®
RT9480
Easy to Use Power Bank Solution (EZPBSTM) Integrated Chip
with Two Ports Output
General Description
Features
The RT9480 is a high integration and easy to use power
solution for Li-ion power bank and other powered handheld
applications. We call it EZPBSTM (Easy to Use Power
Bank Solution). This single chip includes a linear charger,
a synchronous Boost with dual output load management
and a torch function support. The battery volume and the
state of charging and discharging can be indicated by
4LEDs. The RT9480 is available in the WQFN-24L 4x4
package.
EZPBSTM (Easy to Use Power Bank Solution)
Charger
Applications
Li-ion Power Bank
Ordering Information
One Linear Charger up to 1.2A
DPM Function (Dynamic Power Management)
Thermal Regulation
Auto-Recharge
Support JEITA Function
USB Output
RT9480
Serial Number
Package Type
QW : WQFN-24L 4x4 (W-Type)
(Exposed Pad-Option 2)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Support Dual USB Output
Auto and Button Control
Sync-Boost Total Output Current up to 2.5A
Peak Efficiency 97%
Battery State of Charge (SOC) Indicator
Note :
Richtek products are :
Compact BOM Elements with EZPBSTM Single Chip
Protection Functions (OTP, OVP, OCP, VBUS and
Output Short Protection)
Support Charging and Discharging at the same time
by Smart Algorithm
RoHS compliant and compatible with the current require-
Battery SOC Detection
Support NTC for Battery Temperature Sensing
4LEDs for Battery SOC Display
ments of IPC/JEDEC J-STD-020.
Other Functions
Suitable for use in SnPb or Pb-free soldering processes.
Torch Functions
Simplified Application Circuit
Input Power
VBUS
CIN
RT9480
VBAT
Battery
CBAT
L1
Battery
LXBST
USBOUT1
USB Port 1
USBOUT2
USB Port 2
C1
VMID
SWIN2
LEDx
LED Indicator
CVMID
TORCH
BUTTON
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
December 2014
Torch Function
GND
is a registered trademark of Richtek Technology Corporation.
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1
RT9480
Pin Configurations
Marking Information
(TOP VIEW)
VBUS
PGNDBST
PGNDBST
LXBST
LXBST
VMID
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
24 23 22 21 20 19
VBAT
TS
LED1
LED2
LED3
LED4
1
18
2
17
3
16
GND
4
15
25
5
6
14
13
8
9 10 11 12
NC
NC
GND
TORCH
BUTTON
TP1
7
USBOUT1
USBOUT1
SWIN2
USBOUT2
NC
TP2
WQFN-24L 4x4
Product Name List
Serial
Number
Product Name
Auto/Button
SOC LED
Number
Programmable
Battery
Regulation
Time Out of
USBOUT Detach
Button
4LEDs
Disable
4.2V
12 Hours
RT9480GQW
AA01
RT9480GQW-AA01
Auto
4LEDs
Disable
4.2V
3sec
AA02
RT9480GQW-AA02
Button
4LEDs
Disable
4.35V
12 Hours
AA03
RT9480GQW-AA03
Button
4LEDs
Disable
4.2V
3sec
AB01
RT9480GQW-AB01
--
--
Enable
--
--
* : Please refer to application note.
-- : Set by program
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
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2
is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
VBAT
Battery Charge Current Output.
2
TS
Battery Temperature Sense Setting.
3
LED1
Current Sink Output for LED1.
4
LED2
Current Sink Output for LED2.
5
LED3
Current Sink Output for LED3.
6
LED4
Current Sink Output for LED4.
NC
No Internal Connection.
GND
Ground. The exposed pad must be soldered to a large PCB and
connected to GND for maximum power dissipation.
10
TORCH
Current Sink Output for Torch LED Function. Open Drain Output
11
BUTTON
Button Control Input for mode change.
12
TP1
Connected to GND.
13
TP2
Connected to GND.
15
USBOUT2
USB-2 Power Output.
16
SWIN2
USB-2 Power Input.
