RT8295A Datasheet by Richtek USA Inc.

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Design

Tools Sample &

Buy

Ordering Information

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.

Pin Configurations

(TOP VIEW)

Applications

 Wireless AP/Router

Set-Top-Box

Industrial and Commercial Low Power Systems

LCD Monitors and TVs

Green Electronics/Appliances

Point of Load Regulation of High-Performance DSPs

SOP-8 (Exposed Pad)

2A, 23V, 340kHz Synchronous Step-Down Converter

General Description

The RT8295A is a high efficiency, monolithic synchronous

step-down DC/DC converter that can deliver up to 2A

output current from a 4.5V to 23V input supply. The

RT8295A's current mode architecture and external

compensation allow the transient response to be

optimized over a wide range of loads and output capacitors.

Cycle-by-cycle current limit provides protection against

shorted outputs and soft-start eliminates input current

surge during start-up. The RT8295A also provides under

voltage protection and thermal shutdown prptection. The

low current (<3μA) shutdown mode provides output

disconnection, enabling easy power management in

battery-powered systems. The RT8295A is available in a

SOP-8 (Exposed Pad) package.

Features



 ±±

±±

±1.5% High Accuracy Feedback Voltage



 4.5V to 23V Input Voltage Range



 2A Output Current



 Integrated N-MOSFET Switches



 Current Mode Control



 Fixed Frequency Operation : 340kHz



 Adjustable Output from 0.8V to 20V



 Up to 95% Efficiency



 Programmable Soft-Start



 Stable with Low-ESR Ceramic Output Capacitors



 Cycle-by-Cycle Over Current Protection



 Input Under Voltage Lockout



 Output Under Voltage Protection



 Thermal Shutdown Protection



 RoHS Compliant and Halogen Free

BOOT

VIN

GND

COMP

GND

Marking Information

RT8295AxGSP : Product Number

x : H or L

YMDNN : Date Code

RT8295AxZSP : Product Number

x : H or L

YMDNN : Date Code

RT8295Ax

GSPYMDNN

RT8295Ax

ZSPYMDNN

RT8295AxGSP RT8295AxZSP

Package Type

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

RT8295A

Lead Plating System

G : Green (Halogen Free and Pb Free)

Z : ECO (Ecological Element with

Halogen Free and Pb free)

H : UVP Hiccup

L : UVP Latch-Off

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Functional Pin Description

Pin No. Pin Name Pin Function

1 BOOT

Bootstrap for high side gate driver. Connect a 0.1F or greater ceramic

capacitor from BOOT to SW pins.

2 VIN

Input Supply Voltage, 4.5V to 23V. Must bypass with a suitably large ceramic

capacitor.

3 SW Phase Node. Connect this pin to an external L-C filter.

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

GND for maximum power dissipation.

5 FB

Feedback Input. This pin is connected to the converter output. It is used to set

the output of the converter to regulate to the desired value via an internal

resistive voltage divider. For an adjustable output, an external resistive

voltage divider is connected to this pin.

6 COMP

Compensation Node. COMP is used to compensate the regulation control

loop. Connect a series RC network from COMP to GND. In some cases, an

additional capacitor from COMP to GND is required.

7 EN

Chip Enable (Active High). A logic high enables the converter; a logic low

forces the RT8295A into shutdown mode reducing the supply current to less

than 3A. Attach this pin to VIN with a 100k pull up resistor for automatic

startup.

8 SS Soft-Start Control Input. SS controls the soft-start period. Connect a capacitor

from SS to GND to set the soft-start period. A 0.1F capacitor sets the

soft-start period to 13.5ms.

