RT9167A-49CBR - Richtek Technology

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

Low-Noise, Fixed Output Voltage,

200mA/500mA LDO Regulator

General Description

The RT9167/A is a 200mA/500mA low dropout and

low noise micropower regulator suitable for portable

applications. The output voltages range from 1.5V to

5.0V in 100mV increments and 2% accuracy. The

RT9167/A is designed for use with very low ESR

capacitors. The output remains stable even with 1µF

ceramic output capacitor.

The RT9167/A uses and internal PMOS as the pass

device, which does not cause extra GND current in

heavy load and dropout conditions. The shutdown

mode of nearly zero operation current makes the IC

suitable for battery-power devices. Other features

include a reference bypass pin to improve low noise

performance, current limiting, and over temperature

protection.

Ordering Information

RT9167/A-  

Features

z Stable with Low-ESR Output Capacitor

z Low Dropout Voltage (220mV and 200mA)

z Low Operation Current - 80µ

µµ

µA Typical

z Shutdown Function

z Low Noise Output

z Low Temperature Coefficient

z Current and Thermal Limiting

z Custom Voltage Available

z SOT-25 and SOP-8 Packages

Applications

z Cellular Telephones

z Laptop, Notebook, and Palmtop Computers

z Battery-powered Equipment

z Hand-held Equipment

Pin Configurations

Part Number Pin Configurations

RT9167/A-CB

(Plastic SOT-25)

TOP VIEW

1. IN

2. GND

3. SHDN

4. BP

5. OUT

RT9167/A-CBR

(Plastic SOT-25)

TOP VIEW

1. OUT

2. GND

3. IN

4. SHDN

5. BP

RT9167/A-CS

(Plastic SOP-8)

