null  User manual
AOZ2264QI-15
24V/15A Synchronous EZBuckTM Regulator
General Description
Features
The AOZ2264QI-15 is a high-efficiency, easy-to-use DC/
DC synchronous buck regulator that operates up to 24V.
The device is capable of supplying 15A of continuous
output current with an output voltage adjustable down to
0.6V (±1.0%).
 Wide input voltage range
A proprietary constant on-time PWM control with input
feed-forward results in ultra-fast transient response while
maintaining relatively constant switching frequency over
the entire input voltage range. The on-time can be
externally programmed up to 2.6µs.
– 2.7V to 24V
 15A continuous output current
 Output voltage adjustable down to 0.6V (±1.0%)
 Low RDS(ON) internal NFETs
– 9mΩ high-side
– 4mΩ low-side
 Constant On-Time with input feed-forward
 Programmable on-time up to 2.6µs
The device features multiple protection functions such as
VCC under-voltage lockout, cycle-by-cycle current limit,
output over-voltage protection, short-circuit protection,
and thermal shutdown.
 Selectable PFM light load operation
The AOZ2264QI-15 is available in a 4mm x 4mm QFN23L package and is rated over a -40°C to +85°C ambient
temperature range.
 Power Good output
 Ceramic capacitor stable
 Adjustable soft start
 Ripple reduction
 Integrated bootstrap diode
 Cycle-by-cycle current limit
 Short-circuit protection
 Thermal shutdown
 Thermally enhanced 4mm x 4mm QFN-23L package
Applications
 Portable computers
 Compact desktop PCs
 Servers
 Graphics cards
 Set-top boxes
 LCD TVs
 Cable modems
 Point-of-load DC/DC converters
 Telecom/Networking/Datacom equipment
Rev. 1.0 December 2015
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Page 1 of 16
AOZ2264QI-15
Typical Application
RTON
TON
BST
5V
VCC
R3
100kΩ
Power Good
C4
4.7μF
Input
2.7V to 24V
IN
C2
22μF
C5
0.1μF
AOZ2264QI-15
PGOOD
Off On
Output
1.05V, 15A
LX
L1
1μH
EN
R2
FB
PFM
C3
176μF
R1
AGND
SS
CSS
PGND
Power Ground
Analog Ground
Recommended Start-Up Sequence
VIN
5V
VCC
5V
EN
50μs
Ordering Information
Part Number
Ambient Temperature Range
Package
Environmental
AOZ2264QI-15
-40°C to +85°C
23-Pin 4mm x 4mm QFN
Green Product
AOS Green Products use reduced levels of Halogens, and are also RoHS compliant.
Please visit www.aosmd.com/media/AOSGreenPolicy.pdf for additional information.
Rev. 1.0 December 2015
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Page 2 of 16
AOZ2264QI-15
Option Table
All Protection
Ripple Reduction
Max. On-Time
Part Number
Auto Restart
Latch
Yes
V
V
V
AOZ2264QI-10
No
2.6µs
1.3µs
V
AOZ2264QI-11
V
AOZ2264QI-12
V
V
V
AOZ2264QI-13
V
V
AOZ2264QI-14
V
V
AOZ2264QI-15
V
V
AOZ2264QI-16
V
V
AOZ2264QI-17
V
V
V
V
V
V
V
V
SS
IN
VCC
BST
PGND
LX
Pin Configuration
23
22
21
20
19
18
PGOOD
1
17
LX
EN
2
16
LX
15
PGND
PFM 3
LX
IN
5
13
PGND
TON
6
12
PGND
7
8
9
10
11
LX
FB
LX
PGND
IN
14
IN
4
IN
AGND
23-Pin 4mm x 4mm QFN
(Top View)
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Page 3 of 16
AOZ2264QI-15
Pin Description
Pin Number
Pin Name
Pin Function
1
PGOOD
Power Good Signal Output. PGOOD is an open-drain output used to indicate the status
of the output voltage. It is internally pulled low when the output voltage is 15% lower than
the nominal regulation voltage for or 20% higher than the nominal regulation voltage.
