DS7240A 00

®
RT7240A
5A, 18V, 650kHz, ACOTTM Synchronous Step-Down Converter
General Description
Features
The RT7240A is a synchronous step-down DC/DC converter
with Advanced Constant On-Time (ACOTTM) mode control.
It achieves high power density to deliver up to 5A output
current from a 4.5V to 18V input supply. The proprietary
ACOTTM mode offers an optimal transient response over a
wide range of loads and all kinds of ceramic capacitors,
which allows the device to adopt very low ESR output
capacitor for ensuring performance stabilization. In
addition, RT7240A keeps an excellent constant switching
frequency under line and load variation and the integrated
synchronous power switches with the ACOTTM mode
operation provides high efficiency in whole output current
load range. Cycle-by-cycle current limit provides an
accurate protection by a valley detection of low side
MOSFET and external soft-start setting eliminates input
current surge during startup.
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ACOTTM Mode Enables Fast Transient Response
4.5V to 18V Input Voltage Range
5A Output Current
35mΩ
Ω Internal Low Site N-MOSFET
Advanced Constant On-Time Control
Support All Ceramic Capacitors
Up to 95% Efficiency
Discontinuous Operating Mode at Light Load
Adjustable Output Voltage from 0.765V to 8V
Adjustable Soft-Start
Cycle-by-Cycle Current Limit
Input Under Voltage Lockout
Thermal Shutdown
Applications
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Ordering Information

RT7240A


Package Type
SP : SOP-8 (Exposed Pad-Option 2)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Industrial and Commercial Low Power Systems
Computer Peripherals
LCD Monitors and TVs
Green Electronics/Appliances
Point of Load Regulation for High-Performance DSPs,
FPGAs, and ASICs
Marking Information
Note :
RT7240AGSP : Product Number
RT7240A
GSPYMDNN
Richtek products are :

RoHS compliant and compatible with the current require-
YMDNN : Date Code
ments of IPC/JEDEC J-STD-020.

Suitable for use in SnPb or Pb-free soldering processes.
Simplified Application Circuit
RT7240A
VIN
VIN
SW
VOUT
BOOT
Enable
EN
VREG5
SS
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September 2014
FB
PGND
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RT7240A
Pin Configurations
(TOP VIEW)
8
EN
FB
2
VREG5
3
SS
4
PGND
VIN
7
BOOT
6
SW
5
PGND
9
SOP-8 (Exposed Pad)
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
EN
Enable Control Input. A logic-high enables the converter; a logic-low forces the IC into
shutdown mode reducing the supply current to less than 10A.
2
FB
Feedback Voltage Input. It is used to regulate the output of the converter to a set
value via an external resistive voltage divider. The feedback threshold voltage is
0.765V typically.
3
VREG5
Internal Regulator Output. Connect a 1F capacitor to GND to stabilize output
voltage.
4
SS
Soft-Start Time Setting. Connect an external capacitor between this pin and GND to set
the soft- start time.
5, 9
PGND
(Exposed Pad)
Power Ground. The exposed pad must be soldered to a large PCB and connected to
PGND for maximum power dissipation.
6
SW
Switch Node. Connect this pin to an external L-C filter.
7
BOOT
Bootstrap Supply for High Side Gate Driver. Connect a 0.1F capacitor between the
BOOT and SW pin.
8
VIN
Power Input. The input voltage range is from 4.5V to 18V. Must bypass with a suitably
large (10F x 2) ceramic capacitor.
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RT7240A
Function Block Diagram
VREG5
EN
POR &
Reg
VBIAS
BOOT
Min.
Off-Time
VREG5
OC
Control
Driver
UV & OV
SW
PGND
SW
VREG5
VIN
VREF
ZC
Ripple
Gen.
6µA
SS
VIN
FB
FB
+
Comparator
On-Time
Operation
The RT7240A is a synchronous step-down converter with
advanced constant on-time control mode. Using the
ACOTTM control mode can reduce the output capacitance
and provide fast transient response. It can minimize the
component size without additional external compensation
network.
Internal Regulator
The regulator provides 5V power to supply the internal
control circuit. Connecting a 1μF ceramic capacitor for
decoupling and stability is required.
Soft-Start
In order to prevent the converter output voltage from
overshooting during the startup period, the soft-start
function is necessary. The soft-start time is adjustable
and can be set by an external capacitor.
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September 2014
Current Protection
The inductor current is monitored via the internal switches
in cycle-by-cycle.
UVLO Protection
To protect the chip from operating at insufficient supply
voltage, the UVLO is needed. When the input voltage of
VCC is lower than the UVLO falling threshold voltage, the
device will be latch-off.
Thermal Shutdown
When the junction temperature exceeds the OTP
threshold value, the IC will shut down the switching
operation. Once the junction temperature cools down and
is lower than the OTP lower threshold, the converter will
automatically resume switching
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RT7240A
Absolute Maximum Ratings
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(Note 1)
Supply Voltage, VIN ----------------------------------------------------------------------------------------------Switch Voltage, SW ----------------------------------------------------------------------------------------------< 10ns ---------------------------------------------------------------------------------------------------------------BOOT to SW -------------------------------------------------------------------------------------------------------EN ---------------------------------------------------------------------------------------------------------------------Other Pins -----------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C
SOP-8 (Exposed Pad) -------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2)
SOP-8 (Exposed Pad), θJA --------------------------------------------------------------------------------------SOP-8 (Exposed Pad), θJC -------------------------------------------------------------------------------------Junction Temperature Range ------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) -----------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------
Recommended Operating Conditions



