RT9183H-PM5 - Richtek Technology

RT9183

DS9183-21 October 2015 www.richtek.com

Ultra Low Dropout 1.5A Linear Regulator

General Description

The RT9183 series are high performance linear voltage

regulators that provide ultra low-dropout voltage, high

output current with low ground current. It operates from

an input of 2.3V to 5.5V and provides output current up to

1.5A thus is suitable to drive digital circuits requiring low

voltage at high currents.

The RT9183 ha s superior regulation over variations in line

and load. Also it provides fa st respond to step changes in

load. Other features include over-current and over-

temperature protection. The adjustable version ha s enable

pin to reduce power consumption in shutdown mode.

The devices are available in fixed output voltages of 1.2V

to 3.3V with 0.1V per step and as an adjustable device

with a 0.8V reference voltage. The RT9183 regulators are

available in 3-lead SOT-223 and TO-263 packages (fixed

output only for the 3-lead option). Also available are 5-

lead TO-263, TO-252 and fused SOP-8 packages with two

external resistors to set the output voltage ranges from

0.8V to 4.5V.

Features



330mV Dropout @ 1.5A



380μμ

μμ

μA Low Ground Pin Current



Excellent Line and Load Regulation



0.1μμ

μμ

μA Quiescent Current in Shutdown Mode



Guaranteed 1.5A Output Current



Fixed Output Voltages : 1.2V to 3.3V



Adjustable Output Voltage from 0.8V to 4.5V



Over-Temperature/Over-Current Protection



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

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.

Ordering Information

Applications

Battery-Powered Equipment

Mother Board/Gra phic Card

Peripheral Cards

PCMCIA Card

RT9183 Package Type

G : SOT-223

GF : SOT-223 (F-Type)

S : SOP-8

L: TO-252

LF : TO-252 (F-Type)

M : TO-263

M5 : TO-263-5

Output Voltage

Defauit : Adjustable

12 : 1.2V

13 : 1.3V

32 : 3.2V

33 : 3.3V

Only for SOP-8 and TO-263-5

H : Chip Enable High

L : Chip Enable Low

Lead Plating System

P : Pb Free

G : Green (Halogen Free and Pb Free)

Marking Information

For marking information, conta ct our sales representative

directly or through a Richtek distributor located in your

area.

RT9183

2DS9183-21 October 2015www.richtek.com

Typical Application Circuit

Figure 1. 3.3V to 2.5V Regulator

Figure 2. Adjustable Operation

)Volts

(1 0.8VOUT  Note: The value of R2 should be less

than 80k to maintain

regulation.

(TOP VIEW)

Pin Configurations

TO-263

231

VIN

GND(TAB)

VOUT

TO-263-5

423 51

EN GND(TAB)

VIN VOUT ADJ

SOP-8

GND

VIN

VOUT

ADJ GND

GND

TO-252 (F-Type)

231

VOUT

(TAB)

GND VIN

TO-252

231

GND

(TAB)

VIN VOUT

SOT -223 (F-Type)

231

GND VOUT

(TAB) VIN

SOT-223

231

VIN GND

(TAB) VOUT

2.5V, 1.5A

(SOT-223 & TO-263 & TO-252)

RT9183

VIN VOUT

GND

VOUT

VIN = 3.3V

CIN COUT

10µF 10µF

(SOP-8 & TO-263-5)

VIN VOUT

GND

ADJ

RT9183 VOUT

VIN

CIN COUT

C10µF

0.1µF 10µF

Enable

RT9183

DS9183-21 October 2015 www.richtek.com

Figure 3. Fixed Operation with SOP-8 and TO-263-5 pa ckages

Functional Pin Description

Pin Name Pin Function

EN Chip Enable Co nt rol Input.

Note t hat t he device wi ll be in the unstable state if the pin is not connect ed.

VIN Supply Input.

GND Common Ground.

VOUT Regulator Output.

