Anpec APW7323 3.2a, 5v, 1mhz synchronous buck converter Datasheet

APW7323/A
3.2A, 5V, 1MHz Synchronous Buck Converter
Features
General Description
•
High Efficiency up to 94%
APW7323/A is a synchronous buck converters with inte-
•
Adjustable Output Voltage from 0.8V to VPVDD
•
Operating from 2.9 to 6V Supply
grated 85mΩ high side and 75mΩ low side power
MOSFETs. The APW7323/A with a current-mode control
•
Integrated 85mΩ High Side / 75mΩ Low Side
scheme can convert wide input voltage of 2.9V to 6V to
the output voltage adjustable from 0.8V to 6V to provide
MOSFETs
•
Low Dropout Operation: 100% Duty Cycle
•
Stable with Low ESR Ceramic Capacitors
•
Current up to 3.2A
•
Power-On-Reset Detection on VCC and VIN
•
Model Selection :
excellent output voltage regulation.
The APW7323/A is equipped with an automatic Skip/PWM
mode operation. At light load , the IC operates in the Skip
mode to reduce the switching losses. At heavy load, the
IC works in PWM mode.
The APW7323/A is also equipped with Power-on-reset,
soft start, soft-stop, and whole protections (under-voltage,
over-voltage, over-temperature and current-limit) into a
APW7323 : Automatic PFM/PWM
APW7323A : Forced PWM
•
Integrate Soft-Start and Soft-Stop
•
Over-Temperature Protection
•
Over-Voltage Protection
•
Under-Voltage Protection
•
High/ Low Side Current Limit
•
Power Good Indication
•
Enable/Shutdown Function
•
Available in SOP-8P and TDFN3x3-10 Package
•
Lead Free and Green Devices Available
single package.
This device, available in SOP-8P and TDFN3x3-10
packages, provides a very compact system solution external components and PCB area.
Simplified Application Circuit
VIN
(RoHS Compliant)
VIN
C2
VCC
Applications
Notebook Computer & UMPC
•
Set-Top Box
•
DSL, Switch HUBr
•
Portable Instrument
L1
OFF
LCD Monitor/TV
FB
EN
VOUT
LX
C3 APW7323/A
ON
•
•
R3
POK
GND PGND
R1
C4
R2 C1
(optional)
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and
advise customers to obtain the latest version of relevant information to verify before placing orders.
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
1
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APW7323/A
Pin Configuration
VCC 1
8
7
6
5
POK 2
GND 3
FB 4
EN
PGND
PGND
LX
LX
VIN
LX
PGND
EN
1
2
3
4
5
SOP-8P
(Top View)
10
9
8
7
6
EP
FB
GND
POK
VCC
VIN
TDFN3x3-10
(Top View)
Exposed Pad
(connected to GND plane for better heat dissipation
EP
Exposed Pad
(connected to GND plane for better heat dissipation)
Ordering and Marking Information
Package Code
KA: SOP-8P
APW7323
APW7323A
Assembly Material
QB : TDFN3x3-10
Operating Ambient Temperature Range
I : -40 to 85 oC
Handling Code
Handling Code
TR : Tape & Reel
Temperature Range
Package Code
Assembly Material
G : Halogen and Lead Free Device
APW7323 KA:
APW7323A KA:
APW7323
XXXXX
APW7323A
XXXXX
XXXXX - Date Code
APW7323 QB:
XXXXX - Date Code
APW7323A QB:
APW
7 323
XXXXX
XXXXX - Date Code
APW
732 3A
XXXXX
XXXXX - Date Code
Note: ANPEC lead-free products contain molding compounds/die attach materials and 100% matte tin plate termination finish; which
are fully compliant with RoHS. ANPEC lead-free products meet or exceed the lead-free requirements of IPC/JEDEC J-STD-020D for
MSL classification at lead-free peak reflow temperature. ANPEC defines “Green” to mean lead-free (RoHS compliant) and halogen
free (Br or Cl does not exceed 900ppm by weight in homogeneous material and total of Br and Cl does not exceed 1500ppm by
weight).