USBOUT1
USB-1 Power Output.
VMID
Boost Output.
20, 21
LXBST
Boost Switch Output.
22, 23
PGNDBST
Boost Power GND.
VBUS
VBUS Power Supply.
7, 8, 14
9,
25 (Exposed Pad)
17, 18
19
24
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
December 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
3
RT9480
Function Block Diagram
VBUS
Linear Charger 1.2A
USBOUT1
USB-1 Load
Manager Up to 2.1A
USBOUT2
USB-2 Load
Manager Up to 1A
VBAT
TS
SWIN2
Central Control
VMID
1. Battery Capacity
Detection
2. Protection
3. LED Display
4. Mode Control
5. Button Operation
LXBST
PGNDBST
LED1
LED2
LED3
LED4
TP1
TP2
BUTTON
TORCH
Torch Brightness
Control (Open Drain)
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
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4
GND
is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
Operation
The RT9480 is a high integrated IC for Li-Ion battery power
bank. It includes a linear charger 1.2A, a synchronous
Boost 5.1V, two output load management, LED indicator
and torch function.
Change Current
Base on thermal regulation function, the charging current
can support up to 1.2A.
VBUS OVP
If the input voltage (VBUS) is higher than the threshold
voltage VOVP, the internal OVP signal will go high and the
charger will stop charging until VIN is below VOVP − ΔVOVP.
The converter has an over-temperature protection. When
the junction temperature is higher than the thermal
shutdown rising threshold, the system will be latched and
the output voltage will no longer be regulated until the
junction temperature drops under the falling threshold.
Output Short Protection
When output short to ground, the system will be latched
and the output voltage will no longer be regulated until
power reset.
CC/CV/TR Multi Loop Controller
There are constant current loop, constant voltage loop and
thermal regulation loop to control the charging current.
VMID OVP
If the internal voltage (VMID) is higher than the threshold
voltage VOVP, the internal OVP signal will go high and the
charger will stop charging until VMID is below
VOVP −ΔVOVP.
OCP
The converter senses the current signal when the highside P-MOSFET turns on. As a result, The OCP is cycle
by-cycle current limitation. If the OCP occurs, the converter
holds off the next on pulse until inductor current drops
below the OCP limit.
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
OTP
December 2014
Too Hot or Too Cold
The temperature sense input TS pin can be connected a
thermistor to determine whether the battery is too hot or
too cold for charging operation. If the battery's temperature
is out of range, charging is paused until it re-enters the
valid range.
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RT9480
Absolute Maximum Ratings
(Note 1)
Supply Voltage, VBAT -------------------------------------------------------------------------------------- −0.3V to 6V
Supply Voltage, VBUS ------------------------------------------------------------------------------------- −0.3V to 10V
Supply Voltage USBOUT1, USBOUT2 Pulse (100μs) ---------------------------------------------- −0.3V to 10V
LED Output Voltage, LED1, LED2, LED3, LED4 ---------------------------------------------------- −0.3V to 10V
TORCH --------------------------------------------------------------------------------------------------------- −0.3V to 10V
Other Pins ----------------------------------------------------------------------------------------------------- −0.3V to 6V
Power Dissipation, PD @ TA = 25°C
WQFN-24L 4x4 ---------------------------------------------------------------------------------------------- 3.57W
Package Thermal Resistance (Note 2)
WQFN-24L 4x4, θJA ----------------------------------------------------------------------------------------- 28°C/W
WQFN-24L 4x4, θJC ---------------------------------------------------------------------------------------- 7.1°C/W
Junction Temperature Range ------------------------------------------------------------------------------ 150°C
Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------- 260°C
Storage Temperature Range ------------------------------------------------------------------------------ −65°C to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Model) -------------------------------------------------------------------------------- 2kV
MM (Machine Model) --------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions
(Note 4)
Supply Input Voltage, VBAT, VBUS --------------------------------------------------------------------- 2.8V to 5.5V
Junction Temperature Range ------------------------------------------------------------------------------ −40°C to 125°C
Ambient Temperature Range ------------------------------------------------------------------------------ −40°C to 85°C
Electrical Characteristics
TOP Unit Electrical Characteristics
(VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
--
30
--
A
Supply Input
Battery Quiescent Current
IBAT_sdy
for Standby
No VBUS, Boost
on, Indicator Off.
