AP6508

AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Description
Pin Assignments
The AP6508 is a 500kHz switching frequency internal
compensated synchronous DCDC buck converter. It has
integrated compensation, and low RDSON high and low side
MOSFETs.
(Top View)
The AP6508 features current mode control operation, which
enables fast transient response times and easy loop
stabilization.
The AP6508 has external programmable softstart and a
Power Good indicator enabling sequencing and ramp control.
1
14
AGND
SW
2
13
GND
SW
3
12
GND
SW
4
11
VCC
SW
5
10
SS
BST
6
9
PG
EN
7
8
FB
The AP6508 simplifies board layout and reduces space
requirements with its high level of integration and minimal
need for external components, making it ideal for distributed
power architectures.
The AP6508 is available in a standard Green DFN4030-14
package with exposed PAD for improved thermal
performance and is RoHS compliant.
Applications
•
VIN 4.5V to 21V
•
•
VOUT adjustable to 0.8V
500kHz switching frequency
•
Enable pin
•
External Softstart
•
•
•
•
•
•
•
Power Good
•
Protection
o OCP
o Thermal Shutdown
Lead Free Finish/ RoHS Compliant (Note 1)
•
Note:
Exposed Pad
DFN4030-14
Features
Gaming Consoles
TV sets and Monitors
Set Top Boxes
Distributed power systems
Home Audio
Consumer electronics
1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at
http://www.diodes.com/products/lead_free.html.
Typical Application Circuit
100
VIN = 12V
VOUT = 5V
L = 3.3µH
90
EFFICIENCY (%)
NEW PRODUCT
The AP6508 enables continues load current of up to 3A with
efficiency as high as 93%.
IN
80
70
60
50
40
0
2
1
LOAD CURRENT (A)
Efficiency vs. Load Current
AP6508
Document number: DS33437 Rev. 5 - 2
3
Typical Application Circuit
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Pin Descriptions
Name
Description
Supply Voltage. The AP6508 operates from a 4.5V to 21V input rail. C1 is needed to
decouple the input rail. Use wide PCB trace to make the connection.
1
IN
2,3,4,5
SW
Switch Output. Use wide PCB trace to make the connection.
6
BST
Bootstrap. A capacitor connected between SW and BS pins is required to form a floating
supply across the high-side switch driver.
7
EN
EN=1 to enable the chip. For automatic start-up, connect EN pin to VIN by proper EN resistor
divider as Figure 1 shows.
8
FB
Feedback. An external resistor divider from the output to GND, tapped to the FB pin, sets the
output voltage. To prevent current limit run away during a short circuit fault condition the
frequency fold-back comparator lowers the oscillator frequency when the FB voltage is below
500mV.
9
PG
Power Good
10
SS
External Softstart
11
VCC
BIAS Supply. Decouple with 0.μ1F – 0.22μF cap. And the capacitance should be no more
than 0.22μF
12, 13
GND
System Ground. This pin is the reference ground for the regulated output voltage. For this
reason care must be taken in its PCB layout. Suggested to be connected to GND with copper
and vias.
14
AGND
Analog Ground
Exposed PAD
No internal connection. It is recommended to connect exposed pad to GND plane for optimal
thermal performance
Functional Block Diagram
IN 1
CURRENT SENSING
AMPLIFIER
Power Good Comparator
+
VCC 11
VCC
REGULATOR
BOOST
REGULATOR
PG 9
OSCILLATOR
CURRENT
LIMIT
COMPARATOR
EN 7
+
-
200kΩ
50pF
SS 10
+
EA
2
SW
VCC
3
LS
DRIVER
4
5
-
FB 8
+
+
-
BST
HS
DRIVER
LOGIC
1pF
REFERENCE
6
+
NEW PRODUCT
Pin #
PWM
COMPARATOR
12
GND
ERROR AMPLIFIER
13
14
AGND
AP6508
Document number: DS33437 Rev. 5 - 2
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Absolute Maximum Ratings (Note 2)
Symbol
VIN
Supply Voltage
VSW
Switch Node Voltage
VBS
VFB
VEN
Rating
Unit
22
V
-0.3 to 23
V
Bootstrap Voltage
VSW + 6
V
Feedback Voltage
–0.3V to +6
V
Enable/UVLO Voltage
–0.3V to +6
V
Comp Voltage
–0.3V to +6
V
TST
Storage Temperature
-65 to +150
°C
TJ
Junction Temperature
+150
°C
TL
Lead Temperature
+260
°C
3
300
kV
V
Rating
Unit
VCOMP
NEW PRODUCT
Parameter
ESD Susceptibility (Note 3)
HBM
MM
Human Body Model
Machine Model
Thermal Resistance (Note 4)
Symbol
Parameter
θJA
Junction to Ambient
52
°C/W
θJC
Junction to Case
11
°C/W
Recommended Operating Conditions (Note 5)
Symbol
Notes:
Parameter
Min
Max
Unit
VIN
Supply Voltage
4.5
21
V
TA
Operating Ambient Temperature Range
-40
+85
°C
2. Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings
only; functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device
reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time.
3. Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when
handling and transporting these device.
4. Test condition for SO-8EP: Device mounted on 2"*2" FR-4 substrate PC board, 2oz copper, with minimum recommended pad on top layer and
thermal vias to bottom layer ground plane.
5. The device function is not guaranteed outside of the recommended operating conditions.
AP6508
Document number: DS33437 Rev. 5 - 2
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Electrical Characteristics (VIN = 12V, TA = +25°C, unless otherwise noted)
NEW PRODUCT
Symbol
Parameter
Test Conditions
IIN
Shutdown Supply Current
VEN = 0V
IIN
Supply Current (Quiescent)
VEN = 2.0V, VFB = 1.0V
RDS(ON)1
High-Side Switch On-Resistance
(Note 6)
RDS(ON)2
Low-Side Switch On-Resistance
(Note 6)
SWLKG
Switch Leakage Current
VEN = 0V, VSW = 0V
ILimit
Current Limit
FSW
Oscillator Frequency
VFB = 0.75V
FFB
Fold-back Frequency
VFB = 300mV
DMAX
Min
Typ.
0
µA
mA
120
mΩ
20
mΩ
0
500
Maximum Duty Cycle
VFB = 700mV
80
85
TA = -40°C to +85°C
791
807
IFB
Feedback Current
VFB = 800mV
1.1
VEN_HYS
EN Threshold Hysteresis
IEN
EN Input Current
µA
A
650
kHz
fSW
0.3
Feedback Voltage
EN Rising Threshold
10
5.8
350
Unit
1.2
VFB
VEN_Rising
Max
%
823
mV
10
50
nA
1.3
1.5
V
0.4
VEN = 2V
2
VEN = 0V
0
V
μA
ENTD-Off
EN Turn Off Delay
(Note 6)
PGVth-Hi
Power Good Rising Threshold
0.9
VFB
PGVth-Lo
PGTD
VPG
IPG_LEAK
ISS
Power Good Falling Threshold
0.7
VFB
Power Good Delay
20
μs
Power Good Sink Current Capability
0.4
Power Good Leakage Current
VIN Under Voltage Threshold Rising
INUVHYS
VIN Under Voltage Threshold
Hysteresis
Note:
μA
10.5
4.0
VCC Regulator
VCC Load Regulation
TSD
V
nA
50
Soft-Start Current
INUVVth
VCC
μs
5
Icc=5mA
Thermal Shutdown
4.2
4.4
V
200
mV
5
V
5
%
140
°C
6. Guaranteed by design
AP6508
Document number: DS33437 Rev. 5 - 2
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Typical Performance Characteristics
20
SHUTDOWN SUPPLY CURRENT (µA)
QUIESCENT SUPPLY CURRENT (mA)
1.25
1.2
1.15
1.1
1.05
1
0
18
16
14
12
10
8
6
4
2
0
0
5
10
15
20
25
INPUT VOLTAGE
Quiescent Supply Current vs. Input Voltage
5
10
15
20
25
INPUT VOLTAGE (V)
Shutdown Supply Current vs. Input Voltage
7
5.05
VIN = 12V
VOUT = 1.2V
6.8
5.045
CURRENT LIMIT (A)
6.6
VCC (V)
5.04
5.035
5.03
6.4
6.2
6
5.8
5.6
5.4
5.025
5.02
5.2
0
5
VCC
10
15
20
INPUT VOLTAGE (V)
Regulator Line Regulation
5
-40 -20 -10 0 10 20 30 40 50 60 70 80 90
TEMPERATURE (°C)
Current Limit vs. Temperature
25
1.225
1.21
1.2245
1.208
1.224
1.206
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
NEW PRODUCT
1.3
1.2235
1.223
1.2225
1.222
1.2215
1.221
1.2205
VIN = 12V
1.204
1.202
VIN = 5V
1.2
1.198
1.196
1.194
1.22
0
5
10
15
20
INPUT VOLTAGE (V)
Line Regulation vs. Output Current
AP6508
Document number: DS33437 Rev. 5 - 2
25
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1.192
0
0.5
1
1.5
2
2.5
OUTPUT CURRENT (A)
Load Regulation vs. Output Current
3
October 2011
© Diodes Incorporated
AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Typical Performace Characteristics (cont.)