ADJ

The output voltage is set by the i nt ernal f eedback r esi stors when this pin

grounded. If ex ternal fe edback re s ist or s are a ppli ed, the ou tpu t vol tage wil l be :

VOUT = 0.8  (1 + ) Volts

Function Block Diagram

VIN VOUT

EN GND

ADJ

(SOP-8 & TO-263-5)

RT9183 VOUTVIN

CIN

COUT

C10µF0.1µF 10µF

Enable

Thermal

Shutdown

VOUT

Shutdown

Logic

GND

Output Mode

Comparator

ADJ

VIN

Error

Amplifier

0.8V

Reference

Current Limit

Sensor +

100mV

RT9183

4DS9183-21 October 2015www.richtek.com

Electrical Characteristics

(VIN = VOUT + 0.7V, CIN = COUT = 10μF (Ceramic), TA = 25°C unless otherwise specified)

Recommended Operating Conditions (Note 4)

Supply Input Voltage------------------------------------------------------------------------------------------------------ 2.3V to 5.5V

Junction T emperature Range-------------------------------------------------------------------------------------------- −40°C to 125°C

Ambient T emperature Range-------------------------------------------------------------------------------------------- −40°C to 85°C

Absolute Maximum Ratings (Note 1)

Supply Input Voltage------------------------------------------------------------------------------------------------------ 7V

Pa ckage Thermal Re sistance (Note 2)

SOT-223, θJA ---------------------------------------------------------------------------------------------------------------- 115°C/W

SOT-223, θJC --------------------------------------------------------------------------------------------------------------- 15°C/W

SOT-223 (F-Type), θJA ---------------------------------------------------------------------------------------------------- 135°C/W

SOT-223 (F-T ype), θJC ---------------------------------------------------------------------------------------------------- 17°C/W

SOP-8, θJA ------------------------------------------------------------------------------------------------------------------ 125°C/W

SOP-8, θJC------------------------------------------------------------------------------------------------------------------ 20°C/W

TO-252, θJA ----------------------------------------------------------------------------------------------------------------- 68°C/W

TO-252, θJC ----------------------------------------------------------------------------------------------------------------- 8°C/W

TO-252 (F-T ype), θJA ------------------------------------------------------------------------------------------------------ 75°C/W

TO-252 (F-T ype), θJC ------------------------------------------------------------------------------------------------------ 15°C/W

TO-263, θJA ----------------------------------------------------------------------------------------------------------------- 45°C/W

TO-263, θJC ----------------------------------------------------------------------------------------------------------------- 8°C/W

Power Dissipation, PD@TA = 25°C

SOT-223 --------------------------------------------------------------------------------------------------------------------- 0.87W

SOT-223 (F-Type)---------------------------------------------------------------------------------------------------------- 0.74W

SOP-8------------------------------------------------------------------------------------------------------------------------ 0.8W

TO-252 ----------------------------------------------------------------------------------------------------------------------- 1.471W

TO-252 (F-Type) ----------------------------------------------------------------------------------------------------------- 1.333W

TO-263 ----------------------------------------------------------------------------------------------------------------------- 2.22W

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

Junction T emperature----------------------------------------------------------------------------------------------------- 150°C

Storage T emperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C

ESD Susceptibility (Note 3)

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

MM (Ma chine Mode) ------------------------------------------------------------------------------------------------------ 200V

Parameter Symbol Test Conditions Min Typ Max Unit

Outp ut Vol t age A ccur acy

( Fi xed Output Vol tage) VOUT I

OUT = 1 0mA 2 0 2 %

Outp ut Volt age Range (Adjustable) VOUT_ADJ 0.8 -- 4.5 V

Quiescent Current (Note 5) IQ I

OUT = 0mA , E nable - - 380 500 A

Standby Current (Note 6) ISTBY V

IN = 5 .5V , Shutdo wn - - 0. 1 1 A

RT9183

DS9183-21 October 2015 www.richtek.com

Parameter Symbol Test Conditions Min Typ Max Unit

Current Limit ILIM 2 3.2 4.2 A

Dropout Voltage (Note 7) VDROP IOUT = 0.5A -- 110 300 mV

IOUT = 1.0A -- 220 400

IOUT = 1.5A -- 330 500

Line Regulation VLINE VOUT + 0. 7V  VIN  5.5V

IOUT = 10mA -- 0.035 0.18 %/V

Load Regulation (Note 8)