Typical Application Circuit

VOUT (V) R1 (k) R2 (k) RC (k) CC (nF) L (H) COUT (F)

8 27 3 27 3.3 22 22 x 2

5 62 11.8 20 3.3 15 22 x 2

3.3 75 24 13 3.3 10 22 x 2

2.5 25.5 12 9.1 3.3 6.8 22 x 2

1.5 10.5 12 4.7 3.3 3.6 22 x 2

1.2 12 24 3.6 3.3 3.6 22 x 2

1 3 12 3 3.3 2 22 x 2

Table 1. Recommended Component Selection

VIN

GND

BOOT

10µH

100nF

22µF x 2

75k

24k

VOUT

3.3V/2A

10µF

VIN

4.5V to 23V RT8295A

CSS

COMP

3.3nF RC

13k

Open

4, 9 (Exposed Pad)

CBOOT

CIN

0.1µF

COUT

REN 100k

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Function Block Diagram

Comparator

Oscillator

Foldback

Control

0.4V

Internal

Regulator

2.7V

Shutdown

Comparator

Current Sense

Amplifier

BOOT

VIN

GND

COMP

VA VCC

6µA

Slope Comp

Current

Comparator

-EA

0.8V

1.2V

Lockout

Comparator

VCC

130m

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Electrical Characteristics

(VIN = 12V, TA = 25°C, unless otherwise specified)

Absolute Maximum Ratings (Note 1)

Supply Voltage, VIN ------------------------------------------------------------------------------------------------ −0.3V to 25V

Input Voltage, SW -------------------------------------------------------------------------------------------------- −0.3V to (VIN + 0.3V)

VBOOT − VSW --------------------------------------------------------------------------------------------------------- −0.3V to 6V

 All Other Pin Voltages -------------------------------------------------------------------------------------------- −0.3V to 6V

Power Dissipation, PD @ TA = 25°C

SOP-8 (Exposed Pad) -------------------------------------------------------------------------------------------- 1.333W

Package Thermal Resistance (Note 2)

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

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

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

Junction Temperature ---------------------------------------------------------------------------------------------- 150°C

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

ESD Susceptibility (Note 3)

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

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

Recommended Operating Conditions (Note 4)

Supply Voltage, VIN ------------------------------------------------------------------------------------------------ 4.5V to 23V

Junction Temperature Range ------------------------------------------------------------------------------------- −40°C to 125°C

Ambient Temperature Range------------------------------------------------------------------------------------- −40°C to 85°C

Parameter Symbol Test Conditions Min Typ Max Unit

Shutdown Supply Current VEN = 0V -- 0.5 3 A

Supply Current VEN = 3 V, VFB = 0.9V -- 0.8 1.2 mA

Feedback Voltage VFB 4.5V  VIN 23V 0.788 0.8 0.812 V

Error Amplifier

Transconductance GEA IC = ± 10A -- 940 -- A/V

High Side Switch On

Resistance RDS(ON)1 -- 130 -- m

Low Side Switch

On-Resistance RDS(ON)2 -- 130 -- m

High Side Switch Leakage

Current V

EN = 0V, VSW = 0V -- 0 10 A

Upper Switch Current Limit Min. Duty Cycle, VBOOT  VSW = 4.8V -- 4.3 -- A

COMP to Current Sense

Transconductance GCS -- 4 -- A/V

Oscillation Frequency fOSC1 300 340 380 kHz

Short Circuit Oscillation

Frequency fOSC2 V

FB = 0V -- 100 -- kHz

Maximum Duty Cycle DMAX V

FB = 0.7V -- 93 -- %

Minimum On Time tON -- 100 -- ns

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Parameter Symbol Test Conditions Min Typ Max Unit

Logic-High VIH 2.7 -- 5.5

EN Input Threshold

Voltage Logic-Low VIL -- -- 0.4

Input Under Voltage Lockout Threshold VUVLO V

IN Rising 3.8 4.2 4.5 V

Input Under Voltage Lockout Hysteresis VUVLO -- 320 -- mV

Soft-Start Current ISS V

SS = 0V -- 6 -- A

Soft-Start Period tSS C

SS = 0.1F -- 13.5 -- ms

Thermal Shutdown TSD -- 150 -- C

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. θJA is measured in natural convection at TA = 25°C on a high effective thermal conductivity four-layer test board of

JEDEC 51-7 thermal measurement standard. The measurement case position of θJC is on the exposed pad of the

package.