TOP VIEW

Operating temperature range

C: Commercial standard

Package type

B : SOT-25 Type I

BR : SOT-25 Type II

S : SOP-8

Output voltage

15 : 1.5V

16 : 1.6V

49 : 4.9V

50 : 5.0V

500mA Output current

200mA Out

ut current

321

SHDN

OUT

GND

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

Marking Information

Part Number Marking

RT9167-15CB E0

RT9167-16CB E1

RT9167-17CB E2

RT9167-18CB E3

RT9167-19CB E4

RT9167-20CB E5

RT9167-21CB E6

RT9167-22CB E7

RT9167-23CB E8

RT9167-24CB E9

RT9167-25CB EA

RT9167-26CB EB

RT9167-27CB EC

RT9167-28CB ED

RT9167-29CB EE

RT9167-30CB EF

RT9167-31CB EG

RT9167-32CB EH

RT9167-33CB EJ

RT9167-34CB EK

RT9167-35CB EL

RT9167-36CB EM

RT9167-37CB EN

RT9167-38CB EP

RT9167-39CB EQ

RT9167-40CB ER

RT9167-41CB ES

RT9167-42CB ET

RT9167-43CB EU

RT9167-44CB EV

RT9167-45CB EW

RT9167-46CB EX

RT9167-47CB EY

RT9167-48CB EZ

RT9167-49CB AR

Part Number Marking

RT9167-50CB AS

RT9167A-15CB J0

RT9167A-16CB J1

RT9167A-17CB J2

RT9167A-18CB J3

RT9167A-19CB J4

RT9167A-20CB J5

RT9167A-21CB J6

RT9167A-22CB J7

RT9167A-23CB J8

RT9167A-24CB J9

RT9167A-25CB JA

RT9167A-26CB JB

RT9167A-27CB JC

RT9167A-28CB JF

RT9167A-29CB JE

RT9167A-30CB JD

RT9167A-31CB JG

RT9167A-32CB JH

RT9167A-33CB JJ

RT9167A-34CB JK

RT9167A-35CB JL

RT9167A-36CB JM

RT9167A-37CB JN

RT9167A-38CB JP

RT9167A-39CB JQ

RT9167A-40CB JR

RT9167A-41CB JS

RT9167A-42CB JT

RT9167A-43CB JU

RT9167A-44CB JV

RT9167A-45CB JW

RT9167A-46CB JX

RT9167A-47CB JY

RT9167A-48CB JZ

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

Part Number Marking

RT9167A-49CB CA

RT9167A-50CB CB

RT9167-15CBR I0

RT9167-16CBR I1

RT9167-17CBR I2

RT9167-18CBR I3

RT9167-19CBR I4

RT9167-20CBR I5

RT9167-21CBR I6

RT9167-22CBR I7

RT9167-23CBR I8

RT9167-24CBR I9

RT9167-25CBR IA

RT9167-26CBR IB

RT9167-27CBR IC

RT9167-28CBR ID

RT9167-29CBR IE

RT9167-30CBR IF

RT9167-31CBR IG

RT9167-32CBR IH

RT9167-33CBR IJ

RT9167-34CBR IK

RT9167-35CBR IL

RT9167-36CBR IM

RT9167-37CBR IN

RT9167-38CBR IP

RT9167-39CBR IQ

RT9167-40CBR IR

RT9167-41CBR IS

RT9167-42CBR IT

RT9167-43CBR IU

RT9167-44CBR IV

RT9167-45CBR IW

RT9167-46CBR IX

RT9167-47CBR IY

RT9167-48CBR IZ

RT9167-49CBR CY

Part Number Marking

RT9167-50CBR CZ

RT9167A-15CBR K0

RT9167A-16CBR K1

RT9167A-17CBR K2

RT9167A-18CBR K3

RT9167A-19CBR K4

RT9167A-20CBR K5

RT9167A-21CBR K6

RT9167A-22CBR K7

RT9167A-23CBR K8

RT9167A-24CBR K9

RT9167A-25CBR KA

RT9167A-26CBR KB

RT9167A-27CBR KC

RT9167A-28CBR KD

RT9167A-29CBR KE

RT9167A-30CBR KF

RT9167A-31CBR KG

RT9167A-32CBR KH

RT9167A-33CBR KJ

RT9167A-34CBR KK

RT9167A-35CBR KL

RT9167A-36CBR KM

RT9167A-37CBR KN

RT9167A-38CBR KP

RT9167A-39CBR KQ

RT9167A-40CBR KR

RT9167A-41CBR KS

RT9167A-42CBR KT

RT9167A-43CBR KU

RT9167A-44CBR KV

RT9167A-45CBR KW

RT9167A-46CBR KX

RT9167A-47CBR KY

RT9167A-48CBR KZ

RT9167A-49CBR CC

RT9167A-50CBR CD

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

Pin Description

Pin Name Pin Function

IN Input

GND Ground

SHDN Active Low Shutdown Input

BP Reference Noise Bypass

OUT Output

Function Block Diagram

Typical Application Circuit

MOS Driver

Current-Limit

and

Thermal

Protection

Shutdown

and

Logic Control

VREF

Error Amp

GND

OUT

SHDN

RT9167

OFF

GND

IN OUT VOU T

CBP

10nF

COUT

1µF

VIN

CIN

1µF

SHDN BP

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

Absolute Maximum Ratings

z Input Voltage 8V

z Power Dissipation, PD @ TA = 25°C

SOT-25 0.25W

SOP-8 0.625W

z Operating Junction Temperature Range −40°C to 125°C

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

z Package Thermal Resistance

SOT-25, θJA 250°C/W

SOP-8, θJA 160°C/W

z Lead Temperature (Soldering, 5 sec.) 260°C

Electrical Characteristics

(VIN = 5.0V, CIN = 1µF, COUT = 1µF, TA = 25°C, unless otherwise specified)

Parameter Symbol Test Conditions Min Typ Max Units

2.9 -- 7

Input Voltage Range VIN IL = 50mA 2.7 -- 7 V

Output Voltage Accuracy ∆VOUT IL = 1mA -2 -- +2 %

RT9167 200 -- --

Maximum Output

Current RT9167A IMAX 500 -- -- mA

RT9167 -- 300 --

Current Limit RT9167A ILIMIT RLOAD = 1Ω-- 700 -- mA

RT9167/A No Load -- 80 150

RT9167 IOUT = 200mA -- 90 150

GND Pin Current

RT9167A

IOUT = 500mA -- 90 150

µA

RT9167/A IOUT = 1mA -- 1.1 5

RT9167/A IOUT = 50mA -- 55 100

RT9167/A IOUT = 200mA -- 220 300

Dropout Voltage (Note)