(F ixed Output V oltage) VLOAD 1mA < IOUT < 1.5A -- 22 45 mV

Thermal Shutdown Temperature TSD -- 170 -- C

Thermal Shutdown Hysteresis TSD -- 30 -- C

E N Thr eshold Voltage Logic-Low VIL V

IN = 5.5V -- -- 0.6 V

Logic-High VIH V

IN = 5.5V (Note 9) 1.2 -- --

Enable Pin Current IEN V

IN = 5.5V, Enable -- 0.1 1 A

ADJ

Reference Voltage Tolerance VREF 0.784 0.8 0.816 V

Adjust Pin C urrent IADJ V

ADJ = VREF -- 10 100 nA

A djust P in Thr eshold VTH(ADJ) 0.05 0.1 0.2 V

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 af fect device relia bility.

Note 2. θJA is measured in natural convection (still air) at TA = 25°C with the component mounted on a low effective

thermal conductivity test board of JEDEC 51-3 thermal measurement standard. And the copper area of PCB

layout is 4mm x 2.5mm on SOT-223, 10mm x 10mm on TO-252, 14mm x 14mm on TO-263 for thermal

measurement.

Note 3. Devices are ESD sensitive. Ha ndling precaution is recommended.

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

Note 5. 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 6. Standby current is the input current drawn by a regulator when the output voltage is disabled by a shutdown

signal (VEN >1.8V ). It is measured with VIN = 5.5V.

Note 7. The dropout voltage is defined as VIN − VOUT, which is measured when VOUT is VOUT(NORMAL) − 100mV.

Note 8. Regulation is mea sured at con stant junction temperature by using a 20ms current pulse. Devices are te sted for

load regulation in the loa d range from 10mA to 1.5A.

Note 9. The EN threshold should be higher than VIH for turning on.

RT9183

6DS9183-21 October 2015www.richtek.com

Typical Operating Characteristics

Output Voltage vs. Temperature

1.7

1.75

1.8

1.85

1.9

-50 -25 0 25 50 75 100 125

Temperature

Output Voltage (V)

(°C)

RT9183H-18xS

VIN = 5V, RL =

CIN = COUT = 10μF (Ceramic,Y5V)



Output Voltage vs. Temperature

2.4

2.45

2.5

2.55

2.6

-50 -25 0 25 50 75 100 125

Temperature

Output Voltage (V)

VIN = 5V, RL =

CIN = COUT = 10μF (Ceramic,Y5V)

(°C)

RT9183-25xG



Quiescent Current vs. Temperature

300

320

340

360

380

400

-50 -25 0 25 50 75 100 125

Temperature

Quiescent Current (uA) 1

VIN = 5V, RL =

CIN = COUT = 10μF

(Ceramic,Y5V) RT9183H-18xS

(°C)



Quie scent Current vs. Temperature

300

320

340

360

380

400

-50 -25 0 25 50 75 100 125

Temperature

Quiescent Current (uA) 1

(°C)

VIN = 5V, RL =

CIN = COUT = 10μF

(Ceramic,Y5V) RT9183-25xG



Current Limit vs. Temperature

3.2

3.4

3.6

3.8

-50 -25 0 25 50 75 100 125

Temperature

Current Limit (A)

(°C)

VIN = 5V, CIN = COUT = 10μF(Ceramic,Y5V)

RT9183-25xG

Current Lim it vs. Temperature

3.2

3.4

3.6

3.8

-50 -25 0 25 50 75 100 125

Temperature

Current Limit (A)

(°C)

VIN = 5V, CIN = COUT = 10μF(Ceramic,Y5V)

RT9183L-33xM5

RT9183

DS9183-21 October 2015 www.richtek.com

Load Transient Response

Time (100μs/Div)

-50

Load

Current (A)

Output Voltage

Deviation(mV)

RT9183H-18xS

COUT = 47uF/Low ESR, ILOAD = 1mA to 1.5A

Load Transient Response

RT9183H-18xS

Time (100μs/Div)

COUT = 47μF/Low ESR, ILOAD = 1mA to 750mA

Load

Current (A)

