Richtek RT9012-FMPQV, RT9012-FMPQW, RT9012-FSPQW, RT9012-GMPQV, RT9012-GMPQW Schematic [ru]

300mA Dual LDO Regulator with POR

RT9012

General Description

RT9012 is a dual channel, low noise, and low dropout with

the sourcing ability up to 300mA and power-on reset

function. The range of output voltage is from 1.2V to 3.6V

by operating from 2.5V to 5.5V input.

The RT9012 offers 2% accuracy, extremely low dropout

voltage (240mV @ 300mA), and extremely low ground

current, only 27uA per LDO. The shutdown current is near

zero current which is suitable for battery-power devices.

Other features include current limiting, over temperature,

output short circuit protection.

The RT9012 is short circuit thermal folded back protected.

The IC lowers its OTP trip point from 165°C to 110°C when

output short circuit occurs (VOUT < 0.4V) providing

maximum safety to end users.

The RT9012 can operate stably with very small ceramic

output capacitors, reducing required board space and

component cost. The RT9012 is available in fixed output

voltages in the

WDFN-8L 2x2 package.

Ordering Information

RT9012-

Package Type
QW : WDFN-8L 2x2 (W-Type)

Features

z Wide Operating Voltage Ranges : 2.5V to 5.5V
z Low-Noise for RF Application
z No Noise Bypass Capa citor Required
z Fast Response in Line/Load Transient
z TTL-Logic-Controlled Shutdown Input
z Low Temperature Coefficient

zz

z Dual LDO Outputs (300mA/300mA)

zz

zz

z Ultra-low Quiescent Current 27uA/LDO

zz

zz

z High Output Accuracy 2%

zz

zz

z Short Circuit Protection

zz

zz

z Thermal Shutdown Protection

zz

zz

z Current Limit Protection

zz

zz

z Short Circuit Thermal Folded Back Protection

zz

zz

z Tiny 8-Lead WDFN Package

zz

zz

z RoHS Compliant and 100% Lead (Pb)-Free

zz

Applications

zz

z CDMA/GSM Cellular Handsets

zz

zz

z Battery-Powered Equipment

zz

zz

z Laptop, Palmtops, Notebook Computers

zz

zz

z Hand-Held Instruments

zz

zz

z PCMCIA Cards

zz

zz

z Portable Information Appliances

zz

Lead Plating System
P : Pb Free
G : Green (Halogen Free and Pb Free)

Output Voltage : VOUT1/VOUT2
VOUT2 > VOUT1 is Recommended

Note :

Pin Configurations

(TOP VIEW)

1

VIN

2

EN1

3

EN2

4

SET

WDFN-8L 2x2

8

VOUT1

7

VOUT2
POR

6

9

5

GND

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.

Marking Information

For marking information, contact our sales representative

directly or through a Richtek distributor located in your

area.

Available Voltage Version

Code Voltage Code Voltage Code Voltage

A 3.5 B 1.3 C 1.2

D 1.85 E 2.1 F 1.5

G 1.8 H 2 J 2.5

K 2.6 L 2.7 M 2.8
N 2.85 P 3 Q 3.1

R 3.2 S 3.3 T 2.65
V 2.9 W 1.6 X 3.15
Y 1.9

DS9012-09 April 2011 www.richtek.com

1

RT9012

Typical Application Circuit

100K

V

IN

C

IN

1uF

Chip Enable

C

DELAY

VIN

EN1

EN2

SET

RT9012

VOUT1

VOUT2

GND

Functional Pin Description

Pin No. Pin Na me P in Func tion

1 VIN Supply Input.

2 EN1 Chip Enable1 (Active High).

3 EN2 Chip Enable2 (Active High).

4 SET Delay Set Input. Connect external capacitor to GND to set the internal delay.

5 GND Common Ground.

POR

C

OUT1

1uF

C

OUT2

1uF

V

V

OUT1

OUT2

6 POR

7 VOUT2 Channel 2 Output Voltage.

8 VOUT1 Channel 1 Output Voltage.

9 (Exposed Pad) GND

Power-On Reset Output : Open-drain output. Active low indicates an output

under-voltage condition on regulator 2.

