT9018A/B is specifically designed to employ ceramic

output capacitors as low as 10μF. The ceramic capacitors

offer significant cost and space savings, along with high

frequency noise filtering.

Input Capacitor

Good bypassing is recommended from input to ground to

help improve AC performance. A 10μF input capacitor or

greater located as close as possible to the IC is

recommended.

Current Limit

The RT9018A/B contains an independent current limit and

the short circuit current protection to prevent unexpected

applications. The current limit monitors and controls the

pass transistor’s gate voltage, limiting the output current

to higher than 4.5A typical. When the output voltage is

less than 0.4V, the short circuit current protection starts

the current fold back function and maintains the loading

current 1.8A. The output can be shorted to ground

indefinitely without damaging the part.

Power Good

The power good function is an open-drain output. Connects

100kΩ pull up resistor to VOUT to obtain an output voltage.

The PGOOD pin will output high immediately after the

output voltage arrives 90% of normal output voltage. The

PGOOD pin will output high with typical 1.5ms delay time.

Thermal-Shutdown Protection

Thermal protection limits power dissipation to prevent IC

over temperature in RT9018A/B. When the operation

junction temperature exceeds 160°C, the over-temperature

protection circuit starts the thermal shutdown function

and turns the pass transistor off. The pass transistor turn

on again after the junction temperature cools by 30°C.

RT9018A/B lowers its OTP trip level from 160°C to 110°C

when output short circuit occurs (VOUT < 0.4V). It limits

IC case temperature under 100°C and provides maximum

safety to customer while output short circuit occurring.

Power Dissipation

For continuous operation, do not exceed absolute

maximum operation junction temperature 125°C. The

power dissipation definition in device is :

PD = (VIN − VOUT) x IOUT + VIN x IQ

The maximum power dissipation depends on the thermal

resistance of IC package, PCB layout, the rate of

surroundings airflow and temperature difference between

junctions to ambient. The maximum power dissipation can

be calculated by following formula :

PD(MAX) = (TJ(MAX) − TA) / θJA

Where TJ(MAX) is the maximum operation junction

temperature 125°C, TA is the ambient temperature and the

θJA is the junction to ambient thermal resistance.

For recommended operating conditions specification,

where TJ (MAX) is the maximum junction temperature of

the die (125°C) and TA is the maximum ambient

temperature. The junction to ambient thermal resistance

for SOP-8 (Exposed Pad) package is 75°C/W on the

standard JEDEC 51-7 (4 layers, 2S2P) thermal test board.

The copper thickness is 2oz. The maximum power

dissipation at TA = 25°C can be calculated by following

RT9018A/B

DS9018A/B-09 April 2012www.richtek.com

Figure 3 (a). Minimum Footprint, θJA = 75°C/W

Figure 3 (b). Copper Area = 10mm2, θJA = 64°C/W

Figure 3 (c). Copper Area = 30mm2, θJA = 54°C/W

Figure 4. De-rating Curves

Figure 3. Thermal Resistance vs. Different Cooper Area

Layout Design

Figure 3 (d). Copper Area = 50mm2, θJA = 51°C/W

Figure 3 (e). Copper Area = 70mm2, θJA = 49°C/W

0.2

0.4

0.6

0.8

1.2

1.4

1.6

1.8

2.2

0 20 40 60 80 100 120 140

Ambient Temperature (°C)

Power Dissipation (W)

JEDEC 4-Layers PCB

70mm2

50mm2

30mm2

10mm2

Minimum Layout

Copper Area

The maximum power dissipation depends on operating

ambient temperature for fixed TJ(MAX) and thermal

resistance θJA . The Figure 4 of de-rating curves allows

the designer to see the effect of rising ambient temperature

on the maximum power allowed.

Layout Considerations

The thermal resistance θJA of SOP-8 (Exposed Pad) is

determined by the package design and the PCB design.

However, the package design had been designed. If

possible, it’s useful to increase thermal performance by

the PCB design. The thermal resistance θJA can be

decreased by adding a copper under the exposed pad of

SOP-8 (Exposed Pad) package.

As shown in Figure 3, the amount of copper area to which

the SOP-8 (Exposed Pad) is mounted affects thermal

performance. When mounted to the standard SOP-8

(Exposed Pad) pad (Figure 3.a), θJA is 75°C/W. Adding

copper area of pad under the SOP-8 (Exposed Pad) Figure

3.b) reduces the θJA to 64°C/W. Even further, increasing

the copper area of pad to 70mm2 (Figure 3.e) reduces the

θJA to 49°C/W.

formula :

PD (MAX) = (125°C − 25°C) / (75°C/W) = 1.33W (SOP-8

Exposed Pad on the minimum layout)

RT9018A/B

DS9018A/B-09 April 2012 www.richtek.com

Outline Dimension

EXPOSED THERMAL PAD

(Bottom of Package)

8-Lead SOP (Exposed Pad) Plastic Package

Dime nsio ns In Millime ters Dimensions In Inches

Symbol Min Max Min Max

A 4.801 5.004 0.189 0.197

B 3.810 4.000 0.150 0.157

C 1.346 1.753 0.053 0.069

D 0.330 0.510 0.013 0.020

F 1.194 1.346 0.047 0.053

H 0.170 0.254 0.007 0.010

I 0.000 0.152 0.000 0.006

J 5.791 6.200 0.228 0.244

M 0.406 1.270 0.016 0.050

X 2.000 2.300 0.079 0.091

Option 1 Y 2.000 2.300 0.079 0.091

X 2.100 2.500 0.083 0.098

Option 2 Y 3.000 3.500 0.118 0.138

RT9018A/B

DS9018A/B-09 April 2012www.richtek.com

Richtek Technology Corporation

5F, No. 20, Taiyuen Street, Chupei City

Hsinchu, Taiwan, R.O.C.

Tel: (8863)5526789

Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should

obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot

assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be

accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third

parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries.

Dimension s In Millimeters Dimensions In Inches

Symb ol Min Max Min Max

A 0.700 0.800 0.028 0.031

A1 0.000 0.050 0.000 0.002

A3 0.175 0.250 0.007 0.010

b 0.180 0.300 0.007 0.012

D 2.950 3.050 0.116 0.120

D2 2.300 2.650 0.091 0.104

E 2.950 3.050 0.116 0.120

E2 1.500 1.750 0.059 0.069

e 0.500 0.020

L 0.350 0.450

0.014 0.018

W-Type 10L DFN 3x3 Package

Note : The configuration of the Pin #1 identifier is optional,

but must be located within the zone indicated.

DETAIL A

Pin #1 ID and Tie Bar Mark Options

SEE DETAIL A