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

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

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Reference Voltage vs. Input Voltage

0.780

0.785

0.790

0.795

0.800

0.805

0.810

0.815

0.820

4 6 8 1012141618202224

Input Voltage (V)

Reference Voltage (V)

Reference Voltage vs. Temperature

0.780

0.785

0.790

0.795

0.800

0.805

0.810

0.815

0.820

-50 -25 0 25 50 75 100 125

Temperature (C)

Reference Voltage (V)

Typical Operating Characteristics

Efficiency vs. Output Current

100

0.01 0.1 1 10

Output Current (A)

Efficiency (%)

VIN = 4.5V

VIN = 12V

VIN = 23V

VOUT = 3.3V

Switching Frequency vs. Temperature

300

310

320

330

340

350

360

370

380

-50 -25 0 25 50 75 100 125

Temperature (C)

Switching Frequency (kHz) 1

VIN = 12V, VOUT = 3.3V, IOUT = 0.5A

Switching Frequency vs. Input Voltage

300

310

320

330

340

350

360

370

380

4 6 8 1012141618202224

Input Voltage (V)

Switching Frequency (kHz) 1

VOUT = 3.3V, IOUT = 0.5A

Output Voltage vs. Output Current

3.20

3.22

3.24

3.26

3.28

3.30

3.32

3.34

3.36

3.38

3.40

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

Output Current (A)

Output Voltage (V)

VOUT = 3.3V, IOUT = 0V to 2A

VIN = 4.5V

VIN = 12V

VIN = 23V

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Output Current Limit vs. Input Voltage

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

4 6 8 1012141618202224

Input Voltage (V)

Output Current Limit (A

)

VOUT = 3.3V

Load Transient Response

Time (100μs/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 0.1A to 2A

IOUT

(1A/Div)

VOUT

(100mV/Div)

Output Voltage Ripple

Time (2.5μs/Div)

(1A/Div)

VOUT

(10mV/Div)

VSW

(10V/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 1A

Output Voltage Ripple

Time (2.5μs/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 2A

(1A/Div)

VOUT

(10mV/Div)

VSW

(10V/Div)

Load Transient Response

Time (100μs/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 1A to 2A

IOUT

(1A/Div)

VOUT

(100mV/Div)

Current Limit vs. Temperature

3.0

3.5

4.0

4.5

5.0

5.5

6.0

-50 -25 0 25 50 75 100 125

Temperature (C)

Current Limit (A)

VIN = 12V, VOUT = 3.3V

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Power On from VIN

Time (5ms/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 2A

(2A/Div)

VOUT

(2V/Div)

VIN

(5V/Div)

Power Off from VIN

Time (50ms/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 2A

(2A/Div)

VOUT

(2V/Div)

VIN

(5V/Div)

Power On from EN

Time (5ms/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 2A

VOUT

(2V/Div)

VEN

(5V/Div)

(2A/Div)

Power Off from EN

Time (5ms/Div)

VOUT

(2V/Div)

VEN

(5V/Div)

(2A/Div)

VIN = 12V, VOUT = 3.3V, IOUT = 2A

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Application Information

The RT8295A is a synchronous high voltage buck converter

that can support an input voltage range from 4.5V to 23V

while providing output current up to 2A.

Output Voltage Setting

The resistive voltage divider allows the FB pin to sense

the output voltage as shown in Figure 1.

Figure 1. Output Voltage Setting

The output voltage is set by an external resistive voltage

divider according to the following equation :









OUT FB R1

V = V1

where VFB is the feedback reference voltage (0.8V typ.).

External Bootstrap Diode

Connect a 100nF low ESR ceramic capacitor between

the BOOT pin and SW pin. This capacitor provides the

gate driver voltage for the high side MOSFET.

It is recommended to add an external bootstrap diode

between an external 5V and BOOT pin for efficiency

improvement when input voltage is lower than 5.5V or duty

ratio is higher than 65% .The bootstrap diode can be a

low cost one such as IN4148 or BAT54. The external 5V

can be a 5V fixed input from system or a 5V output of the

RT8295A. Note that the external boot voltage must be

lower than 5.5V.