The exposed pad must be soldered to a large PCB and connected to GND

for maximum power dissipation.

DS9012-09 April 2011www.richtek.com

2

Function Block Diagram

RT9012

EN1

EN2

0.2uA

0.2uA

Shutdown

and

Logic Control

V

REF

-

+

Error

Amplifier

Shutdown

Logic Control

V

REF

-

+

Error

Amplifier

MOS Driver

Current-Limit

and

Thermal

Protection

and

MOS Driver

Current-Limit

and

Thermal

Protection

VIN

VOUT1

GND

VOUT2

SET

POR& Delay

GND

POR

DS9012-09 April 2011 www.richtek.com

3

RT9012

Absolute Maximum Ratings (Note 1)

z Supply Input Voltage ------------------------------------------------------------------------------------------------------ 6V

z Other I/O Pin Voltages --------------------------------------------------------------------------------------------------- 6V

z Power Dissipation, P

WDFN-8L 2x2 -------------------------------------------------------------------------------------------------------------- 0.606W

z Package Thermal Resistance (Note 2)

WDFN-8L 2x2, θJA--------------------------------------------------------------------------------------------------------- 165°C/W

z Junction Temperature ----------------------------------------------------------------------------------------------------- 150°C

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

z Storage Temperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C

z ESD Susceptibility (Note 3)

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

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

Recommended Operating Conditions (Note 4)

z Supply Input Voltage ------------------------------------------------------------------------------------------------------ 2.5V to 5.5V

z Enable Input Voltage ------------------------------------------------------------------------------------------------------ 0V to 5.5V
z Operation Junction Temperature Range ------------------------------------------------------------------------------ −40°C to 125°C
z Operation Ambient Temperature Range ------------------------------------------------------------------------------ −40°C to 85°C

@ T

D

= 25°C

A

Electrical Characteristics

(V

= V

OUT

+ 1V, V

IN

Parameter Symbol Test Conditions Min Typ Max Unit

Input Voltage

Dropout Voltage (Note 5)

Output voltage range

V

Accuracy

OUT

Line Regulation

Load Regulation

Current Limit

Quiescent Current

Shutdown Current

EN Threshold

Output Voltage TC -- 100 -- ppm/°C

= VIN, C

EN

= C

IN

= 1μF, TA = 25°C, unless otherwise specified.)

OUT

V

V

IN

V

DROP

V

OUT

ΔV

ΔV

LINE

ΔV

LOA D

I

VEN > 1.5V

Q

I

VEN < 0.4V

Q_SD

VIH V

V

V

IL

= 2.5V to 5.5V

IN

I

= 150mA

OU T

= 300mA

I

OU T

1.2 -- 3.6 V

I

= 1mA

OU T

V

= (V

IN

> 2.5V, whichever is larger

V

IN

1mA < I

R

LOA D

= 2.5V to 5.5V, Power On

IN

= 2.5V to 5.5V, Shutdown

IN

+ 0.3V) to 5.5V or

OUT

< 300mA

OUT

= 1Ω

2.5 -- 5.5 V

-- 120 --

mV

-- 240 -- mV

-2 -- +2 %

-- -- 0.2 %/V

-- -- 0.6 %

330 450 700 mA

-- 58 80 μA

-- -- 1 μA

1.5 -- -­V

-- -- 0.4

Thermal Shutdown

Thermal Shutdown Hysteresis

4

T

ΔT

SD

SD

-- 170 -- °C

-- 40 --

°C

To be continued

DS9012-09 April 2011www.richtek.com

Parameter Symbol Test Conditions Min Typ Max Unit

PSRR
I

= 10mA

LOAD

PSRR
I

= 150mA

LOAD

Power Good

PSRR

PSRR

RT9012

f =100Hz -- 65 --

f =1kHz -- 60 --

f =10k Hz -- 50 --

f =100Hz -- 65 --

f =1kHz -- 50 --

f =10k Hz -- 50 --

dB

dB

V

THL

Low Threshold, % of nominal
V

(Flag On)

