AP63200/AP63201/AP63203/AP63205
3.8V TO 32V INPUT, 2A LOW IQ SYNCHRONOUS BUCK WITH ENHANCED EMI REDUCTION
Description
The AP63200/AP63201/AP63203/AP63205
is a 2A, synchronous
buck converter with a wide input voltage
range of 3.8V to 32V and
fully integrates a 125mΩ high-side power MOSFET and a 68mΩ low-
side power MOSFET to provide high-efficiency step-
down DC/DC
conversion.
The AP63200/AP63201/AP63203/AP63205 device is
easily used by
minimizing the external component count due to its adoption of peak
current mode control along with its integrat ed com pensat i on network.
The AP63200/AP 63201/AP63203/AP63205 has optimized designs for
Electromagnetic Interference (EMI) reduc
tion. The converter features
Frequency Spread Spectrum (FSS) with a switching frequency jitter of
±6%, which
reduces EMI by not allowing emi tted energy to stay in any
one frequency for a significant period of time.
It also has a proprietary
gate driver scheme to resist switching node ringing
without sacrificing
MOSFET turn-on and turn-off times, which further erases high-
frequency radiat ed EMI noise caused by MOSFET switching.
The device is available in a low-profil e, TSOT26 pack age.
Features
VIN 3.8V to 32V
2A Continuous Output Current
0.8V ± 1% Reference Voltage
22µA Ultralow Quiescent Current
Switching Frequency
o 500kHz: AP63200 and AP63201
o 1.1MHz: AP63203 and AP63205
Pulse Width Modulation (PW M) Regardless of Output Load
o AP63201
Supports Pulse Frequency Modulati on (PFM)
o AP63200, AP63203, and AP63205
o Up to 80% Efficiency at 1mA Light Load
o Up to 88% Efficiency at 5mA Light Load
Fixed Output Voltage
o 3.3V: AP63203
o 5.0V: AP63205
Proprietary Gate Dri ver Design f or Best EMI Reducti on
Frequency Spread Spect rum (FSS) to Reduce EMI
Precision Enable Threshold to Adjust UVLO
Protection Ci rcuitry
o Overvoltage Protecti on
o Cycle-by-Cycle P eak Current Limi t
o Thermal Shutdown
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Pin Assignme nts
1
2
3 4
5
6
FB
EN
VIN GND
SW
BST
TSOT26
TOP VIEW
Applications
12V and 24V Distributed Power Bus Supplies
Flat Screen TV Sets and Monitors
Power Tools and Laser Printers
White Goods and Small Home Appliances
FPGA, DSP, and ASIC Supplies
Home Audio
Network Systems
Set Top Boxes
Gaming Consoles
Consumer Electronics
Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant.
2. See https://www.diodes.com/quality/lead-free/ for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and
Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AP63200/AP63201/AP63203/AP63205
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AP63200/AP63201/AP63203/AP63205
Typical Application Circuit
AP63205
L
4.7µH
C3
100nF
C2
2x22μF
C1
10μF
3
VIN
2
EN
5
SW
6
BST
1
FB
4
GND
OUTPUT
V
OUT
5V
INPUT
Figure 1. Typical Application Circuit
Figure 2. Efficiency vs. Output Current
Pin Descriptions
Pin Num ber Pin Name Function
1 FB
Feedback sensing terminal for the output voltage. Connect this pin to the resistive divider of the output.
See
Setting the Output Voltage
section for more details.
2 EN Enable Input. EN is a digital input that turns the regulator on or off. Drive EN high to turn on the regulator and low
to turn it off. Attach to VIN or leave open for automatic startup. The EN has a precision threshold of 1.18V for
programing the UVLO. See Enable section for more details.
3 VIN
Power Input. VIN supplies the power to the IC, as well as the step-down converter switches. Drive VIN with a
3.8V to 32V power source. Bypass VIN to GND with a suitably large capacitor to eliminate noise due to the
switching of the IC. See I nput Capacitor section for more details.
4
Power Ground.
5 SW
Power Switching Output. SW is the switching node that supplies power to the output. Connect the output LC filter
from SW to the output load. Note that a capacitor is required from SW to BST to power the high-side switch.