Absolute Maximum Ratings (Note 1)
Symbol
VIN, VCC
Parameter
VIN and VCC Input Voltage
>20ns
VLX
LX to GND Voltage
<20ns
FB, EN, POK to GND Voltage
PD
Power Dissipation
TJ
Junction Temperature
TSTG
TSDR
Rating
Unit
-0.3 ~ 7
V
-1 ~VIN+0.3
-0.3 ~ 6.5
Internally Limited
Storage Temperature
Maximum Lead Soldering Temperature(10 Seconds)
V
VPGND -5V ~9V
V
W
150
o
-65 ~ 150
o
260
o
C
C
C
Note1: Stresses beyond those listed under "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 under "recommended operating conditions" is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device
reliability
Copyright  ANPEC Electronics Corp.
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APW7323/A
Thermal Characteristics
Symbol
Parameter
Typical Value
Unit
Junction-to-Ambient Resistance in Free Air (Note 2)
θJA
SOP-8P
TDFN3x3-10
50
SOP-8P
TDFN3x3-10
12
6
o
C/W
Junction-to-Case Resistance in Free Air (Note 3)
θJC
o
C/W
Note 2: θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. The exposed pad
of SOP-8P and TDFN3x3-10 is soldered directly on the PCB.
Note 3: The case temperature is measured at the center of the exposed pad on the underside of the package.
Recommended Operating Conditions (Note 4)
Symbol
VCC
VIN
VOUT
L
Parameter
Range
Unit
VCC Supply Voltage
2.9~ 6
V
VIN Supply Voltage
2.6~6
V
Converter Output Voltage
0.8~6
V
Inductance
1~4.7
µH
10~220
µF
COUT
Output Capacitor
IOUT
Converter Output Current
TA
TJ
0~3.2
Ambient Temperature
Junction Temperature
A
-40 ~ 85
o
-40 ~ 125
o
C
C
Note 4: Refer to the typical application circuit.
Electrical Characteristics
Unless otherwise specified, these specifications apply over VCC=VIN=5V, VOUT=3.3V and TA=-40~85oC. Typical values
are at TA=25oC.
Symbol
Parameter
APW7323/A
Test Conditions
Min.
Typ.
Unit
Max.
SUPPLY CURRENT
IVCC
IVCC_SD
VCC Supply Current
VFB=0.7V
-
460
-
µA
VCC Shutdown Supply Current
EN=GND
-
-
40
µA
VCC POR Voltage Threshold
VCC Rising
-
2.7
-
V
VCC POR Voltage Hysteresis
VCC Falling
-
200
-
mV
µs
POWER-ON-RESET (POR)
VCC Debounce Time
-
10
-
VIN POR Voltage Threshold
VIN Rising
-
2.3
-
V
VIN POR Voltage Hysteresis
VIN Falling
-
50
-
mV
-
0.8
-
V
All temperature
-1
-
+1
%
-1.5
-
+1.5
%
REFERENCE VOLTAGE
VREF
Reference Voltage
Output Accuracy
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
IOUT=10mA~3A, VCC=2.9~5V
3
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APW7323/A
Electrical Characteristics (Cont.)
Unless otherwise specified, these specifications apply over VCC=VIN=5V, VOUT=3.3V and TA=-40~85oC. Typical values
are at TA=25oC.
Symbol
Parameter
APW7323/A
Test Conditions
Min.
Typ.
Unit
Max.
OSCILLATOR and DUTY CYCLE
FOSC
Oscillator Frequency
0.85
1
1.15
-
100
-
%
-
70
-
ns
-
85
115
mΩ
-
75
105
mΩ
-
680
-
µA/V
-
50
-
dB
Current Sense Resistance
-
400
-
mΩ
Dead Time
-
20
-
ns
4.2
5.4
6.6
A
-
160
-
°C
-
50
-
°C
120
125
130
%VREF
-
3
-
µs
45
50
55
%VREF
-
3
-
µs
-
-1.9
-
A
-
2.5
-
ms
Maximum Converter’s Duty
VFB=0.7V
Minimum on Time
MHz
POWER MOSFET
High Side P-MOSFET Resistance
Low Side N-MOSFET Resistance
VCC=VIN=5V, ILX=0.5A, TA=25oC
o
VCC=VIN=5V, ILX=0.5A, TA=25 C
CURRENT -MODE PWM CONVERTER
Gm
Error Amplifier Transconductance
Error Amplifier DC Gain
TD
COMP=NC
PROTECTIONS
ILIM
TOTP
High Side MOSFET Current-Limit
Peak Current
Over-temperature Trip Point
(Re-softstart after OTP)
Over-Temperature Hysteresis
Over- Voltage Protection Threshold
OVP Debounce Time
Under-Voltage Protection Threshold
UVP Debounce Time
Low Side Switch Current-Limit
From Drain to Source
SOFT-START, ENABLE and INPUT CURRENTS
Soft Start time
EN Enable Threshold Voltage
0.8
-
1.3
V
EN Threshold Hysteresis
VEN Rising
-
0.2
-
V
EN Pull High Resistance
-
300
-
KΩ
POK in from lower
(POK goes high)
85
87.5
90
%VOUT
POK low hysteresis
-
5
-
%VOUT
POK in from higher
(POK goes high)
110
112.5
115
%VOUT
POK high hysteresis
-
5
-
%VOUT
POWER GOOD
POK Threshold
POK Pull Low Resistance
-
1
-
kΩ
POK Low-to-High Debounce Time
-
0.5
-
ms
Copyright  ANPEC Electronics Corp.