100
100
VOUT = 1.2V
VOUT = 1.8V
EFFICIENCY (%)
EFFICIENCY (%)
90
80
70
60
50
80
70
60
50
VIN = 12V
VIN = 5V
40
0
VIN = 12V
VIN = 5V
2
1
LOAD CURRENT (A)
Efficiency vs. Load Current
40
3
100
2
1
LOAD CURRENT (A)
Efficiency vs. Load Current
3
0
2
1
LOAD CURRENT (A)
Efficiency vs. Load Current
3
90
90
EFFICIENCY (%)
0
100
VOUT = 2.5V
80
EFFICIENCY (%)
80
70
60
70
60
50
40
30
20
50
VIN = 12V
VIN = 5V
40
0
2
1
LOAD CURRENT (A)
Efficiency vs. Load Current
100
10
0
3
VIN = 12V
VOUT = 5V
L = 3.3µH
90
EFFICIENCY (%)
NEW PRODUCT
90
80
70
60
50
40
0
2
1
LOAD CURRENT (A)
Efficiency vs. Load Current
AP6508
Document number: DS33437 Rev. 5 - 2
3
6 of 14
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Typcal Performance Characteristics
NEW PRODUCT
VIN = 12V, VOUT = 1.2V, L = 3.3µH, C1 = 22µF, C2 = 47µF, TA = +25°C, unless otherwise noted.
Time- 2µs/div
Steady State Test
IOUT = 3A
Time- 200µs/div
Load Transient Test
IOUT = 1.5A to 3A. Step at 0.8A/µs
Time- 500µs/div
Start-up Through Enable (No Load)
Time- 2ms/div
Start-up through VIN (No load)
Time- 50µs/div
Shutdown Through Enable (No Load)
Time- 50µs/div
Shutdown Through Enable (Iout =1A)
Time- 50µs/div
Short Circuit Entry
Time- 100µs/div
Short Circuit Recovery
AP6508
Document number: DS33437 Rev. 5 - 2
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© Diodes Incorporated
AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Typcal Performance Characteristics
NEW PRODUCT
VIN = 12V, VOUT = 1.2V, L = 3.3µH, C1 = 22µF, C2 = 47µF, TA = +25°C, unless otherwise noted.
Time- 1µs/div
Input Voltage Ripple
Time- 2µs/div
Output Voltage Ripple
90% of VFB
72% of VFB
Time- 1us/div
Powergood Rising Threshold
AP6508
Document number: DS33437 Rev. 5 - 2
Time- 1µs/div
Powergood FallingThreshold
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
NEW PRODUCT
Application Information
Theory of Operation
Enable
The AP6508 is a 3A current mode, synchronous buck
regulator with built in power MOSFETs. current mode
control assures excellent line and load regulation and a
wide loop bandwidth for fast response to load transients.
Figure. 2 depicts the functional block diagram of AP6508.
The enable (EN) input allows the user to control turning
on or off the converter. To enable the converter EN must
be pulled above the ‘EN Rising Threshold’ and to disable
the converter EN must be pulled below ‘EN falling
Threshold’ (EN rising threshold – EN threshold
Hysteresis).
The operation of one switching cycle can be explained as
follows. At the beginning of each cycle, HS (high-side)
MOSFET is off. The EA output voltage is higher than the
current sensing amplifier output, and the current
comparator’s output is low. The rising edge of the 500kHz
oscillator clock signal sets the RS Flip-Flop. Its output
turns on HS MOSFET. The current sensing amplifier is
reset for every switching cycle.
Few conditions on EN function:
1) EN must be pulled low for at least 5us to disable the
regulator.
2) The voltage on EN cannot exceed 5V.