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Button Mode
is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
Charger Unit Electrical Characteristics
(VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Supply Input
VBUS VBAT VOS Rising
VOS_H
--
100
200
mV
VBUS VBAT VOS Falling
VOS_L
10
50
--
mV
VBUS Operating Range
VBUS_CHG
4.5
--
5.5
V
VBUS Regulation
DPM
VDPM = 4.5V
5
--
5
%
VBAT Regulation
VREG
TA = 0 to 85C, VREG = 4.2V
1
--
1
%
Re-Charge Threshold
VRECHG
VREG Recharge Level
--
150
--
mV
VBUS Power FET RDS(ON)
RDS(ON)_chg IBAT = 1A
--
200
300
m
Battery Charger
Voltage Regulation
Current Regulation
Fast-Charge Current Accuracy ICHG
ICHG = 1.2A
5
--
5
%
Pre-Charge Current Accuracy
ICHG_Pre
Ratio of Fast-Charge Current
5.5
10
14.5
%
Pre-Charge Threshold
Vpre
VBAT Rising
2.35
2.5
2.65
V
Pre-Charge Threshold
Hysteresis
Vpre
VBAT Falling
120
200
280
mV
ITERMI
--
10
--
%
TF_CC
--
24
--
hour
Charge Termination Detection
Termination Current Ratio
Timer
Fast-Charge Time Fault
Boost Unit Electrical Characteristics
(VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Supply Input
Output Voltage
VOUTBST
--
5.1
--
V
Output Voltage Accuracy
VOUTBST
5
--
5
%
--
2.5
--
A
IOCP
6
--
--
A
f SW
0.2
0.25
0.3
MHz
Over-Voltage Protection
VMID_OVP
5.6
5.7
6
V
Over-Voltage Protection
Hysteresis
VMID_OVP_hys
--
0.2
--
V
Under-Voltage Protection
(Short-Circuit Protection)
VBST_FBUV
--
3.37
--
V
MAX Output Current
PFET Peak Current Limit
As VBAT > 3.3V, VOUT = 5V
Power Switch
Switching Frequency
Protection
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
December 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
7
RT9480
Others Electrical Characteristics
(VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
--
0.75
--
mA
--
200
--
mV
LED
LED Current Sink
ILED
Torch
Open-Drain Low Voltage
VODL_T
ISINK = 5mA
Button
Button Control
Press Duty
Time
Logic-High
VIH_B
1.5
--
--
V
Logic-Low
VIL_B
--
--
0.4
V
High-Level
TPress_H
0.1
--
--
sec
Low-Level
TPress_L
0.1
--
--
sec
--
105
--
°C
Protection
Charger Thermal Regulation
TREG
For Charger
Over-Temperature Protect
TOTP
--
150
--
°C
Over-Temperature Protect
Hysteresis
TOTP
--
20
--
°C
VBUS OVP Threshold Voltage
VOVP
VBUS Rising
6.5
6.8
7.1
V
VBUS OVP Threshold Voltage
Hysteresis
VOVP_Hys
VBUS Falling
--
200
280
mV
VBUS Attached Threshold
Voltage
VBUS_ATT
VBUS Rising
3.8
4
4.2
V
VBUS Attached Threshold
Voltage Hysteresis
VBUS_ATT_Hys
VBUS Falling
--
200
280
mV
BASE
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.