Output Voltage

Deviation(mV)

-20

0.5

Dropout Voltage

100

200

300

400

500

0 0.3 0.6 0.9 1.2 1.5

Load Current (A)

Dropout Voltage (mV)

TJ = +25°C

TJ = 125°C

TJ = -40°C

RT9183L-33xM5

Dropout Voltage vs. Load Current

Dropout Voltage

100

200

300

400

500

0 0.3 0.6 0.9 1.2 1.5

Load Current (A)

Dropout Voltage (mV) 1

TJ = +25°C

TJ = 125°C

TJ = -40°C

RT9183-25xG

Dropout Voltage vs. Load Current

Dropout Voltage vs . Loa d Current

100

200

300

400

0 0.3 0.6 0.9 1.2 1.5

Load Cur rent (A)

Dropout Voltage (mV)

TJ= 125°C

TJ= 25°C

TJ= -40°C

RT9183H-xS

VOUT = 3.3V

Load Transient Regulation

Time (100μs/Div)

COUT = 47μF/Low ESR

Output Voltage

Deviation(mV)Load Current (mA)

ILOAD = 1mA to 750mA

500

RT9183-12xGF

RT9183

8DS9183-21 October 2015www.richtek.com

Line Transient Regulation

Time (100μs/Div)

Input Voltage

Deviation(V)

Output Voltage

Deviation(mV)

COUT = 47μF/Low ESR

ILOAD = 100mA

RT9183-12xGF

Time (100μs/Div)

RT9183H-18xS

COUT = 47μF/Low ESR, ILOAD = 100mA

Input Voltage

Deviation(V)

Output Voltage

Deviation(mV)

Line Transient Response

-10

EN Pin Shutdown Threshold vs . Te mp erature

0.7

0.8

0.9

1.1

-50 -25 0 25 50 75 100 125

Temperature

Shutdown Threshold Voltage (V) 1

RT9183L-33xM5

VOUT Off to On

VOUT On to Off

(°C)

EN Pin Threshold Voltage (V)

EN Pin Threshold Voltage vs. Temperature

Reference Voltage vs. Temperature

0.75

0.77

0.79

0.81

0.83

0.85

-50 -25 0 25 50 75 100 125

Temperature

Reference Voltage (V)

(°C)

VIN = 5V,CIN = COUT = 10μF (Electrolysis)

RT9183H-xS

EN Pin Shutdown Response

RT9183H-18xS

Time (500μs/Div)

CIN = COUT = 10μF (Ceramic,Y5V)

ILOAD = 100mA, VIN = 5V, TA =25°C

Voltage (V)

Output

Voltage (V)

PSRR

-80

-60

-40

-20

10 100 1000 10000 100000 1000000

Frequency (Hz)

PSRR(dB)

Loading = 1A

Loading = 800mA

Loading = 100mA

Loading = 10mA

RT9183

DS9183-21 October 2015 www.richtek.com

Input Capacitor

An input capacitance of ≅10μF is required between the

device input pin and ground directly (the amount of the

capacitance may be increased without limit). The input

capa citor MUST be located less than 1 cm from the device

to a ssure input stability (see PCB Layout Section). A lower

ESR capacitor allows the use of less capacitance, while

higher ESR type (like aluminum electrolytic) require more

capacitance.

Capacitor types (aluminum, ceramic and tantalum) can

be mixed in parallel, but the total equivalent input

capacitance/ESR must be defined as above to stable

operation.

There are no requirements for the ESR on the input

ca pacitor, but tolerance and temperature coefficient must

be considered when selecting the ca pacitor to ensure the

capacitance will be≅10μF over the entire operating

temperature range.

Output Ca pa citor

The RT9183 is designed specifically to work with very

small ceramic output capacitors. The recommended

minimum capacitance (temperature characteristics X7R

or X5R) are 10μF to 47μF ra nge with 1mΩ to 25mΩ range

ceramic capacitors between each LDO output and GND

for tra nsient stability , but it may be increa sed without limit.

Higher ca pacitance values help to improve tra nsient.

The output capa citor's ESR is critical because it f orms a

zero to provide phase lead which is required for loop

stability.