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APW7323/A
Pin Description
Pin
Function
NO.
Name
SOP-8P
TDFN3x3-10
1
7
VCC
2
8
POK
3
9
GND
4
10
FB
Output Feedback Input. The APW7323/A senses the feedback voltage via FB and
regulates the voltage at 0.8V. Connecting FB with a resistor-divider from the converter’s
output sets the output voltage.
5
1
EN
Enable Input. EN is a digital input that turns the regulator on or off. Driving the EN high
turns on the regulator, otherwise, driving it low turns it off. The EN pin is internally pulled
high via a 300kΩ resistor.
6
2,3
7
4,5
LX
Power Switching Output. LX is the Junction of the high-side and low-side Power MOSFETs
to supply power to the output LC filter.
8
6
VIN
Power Input. VIN supplies the step-down converter switches.
9
11
Signal Input. VCC supplies the control circuitry, gate drivers. Connecting a ceramic bypass
capacitor from VCC to GND to eliminate switching noise and voltage ripple on the input to
the IC.
Power Good Output. This pin is open-drain logic output that is
pulled to ground when the output voltage is not within ±12.5% of regulation point. The POK
pin, if used, needs an external pull high resistor in the range of 30kΩ~100kΩ.
Ground. Power and signal ground.
PGND Power Ground.
Exposed Exposed pad. Connect the exposed pad to the system ground plan with large copper area
Pad
for dissipating heat into the ambient air.
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
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APW7323/A
Typical Operating Characteristics
Efficiency vs. Output Current
Efficiency vs. Output Current
100
100
90
VOUT =3.3V
90
VOUT =3.3V
80
Efficiency(%)
Efficiency(%)
70
80
VOUT =1.8V
70
VOUT =1.2V
VOUT =1.2V
60
50
VOUT =1.8V
40
30
60
20
APW7323, VIN =5V
10
50
APW7323A, VIN =5V
0
0.001
0.01
0.1
10
1
0
0.01
Output Current, IOUT(A)
10
On-Resistance vs. VIN Voltage
4.5
120
4.0
115
On- Resistance, RDS(ON) (mΩ)
High Side MOSFET Current Limit
Threshold, ILIM (A)
1
Output Current, IOUT(A)
High Side MOSFET Current Limit
Threshold vs. VIN Voltage
3.5
3.0
2.5
2.0
1.5
1.0
0.5
TA=25℃
110
P-MOSFET
105
N-MOSFET
100
95
90
85
80
75
70
0.0
2.5
3
3.5
4.5
4
5
5.5
2.5
6
3
3.5
4
4.5
5
5.5
VIN Voltage,VVIN(V)
VIN Voltage, VVIN (V)
Reference Voltage vs. Output
Current
VCC Supply Current vs. VCC
Supply Voltage
6
600
0.85
VCC Supply Current, IVCC (µA)
0.84
Reference Voltage, VREF (V)
0.1
0.83
0.82
0.81
0.80
0.79
0.78
0.77
500
400
300
200
100
0.76
0
0.75
0
0.5
1
1.5
2.5
2
Output Current, IOUT(A)
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
VCC =5V, VIN =5V, VOUT =3.3V,
No Load, TA=25℃
3
3 .5
4
4.5
5
5 .5
6
VCC Supply Voltage (V)
6
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APW7323/A
Operating Waveforms
The test condition is APW7323, VIN=VCC=5V, VOUT=1.8V, COUT =22µFx2, L=2.2µH, TA= 25oC unless otherwise specified.