PGOOD is pulled low during soft-start and shut down.
2
EN
3
PFM
4
AGND
5
FB
6
TON
7, 8, 9, 22
IN
12, 13, 14, 15, 19
PGND
Power Ground.
10, 11, 16, 17, 18
LX
Switching Node.
20
BST
Bootstrap Capacitor Connection. The AOZ2264QI-15 includes an internal bootstrap
diode. Connect an external capacitor between BST and LX as shown in the Typical Application diagram.
21
VCC
Supply Input for analog functions. Bypass VCC to AGND with a 1µF~10µF ceramic
capacitor. Place the capacitor close to VCC pin.
23
SS
Soft-Start Time Setting Pin. Connect a capacitor between SS and AGND to set the
soft-start time.
Rev. 1.0 December 2015
Enable Input. The AOZ2264QI-15 is enabled when EN is pulled high. The device shuts
down when EN is pulled low.
PFM Selection Input. Connect PFM pin to VCC for forced PWM operation. Connect PFM
pin to ground for PFM operation to improve light load efficiency.
Analog Ground.
Feedback Input. Adjust the output voltage with a resistive voltage-divider between the
regulator’s output and AGND.
On-Time Setting Input. Connect a resistor between VIN and TON to set the on time.
Supply Input. IN is the regulator input. All IN pins must be connected together.
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Page 4 of 16
AOZ2264QI-15
Absolute Maximum Ratings
Maximum Operating Ratings
Exceeding the Absolute Maximum Ratings may damage the
device.
Parameter
Rating
Parameter
IN, TON to AGND
-0.3V to 26V
LX to AGND(2)
-0.3V to 26V
BST to AGND
-0.3V to 32V
SS, PGOOD, FB, EN, VCC, PFM to AGND
+150°C
Storage Temperature (TS)
-65°C to +150°C
(1)
2.7V to 24V
Output Voltage Range
0.6V to 0.85*VIN
Ambient Temperature (TA)
-40°C to +85°C
Package Thermal Resistance
(θJA)
-0.3V to +0.3V
Junction Temperature (TJ)
Rating
Supply Voltage (VIN)
-0.3V to 6V
PGND to AGND
ESD Rating
The device is not guaranteed to operate beyond the
Maximum Operating Ratings.
40°C/W
2kV
Note:
1. Devices are inherently ESD sensitive, handling precautions are
required. Human body model rating: 1.5kΩ in series with 100pF.
2. LX to PGND Transient (t<20ns) ------ -7V to VIN + 7V.
Electrical Characteristics
TA = 25°C, VIN = 12V, VCC = 5V, EN = 5V, unless otherwise specified. Specifications in BOLD indicate a temperature range of
-40°C to +85°C.
Symbol
VIN
Parameter
Conditions
IN Supply Voltage
Min.
Typ.
2.7
Max
Units
24
V
VCC rising
VCC falling
4.2
3.9
V
V
Quiescent Supply Current of VCC
IOUT = 0A, VEN > 2V, PFM
mode
0.15
mA
IOFF
Shutdown Supply Current
VEN = 0V
VFB
Feedback Voltage
TA = 25°C
TA = 0°C to 85°C
VUVLO
Under-Voltage Lockout Threshold
Iq
IFB
0.594
0.591
1
20
µA
0.600
0.600
0.606
0.609
V
V
Load Regulation
0.5
%
Line Regulation
1
%
FB Input Bias Current
200
nA
0.5
V
V
Enable
VEN
EN Input Threshold
VEN_HYS
EN Input Hysteresis
Off threshold
On threshold
1.6
100
mV
PFM Control
VPFM
PFM Input Threshold
VPFMHYS
PFM Input Hysteresis
PFM Mode threshold
Force PWM threshold
0.5
2.5
V
V
100
mV
200
ns
100
ns
Modulator
TON
On Time
RTON = 100kΩ, VIN = 12V
TON_MIN
Minimum On Time
TON_MAX
Maximum On Time
2.6
µs
TOFF_MIN
Minimum Off Time
300
ns
Rev. 1.0 December 2015
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Page 5 of 16
AOZ2264QI-15
Electrical Characteristics (Continued)
TA = 25°C, VIN = 12V, VCC = 5V, EN = 5V, unless otherwise specified. Specifications in BOLD indicate a temperature range of
-40°C to +85°C.