Figure 2. External Bootstrap Diode

Soft-Start

The RT8295A contains an external soft-start clamp that

gradually raises the output voltage. The soft-start timing

can be programmed by the external capacitor between

SS pin and GND. The chip provides a 6μA charge current

for the external capacitor. If 0.1μF capacitor is used to

set the soft-start, the period will be 13.5ms (typ.).

Chip Enable Operation

The EN pin is the chip enable input. Pulling the EN pin

low (<0.4V) will shut down the device. During shutdown

mode, the RT8295A quiescent current drops below 3μA.

Driving the EN pin high (>2.7V, < 5.5V) will turn on the

device again. For external timing control (e.g.RC), the EN

pin can also be externally pulled high by adding a REN*

resistor and CEN* capacitor from the VIN pin

(see Figure 5).

An external MOSFET can be added to implement digital

control on the EN pin when no system voltage above 2.5V

is available, as shown in Figure 3. In this case, a 100kΩ

pull-up resistor, REN, is connected between VIN and the

EN pin. MOSFET Q1 will be under logic control to pull

down the EN pin.

Figure 3. Enable Control Circuit for Logic Control with

Low Voltage

To prevent enabling circuit when VIN is smaller than the

VOUT target value, a resistive voltage divider can be placed

between the input voltage and ground and connected to

the EN pin to adjust IC lockout threshold, as shown in

Figure 4. For example, if an 8V output voltage is regulated

from a 12V input voltage, the resistor ,REN2, can be

selected to set input lockout threshold larger than 8V.

RT8295A

GND

VOUT

BOOT

RT8295A 100nF

VIN

GND

BOOT

VOUT

Chip Enable

VIN

RT8295A

CSS COMP

CCRC

CBOOT

COUT

CIN

REN

100k

9 (Exposed Pad)

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Having a lower ripple current reduces not only the ESR

losses in the output capacitors but also the output voltage

ripple. High frequency with small ripple current can achieve

highest efficiency operation. However, it requires a large

inductor to achieve this goal.

For the ripple current selection, the value of ΔIL = 0.24 (IMAX)

will be a reasonable starting point. The largest ripple

current occurs at the highest VIN. To guarantee that the

OUT OUT

L(MAX) IN(MAX)

L = 1

fI V

 



 



 

The inductor's current rating (caused a 40°C temperature

rising from 25°C ambient) should be greater than the

maximum load current and its saturation current should

be greater than the short circuit peak current limit. Please

see Table 2 for the inductor selection reference.

Table 2. Suggested Inductors for Typical

Application Circuit

Component

Supplier Series Dimensions

(mm)

TDK VLF10045 10 x 9.7 x 4.5

TDK SLF12565 12.5 x 12.5 x 6.5

TAIYO

YUDEN NR8040 8 x 8 x 4

OUT IN

RMS OUT(MAX) IN OUT

I = I 1



This formula has a maximum at VIN = 2VOUT, where

IRMS = IOUT/2. This simple worst-case condition is

commonly used for design because even significant

deviations do not offer much relief.

Choose a capacitor rated at a higher temperature than

required. Several capacitors may also be paralleled to

meet size or height requirements in the design.

For the input capacitor, one 10μF low ESR ceramic

capacitors are recommended. For the recommended

capacitor, please refer to Table 3 for more detail.

The selection of COUT is determined by the required ESR

to minimize voltage ripple.

Moreover, the amount of bulk capacitance is also a key

for COUT selection to ensure that the control loop is stable.

Loop stability can be checked by viewing the load transient

CIN and COUT Selection

The input capacitance, CIN, is needed to filter the

trapezoidal current at the source of the high side MOSFET.

To prevent large ripple current, a low ESR input capacitor

sized for the maximum RMS current should be used. The

RMS current is given by :

OUT OUT

LIN

I = 1

fL V

 



 



 

Hiccup Mode

For the RT8295AH, Hiccup Mode Under Voltage Protection

(UVP) is provided. When the FB voltage drops below half

of the feedback reference voltage, VFB, the UVP function

will be triggered and the RT8295AH will shut down for a

period of time and then recover automatically. The Hiccup

Mode UVP can reduce input current in short circuit

conditions.