Application Information

Like any low-dropout regulator, the RT9183 series requires

input and output decoupling ca pacitors. These ca pa citors

must be correctly selected for good performance (see

Ca pacitor Characteristics Section). Plea se note that linear

regulators with a low dropout voltage have high internal

loop gains which require care in guarding against

oscillation caused by insufficient decoupling ca pacitance.

No Load Stability

The device will remain stable and in regulation with no

external load. This is speci ally important in CMOS RAM

keep-alive a pplications.

Input-Output (Dropout) Voltage

A regulator's minimum input-to-output voltage differential

(dropout voltage) determines the lowest usable supply

voltage. In battery-powered systems, this determines the

useful end-of-life battery voltage. Because the device uses

a PMOS, its dropout voltage is a function of drain-to-

source on-resistance, RDS(ON), multiplied by the load

current :

VDROPOUT = VIN − VOUT = RDS(ON) × IOUT

Current Limit

The RT9183 monitors and controls the PMOS' gate

voltage, minimum limiting the output current to 2A . The

output can be shorted to ground for a n indefinite period of

time without damaging the part.

Short-Circuit Protection

The device is short circuit protected a nd in the event of a

pea k over-current condition, the short-circuit control loop

will ra pidly drive the output PMOS pass element off. Once

the power pa ss element shuts down, the control loop will

ra pidly cycle the output on and off until the average power

dissipation causes the thermal shutdown circuit to

respond to servo the on/off cycling to a lower frequency.

Plea se refer to the section on thermal information for power

dissipation calculations.

Ca paa citor Characteristics

It is important to note that capacitance tolerance and

variation with temperature must be taken into consideration

when selecting a ca pa citor so that the minimum required

a mount of ca pa citance is provided over the full operating

temperature range. In general, a good tantalum ca pacitor

will show very little ca pacitance variation with temperature,

but a cera mic may not be as good (depending on dielectric

type). Aluminum electrolytics also typically have large

temperature variation of ca pacitance value.

RT9183

10 DS9183-21 October 2015www.richtek.com

Equally important to consider is a ca pacitor's ESR change

with temperature: this is not an issue with ceramics, as

their ESR is extremely low. However , it is very importa nt

in tantalum and aluminum electrolytic capacitors. Both

show increasing ESR at colder temperatures, but the

increa se in aluminum ele ctrolytic ca pa citors is so severe

they may not be feasible for some applications.

Ceramic :

For values of capacitance in the 10μF to 100μF range,

ceramics are usually larger and more costly than tantalums

but give superior AC performance for by-passing high

frequency noise because of very low ESR (typically less

than 10mΩ). However, some dielectric types do not have

good ca pa citance chara cteristics a s a function of voltage

and temperature.

Z5U and Y5V dielectric ceramics have capacitance that

drops severely with a pplied voltage. A typical Z5U or Y5V

capa citor can lose 60% of its rated ca p acita nce with hal f

of the rated voltage applied to it. The Z5U and Y5V also

exhibit a severe temperature effect, losing more than 50%

of nominal capacitance at high and low limits of the

temperature range.

X7R and X5R dielectric ceramic capacitors are strongly

recommended if ceramics are used, as they typically

maintain a capacitance range within 20% of nominal

over full operating ratings of temperature and voltage. Of

course, they are typically larger and more costly than Z5U/

Y5U types for a given voltage a nd capa citance.

Tantalum :

Solid tantalum capacitors are recommended for use on

the output because their typical ESR is very close to the

ideal value required for loop compensation. They also work

well as input capacitors if selected to meet the ESR

requirements previously listed.

Tantalums also have good temperature sta bility: a good

quality tantalum will typically show a capacitance value

that varies less than 10 to 15% across the full temperature

range of 125°C to −40°C. ESR will vary only about 2X

going from the high to low temperature limits.

The increasing ESR at lower temperatures can cause

oscillations when marginal quality ca pacitors are used (if

the ESR of the capacitor is near the upper limit of the

stability ra nge at room temperature).