6 BST
High-Side Gate Drive Boost Input. BST supplies the drive for the high-side N-Channel MOSFET. A 100nF
capacitor is recommended from SW to BST to power the high-side switch.
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Functional Block Diagram
0.4V
0.8V
1.1V
+
-
+
-
-
+
0.6V
+
0.8V
Internal SS Error
Amplifier
PWM
Comparator
Oscillator +
Logic
-
+
Ref OCP
7.6nF
18k
SE = 0.84V/T
RT = 0.2V/A
UVP
Q1
Q2
1
2
EN
FB
4GND
5SW
6BST
3VIN
gm
20k
+
-
Internal
Reference
VCC
Regulator
ON
1.18V
1.5µA 4µA
VSUM
COMP
CSA
Figure 3. Functional Block Diagram
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Absolute Maximum Ratings (Note 4) (@TA = +25°C, unless otherwise specified.)
Symbol
Parameter
Rating
Unit
VIN Supply Voltage -0.3 to +35.0 (DC) V
-0.3 to +40.0 (400ms) V
V
SW
Switch Node Voltage -1.0 to V
IN
+ 0.3 V
V
BST
Bootstrap Voltage V
SW
- 0.3 to V
SW
+ 6.0 V
V
FB
Feedback Voltage
-0.3V to +6.0
V
VEN
Enable/UV LO Voltage
-0.3V to +35.0
V
TST
Storage Temperature -65 to +150 °C
TJ
Junction Temperature +160 °C
TL
Lead Temperature
+260
°C
ESD Susceptibility (Note 5)
HBM
Human Body Mode
2000
V
CDM
Charge Device Model
1000
V
Notes: 4. 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.
5. 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 devices.
Thermal Resistance (Note 6)
Symbol
Parameter
Rating
Unit
θJA
Junction to Ambient TSOT26 89 °C/W
θJC
Junction to Case TSOT26 39 °C/W
Note: 6. Test condition for TSOT26: D evice mount ed on FR-4 substrate, single-layer PC board, 2oz copper, with minimum recommended pad layout.
Recommended Operating Conditions (Note 7) (@TA = +25°C, unless otherwise specified.)
Symbol
Parameter
Min
Max
Unit
V
IN
Supply Voltage
3.8
32 V
T
A
Operating Ambient Temperature Range
-40
+85
°C
Note: 7. The device function is not guaranteed outside of the recommended operating conditions.
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Electrical Characteristics (TA = +25°C, VIN = 12V, unless otherwise specified. Min/Max limits apply across the recommended
ambient temperature range, -40°C to +85°C, and input voltage range, 3.8V to 32V).
Symbol
Parameter
Test Conditions
Min
Typ
Max
Unit
ISHDN
Shutdown Supply Current
VEN = 0V
1
3
µA
IQ Supply Current (Quiescent)
AP63201:
VEN = OPEN, VFB = 1.0V
258 µA
AP63200/AP63203/AP63205:
V
EN
= OPEN , V
FB
= 1.0V 22 µA
UVLO V
IN
Under Voltage Threshold (Rising) 3.30 3.50 3.70 V
V
IN
Under Voltage Threshold Hysteresis 440 mV
RDS(ON)1
High-Side S witc h On-Resistance (Note 8)
125
m
RDS(ON)2
Low-Side Switch On-Resistance (Note 8) 68 m
IPEAK_LIMIT
HS Peak Current Limit (Note 8) 2.5 2.8 3.1 A
IVALLEY_LIMIT
LS Valley Current Limit (Note 8) 2.5 3.2 3.9 A
fSW Oscillat or Frequency
AP63200/AP63201
500
kHz
AP63203/AP63205
1100
kHz
FSS
Frequency Spread Spect rum
±6
%
tON
Minimum O n Time 80 ns
VFB Feedback Voltage
CCM, AP63200/AP63201
792
800
808
mV
CCM, AP63203
3.27
3.30
3.33
V
CCM, AP63205
4.95
5.00
5.05
V
VEN_H
EN Logic High 1.15 1.18 1.23 V
VEN_L
EN Logic Low 1.05 1.10 1.15 V
IEN EN Input Current
VEN = 1.5V
5.5 μA
VEN = 1V
1.5
μA
tSS
Soft-Start Peri od
4
ms
TSD Thermal Shutdown (Note 8) +160 °C
T
HYS
Thermal Hysteresis (Not e 8) +25 °C
Note: 8. Compliance to the datasheet limits is assured by one or more methods: production test, characterization, and/or design.