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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is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
Typical Application Circuit
RT9480
24
Input Power
VBUS
VBAT
1
CIN
1µF/25V
CBAT
10µF
16
19
TS
SWIN2
VMID
USBOUT1
2
17, 18
CVMID
22µF x2
COUT1
1µF
USBOUT2
L1
1µH
VBAT
C1
10µF
20, 21
22, 23
LXBST
3
D1
4
D2
LED3 5
D3
6
D4
10 R1
D6
LED1
PGNDBST
11 BUTTON
TP1
R3 100k 13
TP2
9, 25 (Exposed Pad)
LED4
TORCH
December 2014
Li-Bat
Prot-IC
N-MOSFET
USB2
Output
Power
Display
VMID
GND
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
USB1
Output
RNTC
10k
Semitec
103AT
VBAT
Button
R2 100k 12
15
COUT2
1µF
LED2
VBAT
+
-
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RT9480
Typical Operating Characteristics
USBOUT Voltage vs. Load Current
USBOUT Efficiency vs. Load Current
6.0
100
90
5.5
80
Efficiency (%)
70
Output Voltage (V)
VBAT = 3.9V
VBAT = 3.7V
VBAT = 3.3V
60
50
40
30
20
5.0
VBAT = 3.3V
VBAT = 3.7V
VBAT = 3.9V
4.5
4.0
3.5
10
USBOUT = 5.1V
USBOUT = 5.1V, L = 1μH, COUT = 1μF
3.0
0
0
500
1000
1500
2000
0
2500
500
1000
USBOUT Voltage vs. Temperature
2500
VBUS OVP Threshold Voltage vs. Temperature
5.5
7.2
OVP Threshold Voltage (V)
5.4
5.3
Output Voltage (V)
2000
Load Current (mA)
Load Current (mA)
5.2
5.1
5.0
VBAT = 3.3V
VBAT = 3.7V
VBAT = 3.9V
4.9
4.8
4.7
4.6
-50
-25
0
25
50
75
100
7.0
Rising
6.8
6.6
Falling
6.4
6.2
VBAT = Real Battery
USBOUT = 5.1V
6.0
4.5
-50
125
-25
0
Battery Regulation Voltage vs. Temperature
4.22
105°C
4.19
4.16
4.13
VIN = 5V, VBAT = Real Battery
4.10
-50
-25
0
25
50
75
100
Temperature (°C)
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10
125
50
75
100
125
ICHG Thermal Regulation vs. Temperature
ICHG Thermal Regulation (mA)
4.25
25
Temperature (°C)
Temperature (°C)
Battery Regulation Voltage (V)1
1500
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
VIN = 5V, VBAT = Real Battery
-50
-25
0
25
50
75
100
125
Temperature (°C)
is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
Application Information
The RT9480 is a high integrated IC for Li-Ion battery power
bank. This chip includes a linear charger, a synchronous
Boost, two output load management, LED indicator and
torch function.
Pre-Charge Mode
battery in order to maintain thermal regulation at around
105°C. This operation continues until the junction
temperature falls below the thermal regulation threshold
(105°C) by the hysteresis level. This feature prevents the
maximum power dissipation from exceeding typical design
conditions.
When the output voltage is lower than 2.3V, the charging
current will be reduced to a fast-charge current ratio to
protect the battery life time.
Time Fault
Fast-Charge Mode
When time fault happens, the charger cycle will be turned
off charging function.
When the output voltage is higher than 2.5V, the charging
current will be equal to the fast-charge current with 1.2A.
Constant-Voltage Mode
When the output voltage is near 4.2V or 4.35V, the charging
current will fall below the termination current.
Re-Charge Mode
When the chip is in charge termination mode, the charging
current will gradually go down to zero. However, once the
voltage of the battery drops to below 4.05V or 4.2V, then
the charging current will resume again.
Charge Termination
When the charge current is lower than the charge
termination current ratio (10%) for VBAT > 4.05V or 4.2V
and the time is larger than the deglitch time (25ms), it will
be latched high unless the power is re-toggled.
The Fast-Charge Fault Time is set by 24hours.
Battery Pack Temperature Monitoring
The RT9480 features an external battery pack temperature
monitoring input. The TS input connects to the NTC
thermistor in the battery pack to monitor battery
temperature and prevent danger over temperature
conditions. If at any time the voltage at TS falls outside of
the operating range, charging will be suspended. The NTC
thermistor recommends using 10kΩ.