(VOUT(Nominal)≥3.0V

Version)

RT9167A

VDROP

IOUT = 500mA -- 600 750

Line Regulation ∆VLINE VIN = (VOUT+0.15) to 7V, IOUT = 1mA -0.2 -- +0.2 %/V

RT9167 IOUT = 0mA to 200mA -- 0.01 0.04

Load Regulation RT9167A ∆VLOAD IOUT = 0mA to 500mA -- 0.01 0.04 %/mA

SHDN Input High Threshold VIH VIN = 3V to 5.5V 1.6 -- -- V

SHDN Input Low Threshold VIL VIN = 3V to 5.5V -- -- 0.4 V

SHDN Bias Current ISD -- -- 100 nA

Shutdown Supply Current IGSD VOUT = 0V -- 0.01 1 µA

Thermal Shutdown Temperature TSD -- 155 -- °C

Output Noise eNO CBP = 10nF, COUT = 10µF-- 350 -- nV Hz

Ripple Rejection PSRR F = 100Hz, CBP = 10nF, COUT = 10µF-- 58 -- dB

Notes: Dropout voltage definition: VIN - VOUT when VOUT is 50 mV below the value of VOUT at VIN = VOUT + 0.5V

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

Typical Operating Charateristics

Output Voltage vs. Temp.

3.25

3.26

3.27

3.28

3.29

3.30

3.31

3.32

3.33

-50 -25 0 25 50 75 100 125 150

Output Voltage (V)

Temperature ( )

VOUT = 3.3V

°C

GND Current vs. Temp.

105

120

-50 -25 0 25 50 75 100 125 150

Temperature ( )

GND Current ( A)

VOUT = 3.3V

Current Limit vs. Temp.

100

200

300

400

500

600

700

800

900

-50 -25 0 25 50 75 100 125 150

Current Limit (mA)

Temperature ( )

RT9167A

VOUT = 3.3V

Current Limit vs. Temp.

120

180

240

300

360

420

480

-50 -25 0 25 50 75 100 125 150

Current Limit (mA)

Temperature ( )

RT9167

VOUT = 3.3V

PSRR

10 100 1000 10000 100000 100000

Frequency (KHz)

PSRR (dB)

ILOAD = 1mA, COUT = 4.7µF

VOUT = 3.3V, CBP = 10nF

10 100 1K 10K 100K 1M

Dropout Voltage vs. Output Current

100

150

200

250

300

0 25 50 75 100 125 150 175 200

Output Current (mA)

Dropout Voltage (V)

VOUT = 3.3V

85°C

25°C

-40°C

(mV)

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

≈

≈≈

≈

≈≈

≈

-50

-20

Load Transient Response

Time

(

S/Div

)

Load Current

(mA)

Output Voltage

Deviation (mV)

COUT = 1µF

CIN = 10µF

CBP = 10nF

VOUT = 3.0V

VIN = 4V

≈

≈≈

≈

≈≈

≈

-50

-20

Load Transient Response

Time

(

S/Div

)

Load Current

(mA)

Output Voltage

Deviation (mV)

COUT = 4.7µF

CIN = 10µF

CBP = 10nF

VOUT = 3.0V

VIN = 4V

↓

≈

≈≈

≈

≈≈

≈

150

100

-50

Line Transient Response

Time (1mS/Div)

Input Voltage (V) Output Voltage (mV)

COUT = 1µF

VOUT = 3.0V

Loading = 1mA

CBP = 10nF

↓

≈

≈≈

≈

≈≈

≈

150

100

-50

Line Transient Response

Time

(

500

S/Div

)

Input Voltage (V) Output Voltage (mV)

COUT = 4.7µF

VOUT = 3.0V

Loading = 1mA

CBP = 10nF

↓

≈

≈≈

≈

≈≈

≈

150

100

-50

Line Transient Response

Time (1mS/Div)

Input Voltage (V) Output Voltage (mV)

COUT = 1µF

VOUT = 3.0V

Loading = 50mA

CBP = 10nF

↓

≈

≈≈

≈

≈≈

≈

-20

Line Transient Response

Time

(

500

S/Div

)

Input Voltage (V) Output Voltage (mV)

COUT = 4.7µF

VOUT = 3.0V

Loading = 50mA

CBP = 10nF

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

Applications Guides

Capacitor Selection and Regulator Stability

Like any low-dropout regulator, the external capacitors

used with the RT9167/A must be carefully selected for

regulator stability and performance.