−0.3V to 20V
−0.8V to (VIN + 0.3V)
−5V to 25V
−0.3V to 6V
−0.3V to 20V
−0.3V to 6V
2.174W
46°C/W
7°C/W
150°C
260°C
−65°C to 150°C
(Note 3)
Supply Voltage, VIN ----------------------------------------------------------------------------------------------- 4.5V to 18V
Junction Temperature Range ------------------------------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range ------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VIN = 12V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Supply Current
Shutdown Current
ISHDN
VEN = 0V
--
1
10
A
Quiescent Current
IQ
VEN = 5V, VFB = 0.8V
--
1
1.3
mA
Logic-High
1.25
--
18
Logic-Low
--
--
0.85
Logic Threshold
EN Input Voltage
V
VFB Voltage and Discharge Resistance
TA = 25C
0.757 0.765 0.773
TA = 40C to 85C
0.755
--
0.775
--
0.01
0.1
A
4.8
5.1
5.4
V
Feedback Threshold Voltage
VFB
Feedback Input Current
IFB
VFB = 0.8V
VREG5
6V  VIN  18V, 0 < IVREG5  5mA
V
VREG5 Output
VREG5 Output Voltage
Line Regulation
6V  VIN  18V, IVREG5 = 5mA
--
--
20
mV
Load Regulation
0  IVREG5  5mA
--
--
100
mV
VIN = 6V, VREG5 = 4V, TA = 25C
--
70
--
mA
Output Current
IVREG5
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RT7240A
Parameter
Symbol
Test Conditions
Min
Typ
Max
--
120
--
--
35
--
6.2
6.8
7.5
--
150
--
--
20
--
Unit
RDS(ON)
Switch On
Resistance
High-Side
RDS(ON)_H
Low-Side
RDS(ON)_L
(VBOOT  VSW ) = 5.5V
m
Current Limit
Current Limit
ILIM
A
Thermal Shutdown
Thermal Shutdown Threshold
TSD
Shutdown Temperature
Thermal Shutdown Hysteresis TSD
C
On-Time Timer Control
On-Time
tON
VIN = 12V, VOUT = 1.05V
--
135
--
ns
Minimum Off-Time
tOFF(MIN)
VFB = 0.7V
--
260
310
ns
SS Charge Current
VSS = 0V
--
6
--
A
SS Discharge Current
VSS = 0.5V
0.1
0.2
--
mA
Wake Up VREG5
3.6
3.85
4.1
0.16
0.35
0.47
Soft-Start
UVLO
UVLO Threshold
Hysteresis
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
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 is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
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RT7240A
Typical Application Circuit
6
L1
1.4µH
7
C6
0.1µF
RT7240A
VIN
8
C1
10µF x 2
C2
0.1µF
VIN
SW
BOOT
1 EN
Input Signal
3
C4
1µF
C5
3.9nF
FB
VREG5
4 SS
PGND
VOUT
1.05V/5A
C3
C7
22µF x 2
R1
8.25k
2
5,
9 (Exposed Pade)
R2
22k
Table 1. Suggested Component Values (VIN = 12V)
V OUT (V)
R1 (k)
R2 (k)
C3 (pF)
L1 (H)
C7 (F)
1
6.81
22.1
--
1.4
22 to 68
1.05
8.25
22.1
--
1.4
22 to 68
1.2
12.7
22.1
--
1.4
22 to 68
1.8
30.1
22.1
5 to 22
2
22 to 68
2.5
49.9
22.1
5 to 22
2
22 to 68
3.3
73.2
22.1
5 to 22
2
22 to 68
5
124
22.1
5 to 22
3.3
22 to 68
7
180
22.1
5 to 22
3.3
22 to 68
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RT7240A
Typical Operating Characteristics
Efficiency vs. Output Current
100
90
90
80
80
70
70
Efficiency (%)
Efficiency (%)
Efficiency vs. Output Current
100
60
50
VIN = 5V
VIN = 12V
VIN = 18V
40
30
20
60
VIN = 5V
VIN = 12V
VIN = 18V
50
40
30
20
10
10
VOUT = 1.05V
0
0.001
0.01
0.1
1
VOUT = 1.05V
0
0.001
10
0.01
Output Current (A)
10
Feedback Threshold Voltage vs. Temperature
Output Voltage vs. Input Voltage
0.780
Feedback Threshold Voltage (V)
1.058
1.056
Output Voltage (V)
1
Output Current (A)
1.060
1.054
1.052
1.050
1.048
1.046
1.044
1.042
VIN = 4.5V to 18V, VOUT = 1.05V
0.775
0.770
0.765
0.760
0.755
VIN = 12V, VOUT = 1.05V, IOUT = 0A
0.750
1.040
4
6
8
10
12
14
16
-50
18
-25
0
Input Voltage (V)
1.09
1.09
1.08
1.08
Output Voltage (V)
1.10