JEITA Function
For JEITA battery temperature standard :
CV regulation voltage will change at the following battery
Temp ranges 45°C to 60°C.
4.35V or 4.2V
4.2V or 4.05V
Input DPM Mode
If the input voltage is lower than VDPM (4.5V), the input
current limit will be reduced to stop the input voltage from
dropping any further. This can prevent the IC from damaging
improperly configured or inadequately designed USB
sources.
Temperature Regulation
In order to maximize charge rate, the RT9480 features a
junction temperature regulation loop. If the power
dissipation of the IC results in junction temperature greater
than the thermal regulation threshold (105°C), the RT9480
will cut back on the charge current and disconnect the
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
December 2014
100% Ichg
50% Ichg
0C
10C
45C 60C
Synchronous Step-Up
The converter operates in fixed frequency PWM Mode
with 250kHz, Continuous Current Mode (CCM), and
Discontinuous Current Mode (DCM) with internal
MOSFETs.
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11
RT9480
Operation Method
Button Mode
Charge Mode : VBUS in and charging battery
Button mode : When external handheld device plug in for
power bank, the USBOUT will turns on by button.
Discharge Mode : USBOUT in and discharging for handheld
Chg-Dchg Mode : VBUS and USBOUT in, charging battery
and discharging handheld at the same time
Relax Mode : VBUS and USBOUT plug out
If device attched, RT9480 will count 12 hours
(RT9480GQW or AA02) or 3sec (AA01 or AA03) to turn
off USBOUT after detach.
AA01 and AA03. Please reference Product Name List.
Attach mean device plug in and loading > 100mA.
Detach mean device plug out and loading < 50mA.
Button Function
Function
Button
Action
Micro-USB Adapter
plug-in : ON
Charging
NA
Micro-USB Adapter
plug-out : OFF
USB slave plug-in : ON
Discharging
Check Battery
Capacity
Torch
0.1s
0.1s
After unplugging the H/H device, the power bank stops
USB slave plug-out : OFF charging the device automatically without pressing the
button.
Press the button (short
press) one time : ON
After 20sec : OFF
0.1s 0.1s
Press the button (short press), the LED battery indicator
lights up.
After 20sec, the LED battery indicator fades out.
Double click the button
(short press) : ON
Double click the button (short press), the torch light lights
up.
Double click the button
(short press : OFF
Double click the button (short press) again, the torch light
fades out.
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
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12
Description
After plugging in the external power source, the power
bank will be charged automatically without pressing the
button, and the LED battery indicator lights up at the
same time.
After unplugging the external power source, the power
bank stops being charged automatically without pressing
the button, and the LED battery indicator fades out at the
same time.
After plugging in the H/H device and pressing the button,
the power bank starts to charge the device.
is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
BUTTON Press Timing
LED Indicator Function
Define Button (Short/Long) Press Timing
About LED indicator, it will follow below table to show
SOC. The LED current is 0.75mA.
Short press = min (0.1s)
Blank = min (0.1s)
●●●●
Low→High
● : LED ON, ○ : LED OFF, ● : LED FLASH
Battery Voltage
SOC LED Flash and Running Timing
●○○○
SOC LED Flash
3700mV
0.5s
Operation of Charging
●●○○
●●●○
●●●●
0.5s
3700mV
3940mV
SOC LED Running
●●○○
●●● ○
●●● ●
0.5s
0.5s
3940mV
4100mV
●●● ●
0.5s
4100mV
4200mV
●●●●
4200mV
●●●●
Battery Voltage
Operation of Discharging
4200mV
3880mV
●●●●
3880mV
3720mV
●●●○
3720mV
3500mV
●●○○
3500mV
3200mV
3200mV
2800mV
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
●●● ○
December 2014
●○○○
●○○○
is a registered trademark of Richtek Technology Corporation.
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13
RT9480
Thermal Considerations
Layout Consideration
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 :
The PCB layout is an important step to maintain the high
performance of the RT9480.