3) The AP6508 can be enabled by Vin through a voltage
divider as shown in the figure 1 below.
When the HS MOSFET is on, inductor current starts to
increase. The current sensing amplifier senses and
amplifies the inductor current. Since the current mode
control is subject to sub-harmonic oscillations that peak at
half the switching frequency, slope compensation is
utilized. This will help to stabilize the power supply. This
slope compensation is summed to the current sensing
amplifier output and compared to the error amplifier output
by the PWM comparator. When the sum of the current
sensing amplifier output and the slope compensation
signal exceeds the EA output voltage, the RS Flip-Flop is
reset and HS MOSFET is turned off.
Figure 1. EN Divider Network
For one whole cycle, if the sum of the current sensing
amplifier output and the slope compensation signal does
not exceed the EA output, then the falling edge of the
oscillator clock resets the flip-flop. The output of the error
amplifier increases when feedback voltage (VFB) is lower
than the reference voltage of 0.807V. This also increases
the inductor current as it is proportional to the EA voltage.
VIN −RISE = VEN −RISE
Where VEN −RISE = 1.3V(TYP)
VIN−FALL = VEN−FALL
When the HS MOSFET turns off, the synchronous LS
MOSFET turns on until the next clock cycle begins. There
is a “dead time” between the HS turn off and LS turn on
that prevents the switches from “shooting through” from
the input supply to ground.
The voltage loop is internally compensated with the 50pF
and 200kΩ RC network. The maximum EAMP voltage
output is precisely clamped at 2.1V.
Internal Regulator
Most of the internal circuitry including the bottom driver
are powered from the 5V internal regulator. When Vin is
less than 5V, this internal regulator cannot maintain the
5V regulation and hence the output voltage would also
drop from regulation.
AP6508
Document number: DS33437 Rev. 5 - 2
(R TOP + RBOT || 1MΩ
RBOT || 1MΩ
(RTOP + RBOT || 1MΩ
RBOT || 1MΩ
Where VEN−FALL = 0.9V(TYP)
Power Good
Power Good (PGOOD) is an open drain and active high
output. This output can be pulled up high to the
appropriate level with an external resistor. The PGOOD
is flagged low when Vfb=0.7V and is an open drain
output when Vfb=0.9V. The PGOOD output can deliver
a max of 4 mA sink current at 0.4 V when de- asserted.
The PGOOD pin is held low during soft-start. Once
output voltage reaches 90% of its final value, PGOOD
goes high if there are no faults.
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Application Information (cont.)
NEW PRODUCT
External Soft Start
Soft start is traditionally implemented to prevent the
excess inrush current. This in turn prevents the converter
output voltage from overshooting when it reaches
regulation. The AP6508 has an internal current source
with a soft start capacitor to ramp the reference voltage
from 0V to 0.807V. The soft start time is internally fixed at
2ms (TYP). The soft start time can be extended > 2ms by
adding a soft start capacitor externally. The soft start
sequence is reset when there is a thermal shutdown,
Under Voltage Lockout (UVLO) or when the part is
disabled using the EN pin.
External soft start can be calculated from the formula
below:
DV
ISS = C *
DT
Where;
Iss = Soft Start Current
C = External Capacitor
DV=change in feedback voltage from 0V to maximum
voltage
DT = Soft Start Time
A hysteresis in the thermal sense circuit allows the
device to cool down to approximately 120°C before the
IC is enabled again through soft start. This thermal
hysteresis feature prevents undesirable oscillations of
the thermal protection circuit.
Setting the Output Voltage
The output voltage can be adjusted from 0.807V to 15V
using an external resistor divider. Table 1 shows a list of
resistor selection for common output voltages. Resistor
R1 is selected based on a design tradeoff between
efficiency and output voltage accuracy. For high values
of R1 there is less current consumption in the feedback
network. However the trade off is output voltage
accuracy due to the bias current in the error amplifier. R2
can be determined by the following equation:
⎛V
⎞
R1 = R 2 ⋅ ⎜⎜ OUT − 1⎟⎟
⎝ 0.807
⎠
Current Limit Protection
The AP6508 has cycle-by-cycle current limiting
implementation. The voltage drop across the internal HS
MOSFET is sensed and compared with the internally set
current limit threshold. This voltage drop is sensed at
about 30ns after the HS turns on. This voltage drop is
proportional to the peak inductor current. When the peak
inductor current exceeds the set current limit threshold,
current limit protection is activated. During this time the
feedback voltage (VFB) drops down. When the voltage at
the FB pin reaches 0.3V, the internal oscillator shifts the
frequency from the normal operating frequency of 500kHz
to a fold-back frequency of 150kHz. The current limit is
reduced to 70% of nominal current limit when the part is
operating at 150kHz. This low fold-back frequency
prevents current runaway.