Symbol
Parameter
Conditions
Min.
Typ.
Max
Units
7
11
15
µA
0.5
V
±1
µA
Soft-Start
ISS_OUT
SS Source Current
VSS = 0V
CSS = 0.001µF to 0.1µF
Power Good Signal
VPG_LOW
PGOOD Low Voltage
IOL = 1mA
PGOOD Leakage Current
VPGH
PGOOD Threshold
(Low Level to High Level)
FB rising
90
%
VPGL
PGOOD Threshold
(High Level to Low Level)
FB rising
FB falling
120
85
%
%
5
%
70
%
32
µs
120
%
9
mΩ
PGOOD Threshold Hysteresis
Under Voltage and Over Voltage Protection
VPL
Under Voltage Threshold
TPL
Under Voltage Delay Time
VPH
Over Voltage Threshold
FB falling
FB rising
Power Stage Output
RDS(ON)
RDS(ON)
High-Side NFET On-Resistance
VIN = 12V, VCC = 5V
High-Side NFET Leakage
VEN = 0V, VLX = 0V
Low-Side NFET On-Resistance
VLX = 12V, VCC = 5V
Low-Side NFET Leakage
VEN = 0V
10
4
µA
mΩ
10
µA
Over-current and Thermal Protection
ILIM
Current Limit
VCC = 5V
Thermal Shutdown Threshold
TJ rising
TJ falling
Rev. 1.0 December 2015
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20
A
150
100
°C
°C
Page 6 of 16
AOZ2264QI-15
Functional Block Diagram
BST
IN
PGood
VCC
EN
UVLO
Reference
& Bias
TOFF_MIN
Q
Timer
Error Comp
0.6V
SS
ISENCE
(AC)
FB
PG Logic
S
Q
R
FB
Decode
LX
ILIM Comp
ILIM
Current
Information
Processing
ISENSE
OTP
ISENSE
ISENSE (AC)
Vcc
TON
Q
Timer
PFM
TON
EN
TON
Generator
Light Load
Threshold
Light Load
Comp
ISENSE
PGND
Rev. 1.0 December 2015
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AGND
Page 7 of 16
AOZ2264QI-15
Typical Performance Characteristics
Circuit of Typical Application. TA = 25°C, VIN = 19V, VOUT = 1.05V, fs = 500kHz unless otherwise specified.
Load Transient 0A to 15A
Normal Operation
VLX
10V/div
ILX
5A/div
ILX
5A/div
Vo ripple
50mV/div
Vo ripple
10mV/div
5μs/div
500μs/div
Full Load Start-up
Short Circuit Protection
VLX
20V/div
VLX
20V/div
EN
5V/div
lLX
10A/div
ILX
10A/div
Vo
1V/div
Vo
500mV/div
1ms/div
Rev. 1.0 December 2015
20μs/div
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Page 8 of 16
AOZ2264QI-15
Detailed Description
The AOZ2264QI-15 is a high-efficiency, easy-to-use,
synchronous buck regulator optimized for notebook
computers. The regulator is capable of supplying 15A of
continuous output current with an output voltage
adjustable down to 0.6V. The programmable on-time
from 100ns to 2.6µs, enables optimizing the configuration
for PCB area and efficiency.
The input voltage of AOZ2264QI-15 can be as low as
2.7V. The highest input voltage of AOZ2264QI-15 can be
24V. Constant on-time PWM with input feed-forward
control scheme results in ultra-fast transient response
while maintaining relatively constant switching frequency
over the entire input range. True AC current mode control
scheme guarantees the regulator can be stable with a
ceramic output capacitor. The switching frequency can
be externally programmed. Protection features include
VCC under-voltage lockout, current limit, output over
voltage and under voltage protection, short-circuit
protection, and thermal shutdown.