1.07
1.06
1.05
VIN = 18V
VIN = 12V
VIN = 5V
1.03
50
75
100
125
Output Voltage vs. Output Current
1.10
1.04
25
Temperature (°C)
Output Voltage vs. Output Current
Output Voltage (V)
0.1
1.02
1.07
1.06
1.05
VIN = 18V
VIN = 12V
VIN = 5V
1.04
1.03
1.02
1.01
1.01
VOUT = 1.05V
1.00
VOUT = 1.05V
1.00
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Output Current (A)
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5
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Output Current (A)
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RT7240A
Switching Frequency vs. Temperature
700
690
690
Switching Frequency (kHz)1
Switching Frequency (kHz)1
Switching Frequency vs. Input Voltage
700
680
670
660
650
640
630
620
610
600
680
670
660
650
640
630
620
610
600
4
6
8
10
12
14
16
18
-50
-25
0
Input Voltage (V)
50
75
100
125
Temperature (°C)
Current Limit vs. Temperature
Current Limit vs. Input Voltage
8.0
9.0
8.5
Current Limit (A)
7.5
Current Limit (A)
25
7.0
6.5
6.0
8.0
7.5
7.0
6.5
6.0
5.5
5.5
VIN = 12V, VOUT = 1.05V
5.0
5.0
-50
-25
0
25
50
75
100
125
4
8
10
12
14
16
Input Voltage (V)
Load Transient Response
Load Transient Response
VOUT
(20mV/Div)
VOUT
(20mV/Div)
IOUT
(2A/Div)
IOUT
(2A/Div)
VIN = 12V, VOUT = 1.05V, IOUT = 0A to 5A
Time (100μs/Div)
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6
Temperature (°C)
18
VIN = 12V, VOUT = 1.05V, IOUT = 1A to 5A
Time (100μs/Div)
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RT7240A
Switching
Switching
VSW
(10V/Div)
VSW
(10V/Div)
VOUT
(5mV/Div)
VOUT
(5mV/Div)
IL
(1A/Div)
VIN = 12V, VOUT = 1.05V, IOUT = 1A
IL
(5A/Div)
Time (1μs/Div)
Time (1μs/Div)
Power On from VIN
Power Off from VIN
VIN
(10V/Div)
VIN
(10V/Div)
VOUT
(1V/Div)
VOUT
(1V/Div)
IOUT
(2A/Div)
IOUT
(2A/Div)
VIN = 12V, VOUT = 1.05V, IOUT = 5A
VIN = 12V, VOUT = 1.05V, IOUT = 5A
Time (2.5ms/Div)
Time (10ms/Div)
Power On from EN
Power Off from EN
VEN
(2V/Div)
VEN
(2V/Div)
VOUT
(1V/Div)
VOUT
(1V/Div)
IOUT
(5A/Div)
IOUT
(5A/Div)
VIN = 12V, VOUT = 1.05V, IOUT = 5A
Time (500μs/Div)
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VIN = 12V, VOUT = 1.05V, IOUT = 5A
September 2014
VIN = 12V, VOUT = 1.05V, IOUT = 5A
Time (500μs/Div)
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RT7240A
UVLO vs. Temperature
EN Threshold Voltage vs. Temperature
4.0
1.4
3.9
1.3
1.2
Rising
UVLO (V)
EN Threshold Voltage (V)
1.5
1.1
Falling
1.0
Rising
3.8
3.7
3.6
Falling
0.9
3.5
0.8
VIN = 12V, VOUT = 1.05V
0.7
3.4
-50
-25
0
25
50
75
100
Temperature (°C)
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10
125
-50
-25
0
25
50
75
100
125
Temperature (°C)
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RT7240A
Application Information
The RT7240A is a synchronous high voltage Buck converter
that can support the input voltage range from 4.5V to 18V
and the output current up to 5A. It adopts ACOTTM mode
control to provide a very fast transient response with few
external compensation components.
the EN pin can also be externally pulled high by adding a
REN resistor and CEN capacitor from the VIN pin (see Figure
1).
EN
VIN
REN
EN
PWM Operation
It is suitable for low external component count
configuration with appropriate amount of Equivalent Series
Resistance (ESR) capacitors at the output. The output
ripple valley voltage is monitored at a feedback point
voltage. The synchronous high side MOSFET is turned
on at the beginning of each cycle. After the internal