Shutdown without Loading
Enable without Loading
VEN
VEN
1
1
VOUT
VOUT
2
2
V POK
VPOK
3
3
IL
IL
4
4
No load , Enable Power On
No load, Enable Power On
CH1: VEN, 5V/Div, DC
CH2: VOUT, 1V/Div, DC
CH3: VPOK, 5V/Div, DC
CH4: IL, 1A/Div, DC
TIME: 1ms/Div
CH1: VEN, 5V/Div, DC
CH2: VOUT, 1V/Div, DC
CH3: VPOK, 5V/Div, DC
CH4: IL, 1A/Div, DC
TIME: 200µs/Div
Enable with 1A Loading
Shutdown with 1A Loading
VEN
VEN
1
1
VOUT
VOUT
2
2
V POK
3
VPOK
3
IL
4
IL
4
IOUT=1A, Enable Power On
IOUT=1A, Enable Power On
CH1: VEN, 5V/Div, DC
CH2: VOUT, 1V/Div, DC
CH3: VPOK, 5V/Div, DC
CH4: IL, 1A/Div, DC
TIME: 1ms/Div
CH1: VEN, 5V/Div, DC
CH2: VOUT, 1V/Div, DC
CH3: VPOK, 5V/Div, DC
CH4: IL, 1A/Div, DC
TIME: 100µs/Div
Copyright  ANPEC Electronics Corp.
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APW7323/A
Operating Waveforms
The test condition is APW7323, VIN=VCC=5V, VOUT=1.8V, COUT =22µFx2, L=2.2µH, TA= 25oC unless otherwise specified.
Load Transient
Load Transient
VOUT
VOUT
1
1
IOUT
I OUT
2
2
IOUT=100mA-3A-100mA, Slew Rate=1A/µs
IOUT=1A-3A-1A, Slew Rate=1A/µs
CH1: VOUT, 100mV/Div, offset=1.8V
CH2: IOUT, 1A/Div, DC
CH1: VOUT, 100mV/Div, offset=1.8V
TIME: 50µs/Div
TIME: 20µs/Div
CH2: IOUT, 1A/Div, DC
Current Limit
Over Voltage Protection
V OUT
VOUT
1
VPOK
VPOK
1
2
2
I OUT
IL
3
3
IOUT=100mA, a 2.5V power source is externally
attached to VOUT
CH1: VOUT, 1V/Div, DC
CH2: VPOK, 5V/Div, DC
CH3: IL, 2A/Div, DC
TIME: 200µs/Div
CH1: VOUT ,1V/Div, DC
CH2: VPOK, 5V/Div, DC
CH3: IOUT, 2A/Div, DC
TIME: 200µs/Div
Copyright  ANPEC Electronics Corp.
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APW7323/A
Operating Waveforms
The test condition is APW7323, VIN=VCC=5V, VOUT=1.8V, COUT =22µFx2, L=2.2µH, TA= 25oC unless otherwise specified.
Normal Operation in Heavy Load
Normal Operation in Ligh Load
VOUT
V OUT
1
1
VLX
VLX
2
2
IL
IL
3
3
IOUT=200mA
IOUT=3A
CH1: VOUT, 50mV/Div, offset=1.8V
CH2: VLX, 5V/Div, DC
CH3: ILX, 1A/Div, DC
TIME: 2µs/Div
CH1: VOUT, 50mV/Div, offset=1.8V
CH2: VLX, 5V/Div, DC
CH3: ILX, 2A/Div, DC
TIME: 0.5µs/Div
Copyright  ANPEC Electronics Corp.
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APW7323/A
Block Diagram
VIN
VCC
Current Sense
Amplifier
LOC
Over
Temperature
Protection
Power -OnReset
Current
Limit
Zero Crossing
Comparator
POR
OTP
125 %V REF
OVP
Fault
Logics
50%V REF
UVP
Inhibit
Gate
Control
112.5%VREF
LX
Gate
87.5%VREF
Error
Amplifier
FB
Current
Comparator
Driver
Gat
e
Gm
Soft start
V REF
0.8V
Slope
Compensation
LOC
Current Sense
Amplifier
Oscillator
Shutdown
PGND
300kΩ
VCC
EN
POK
Copyright  ANPEC Electronics Corp.