OUT2

90 -- -- %

Reset Threshold

POR Output Logic Low Voltage

POR Leakage Current I

Set pin Current Source

V

THH

V

OL

POR

High Threshold, % of nominal

I

V

OUT2

LOW

(Flag Off)

= 250uA

Flag Off -1 0.01 1 μA

= 0

V

SET

-- -- 96 %

-- 0.02 0.1 V

0.60 1.25 1.70 μA

Set pin Threshold POR = high -- 1.4 -- V

Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for

stress ratings. 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 remain possibility to affect device reliability.

Note 2. θ

Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
Note 5. The dropout voltage is defined as V

is measured in the natural convection at TA = 25°C on a low effective thermal conductivity test board of

JA

JEDEC 51-3 thermal measurement standard.

-V

IN

, which is measured when V

OUT

OUT

is V

OUT(NORMAL)

− 100mV.

DS9012-09 April 2011 www.richtek.com

5

RT9012

Typical Operating Characteristics

Output Voltage vs. Temperature

1.9

RT9012-GS, V

1.85

1.8

Output Voltage (V)

1.75

1.7

-50 -25 0 25 50 75 100 125

OUT1

Temperature

(°C)

Quiescent Current vs. Temperature

70

RT9012-GS
VIN = V

CIN = C

65

60

55

Quiescent Current (uA)

EN

OUT1

= 4.3V

= C

OUT2

= 1uF/X7R

Output Voltage vs. Temperature

3.4

RT9012-GS, V

3.35

3.3

3.25

Output Voltage (V)

3.2

-50 -25 0 25 50 75 100 125

OUT2

Temperature

(°C)

Dropout Voltage vs. Load Current

350

RT9012-GS, V

300

250

200

150

100

Dropout Voltage (mV)

50

OUT2

TJ = 125°C

TJ = 25°C

TJ = -40°C

50

-50 -25 0 25 50 75 100 125

Temperature

(°C)

PSRR

20

RT9012-FM, V

VIN = 4.3V ± 0.1V

0

CIN = C

-20

-40

PSRR (dB)

-60

-80

0.01 0.1 1 10k 100k 1000k

10 100 1000 10000 100000 1000000

OUT1

OUT1

= C

= 1uF/X7R

OUT2

Frequency (Hz)

(Hz)

I

LOAD

I

= 100mA

LOAD

= 50mA

I

LOAD

= 10mA

0

0 50 100 150 200 250 300

Load Curre nt (mA)

POR Delay

10000

POR Delay Time (ms)

RT9012-FM

1000

100

10

1

0.1

0.01

0.0001 0.0010 0.0100 0.1000 1.0000

POR Setting Capacitance (uF)

DS9012-09 April 2011www.richtek.com

6

RT9012

4.8

V

IN

(V)

3.8

V

OUT2

(10mV/Div)

V

OUT1

(10mV/Div)

4.8

V

IN

(V)

3.8

V

OUT2

(10mV/Div)

Line Transient Response

RT9012-GS, Both I
V

= 3.8V to 4.8V

IN

= 1mA

LOAD

Time (100μs/Div)

Line Transient Response

RT9012-GS, Both I
V

= 3.8V to 4.8V

IN

LOAD

= 50mA

4.8

V

IN

(V)

3.8

V

OUT2

(10mV/Div)

V

OUT1

(10mV/Div)

4.8

V

IN

(V)

3.8

V

OUT2

(10mV/Div)

Line Transient Response

RT9012-GS, Both I
V

= 3.8V to 4.8V

IN

= 10mA

LOAD

Time (100μs/Div)

Line Transient Response

RT9012-GS, Both I
V

= 3.8V to 4.8V

IN

LOAD

= 100mA

V

OUT1

(10mV/Div)