PD(MAX) = (TJ(MAX) − TA) / θJA
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
WQFN-24L 4x4 package, the thermal resistance, θJA, is
Both the high current and the fast switching nodes demand
full attention to the PCB layout to save the robustness of
the RT9480 through the PCB layout. Improper layout might
show the symptoms of poor line or load regulation, ground
and output voltage shifts, stability issues, unsatisfying
EMI behavior or worsened efficiency.For the best
performance of the RT9480, the following PCB layout
guidelines must be strictly followed.
Place the input and output capacitors as close as
possible to the input and output pins respectively for
good filtering.
Care should be taken for a proper thermal layout. Wide
traces, connecting with vias through the layers, provides
a proper thermal path to sink the heat energy created
from the device and inductor. Keep the main power traces
as wide and short as possible. Recommend as below :
28°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 formula :
VBUS trace > 40mil;
The maximum power dissipation depends on the operating
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curve in Figure 1 allows the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
LXBST trace > 80mil;
Maximum Power Dissipation (W)1
P D(MAX) = (125°C − 25°C) / (28°C/W) = 3.57W for
WQFN-24L 4x4 package
VBAT trace > 80mil;
VMID trace > 40mil;
USBOUT1 trace > 80mil;
USBOUT2 trace > 40mil.
4.0
Four-Layer PCB
The switching node area connected to LX and inductor
should be minimized for lower EMI.
Connect the GND pin, PGNDBST pin and Exposed Pad
together to a strong ground plane for maximum thermal
dissipation and noise protection.
Directly connect the output capacitors to the feedback
network of each channel to avoid bouncing caused by
parasitic resistance and inductance from the PCB trace.
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 1. Derating Curve of Maximum Power Dissipation
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
www.richtek.com
14
is a registered trademark of Richtek Technology Corporation.
DS9480-04
December 2014
RT9480
LX should be connected to Inductor by
wide and short trace, keep sensitive
compontents away from this trace
GND
CBAT
VMID
VBAT
Input capacitors
must be placed
as close as
possible to the
Input pins.
GND
CMID
GND C1
VBUS
PGNDBST
LXBST
LXBST
VMID
24
L1
PGNDBST
VBUS
CIN
23
22
21
20
19
COUT1
VBAT 1
18 USBOUT1
TS
2
17 USBOUT1
LED1
3
LED2
4
15 USBOUT2
LED3
5
14 NC
LED4
6
13 TP2
RNTC
VBAT
D1
D2
D3
D4
16 SWIN2
GND
USBOUT1
VMID
Output
capacitors must
be placed as
close as
possible to the
Output pins.
USBOUT2
COUT2
10
11
12
TORCH
BUTTON
TP1
9
NC
NC
8
GND
R3
7
R2
R1
D6
GND
VMID
GND
Connect GND
Pin and PGND
Pin to Exposed
Pad.
Connect the Exposed Pad to a ground
plane.
Figure 2. PCB Layout Guide
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9480-04
December 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
15
RT9480
Outline Dimension
D2
D
SEE DETAIL A
L
1
E
E2
e
b
A3
Symbol
D2
E2
1
2
2
DETAIL A
Pin #1 ID and Tie Bar Mark Options
A
A1
1
Note : The configuration of the Pin #1 identifier is optional,
but must be located within the zone indicated.
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.700
0.800
0.028
0.031
A1
0.000
0.050
0.000
0.002
A3
0.175
0.250
0.007
0.010
b
0.180
0.300
0.007
0.012
D
3.950
4.050
0.156
0.159
Option 1
2.400
2.500
0.094
0.098
Option 2
2.650
2.750
0.104
0.108
E
3.950
4.050
0.156
0.159
Option 1
2.400
2.500
0.094
0.098
Option 2
2.650
2.750
0.104
0.108
e
L
0.500
0.350
0.020
0.450
0.014
0.018
W-Type 24L QFN 4x4 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.
www.richtek.com
16
DS9480-04
December 2014
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