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GND
10
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APW7323/A
Typical Application Circuit
VIN
5V
VOUT
1.8V/3.2A
VIN
LX
R4
2.2Ω
CIN
22µF
VCC
100kΩ
FB
C2
1µF
Off
R5
C3
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
C1
22pF
R1
25kΩ
COUT
22 µ Fx2
APW7323/A
R2
20kΩ
POK
On
L1
2.2 µH
EN
GND
PGND
Exposed
pad
11
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APW7323/A
Function Description
VCC and VIN Power-On-Reset (POR)
The thermal sensor allows the converters to start a start-
TThe APW7323/A keeps monitoring the voltage on VIN
and VCC pins to prevent wrong logic operations which
up process and to regulate the output voltage again after
the junction temperature cools by 50oC. The OTP is de-
may occur when VIN or VCC voltage is not high enough
for internal control circuitry to operate. The VCC POR ris-
signed with a 50 oC hysteresis to lower the average TJ
during continuous thermal overload conditions, increas-
ing threshold is 2.7V (typical) with 0.2V hysteresis and
VIN POR rising threshold is 2.3V with 0.05V hysteresis.
ing lifetime of the APW7323/A.
Current-Limit Protection
During startup, the VCC and VIN voltage must exceed the
POR threshold. Then the IC starts a starts-up process
The APW7323 monitors the output current, flows through
the high-side and low-side power MOSFETs, and limits
the current peak at current-limit level to prevent the IC
and ramps up the output voltage to the voltage target.
from damaging during overload, short-circuit and overvoltage conditions. Typical high side power MOSFET cur-
Output Under-Voltage Protection (UVP)
In the operational process, if a short-circuit occurs, the
rent limit is 4.8A, and low side MOSFET current limit is 1.
9A.
output voltage will drop quickly. Before the current-limit
circuit responds, the output voltage will fall out of the re-
Soft-Start
quired regulation range. The under-voltage continually
monitors the FB voltage after soft-start is completed. If a
The APW7323/A has a built-in soft-start to control the rise
rate of the output voltage and limit the input current surge
during start-up. During soft-start, an internal voltage ramp
load step is strong enough to pull the output voltage lower
than the under-voltage threshold, the IC shuts down
connected to one of the positive inputs of the error
converter’s output.
amplifier, rises up from 0V to 0.95V to replace the reference voltage (0.8V) until the voltage ramp reaches the
The under-voltage threshold is 50% of the nominal output voltage. The under-voltage comparator has a built-in
reference voltage. During soft-start without output overvoltage, the APW7323/A converter’s sinking capability is
3µs noise filter to prevent the chips from wrong UVP shutdown being caused by noise. The APW7323/A will be
disabled until the output voltage reaches the voltage target.
latched after under-voltage protection.
Soft-Stop
Over-Voltage Protection (OVP)
At the moment of shutdown controlled by EN signal, un-
The over-voltage function monitors the output voltage by
der-voltage event or over-temperature protection, the
APW7323/A initiates a soft-stop process to discharge the
FB pin. When the FB voltage increases over 125% of the
reference voltage due to the high-side MOSFET failure or
output voltage in the output capacitors. Certainly, the load
current also discharges the output voltage. During soft-
for other reasons, the over-voltage protection comparator
will force the low-side MOSFET gate driver high. This ac-
stop, the internal voltage ramp (VRAMP) falls down from 0.
95V to 0V to replace the reference voltage. Therefore, the
tion actively pulls down the output voltage and eventually
attempts to blow the internal bonding wires. As soon as
output voltage falls down slowly at the light load. After the
soft-stop interval elapses, the soft-stop process ends and
the output voltage is less than 0.2V, the APW7323/A will
be latched off and needs a POR or enable to recover to
the IC turns on the low-side power MOSFET.
normal operation.
Enable and Shutdown
Over-Temperature Protection (OTP)
Driving EN to ground places the APW7323/A in shutdown.