I

OUT

(50mA/Div)

V

OUT1

(20mV/Div)

V

OUT2

(20mV/Div)

Time (100μs/Div)

Load Transient Response

RT9012-GS, I
V

= V

IN

EN

CIN = C

OUT1

= 10mA to 50mA

LOAD

= 4.3V

= C

= 1uF/X7R

OUT2

Time (250μs/Div)

V

OUT1

(10mV/Div)

I

OUT

(100mA/Div)

V

OUT1

(20mV/Div)

V

OUT2

(20mV/Div)

Time (100μs/Div)

Load Transient Response

RT9012-GS, I
V

= V

IN

EN

CIN = C

OUT1

= 10mA to 100mA

LOAD

= 4.3V

= C

= 1uF/X7R

OUT2

Time (250μs/Div)

DS9012-09 April 2011 www.richtek.com

7

RT9012

(5V/Div)

(1V/Div)

V

EN

(5V/Div)

RT9012-FM, V
I

= I

OUT1

OUT2

V

EN

RT9012-FM
Both I

LOAD

= 10mA

Start Up

= 5V

IN

= 50mA

V

V

OUT1

Time (5μs/Div)

Power-On

OUT2

(5V/Div)

(1V/Div)

150

100

50

EN Pin Shutdown Response

RT9012-FM, V
I

= I

OUT1

OUT2

V

EN

V

V

= 5V

IN

= 50mA

OUT2

OUT1

Time (50μs/Div)

Noise

RT9012-GS, No LOAD
V

= V

IN

C

IN

= 4.5V(By battery)

EN

= C

= C

OUT1

OUT2

= 1uF/X7R

V

OUT1

(1V/Div)

V

OUT2

(2V/Div)

POR

(5V/Div)

300

200

100

-100

Noise (μV/Div)

-200

-300

RT9012-GS, I
V

= V

IN

C

= C

IN

0

Time (10μs/Div)

= 50mA

LOAD

= 4.5V(By battery)

EN

= C

OUT2

= 1uF/X7R

OUT1

Noise

Noise (μV/Div)

0

-50

-100

-150

Time (10ms/Div)

Time (10ms/Div)

DS9012-09 April 2011www.richtek.com

8

Applications Information

RT9012

Like any low-dropout regulator, the external capacitors used

with the RT9012 must be carefully selected for regulator

stability and performance. Using a capacitor whose value

is > 1μF on the RT9012 input and the amount of

capacitance can be increased without limit. The input

capacitor must be located a distance of not more than 0.5

inch from the input pin of the IC and returned to a clean

analog ground. Any good quality ceramic or tantalum can

be used for this capacitor. The capacitor with larger value

and lower ESR (equivalent series resistance) provides

better PSRR and line-transient response.

The output capacitor must meet both requirements for

minimum amount of capacitance and ESR in all LDOs

application. The RT9012 is designed specifically to work

with low ESR ceramic output capacitor in space-saving

and performance consideration. Using a ceramic capacitor

whose value is at least 1μF with ESR is > 20mΩ on the

RT9012 output ensures stability. The RT9012 still works

well with output capacitor of other types due to the wide

stable ESR range. Figure 1. shows the curves of allowable

ESR range as a function of load current for various output

capacitor values. Output capacitor of larger capacitance

can reduce noise and improve load transient response,

stability, and PSRR. The output capacitor should be located

not more than 0.5 inch from the VOUT pin of the RT9012

and returned to a clean analog ground.

Thermal Considerations

Thermal protection limits power dissipation in RT9012.

When the operation junction temperature exceeds 170°C,

the OTP circuit starts the thermal shutdown function and

turns the pass element off. The pass element turn on again

after the junction temperature cools by 40°C. RT9012

lowers its OTP trip level from 170°C to 110°C when output

short circuit occurs (V

< 0.4V) as shown in Figure 2. It

OUT

limits IC case temperature under 100°C and provides

maximum safety to customer while output short circuit

occurring.