Latch-Off Mode

For the RT8295AL, Latch-Off Mode Under Voltage

Protection (UVP) is provided. When the FB voltage drops

below half of the feedback reference voltage, VFB, UVP

will be triggered and the RT8295AL will shut down in Latch-

Off Mode. In shutdown condition, the RT8295AL can be

reset via the the EN pin or power input VIN.

Inductor Selection

The inductor value and operating frequency determine the

ripple current according to a specific input and output

voltage. The ripple current ΔIL increases with higher VIN

and decreases with higher inductance.

Figure 4. The Resistors can be Selected to Set IC

Lockout Threshold.

ripple current stays below the specified maximum, the

inductor value should be chosen according to the following

equation :

VIN

GND

BOOT

VOUT

VIN

RT8295A

CSS COMP

CCRC

CBOOT

COUT

CIN

100k

12V

REN2

REN1 10µF

9 (Exposed Pad)

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OUT L OUT

VIESR

8fC



 





The output ripple will be highest at the maximum input

voltage since ΔIL increases with input voltage. Multiple

capacitors placed in parallel may be needed to meet the

ESR and RMS current handling requirement. Dry tantalum,

special polymer, aluminum electrolytic and ceramic

capacitors are all available in surface mount

packages.Special polymer capacitors offer very low ESR

value. However, it provides lower capacitance density than

other types. Although Tantalum capacitors have the highest

capacitance density, it is important to only use types that

pass the surge test for use in switching power supplies.

Aluminum electrolytic capacitors have significantly higher

ESR. However, it can be used in cost-sensitive applications

for ripple current rating and long term reliability

considerations. Ceramic capacitors have excellent low

ESR characteristics but can have a high voltage coefficient

and audible piezoelectric effects. The high Q of ceramic

capacitors with trace inductance can also lead to significant

ringing.

Higher values, lower cost ceramic capacitors are now

becoming available in smaller case sizes. Their high ripple

current, high voltage rating and low ESR make them ideal

for switching regulator applications. However, care must

be taken when these capacitors are used at input and

output. When a ceramic capacitor is used at the input

and the power is supplied by a wall adapter through long

wires, a load step at the output can induce ringing at the

response as described in a later section.

The output ripple, ΔVOUT , is determined by :

input, VIN. At best, this ringing can couple to the output

and be mistaken as loop instability. At worst, a sudden

inrush of current through the long wires can potentially

cause a voltage spike at VIN large enough to damage the

part.

Checking Transient Response

The regulator loop response can be checked by looking

at the load transient response. Switching regulators take

several cycles to respond to a step in load current. When

a load step occurs, VOUT immediately shifts by an amount

equal to ΔILOAD (ESR) and COUT also begins to be charged

or discharged to generate a feedback error signal for the

regulator to return VOUT to its steady-state value. During

this recovery time, VOUT can be monitored for overshoot or

ringing that would indicate a stability problem.

EMI Consideration

Since parasitic inductance and capacitance effects in PCB

circuitry would cause a spike voltage on SW pin when

high side MOSFET is turned-on/off, this spike voltage on

SW may impact on EMI performance in the system. In

order to enhance EMI performance, there are two methods

to suppress the spike voltage. One way is by placing an

R-C snubber between SW and GND and locating them as

close as possible to the SW pin (see Figure 5). Another

method is by adding a resistor in series with the bootstrap

capacitor, CBOOT, but this method will decrease the driving

capability to the high side MOSFET. It is strongly

recommended to reserve the R-C snubber during PCB

layout for EMI improvement. Moreover, reducing the SW

trace area and keeping the main power in a small loop will

be helpful on EMI performance. For detailed PCB layout

guide, please refer to the section Layout Considerations.