The over-temperature circuit limits the junction tempera-
In shutdown mode, the internal power MOSFETs turns
off, all internal circuitry shuts down and the quiescent
ture of the APW7323/A. When the junction temperature
exceeds TJ =160oC, a thermal sensor turns off the both
supply current reduces to less than 20µA.
power MOSFETs, allowing the devices to cool.
Copyright  ANPEC Electronics Corp.
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APW7323/A
Function Description (Cont.)
Power Good Indicator
POK is actively held low in shutdown and soft-start status.
In the soft-start process, the POK is an open-drain. When
the soft-start is finished, the POK is released. In normal
operation, the POK window is from 87.5% to 112.5% of
the converter reference voltage. When the output voltage
has to stay within this window, POK signal will become
high after 0.5ms internal delay. When the output voltage
outruns 82.5% or 117.5% of the target voltage, POK signal will be pulled low immediately. In order to prevent
false POK drop, capacitors need to parallel at the output
to confine the voltage deviation with severe load step
transient. The POK pin, if used, needs an axternal pull
high resistor, the recommended resistor should be in
the range of 30KΩ to 100KΩ.
Copyright  ANPEC Electronics Corp.
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APW7323/A
Application Information
Input Capacitor Selection
shown in “Typical Application Circuits”. A suggestion of
Because buck converters have a pulsating input current,
maximum value of R2 is 300kΩ to keep the minimum
current that provides enough noise rejection ability through
a low ESR input capacitor is required. This results in the
best input voltage filtering, minimizing the interference
the resistor divider. The output voltage can be calculated
as below:
with other circuits caused by high input voltage spikes.
Also, the input capacitor must be sufficiently large to sta-
R1 

VOUT = VREF ⋅  1 +

R2 

bilize the input voltage during heavy load transients. For
good input voltage filtering, usually a 22µF input capaci-
VOUT
tor is sufficient. It can be increased without any limit for
better input voltage filtering. Ceramic capacitors show
R1≤1MΩ
better performance because of the low ESR value, and
they are less sensitive against voltage transients and
FB
R2 ≤ 300KΩ
APW7323
spikes compared to tantalum capacitors. Place the input
capacitor as close as possible to the input and GND pin
GND
of the device for better performance.
Output Capacitor Selection
Inductor Selection
For high efficiencies, the inductor should have a low dc
The current-mode control scheme of the APW7323 allows the use of tiny ceramic capacitors. The higher ca-
resistance to minimize conduction losses. Especially at
high-switching frequencies the core material has a higher
pacitor value provides the good load transients response.
Ceramic capacitors with low ESR values have the lowest
impact on efficiency. When using small chip inductors,
output voltage ripple and are recommended. If required,
tantalum capacitors may be used as well. The output
the efficiency is reduced mainly due to higher inductor
core losses. This needs to be considered when select-
ripple is the sum of the voltages across the ESR and the
ideal output capacitor.
ing the appropriate inductor. The inductor value determines the inductor ripple current. The larger the inductor
value, the smaller the inductor ripple current and the lower
the conduction losses of the converter. Conversely, larger
∆VOUT
inductor values cause a slower load transient response.
A reasonable starting point for setting ripple current, ∆IL,


 
1
 ⋅  ESR +

8 ⋅ FSW ⋅ COUT





When choosing the input and output ceramic capacitors,
choose the X5R or X7R dielectric formulations. These
is 40% of maximum output current. The recommended
inductor value can be calculated as below:

V
VOUT 1 − OUT
VIN

L≥
FSW ⋅ ∆IL

V
VOUT ⋅ 1 − OUT
VIN

≅
FSW ⋅ L
dielectrics have the best temperature and voltage characteristics of all the ceramics for a given value and size.




VIN
IIN
IP-FET
IL(MAX) = IOUT(MAX) + 1/2 x ∆IL
IL
To avoid saturation of the inductor, the inductor should be
rated at least for the maximum output current of the con-
CIN
verter plus the inductor ripple current.
P-FET
VOUT
LX
N-FET
Output Voltage Setting
IOUT
ESR
COUT
In the adjustable version, the output voltage is set by a
resistive divider. The external resistive divider is connected to the output, allowing remote voltage sensing as
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
14
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APW7323/A
Application Information (Cont.)
Recommended Minimum Footprint
Output Capacitor Selection (Cont.)