Using a capacitor whose value is > 1µF on the

RT9167/A 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" 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 RT9167/A 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 1uF with

ESR is > 5mΩ on the RT9167/A output ensures

stability. The RT9167/A still works well with output

capacitor of other types due to the wide stable ESR

range. Fig.1 shows the curves of allowable ESR range

as a function of load current for various output

voltages and 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" from the VOUT pin of the RT9167/A and returned

to a clean analog ground.

Note that some ceramic dielectrics exhibit large

capacitance and ESR variation with temperature. It

may be necessary to use 2.2µF or more to ensure

stability at temperatures below -10°C in this case. Also,

tantalum capacitors, 2.2µF or more may be needed to

maintain capacitance and ESR in the stable region for

strict application environment.

Tantalum capacitors maybe suffer failure due to surge

current when it is connected to a low-impedance

source of power (like a battery or very large capacitor).

If a tantalum capacitor is used at the input, it must be

guaranteed to have a surge current rating sufficient for

the application by the manufacture.

Use a 10nF bypass capacitor at BP for low output

voltage noise. The capacitor, in conjunction with an

internal 200KΩ resistor, which connects bypass pin

and the band-gap reference, creates an 80Hz low-

pass filter for noise reduction. Increasing the

capacitance will slightly decrease the output noise,

but increase the start-up time. The capacitor

connected to the bypass pin for noise reduction must

have very low leakage. This capacitor leakage

current causes the output voltage to decline by a

proportional amount to the current due to the voltage

drop on the internal 200KΩ resistor. Fig. 2 shows the

power on response.

Fig. 1

COUT = 4.7µF

COUT = 1µF

Ω

ion of Stable C

OUT

ESR vs. Load Current

0 40 80 120 160 200

Load Current (mA)

COUT ESR (Ω)

100

0.001

0.01

0.1

(mΩ)

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

Load-Transient Considerations

The RT9167/A load-transient response graphs (see

Typical Operating Characteristics) show two

components of the output response: a DC shift from

the output impedance due to the load current

change, and the transient response. The DC shift is

quite small due to the excellent load regulation of the

IC. Typical output voltage transient spike for a step

change in the load current from 0mA to 50mA is tens

mV, depending on the ESR of the output capacitor.

Increasing the output capacitor’s value and

decreasing the ESR attenuates the overshoot.

Shutdown Input Operation

The RT9167/A is shutdown by pulling the SHDN

input low, and turned on by driving the input high. If

this feature is not to be used, the SHDN input should

be tied to VIN to keep the regulator on at all times

(the SHDN input must not be left floating).

To ensure proper operation, the signal source used to

drive the SHDN input must be able to swing above and

below the specified turn-on/turn-off voltage thresholds

which guarantee an ON or OFF state (see Electrical

Characteristics). The ON/OFF signal may come from

either CMOS output, or an open-collector output with

pull-up resistor to the RT9167/A input voltage or

another logic supply. The high-level voltage may

exceed the RT9167/A input voltage, but must remain

within the absolute maximum ratings for the SHDN pin.

Internal P-Channel Pass Transistor

The RT9167/A features a typical 1.1Ω P-channel

MOSFET pass transistor. It provides several

advantages over similar designs using PNP pass

transistors, including longer battery life. The P-channel

MOSFET requires no base drive, which reduces

quiescent current considerably. PNP-based regulators

waste considerable current in dropout when the pass

transistor saturates. They also use high base-drive

currents under large loads. The RT9167/A does not

suffer from these problems and consume only 80µA of

quiescent current whether in dropout, light-load, or

heavy-load applications.

Input-Output (Dropout) Voltage

A regulator’s minimum input-output voltage

differential (or dropout voltage) determines the

lowest usable supply voltage. In battery-powered

systems, this will determine the useful end-of-life

battery voltage. Because the RT9167/A uses a P-

channel MOSFET pass transistor, the dropout

voltage is a function of drain-to-source on-resistance

[RDS(ON)] multiplied by the load current.