Aluminum :

This capacitor type offers the most capacitance for the

money. The disadvantages are that they are larger in

physical size, not widely available in surfa ce mount, a nd

have poor AC performance (especially at higher

frequencies) due to higher ESR a nd ESL.

Compared by size, the ESR of an aluminum electrolytic

is higher than either Tantalum or ceramic, and it also varies

greatly with temperature. A typical aluminum electrolytic

can exhibit an ESR increase of as much as 50X when

going from 25°C down to −40°C.

It should also be noted that ma ny aluminum electrolytics

only specify impedance at a frequency of 120Hz, which

indicates they have poor high frequency performance. Only

aluminum electrolytics that have an impedance specified

at a higher frequency (between 20kHz and 100kHz) should

be used for the device. Derating must be applied to the

manufacturer's ESR specification, since it is typically

only valid at room temperature.

Any a pplication s using aluminum electrolytics should be

thoroughly tested at the lowest ambient operating

temperature where ESR is maximum.

Thermal Considerations

Thermal protection limits power dissipation in RT9183.

When the operation junction temperature exceeds 170°C,

the OTP circuit starts the thermal shutdown function a nd

turns the pass element off. The pass element turns on

again after the junction temperature cools by 30°C.

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

RT9183

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The maximum power dissipation depends on the thermal

resistance of IC package, PCB layout, the rate of

surroundings airflow and temperature difference between

junction to a mbient. 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 a mbient thermal resista nce (θJA is layout

dependent) f or SOT-223 pa ck age is 115°C/W, SOT-223

pa ckage (F-T ype) is 135°C/W, SOP-8 package is 125°C/

W, TO-252 package is 68°C/W, TO-252 package (F-Type)

is 75°C/W and TO-263 package is 45°C/W on standard

JEDEC 51-3 thermal test board.

The maximum power dissipation depends on operating

ambient temperature for fixed TJ(MAX) and thermal

resistance θJA. The Figure 4 of derating curves allows the

designer to see the effect of rising ambient temperature

on the maximum power allowed.

PCB Layout

Good board layout practices must be used or instability

can be induced because of ground loops and voltage drops.

The input and output capacitors MUST be directly

connected to the input, output, and ground pins of the

device using traces which have no other currents flowing

through them.

The best way to do this is to layout CIN and COUT near the

device with short traces to the VIN, VOUT, and ground pins.

The regulator ground pin should be connected to the

external circuit ground so that the regulator and its

capacitors have a“single point ground”..

It should be noted that stability problems have been seen

in applications where “vias” to an internal ground plane

were used at the ground points of the device and the input

and output ca pacitors. This wa s caused by varying ground

potentials at these nodes resulting from current flowing

through the ground plane. Using a single point ground

technique for the regulator and it's capacitors fixed the

problem. Since high current flows through the traces going

into VIN and coming from VOUT, Kelvin connect the capacitor

leads to these pins so there is no voltage drop in series

with the input a nd output capa citors.

Optimum performance can only be achieved when the

device is mounted on a PC board according to the diagra m

below :

SOP-8 Board Layout

GND

ADJ

GND

VIN

VOUT

EN +

Figure 4

400

800

1200

1600

2000

2400

0 25 50 75 100 125

Ambient t em perature (℃)

Maximu m power dissipation (mW)

(°C)

SOT-223

TO-263

SOP-8

SOT-223

(F-Type)

TO-252 TO-252

(F-Type)

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Adjustable Operation

The adjustable version of the RT9183 has an output voltage

range of 0.8V to 4.5V. The output voltage is set by the

ratio of two external resistors as shown in Figure 2. The

value of R2 should be less than 80k to maintain regulation.

In critical applications, small voltage drop is caused by

the resista nce (RT) of PC tra ces between the ground pin

of the device and the return pin of R2 (See Figure 5 shown

on next page). Note that the voltage drop across the

external PC trace will add to the output voltage of the

device.

Optimum regulation will be obtained at the point where

the return pin of R2 is connected to the ground pin of the

device directly .

Referring to Figure 3 the fixed voltage versions for both

SOP-8 a nd T O-263-5 pa ckage s, the ADJ pin is the input

to the error a mplifier a nd MUST be tied the ground pin of

the device directly otherwise it will be in the unstable state

if the pin voltage more than 0.1V with respect to the ground

pin itself.