IL
ILIM
8
7
6
5
3
4
IPEAK
1.3
0.5
∆IL
3.8
2.3
6.0
IOUT
IP-FET
1
2
1.27
Unit : mm
SOP-8P
Layout Considerations
For all switching power supplies, the layout is an important step in the design; especially at high peak currents
ThermalVia diameter
12mil X 5
Ground plane for
ThermalPAD
0.75mm
0.275mm
0.30mm
and switching frequencies. If the layout is not carefully
done, the regulator might show noise problems and duty
2.70mm
cycle jitter.
1. The input capacitor should be placed close to the VIN
and GND. Connect the capacitor and VIN/GND with short
and wide trace without any via holes for good input volt0.50mm
age filtering. The distance between VIN/GND to capacitor
less than 2mm respectively is recommended.
1.75mm
2. To minimize copper trace connections that can inject
noise into the system, the inductor should be placed as
TDFN3X3 -10
close as possible to the LX pin to minimize the noise
coupling into other circuits.
3. The output capacitor should be place closed to VOUT
and GND.
4. Keep the sensitive small signal nodes (FB) away from
switching nodes (LX) on the PCB. Therefore place the
feedback divider and the feedback compensation network close to the IC to avoid switching noise. Connect
the ground of feedback divider directly to the GND pin of
the IC using a dedicated ground trace.
5. A star ground connection or ground plane minimizes
ground shifts and noise is recommended.
Copyright  ANPEC Electronics Corp.
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APW7323/A
Package Information
SOP-8P
D
SEE VIEW A
h X 45o
E
THERMAL
PAD
E1
E2
D1
c
A1
0.25
A2
A
b
e
GAUGE PLANE
SEATING PLANE
θ
L
VIEW A
S
Y
M
B
O
L
SOP-8P
INCHES
MILLIMETERS
MAX.
MIN.
A
MIN.
MAX.
1.60
A1
0.00
A2
1.25
b
0.31
0.063
0.000
0.15
0.006
0.049
0.51
0.012
0.020
0.010
c
0.17
0.25
0.007
D
4.80
5.00
0.189
0.197
D1
2.50
3.50
0.098
0.138
0.244
E
5.80
6.20
0.228
E1
3.80
4.00
0.150
0.157
E2
2.00
3.00
0.079
0.118
e
1.27 BSC
0.050 BSC
h
0.25
0.50
0.010
0.020
L
0.40
1.27
0.016
0.050
0o C
8o C
0
0oC
8oC
Note : 1. Followed from JEDEC MS-012 BA.
2. Dimension "D" does not include mold flash, protrusions or gate burrs.
Mold flash, protrusion or gate burrs shall not exceed 6 mil per side .
3. Dimension "E" does not include inter-lead flash or protrusions.
Inter-lead flash and protrusions shall not exceed 10 mil per side.
Copyright  ANPEC Electronics Corp.
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APW7323/A
Package Information
TDFN3x3-10
D
E
A
b
Pin 1
A1
D2
A3
L
K
E2
Pin 1 Corner
e
S
Y
M
B
O
L
A
A1
TDFN3x3-10
MIN.
MAX.
MIN.
MAX.
0.70
0.80
0.028
0.031
0.00
0.05
0.000
0.002
0.30
0.007
0.012
0.122
A3
b
INCHES
MILLIMETERS
0.20 REF
0.18
0.008 REF
D
2.90
3.10
0.114
D2
2.20
2.70
0.087
0.106
3.10
0.114
0.122
1.75
0.055
E
2.90
E2
1.40
e
0.50 BSC
L
0.30
K
0.20
0.069
0.020 BSC
0.012
0.50
0.020
0.008
Note : 1. Followed from JEDEC MO-229 VEED-5.
Copyright  ANPEC Electronics Corp.