The AOZ2264QI-15 is available in 23-pin 4mm x 4mm
QFN package.
Enable and Soft Start
The AOZ2264QI-15 has external soft start feature to limit
in-rush current and ensure the output voltage ramps up
smoothly to regulation voltage. A soft start process
begins when VCC rises to 4.5V and voltage on EN pin is
HIGH. An internal current source charges the external
soft start capacitor; the FB voltage follows the voltage of
soft start pin (VSS) when it is lower than 0.6V. When VSS
is higher than 0.6V, the FB voltage is regulated by
internal precise band-gap voltage (0.6V). When VSS is
higher than 3.3V, the PGOOD signal is high. The soft
start time can be calculated by the following formula:
TSS(µs) = 330 x CSS(nF)
If CSS is 1nF, the soft start time will be 330µs; if CSS is
10nF, the soft start time will be 3.3ms.
VOUT
Constant-On-Time PWM Control with Input
Feed-Forward
The control algorithm of AOZ2264QI-15 is constant-ontime PWM Control with input feed-forward.
The simplified control schematic is shown in Figure 2.
IN
PWM
–
Programmable
One-Shot
FB Voltage/
AC Current
Information
Comp
+
0.6V
Figure 2. Simplified Control Schematic of AOZ2264QI-15
The high-side switch on-time is determined solely by a
one-shot whose pulse width can be programmed by one
external resistor and is inversely proportional to input
voltage (IN). The one-shot is triggered when the internal
0.6V is lower than the combined information of FB
voltage and the AC current information of inductor, which
is processed and obtained through the sensed lower-side
MOSFET current once it turns on. The added AC current
information can help the stability of constant-on time
control even with pure ceramic output capacitors, which
have very low ESR. The AC current information has no
DC offset, which does not cause offset with output load
change, which is fundamentally different from other V2
constant-on time control schemes.
The constant-on-time PWM control architecture is a
pseudo-fixed frequency with input voltage feed-forward.
The internal circuit of AOZ2264QI-15 sets the on-time of
high-side switch inversely proportional to the IN.
R TON ( Ω )
T ON ∝ ------------------------V IN ( V )
(1)
To achieve the flux balance of inductor, the buck
converter has the equation:
V OUT
F SW = --------------------------V IN × T ON
(2)
VSS
Once the product of VIN x TON is constant, the switching
frequency keeps constant and is independent with input
voltage.
VSS=3.3V
VSS=0.6V
PGOOD
An external resistor between the IN and TON pin sets the
switching on-time according to the following curves:
Figure 1. Soft Start Sequence of AOZ2264QI-15
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Page 9 of 16
AOZ2264QI-15
constant-on-time control is significantly improved even
without the help of output capacitor’s ESR, and thus the
pure ceramic capacitor solution can be applicable. The
pure ceramic capacitor solution can significantly reduce
the output ripple (no ESR caused overshoot and
undershoot) and less board area design.
On-Time vs. On-Time Resistance
On-Time (nS)
(@ VIN=5V~15V)
1130
1064
998
932
866
800
734
668
602
536
470
404
338
272
206
140
VIN=5V
VIN=7V
VIN=9V
VIN=11V
VIN=13V
VIN=15V
Current-Limit Protection
60
74
88
102
116
130
144
158
172
186
The AOZ2264QI-15 uses the current-limit protection by
using RDSON of the lower MOSFET current sensing. To
detect real current information, a minimum constant-off
(300ns typical) is implemented after a constant-on time. If
the current exceeds the current-limit threshold, the PWM
controller is not allowed to initiate a new cycle. The actual
peak current is greater than the current-limit threshold by
an amount equal to the inductor ripple current. Therefore,
the exact current-limit characteristic and maximum load
capability are a function of the inductor value as well as
input and output voltages. The current limit will keep the
low-side MOSFET ON and will not allow another highside on-time, until the current in the low-side MOSFET
reduces below the current limit.