Figure 5. Return Pin of External Resistor Connection

(SOP-8 & TO-263-5)

VIN VOUT

EN GND ADJ

RT9183 VOUT

VIN

Enable CIN

COUT

C10uF

0.1uF 10uF

RT9183

DS9183-21 October 2015 www.richtek.com

Outline Dimension

Symbol Dimensions In Millimeters Dimensions In Inches

Min Max Min Max

A 1.400 1.800 0.055 0.071

A1 0.020 0.100

0.001 0.004

b 0.600 0.840 0.024 0.033

B 3.300 3.700 0.130 0.146

C 6.700 7.300 0.264 0.287

D 6.300 6.700 0.248 0.264

b1 2.900 3.100 0.114 0.122

e 2.300 0.091

H 0.230 0.350 0.009 0.014

L 1.500 2.000 0.059 0.079

L1 0.800 1.100 0.031 0.043

3-Lead SOT-223 Surface Mount Package

RT9183

14 DS9183-21 October 2015www.richtek.com

8-Lead SOP Plastic Package

Dimensions In Millimeters Dimensions In In ches

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 0.170 0.254 0.007 0.010

I 0.050 0.254 0.002 0.010

J 5.791 6.200 0.228 0.244

M 0.400 1.270 0.016 0.050

RT9183

DS9183-21 October 2015 www.richtek.com

Dimensions In Millimeters Dimensions In Inches

Symbol Min Max Min Max

A 2.184 2.388 0.086 0.094

B 0.889 2.032 0.035 0.080

b 0.508 0.889 0.020 0.035

b1 1.016 Ref. 0.040 Ref.

b2 0.457 0.584 0.018 0.023

C 0.457 0.584 0.018 0.023

D 6.350 6.731 0.250 0.265

D1 5.207 5.461 0.205 0.215

E 5.334 6.223 0.210 0.245

e 2.108 2.438 0.083 0.096

L1 9.398 10.414 0.370 0.410

L2 0.508 Ref. 0.020 Ref.

L3 0.635 1.016 0.025 0.040

U 3.810 Ref. 0.150 Ref.

V 3.048 Ref. 0.120 Ref.

R 0.200 0.850 0.008 0.033

S 2.500 3.400 0.098 0.134

T 0.500 0.850 0.020 0.033

3-Lead TO-252 Surface Mount Package

RT9183

16 DS9183-21 October 2015www.richtek.com

Dimensions In Millimeters Dimensions In Inches

Symbol Min Max Min Max

A 4.064 4.826 0.160 0.190

B 1.143 1.676 0.045 0.066

b 0.660 0.914 0.026 0.036

b1 1.143 1.397 0.045 0.055

b2 0.305 0.584 0.012 0.023

C 1.143 1.397 0.045 0.055

D 9.652 10.668 0.380 0.420

E 8.128 9.652 0.320 0.380

e 2.286 2.794 0.090 0.110

L1 14.605 15.875 0.575 0.625

L2 2.286 2.794 0.090 0.110

U 6.223 Ref. 0.245 Ref.

V 7.620 Ref. 0.300 Ref.

3-Lead TO- 263 Surface Mount

RT9183

DS9183-21 October 2015 www.richtek.com

Richtek Technology Corporation

14F, No. 8, Tai Yuen 1st 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.

Dimensions In Millimeters Dimensions In Inches

Symbol Min Max Min Max

A 4.064 4.826 0.160 0.190

B 1.143 1.676 0.045 0.066

b 0.660 0.914 0.026 0.036

b2 0.305 0.584 0.012 0.023

C 1.143 1.397 0.045 0.055

D 9.652 10.668 0.380 0.420

E 8.128 9.652 0.320 0.380

e 1.524 1.829 0.060 0.072

L1 14.605 15.875 0.575 0.625

L2 2.286 2.794 0.090 0.110

U 6.223 Ref. 0.245 Ref.

V 7.620 Ref. 0.300 Ref.

5-Lead TO-263 Plastic Surface Mount Package