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APW7323/A
Carrier Tape & Reel Dimensions
P0
P2
P1
A
B0
W
F
E1
OD0
K0
A0
A
OD1 B
B
T
SECTION A-A
SECTION B-B
H
A
d
T1
Application
SOP-8P
Application
TDFN3x3-10
A
H
T1
C
d
D
W
E1
F
330.0±2.00
50 MIN.
12.4+2.00
-0.00
13.0+0.50
-0.20
1.5 MIN.
20.2 MIN.
12.0±0.30
1.75±0.10
5.5±0.05
P0
P1
P2
D0
D1
T
A0
B0
K0
1.5 MIN.
0.6+0.00
-0.40
6.40±0.20
5.20±0.20
2.10±0.20
4.0±0.10
8.0±0.10
2.0±0.05
1.5+0.10
-0.00
A
H
T1
C
d
D
W
E1
F
330.0±2.00
50 MIN.
12.4+2.00
-0.00
13.0+0.50
-0.20
1.5 MIN.
20.2 MIN.
12.0±0.30
1.75±0.10
5.5±0.05
P0
P1
P2
D0
D1
T
A0
B0
K0
4.0±0.10
8.0±0.10
2.0±0.05
1.5+0.10
-0.00
1.5 MIN.
0.6+0.00
-0.40
3.30±0.20
3.30±0.20
1.30±0.20
(mm)
Devices Per Unit
Package Type
Unit
Quantity
SOP- 8P
Tape & Reel
2500
TDFN-3x3-10
Tape & Reel
3000
Copyright  ANPEC Electronics Corp.
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APW7323/A
Taping Direction Information
SOP-8P
USER DIRECTION OF FEED
TDFN3x3-10
USER DIRECTION OF FEED
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Rev. A.5 - Aug., 2013
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APW7323/A
Classification Profile
Copyright  ANPEC Electronics Corp.
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APW7323/A
Classification Reflow Profiles
Profile Feature
Sn-Pb Eutectic Assembly
Pb-Free Assembly
100 °C
150 °C
60-120 seconds
150 °C
200 °C
60-120 seconds
3 °C/second max.
3°C/second max.
183 °C
60-150 seconds
217 °C
60-150 seconds
See Classification Temp in table 1
See Classification Temp in table 2
Time (tP)** within 5°C of the specified
classification temperature (Tc)
20** seconds
30** seconds
Average ramp-down rate (Tp to Tsmax)
6 °C/second max.
6 °C/second max.
6 minutes max.
8 minutes max.
Preheat & Soak
Temperature min (Tsmin)
Temperature max (Tsmax)
Time (Tsmin to Tsmax) (ts)
Average ramp-up rate
(Tsmax to TP)
Liquidous temperature (TL)
Time at liquidous (tL)
Peak package body Temperature
(Tp)*
Time 25°C to peak temperature
* Tolerance for peak profile Temperature (Tp) is defined as a supplier minimum and a user maximum.
** Tolerance for time at peak profile temperature (tp) is defined as a supplier minimum and a user maximum.
Table 1. SnPb Eutectic Process – Classification Temperatures (Tc)
Package
Volume mm
Thickness
<350
<2.5 mm
235 °C
≥2.5 mm
220 °C
Table 2. Pb-free Process – Classification Temperatures (Tc)
3
3
Volume mm
≥350
220 °C
220 °C
Volume mm
350-2000
260 °C
3
3
Package
Thickness
<1.6 mm
Volume mm
<350
260 °C
Volume mm
>2000
260 °C
1.6 mm – 2.5 mm
260 °C
250 °C
245 °C
≥2.5 mm
250 °C
245 °C
245 °C
3
Reliability Test Program
Test item
SOLDERABILITY
HOLT
PCT
TCT
HBM
MM
Latch-Up
Method
JESD-22, B102
JESD-22, A108
JESD-22, A102
JESD-22, A104
MIL-STD-883-3015.7
JESD-22, A115
JESD 78
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
21
Description
5 Sec, 245°C
1000 Hrs, Bias @ Tj=125°C
168 Hrs, 100%RH, 2atm, 121°C
500 Cycles, -65°C~150°C
VHBM≧2KV
VMM≧200V
10ms, 1tr≧100mA
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APW7323/A
Customer Service
Anpec Electronics Corp.
Head Office :
No.6, Dusing 1st Road, SBIP,
Hsin-Chu, Taiwan, R.O.C.
Tel : 886-3-5642000
Fax : 886-3-5642050
Taipei Branch :
2F, No. 11, Lane 218, Sec 2 Jhongsing Rd.,
Sindian City, Taipei County 23146, Taiwan
Tel : 886-2-2910-3838
Fax : 886-2-2917-3838
Copyright  ANPEC Electronics Corp.
Rev. A.5 - Aug., 2013
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