200
On-Time Resistance (KΩ)
On-Time vs. On-Time Resistance
On-Time (nS)
(@ VIN=17V~28V)
315
299
283
267
251
235
219
203
187
171
155
139
123
107
91
75
VIN=17V
VIN=19V
VIN=21V
VIN=24V
VIN=26V
VIN=28V
60
74
88
102
116
130
144
158
172
186
After 64 switching cycles, the AOZ2264QI-15 considers
this is a true failed condition and therefore, turns-off both
high-side and low-side MOSFETs and shuts down. The
AOZ2264QI-15 enters hiccup mode to periodically restart
the part. When current limit protection is removed, the
AOZ2264QI-15 exits hiccup mode.
200
On-Time Resistance (KΩ)
Figure 3. TON vs. RTON Curves for AOZ2264QI-15
Output Voltage Under-Voltage Protection
A further simplified equation will be:
V OUT ( V )
6
F SW ( kHz ) = ------------------------------------------------ × 10
V IN ( V ) × T ON ( ns )
(3)
If VOUT is 1.05V, VIN is 19V, and set FS = 500kHz.
According to equation 3, TON = 110ns is needed. Finally,
use the TON to RTON curve, we can find out RTON is
82kΩ.
If the output voltage is lower than 70% by over-current or
short circuit, the AOZ2264QI-15 will wait for 32µs
(typical) and turns-off both high-side and low-side
MOSFETs and shuts down. When the output voltage
under-voltage protection is removed, the AOZ2264QI-15
restarts again.
Output Voltage Over-Voltage Protection
This algorithm results in a nearly constant switching
frequency despite the lack of a fixed-frequency clock
generator.
The threshold of OVP is set 20% higher than 0.6V. When
the VFB voltage exceeds the OVP threshold, the highside MOSFET is turned-on at 1µs, then shuts down.
When the output voltage over-voltage protection is
removed, the AOZ2264QI-15 restarts again.
True Current Mode Control
Power Good Output
The constant-on-time control scheme is intrinsically
unstable if output capacitor’s ESR is not large enough as
an effective current-sense resistor. Ceramic capacitors
usually cannot be used as output capacitor.
The power good (PGOOD) output, which is an open
drain output, requires the pull-up resistor. When the
output voltage is 15% below than the nominal regulation
voltage, the PGOOD is pulled low. When the output
voltage is 20% higher than the nominal regulation
voltage, the PGOOD is also pulled low.
The AOZ2264QI-15 senses the low-side MOSFET
current and processes it into DC and AC current
information using AOS proprietary technique. The AC
current information is decoded and added on the FB pin
on phase. With AC current information, the stability of
Rev. 1.0 December 2015
When combined with the under-voltage-protection circuit,
this current limit method is effective in almost every
circumstance.
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Page 10 of 16
AOZ2264QI-15
Application Information
The basic AOZ2264QI-15 application circuit is shown in
page 2. Component selection is explained below.
Input Capacitor
The input capacitor must be connected to the IN pins and
PGND pin of the AOZ2264QI-15 to maintain steady input
voltage and filter out the pulsing input current. A small
decoupling capacitor, usually 1µF, should be connected
to the VCC pin and AGND pin for stable operation of the
AOZ2264QI-15. The voltage rating of input capacitor
must be greater than maximum input voltage plus ripple
voltage.
The input ripple voltage can be approximated by
equation below:
Inductor
The inductor is used to supply constant current to output
when it is driven by a switching voltage. For given input
and output voltage, inductance and switching frequency
together decide the inductor ripple current, which is:
VO  VO
IO

ΔV IN = ----------------- ×  1 – --------- × --------V IN V IN
f × C IN 
Since the input current is discontinuous in a buck
converter, the current stress on the input capacitor is
another concern when selecting the capacitor. For a buck
circuit, the RMS value of input capacitor current can be
calculated by:
VO 
VO 
I CIN_RMS = I O × ---------  1 – ---------
V IN 
V IN
VO 
VO 
ΔI L = ----------- ×  1 – ---------
V IN
f×L 
The peak inductor current is:
ΔI L
I Lpeak = I O + -------2
if let m equal the conversion ratio:
VO
-------- = m
V IN
The relation between the input capacitor RMS current
and voltage conversion ratio is calculated and shown in
Figure 4. It can be seen that when VO is half of VIN, CIN is
under the worst current stress. The worst current stress
on CIN is 0.5 x IO.