on-time expires, the MOSFET is turned off. The pulse
width of this on-time is determined by the converter's input
and output voltages to keep the frequency fairly constant
over the entire input voltage range.
GND
Figure 1. External Timing Control
An external MOSFET can be added to implement digital
control on the EN pin when no system voltage above 2V
is available, as shown in Figure 2. In this case, a 100kΩ
pull-up resistor, REN, is connected between the VIN and
EN pins. MOSFET Q1 will be under logic control to pull
down the EN pin.
Advanced Constant On-Time Control
The RT7240A has a unique circuit which sets the on-time
by monitoring the input voltage and SW signal. The circuit
ensures the switching frequency operating at 650kHz over
input voltage range and loading range.
VIN
REN
100k
The RT7240A contains an external soft-start clamp that
gradually raises the output voltage. The soft-start timing
can be programmed by the external capacitor between
the SS and GND pins. The chip provides a 6μA charge
current for the external capacitor. If a 3.9nF capacitor is
used, the soft-start will be 0.87ms (typ.). The available
capacitance range is from 2.7nF to 220nF.
C5 (nF)  1.365
ISS ( A)
RT7240A
Q1
EN
GND
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 3. 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.
VIN
REN1
EN
REN2
Chip Enable Operation
The EN pin is the chip enable input. Pulling the EN pin
low (<0.85V) will shut down the device. During shutdown
mode, the RT7240A's quiescent current drops to lower
than 10μA. Driving the EN pin high (>1.25V, <18V) will
turn on the device again. For external timing control,
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EN
Figure 2. Digital Enable Control Circuit
Soft-Start
t SS (ms) =
RT7240A
CEN
September 2014
RT7240A
GND
Figure 3. Resistor Divider for Lockout Threshold Setting
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RT7240A
Output Voltage Setting
The resistive divider allows the FB pin to sense the output
voltage as shown in Figure 4.
VOUT
R1
FB
RT7240A
R2
GND
Figure 4. Output Voltage Setting
The output voltage is set by an external resistive divider
according to the following equation. It is recommended to
use 1% tolerance or better divider resistors.
R1
VOUT = 0.765  (1
)
R2
Over Temperature Protection
The RT7240A equips an Over Temperature Protection (OTP)
circuitry to prevent overheating due to excessive power
dissipation. The OTP will shut down switching operation
when junction temperature exceeds 150°C. Once the
junction temperature cools down by approximately 20°C
the main converter will resume operation. To keep operating
at maximum, the junction temperature should be prevented
from rising above 150°C.
Inductor Selection
The inductor value and operating frequency determine the
ripple current according to a specific input and an output
voltage. The ripple current ΔIL increases with higher VIN
and decreases with higher inductance.
V
V
IL =  OUT   1 OUT 
VIN 
 f L  
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 = 0.2(IMAX) will be a reasonable
starting point. The largest ripple current occurs at the
highest VIN. To guarantee that the ripple current stays
below the specified maximum, the inductor value should
be chosen according to the following equation :
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 VOUT  
VOUT 
L =
  1  VIN(MAX) 
f
I