Figure 5. Reference Circuit with Snubber and Enable Timing Control

VIN

GND

BOOT

10µH

100nF

22µFx2

75k

24k

VOUT

3.3V/2A

10µF

Chip Enable

VIN

4.5V to 23V

RT8295A

CSS

0.1µF

COMP

3.3nF RC

13k

9 (Exposed Pad)

CBOOT

COUT

CIN

RBOOT*

RS*

CS*

REN*

CEN*

* : Optional

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Figure 7. Derating Curves for RT8295A Package

(a) Copper Area = (2.3 x 2.3) mm2, θJA = 75°C/W

(b) Copper Area = 10mm2, θJA = 64°C/W

Thermal Considerations

For continuous operation, do not exceed the maximum

operation junction temperature 125°C. 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 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 , TA is the ambient temperature and the θJA is

the junction to ambient thermal resistance.

For recommended operating conditions specification of

RT8295A, the maximum junction temperature is 125°C.

The junction to ambient thermal resistance θJA is layout

dependent. For SOP-8(Exposed Pad) package, the

thermal resistance θJA is 75°C/W on the standard JEDEC

51-7 four-layers thermal test board. The maximum power

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

formula :

PD(MAX) = (125°C − 25°C) / (75°C/W) = 1.333W

(min.copper area PCB layout)

PD(MAX) = (125°C − 25°C) / (49°C/W) = 2.04W

(70mm2 copper area PCB layout)

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

determined by the package architecture design and the

PCB layout design. However, the package architecture

design had been designed. If possible, it's useful to

increase thermal performance by the PCB layout copper

design. The thermal resistance θJA can be decreased by

adding copper area under the exposed pad of SOP-8

(Exposed Pad) package.

As shown in Figure 6, 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 6.a), θJA is 75°C/W.

Adding copper area of pad under the SOP-8 (Exposed

Pad) (Figure 6.b) reduces the θJA to 64°C/W. Even further

increasing the copper area of pad to 70mm2 (Figure 6.e)

reduces the θJA to 49°C/W.

The maximum power dissipation depends on operating

ambient temperature for fixed TJ(MAX) and thermal

resistance θJA. For RT8295A package, the derating curves

in Figure 7 allow the designer to see the effect of rising

ambient temperature on the maximum power dissipation .

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

0 25 50 75 100 125

Ambient Temperature (°C)

Power Dissipation (W)

Copper Area

70mm2

50mm2

30mm2

10mm2

Min.Layout

Four Layer PCB

RICHTEK HHHH DUDE RICHTEK

RT8295A

DS8295A-04 October 2016 www.richtek.com

(d) Copper Area = 50mm2 , θJA = 51°C/W (e) Copper Area = 70mm2 , θJA = 49°C/W

Figure 6. Themal Resistance vs. Copper Area Layout Design

Figure 8. PCB Layout Guide

Table 3. Suggested Capacitors for CIN and COUT

Location Component Supplier Part No. Capacitance (F) Case Size

CIN MURATA GRM31CR61E106K 10 1206

CIN TDK C3225X5R1E106K 10 1206

CIN TAIYO YUDEN TMK316BJ106ML 10 1206

COUT MURATA GRM31CR60J476M 47 1206

COUT TDK C3225X5R0J476M 47 1210

COUT MURATA GRM32ER71C226M 22 1210

COUT TDK C3225X5R1C22M 22 1210

Layout Considerations

For best performance of the RT8295A, the following layout giidelines must be strictly followed.

Input capacitor must be placed as close to the IC as possible.

SW should be connected to inductor by wide and short trace. Keep sensitive components away from this trace.

The feedback components must be connected as close to the device as possible

VIN

VOUT

GND

VOUT

COUT

Input capacitor must

be placed as close

to the IC as possible.

SW should be connected to inductor by

wide and short trace. Keep sensitive

components away from this trace.

The feedback components

must be connected as close

to the device as possible.

BOOT

VIN

GND

COMP

GND

CSS

RSCS

GND

VIN

REN

CIN

RICHTEK ’H‘ WSW @ Lmji Lguuui

RT8295A

DS8295A-04 October 2016www.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.

Outline Dimension

EXPOSED THERMAL PAD

(Bottom of Package)

8-Lead SOP (Exposed Pad) Plastic Package