High inductance gives low inductor ripple current but
requires a larger size inductor to avoid saturation. Low
ripple current reduces inductor core losses. It also
reduces RMS current through inductor and switches,
which results in less conduction loss. Usually, peak to
peak ripple current on inductor is designed to be 30% to
50% of output current.
When selecting the inductor, make sure it is able to
handle the peak current without saturation even at the
highest operating temperature.
The inductor takes the highest current in a buck circuit.
The conduction loss on the inductor needs to be checked
for thermal and efficiency requirements.
0.5
0.4
Surface mount inductors in different shapes and styles
are available from Coilcraft, Elytone and Murata.
Shielded inductors are small and radiate less EMI noise,
but they do cost more than unshielded inductors. The
choice depends on EMI requirement, price and size.
ICIN_RMS(m) 0.3
IO
0.2
0.1
0
For reliable operation and best performance, the input
capacitors must have current rating higher than ICIN-RMS
at worst operating conditions. Ceramic capacitors are
preferred for input capacitors because of their low ESR
and high ripple current rating. Depending on the
application circuits, other low ESR tantalum capacitor or
aluminum electrolytic capacitor may also be used. When
selecting ceramic capacitors, X5R or X7R type dielectric
ceramic capacitors are preferred for their better
temperature and voltage characteristics. Note that the
ripple current rating from capacitor manufactures is
based on certain amount of life time. Further de-rating
may be necessary for practical design requirement.
0
0.5
m
1
Figure 4. ICIN vs. Voltage Conversion Ratio
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Page 11 of 16
AOZ2264QI-15
Output Capacitor
The output capacitor is selected based on the DC output
voltage rating, output ripple voltage specification and
ripple current rating.
The selected output capacitor must have a higher rated
voltage specification than the maximum desired output
voltage including ripple. De-rating needs to be
considered for long term reliability.
Output ripple voltage specification is another important
factor for selecting the output capacitor. In a buck converter circuit, output ripple voltage is determined by
inductor value, switching frequency, output capacitor
value and ESR. It can be calculated by the equation
below:
1
ΔV O = ΔI L ×  ESR CO + -------------------------

8×f×C 
O
where,
CO is output capacitor value, and
ESRCO is the Equivalent Series Resistor of output capacitor.
When a low ESR ceramic capacitor is used as output
capacitor, the impedance of the capacitor at the
switching frequency dominates. Output ripple is mainly
caused by capacitor value and inductor ripple current.
The output ripple voltage calculation can be simplified to:
1
ΔV O = ΔI L × ------------------------8 × f × CO
If the impedance of ESR at switching frequency
dominates, the output ripple voltage is mainly decided by
capacitor ESR and inductor ripple current. The output
ripple voltage calculation can be further simplified to:
ΔV O = ΔI L × ESR CO
Thermal Management and Layout
Consideration
In the AOZ2264QI-15 buck regulator circuit, high pulsing
current flows through two circuit loops. The first loop
starts from the input capacitors, to the VIN pin, to the LX
pins, to the filter inductor, to the output capacitor and
load, and then returns to the input capacitor through
ground. Current flows in the first loop when the high side
switch is on. The second loop starts from the inductor, to
the output capacitors and load, to the low side switch.
Current flows in the second loop when the low side
switch is on.
In PCB layout, minimizing the two loops area reduces the
noise of this circuit and improves efficiency. A ground
plane is strongly recommended to connect the input
capacitor, output capacitor and PGND pin of the
AOZ2264QI-15.
In the AOZ2264QI-15 buck regulator circuit, the major
power dissipating components are the AOZ2264QI-15
and output inductor. The total power dissipation of the
converter circuit can be measured by input power minus
output power.