L(MAX)

 

Input and Output Capacitors Selection
The input capacitance, C IN, is needed to filter the
trapezoidal current at the source of the high side MOSFET.
A low ESR input capacitor with larger ripple current rating
should be used for the maximum RMS current. The RMS
current is given by :
V
IRMS = IOUT(MAX) OUT
VIN
VIN
1
VOUT
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, two 10μF and 0.1μF low ESR ceramic
capacitors are recommended.
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.
The output ripple, ΔVOUT , is determined by :
1

VOUT  IL ESR 
8fCOUT 

The output ripple will be highest at the maximum input
voltage since ΔIL increases with input voltage. Multiple
capacitors placed in parallel may need to meet the ESR
and RMS current handling requirements.
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
input, VIN. A sudden inrush of current through the long
wires can potentially cause a voltage spike at VIN large
enough to damage the part.
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September 2014
RT7240A
External Bootstrap Diode
Thermal Considerations
Connect a 0.1μF low ESR ceramic capacitor between the
BOOT and SW pins. 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 the 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 1N4148
or BAT54. The external 5V can be a 5V fixed input from
system or a 5V output of the RT7240A. Note that the
external boot voltage must be lower than 5.5V
For continuous operation, do not exceed absolute
maximum junction temperature. The maximum power
dissipation depends on the thermal resistance of the IC
package, PCB layout, rate of surrounding airflow, and
difference between junction and ambient temperature. The
maximum power dissipation can be calculated by the
following formula :
BOOT
RT7240A
0.1µF
SW
Figure 5. External Bootstrap Diode
PVCC Capacitor Selection
Decouple with a 1μF ceramic capacitor. X7R or X5R grade
dielectric ceramic capacitors are recommended for their
stable temperature characteristics.
Over Current Protection
When the output shorts to ground, the inductor current
decays very slowly during a single switching cycle. An
over current detector is used to monitor inductor current
to prevent current runaway. The over current detector
monitors the voltage between SW and GND during the
low side MOS turn-on state. This is cycle-by-cycle
protection.
where TJ(MAX) is the maximum junction temperature, TA is
the ambient temperature, and θJA is the junction to ambient
thermal resistance.
For recommended operating condition specifications, 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 46°C/W on a standard JEDEC 51-7 four-layer
thermal test board. The maximum power dissipation at
TA = 25°C can be calculated by the following formulas :
PD(MAX) = (125°C − 25°C) / (46°C/W) = 2.174W for
SOP-8 (Exposed Pad) package
The maximum power dissipation depends on operating
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curves in Figure 6 allow the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
3.2
Maximum Power Dissipation (W)1
5V
PD(MAX) = (TJ(MAX) − TA) / θJA
Four-Layer PCB
2.8
2.4
2.0
1.6
1.2
0.8
0.4
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 6. Derating Curve of Maximum Power Dissipation
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS7240A-00
September 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT7240A
Layout Consideration
Follow the PCB layout guidelines for optimal performance
of the RT7240A

Keep the traces of the main current paths as short and
wide as possible.

Put the input capacitor as close as possible to the device
pins (VIN and PGND).

SW node is with high frequency voltage swing and
should be kept at small area. Keep sensitive
components away from the SW node to prevent stray
capacitive noise pickup.

Connect feedback network behind the output capacitors.
Keep the loop area small. Place the feedback
components near the RT7240A FB pin.
The resistor divider must
be connected as close to
the device as possible.
VOUT
R1
R2
PGND
C4
C5
C1
C2
8
EN
FB
2
VREG5
3
SS
4
7
PGND
6
9
5
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
VIN components away from this trace.
BOOT
C6
SW
L1
PGND
C7
VOUT
Figure 7. PCB Layout Guide
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
www.richtek.com
14
is a registered trademark of Richtek Technology Corporation.
DS7240A-00
September 2014
RT7240A
Outline Dimension
H
A
M
EXPOSED THERMAL PAD
(Bottom of Package)
Y
J
X
B
F
C
I
D
Dimensions In Millimeters
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
Y
2.000
2.300
0.079
0.091
X
2.100
2.500
0.083
0.098
Y
3.000
3.500
0.118
0.138
Option 1
Option 2
8-Lead SOP (Exposed Pad) Plastic Package
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.
DS7240A-00
September 2014
www.richtek.com
15