Under Voltage Lockout (UVLO)
Under Voltage Lockout is implemented to prevent the
IC from operating under insufficient input voltages. The
AP6508 has a UVLO comparator that monitors the input
voltage and internal bandgap reference. If the input
voltage falls below 3.8V, the AP6508 will latch an under
voltage fault. In this event the AP6508 will be disabled
and power has to be re-cycled to reset the UVLO fault.
Figure 2. Feedback Divider Network
When output voltage is low, a T-type network as shown
in Figure 2 is recommended.
VOUT (V)
R1 (kΩ)
R2 (kΩ)
Rt (kΩ)
1.2
4.99
10.2
24.9
1.8
4.99 (1%)
4.02 (1%)
35.7
2.5
40.2 (1%)
19.1 (1%)
24.9
3.3
40.2 (1%)
13 (1%)
24.9
5
40.2 (1%)
7.68 (1%)
35.7
Table 1.Resistor Selection for Common Output
Voltages
Inductor
Calculating the inductor value is a critical factor in
designing a buck converter. For most designs, the
following equation can be used to calculate the inductor
value;
V
⋅ (VIN − VOUT )
L = OUT
VIN ⋅ ΔIL ⋅ fSW
Where ΔIL is the inductor ripple current.
Thermal Shutdown
And f SW is the buck converter switching frequency.
The AP6508 has on-chip thermal protection that prevents
damage to the IC when the die temperature exceeds safe
margins. It implements a thermal sensing to monitor the
operating junction temperature of the IC. Once the die
temperature rises to approximately 140°C, the thermal
protection feature gets activated .The internal thermal
sense circuitry turns the IC off thus preventing the power
switch from damage.
Choose the inductor ripple current to be 30% of the
maximum load current. The maximum inductor peak
current is calculated from:
ΔI
IL(MAX) = ILOAD + L
2
AP6508
Document number: DS33437 Rev. 5 - 2
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AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
Application Information (cont.)
Peak current determines the required saturation current
rating, which influences the size of the inductor.
Saturating the inductor decreases the converter
efficiency while increasing the temperatures of the
inductor and the internal MOSFETs. Hence choosing an
inductor with appropriate saturation current rating is
important.
A 1µH to 10µH inductor with a DC current rating of at
least 25% percent higher than the maximum load current
is recommended for most applications.
For highest efficiency, the inductor’s DC resistance
should be less than 200mΩ. Use a larger inductance for
improved efficiency under light load conditions.
An output capacitor with ample capacitance and low ESR
is the best option. For most applications, a 22µF ceramic
capacitor will be sufficient.
PC Board Layout
This is a high switching frequency converter. Hence
attention must be paid to the switching currents
interference in the layout. Switching current from one
power device to another can generate voltage transients
across the impedances of the interconnecting bond wires
and circuit traces. These interconnecting impedances
should be minimized by using wide, short printed circuit
traces.
The input capacitor C1
must be placed as close
as possible to the IC and
the inductor L1
Input Capacitor
The input capacitor reduces the surge current drawn from
the input supply and the switching noise from the device.
The input capacitor has to sustain the ripple current
produced during the on time on the upper MOSFET. It
must hence have a low ESR to minimize the losses.
The RMS current rating of the input capacitor is a critical
parameter that must be higher than the RMS input
current. As a rule of thumb, select an input capacitor
which has an RMS rating that is greater than half of the
maximum load current.
Due to large dI/dt through the input capacitors,
electrolytic or ceramics should be used. If a tantalum
must be used, it must be surge protected. Otherwise,
capacitor failure could occur. For most applications, a
4.7µF ceramic capacitor is sufficient.
The external feedback
resistor divider must be
placed as close as possible
to the FB pin of the IC
34mm
NEW PRODUCT
Inductor (cont.)