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Typical Performance Characteristics (AP63200 @TA = +25°C, VIN = 12V, VOUT = 5V, unless otherwise specifi ed. )
Figure 4. Efficiency vs. Output Current, VIN = 12V
Figure 5. Efficiency vs. Output Current, VIN = 24V
Figure 6. Load Regulation, VOUT = 5V
Figure 7. Line Regulation, VOUT = 5V
Figure 8. Feedback Voltage vs. Temperature
Figure 9. Power Switch R
DS(ON)
vs. Temperature
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Typical Performance Characteristics (continued)
Figure 10. I
Q
vs. Temperature
Figure 11. I
SHDN
vs. Temperature
Figure 12. F
SW
vs. Temperature
Figure 13. VIN POR and UVLO vs. Temperature
Figure 14. Startup using EN, Iout = 2A
Figure 15. Shutdown using EN, Iout = 2A
EN (5V/div)
VOUT (2V/div)
IL (2A/div)
SW (10V/div)
2ms/div
EN (5V/div)
VOUT (2V/div)
IL (2A/div)
SW (10V/div)
50µs/div
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Typical Performance Characteristics (continued)
Figure 16. Output Ripple, Iout = 2A
Figure 17. Load Transient, Iout = 1A to 2A
Figure 18. Output Short Prote ct i on, Iout = 2 A
Figure 19. Output Short Recovery, Iout = 2A
VOUT Ripple (20mV/div)
IL (1A/div)
SW (10V/div)
2µs/div
VOUT Ripple (500mV/div)
IOUT (1A/div)
1ms/div
VOUT (2V/div)
IL (2A/div)
SW (10V/div)
10ms/div
VOUT (2V/div)
IL (2A/div)
SW (10V/div)
10ms/div
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Appli cation Information
AP63200
AP63201
L
2.2μH
R1
30.9kΩ
R2
62kΩ
C3
100nF
C2
2x22μF
C1
10μF
3
VIN
2
EN
5
SW
6
BST
1
FB
4
GND
OUTPUT
V
OUT
1.2V
INPUT
C4
100pF
Figure 20. Typical Application Circuit of AP63200/AP63201
AP63203
AP63205
L
C3
100nF
C2
2x22μF
C1
10μF
3
VIN
2
EN
5
SW
6
BST
1
FB
4
GND
OUTPUT
V
OUT
INPUT
Figure 21. Typical Application Circuit of AP63203/AP63205
1 PWM Operation Co nt rol
The AP63200/AP63201/AP63203/AP63205 device is a 3.8V-to-32V input, 2A output, EMI friendly, fully integrated synchronous buck converter.
Refer to the bl ock diagram in Figure 3. The devi ce employs fixed-fre quency peak c urrent mode c ontrol. The internal c l ock’s rising edge (500kHz for
AP6300 and AP63201, 1.1MHz for AP63203 and AP63205) initiat es turning on the integrated high-side power MOSFET, Q1, for each cycl e. When
Q1 is on, the inductor current rises linearly, and the device charges the output capacitor. The current across Q1 is sensed and converted to a
voltage with a ratio of RT via the CS A block. The CSA output is combined with an internal slope compensation, SE, resulting in V SUM. When VSUM
rises higher than the i nternal COMP node, the device turns off Q1 and turns on the low-side power MOSFET, Q2. T he inductor current decreases
when Q2 is on. On the rising edge of next clock cycle, Q2 turns off, and Q1 turns on. This sequenc e repeats every clock cycle.
The peak current mode control with the internal loop compensation network and built-in 4ms soft-start simplifies the
AP63200/AP63201/AP63203/AP63205 footprint as well as minimizes the external component count.
The error amplif i er generates the COMP voltage by c omparing t he voltage on t he FB pin with an internal 0. 8V reference. An increase in load current
causes the feedback voltage to drop. The error amplifier thus raises the COMP voltage until the average inductor current matches the increased
load current. This feedback loop regulates the output voltage. The device also integrates internal slope compensation circuitry to prevent
subharmonic osci llat i on when the duty c ycle is great er than 50% for peak current mode control.