P total_loss = V IN × I IN – V O × I O
The power dissipation of inductor can be approximately
calculated by output current and DCR of inductor and
output current.
P inductor_loss = IO2 × R inductor × 1.1
The actual junction temperature can be calculated with
power dissipation in the AOZ2264QI-15 and thermal
impedance from junction to ambient.
T junction = ( P total_loss – P inductor_loss ) × Θ JA
For lower output ripple voltage across the entire
operating temperature range, X5R or X7R dielectric type
of ceramic, or other low ESR tantalum are recommended
to be used as output capacitors.
The maximum junction temperature of AOZ2264QI-15 is
150ºC, which limits the maximum load current capability.
In a buck converter, output capacitor current is
continuous. The RMS current of output capacitor is
decided by the peak to peak inductor ripple current.
It can be calculated by:
The thermal performance of the AOZ2264QI-15 is
strongly affected by the PCB layout. Extra care should be
taken by users during design process to ensure that the
IC will operate under the recommended environmental
conditions.
ΔI L
I CO_RMS = ---------12
Usually, the ripple current rating of the output capacitor is
a smaller issue because of the low current stress. When
the buck inductor is selected to be very small and
inductor ripple current is high, the output capacitor could
be overstressed.
Rev. 1.0 December 2015
www.aosmd.com
Page 12 of 16
AOZ2264QI-15
Layout Considerations
Several layout tips are listed below for the best electric
and thermal performance.
1. The LX pins and pad are connected to internal low
side switch drain. They are low resistance thermal
conduction path and most noisy switching node.
Connect a large copper plane to LX pin to help
thermal dissipation.
5. Voltage divider R1 and R2 should be placed as close
as possible to FB and AGND.
6. RTON should be connected as close as possible to
Pin 6 (TON pin).
7. A ground plane is preferred; Pin 19 (PGND) must be
connected to the ground plane through via.
2. The IN pins and pad are connected to internal high
side switch drain. They are also low resistance
thermal conduction path. Connect a large copper
plane to IN pins to help thermal dissipation.
8. Keep sensitive signal traces such as feedback trace
far away from the LX pins.
9. Pour copper plane on all unused board area and
connect it to stable DC nodes, like VIN, GND or
VOUT.
3. Input capacitors should be connected to the IN pin
and the PGND pin as close as possible to reduce the
switching spikes.
4. Decoupling capacitor CVCC should be connected to
VCC and AGND as close as possible.
Vout
%67
3*1'
/;
PGND
PGND
9&&
/;
ġġġġġġġġġġġġġġġġġġġġ
/;
/;
/;
PGND
/;
,1
Vin
,1
,1
,1
66
3*22'
PGND
PGND
(1
3)0
$*1'
)%
721
,1
,
Vout
Rev. 1.0 December 2015
www.aosmd.com
Page 13 of 16
AOZ2264QI-15
Package Dimensions, QFN 4x4B, 23 Lead EP2_S
D
D2
D3
Pin #1 Dot
By Marking
L1
L
e
E
E1
E3
E2
b
L4
L2
L3
D1
D1
TOP VIEW
BOTTOM VIEW
A1
A
A2
SIDE VIEW
RECOMMENDED LAND PATTERN
0.37
0.25
0.25
0.50
0.22
0.45
2.75
3.10
3.10
3.43
0.04
0.25
0.75
1.34
0.37
0.75
0.95
UNIT: MM
Dimensions in inches
Dimensions in millimeters
Symbols
Min.
Typ.
Max.
Symbols
Min.
Typ.
Max.