Reverse Current Path

The power transistor used in the RT9167/A has an

inherent diode connected between the regulator

input and output (see Fig.3). If the output is forced

above the input by more than a diode-drop, this

diode will become forward biased and current will

flow from the VOUT terminal to VIN. This diode will

also be turned on by abruptly stepping the input

voltage to a value below the output voltage. To

prevent regulator mis-operation, a Schottky diode

should be used in any applications where

input/output voltage conditions can cause the

internal diode to be turned on (see Fig.4). As shown,

the Schottky diode is connected in parallel with the

internal parasitic diode and prevents it from being

turned on by limiting the voltage drop across it to

about 0.3V. < 100 mA to prevent damage to the part.

10.0 15.005.0

CBP = 10nF

Time

(

)

Fig. 2

CBP = 1nF

Volta

(

0.5V / DIV

)

VOUT = 3.0V

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

Current Limit and Thermal Protection

The RT9167 includes a current limit which monitors

and controls the pass transistor’s gate voltage limiting

the output current to 300mA Typ. (700mA Typ. for

RT9167A). Thermal-overload protection limits total

power dissipation in the RT9167/A. When the junction

temperature exceeds TJ = +155°C, the thermal sensor

signals the shutdown logic turning off the pass

transistor and allowing the IC to cool. The thermal

sensor will turn the pass transistor on again after the

IC’s junction temperature cools by 10°C, resulting in a

pulsed output during continuous thermal-overload

conditions. Thermal-overloaded protection is designed

to protect the RT9167/A in the event of fault conditions.

Do not exceed the absolute maximum junction-

temperature rating of TJ = +150°C for continuous

operation. The output can be shorted to ground for an

indefinite amount of time without damaging the part by

cooperation of current limit and thermal protection.

Operating Region and Power Dissipation

The maximum power dissipation of RT9167/A

depends on the thermal resistance of the case and

circuit board, the temperature difference between the

die junction and ambient air, and the rate of airflow.

The power dissipation across the device is P = IOUT

(VIN - VOUT). The maximum power dissipation is:

PMAX = (TJ - TA) /θJA

where TJ - TA is the temperature difference between

the RT9167/A die junction and the surrounding

environment, θJA is the thermal resistance from the

junction to the surrounding environment. The GND pin

of the RT9167/A performs the dual function of

providing an electrical connection to ground and

channeling heat away. Connect the GND pin to ground

using a large pad or ground plane.

Fig. 3

VIN VOU T

Fig. 4

VIN VOU T

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

Package Information

Dimensions In Millimeters Dimensions In Inches

Symbol Min Max Min Max

A 0.889 1.295 0.035 0.051

A1 0.000 0.152 0.000 0.006

B 1.397 1.803 0.055 0.071

b 0.356 0.559 0.014 0.022

C 2.591 2.997 0.102 0.118

D 2.692 3.099 0.106 0.122

e 0.838 1.041 0.033 0.041

H 0.102 0.254 0.004 0.010

L 0.356 0.610 0.014 0.024

SOT- 25 Surface Mount Package

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

Dimensions In Millimeters Dimensions In Inches

Symbol Min Max Min Max

A 4.801 5.004 0.189 0.197

B 3.810 3.988 0.150 0.157

C 1.346 1.753 0.053 0.069

D 0.330 0.508 0.013 0.020

F 1.194 1.346 0.047 0.053

H 0.178 0.254 0.007 0.010

I 0.102 0.254 0.004 0.010

J 5.791 6.198 0.228 0.244

M 0.406 1.270 0.016 0.050

8–Lead SOP Plastic Package

D I

RT9167/A

DS9167/A-10 July 2001 www.richtek-ic.com.tw

RT9167/A

www.richtek-ic.com.tw DS9167/A-10 July 2001

RICHTEK TECHNOLOGY CORP.

Headquarter

6F, No. 35, Hsintai Road, Chupei City

Hsinchu, Taiwan, R.O.C.

Tel: (8863)5510047 Fax: (8863)5537749

RICHTEK TECHNOLOGY CORP.

Taipei Office (Marketing)

8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City

Taipei County, Taiwan, R.O.C.

Tel: (8862)89191466 Fax: (8862)89191465

Email: marketing@richtek-ic.com.tw