V

Short to GND

OUT

0.4V

V

OUT

I

OUT

TSD

°

170 C

110 C

OTP Trip Point

IC Temperature

°

110 C

80 C

°

°

Region of Stable C

100

10

ESR (Ω)

ESR (Ω)

OUT

OUT

1

0.1

ESR vs. Load Current

OUT

Unstable Range

Stable Range

RT9012-FM, V
C

= C

=

OUT1

= 1uF/X7R

C

IN

OUT2

IN

= 5V

Figure 2. Short Circuit Thermal Folded Back Protection

when Output Short Circuit Occurs (Patent)

For continuous operation, do not exceed absolute

maximum operation junction temperature 125°C. The

power dissipation definition in device is :

PD = (V

IN

− V

OUT

) x I

+ VIN x I

OUT

Q

The maximum power dissipation depends on the thermal

resistance of IC package, PCB layout, the rate of

0.01

Region of Stable C

Region of Stable C

0.001
0 50 100 150 200 250 300

Figure 1. Stable Cout ESR Range

Simulation Verify

Load Current (mA)

surroundings airflow and temperature difference between

junction to ambient. The maximum power dissipation can

be calculated by following formula :

P

Where T

D(MAX)

= ( T

J(MAX)

J(MAX)

temperature, T

A

− T

) /θ

A

JA

is the maximum operation junction

is the ambient temperature and the θ

JA

the junction to ambient thermal resistance.

DS9012-09 April 2011 www.richtek.com

is

9

RT9012

For recommended operating conditions specification of

RT9012, the maximum junction temperature is 125°C. The

junction to ambient thermal resistance (θJA is layout

dependent) for WDFN-8L 2x2 package is 108°C/W on the

standard JEDEC 51-3 single-layer thermal test board. The

maximum power dissipation at TA = 25°C can be calculated

by following formula :

P

= ( 125°C − 25°C ) / 108 = 0.926W for

D(MAX)

WDFN-8L 2x2 packages

The maximum power dissipation depends on operating

ambient temperature for fixed T

resistance θ

. For RT9012 packages, the Figure 3 of

JA

and thermal

J(MAX)

derating curves allows the designer to see the effect of

rising ambient temperature on the maximum power

allowed.

0.8

0.7

0.6

0.5

0.4

0.3

0.2

Power Dissipation (W)

0.1

0

0 25 50 75 100 125

WDFN-8L 2x2

Ambient Temperature

(°C)

Figure 3. Derating Curves for RT9012 Packages

10

DS9012-09 April 2011www.richtek.com

Outline Dimension

RT9012

D

E

A

A3

A1

D2

L

E2

SEE DETAIL A

1

e

b

2

1

1

2

DETAIL A

Pin #1 ID and Tie Bar Mark Options

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

but must be located within the zone indicated.

Dimensions In Millimeters Dimensions In Inches

Symbol

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 0.200 0.300 0.008 0.012

D 1.950 2.050 0.077 0.081

D2 1.000 1.250 0.039 0.049

E 1.950 2.050 0.077 0.081

E2 0.400 0.650 0.016 0.026

e 0.500 0.020

L 0.300 0.400

Richtek Technology Corporation

Headquarter

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

Hsinchu, Taiwan, R.O.C.

Tel: [phone] Fax: [phone]

0.012 0.016

W-Type 8L DFN 2x2 Package

Richtek Technology Corporation

Taipei Office (Marketing)

5F, No. 95, Minchiuan Road, Hsintien City

Taipei County, Taiwan, R.O.C.

Tel: [phone] Fax: [phone]

Email: [e-mail]

Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit

design, specification or other related things if necessary without notice at any time. No third party intellectual property infringement of the applications should be

guaranteed by users when integrating Richtek products into any application. No legal responsibility for any said applications is assumed by Richtek.

DS9012-09 April 2011 www.richtek.com

11