A
A1
A2
E
E1
E2
E3
D
D1
D2
D3
L
L1
L2
L3
L4
b
e
0.80
0.00
0.90
—
0.2 REF
4.00
3.05
1.75
3.05
4.00
0.75
0.95
1.34
0.40
0.62
0.28
0.62
0.35
0.25
0.50 BSC
1.00
0.05
A
A1
A2
E
E1
E2
E3
D
D1
D2
D3
L
L1
L2
L3
L4
b
e
0.031
0.000
0.035
—
0.008 REF
0.157
0.120
0.069
0.120
0.157
0.030
0.037
0.053
0.016
0.024
0.011
0.024
0.014
0.010
0.020 BSC
0.039
0.002
3.90
2.95
1.65
2.95
3.90
0.65
0.85
1.24
0.35
0.57
0.23
0.57
0.30
0.20
4.10
3.15
1.85
3.15
4.10
0.85
1.05
1.44
0.45
0.67
0.33
0.67
0.40
0.30
0.153
0.116
0.065
0.116
0.153
0.026
0.033
0.049
0.014
0.022
0.009
0.022
0.012
0.008
0.161
0.124
0.073
0.124
0.161
0.034
0.041
0.057
0.018
0.026
0.013
0.026
0.016
0.012
Notes:
1. Controlling dimensions are in millimeters. Converted inch dimensions are not necessarily exact.
2. Tolerance: ± 0.05 unless otherwise specified.
3. Radius on all corners is 0.152 max., unless otherwise specified.
4. Package wrapage: 0.012 max.
5. No plastic flash allowed on the top and bottom lead surface.
6. Pad planarity: ± 0.102
7. Crack between plastic body and lead is not allowed.
Rev. 1.0 December 2015
www.aosmd.com
Page 14 of 16
AOZ2264QI-15
Tape and Reel Dimensions, QFN 4x4
Carrier Tape
P1
P2
D1
T
E1
E2
E
B0
K0
D0
P0
A0
Feeding Direction
UNIT: mm
Package
A0
B0
K0
D0
QFN 4x4
(12mm)
4.35
±0.10
4.35
±0.10
1.10
±0.10
1.50
Min.
D1
E
1.50
+0.10/-0
12.00
±0.30
Reel
E1
E2
P0
P1
P2
T
1.75
±0.10
5.50
±0.05
8.00
±0.10
4.00
±0.10
2.00
±0.05
0.30
±0.05
W1
S
G
N
M
K
V
R
H
W
UNIT: mm
Tape Size Reel Size
12mm
ø330
M
ø330.0
±2.0
N
ø79.0
±1.0
W
12.4
+2.0/-0.0
W1
17.0
+2.6/-1.2
H
ø13.0
±0.5
K
10.5
±0.2
S
2.0
±0.5
G
—
R
—
V
—
Leader/Trailer and Orientation
Trailer Tape
300mm min.
Rev. 1.0 December 2015
Components Tape
Orientation in Pocket
www.aosmd.com
Leader Tape
500mm min.
Page 15 of 16
AOZ2264QI-15
Part Marking
AOZ2264QI-15
(QFN4x4)
Z2264QIF
Part Number Code
FAYWLT
Assembly Lot Code
Fab & Assembly Location
Year & Week Code
Part Number
Part Number Code of Marking
AOZ2264QI-10
AOZ2264QI-11
AOZ2264QI-12
AOZ2264QI-13
AOZ2264QI-14
AOZ2264QI-15
AOZ2264QI-16
AOZ2264QI-17
Z2264QIA
Z2264QIB
Z2264QIC
Z2264QID
Z2264QIE
Z2264QIF
Z2264QIG
Z2264QIH
LEGAL DISCLAIMER
Alpha and Omega Semiconductor makes no representations or warranties with respect to the accuracy or
completeness of the information provided herein and takes no liabilities for the consequences of use of such
information or any product described herein. Alpha and Omega Semiconductor reserves the right to make changes
to such information at any time without further notice. This document does not constitute the grant of any intellectual
property rights or representation of non-infringement of any third party’s intellectual property rights.
LIFE SUPPORT POLICY
ALPHA AND OMEGA SEMICONDUCTOR PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL
COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS.
As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant into
the body or (b) support or sustain life, and (c) whose
failure to perform when properly used in accordance
with instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of
the user.
Rev. 1.0 December 2015
2. A critical component in any component of a life
support, device, or system whose failure to perform can
be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or
effectiveness.
www.aosmd.com
Page 16 of 16
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