52mm
Output Capacitor
The output capacitor keeps the output voltage ripple
small, ensures feedback loop stability and reduces the
overshoot of the output voltage. The output capacitor is a
basic component for the fast response of the power
supply. In fact, during load transient, for the first few
microseconds it supplies the current to the load. The
converter recognizes the load transient and sets the duty
cycle to maximum, but the current slope is limited by the
inductor value.
Maximum capacitance required can be calculated from
the following equation:
ΔI
L(Iout + inductor ) 2
2
Co =
(Δ V + Vout )2 − Vout 2
AP6508 is exposed at the bottom of the package and
must be soldered directly to a well designed thermal pad
on the PCB. This will help to increase the power
dissipation.
External Bootstrap Diode
It is recommended that an external bootstrap diode be
added when the input voltage is lower than or equal to 5V
and the duty cycle is greater than 65%. This external
diode can be connected to the input or a 5V rail that is
available in the system. This helps improve the efficiency
of the converter. The bootstrap diode can be a low cost
one such as BAT54 or a Schottky that has a low Vf.
Where ΔV is the maximum output voltage overshoot.
ESR of the output capacitor dominates the output voltage
ripple. The amount of ripple can be calculated from the
equation below:
Vout capacitor = ΔIinductor * ESR
Figure 3. External Bootstrap Diode
AP6508
Document number: DS33437 Rev. 5 - 2
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© Diodes Incorporated
AP
P6508
50
00kHz 21V 3A SYNCH
HRONOUS
S DC/DC BU
UCK CONV
VERTER
Ordering Information
n
NEW PRODUCT
AP650
08 FE - 13
Package
Packing
FE
E : DFN4030
13 : Tape & Ree
el
13” Tape
T
and Reel
Pa
art Number Suffix
Device
e
Pac
ckage
Code
Pa
ackaging
(Note 7)
Qu
uantity
AP6508FE
E-13
FE
F
DFN
N4030-14
3000/Ta
ape & Reel
Note:
-13
7. Pad layout as shown on Diodes Inc. sugg
gested pad layout document
d
AP02001
1, which can be fou
und on our website at
http://www.diodes.com
m/datasheets/ap020
001.pdf.
Marking In
nformation
n
( Top View
w)
XX
Y WX
E : AP6508
8
XX : E8
Y
: 0~9
Y : Year
W : Week
W
: A~Z : 1~26 wee
ek;
a : 27~52
a~z
2 week;
z : represen
nts 52 and 53
5
X : A~Z
A
: Green
n
Part Numb
ber
P
Package
Identificatio
on Code
AP6508F
FE
DFN4030-14
E8
Package Outline
O
Dim
mensions (All Dimensio
ons in mm)
AP6508
Document numberr: DS33437 Rev. 5 - 2
11 of 14
ww
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Octtober 2011
© Diodess Incorporated
AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
NEW PRODUCT
Tape Orientation (Note 8)
Note:
8. The taping orientation of the other package type can be found on our website at http://www.diodes.com/datasheets/ap02007.pdf
AP6508
Document number: DS33437 Rev. 5 - 2
12 of 14
www.diodes.com
October 2011
© Diodes Incorporated
AP6508
500kHz 21V 3A SYNCHRONOUS DC/DC BUCK CONVERTER
IMPORTANT NOTICE
DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS
DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
NEW PRODUCT
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other
changes without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability
arising out of the application or use of this document or any product described herein; neither does Diodes Incorporated convey any
license under its patent or trademark rights, nor the rights of others. Any Customer or user of this document or products described
herein in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies
whose products are represented on Diodes Incorporated website, harmless against all damages.
Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized
sales channel.
Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall
indemnify and hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees
arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized application.
Products described herein may be covered by one or more United States, international or foreign patents pending. Product names
and markings noted herein may also be covered by one or more United States, international or foreign trademarks.
LIFE SUPPORT
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without
the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided
in the labeling can be reasonably expected to result in significant injury to the user.
B.
A critical component is any component in a life support device or system whose failure to perform can be reasonably expected
to cause the failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or
systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements
concerning their products and any use of Diodes Incorporated products in such safety-critical, life support devices or systems,
notwithstanding any devices- or systems-related information or support that may be provided by Diodes Incorporated. Further,
Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes
Incorporated products in such safety-critical, life support devices or systems.
Copyright © 2011, Diodes Incorporated
www.diodes.com
AP6508
Document number: DS33437 Rev. 5 - 2
13 of 14
www.diodes.com
October 2011
© Diodes Incorporated