The AP63200/AP63201/AP63203/AP63205 device implements Frequency Spread Spectrum (FSS) with a switching frequency jitter of ±6%. FSS
reduces EMI by not allowing emitted energy to stay in any one frequency for a significant period of time. The converter further dampens high
frequency radiated EMI noise through the use of its proprietary gate driver scheme to achieve a ringing-free switching node voltage without
sacrificing the MOSFET switching times.
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Appli cation Information (continued)
In order to provide a small output ripple in light load conditions, t he AP63201 offers a fixed 500kHz switching frequenc y with FSS and Puls e Wi dth
Modulation (PW M).
The hiccup mode minim izes power dis sipation during prolonged output overcurrent or short condi tions. The hi ccup wait time is 512 cycles and the
hiccup restart time is 8192 cycles. The AP63200/AP63201/AP63203/AP63205 also features full protections including cycle-by-cycle high-side
MOSFET peak current limit, overvoltage prot ect i on, and overtemperature protection.
2 Pulse Frequency Modulation
In heavy load conditions, t he AP63200, AP63203, and AP63205 operate at forced PW M mode. The internal COMP node voltage decreases as the
load current decreases. At a certain limit, if the load current is low enough, the COMP node voltage is clamped and is prevented from decreas ing
any further. The voltage at which COMP is clamped corresponds to the 450mA peak inductor current. As the load current approaches zero, the
AP63200, AP63203, and AP63205 enter Pulse Frequency Modulat ion (PFM) to increase the converter power efficiency at light load conditions. The
AP63201 remains in continuous conduction mode at light load conditions. When the inductor current decreases to zero, zero-cross detection
circuitry on the low-side power MOSFET, Q2, forces it off until the beginning of t he next switc hing cycle. The buck converter does not sink current
from the output when the output load is light and while the device is in PFM. Because the AP63200, AP63203, and AP 63205 work in PFM during
light load conditions, they c an achieve power effici ency of up to 88% at a 5mA load condition.
The quiescent current of AP63200, AP63203 and AP63205 is 2 2μA typical under a no-load, non-switching condition.
3 Enable
When disabled, the devic e shutdown supply current is only 1μA. When applying a voltage higher t han the EN upper threshold (typical 1.18V, rising),
the AP63200/AP63201/AP63203/AP63205 enables all functions, and the device initiates the soft-start phase. The
AP63200/AP63201/AP63203/AP63205 has a built-in 4ms soft-start time to prevent output voltage overshoot and inrush current. When the EN
voltage falls bel ow its lower threshold (t ypical 1.1V, falling), the internal SS volt age is discharged to ground and device operation is disabled.
An internal 1.5µA pull-up current source connected from the internal LDO-regulated VCC to the EN pin guarantees that a high on the EN pin
automatically enables the device. For applications requiring a higher VIN UVLO voltage than is provided by the default setup, there is a 4µA
hysteresis pul l -up current source on the EN pin that configures the VIN UVLO volt age with an external resistive divider (R5 and R6) shown in Figure
22. The resistive divider resistor values are calculated by equations Eq.1 and Eq. 2.
EN 20k
+
-
ON
1.18V
I
1
1.5µA I
2
4µA
VIN
R5
R6
2
Figure 22. Programming UVLO
=.  
.
Eq. 1
=.
 . +.
Eq. 2
Where:
VON is the rising edge voltage to enable the regulator
VOFF is the falling edge voltage to disable the regulator
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Appli cation Information (continued)
Alternatively, a small ceramic capacitor can be added from EN to GND. This delays t he output startup voltage, which is useful when sequencing
multipl e power rails to minimize i nput inrush current. The amount of capacitance is calculated by equation Eq.3.
[] = . []
Eq. 3
Where:
Cd is the time delay capacitance in nF
ts is the delay time in ms
The EN pin is a high voltage pin and can be directly connected to VIN to automatically start up the device as VIN increases.
4 Undervoltage Loc kout
Undervoltage lockout is implemented to prevent the IC from insufficient input voltages. The AP63200/AP63201/AP63203/AP63205 device has a
UVLO comparator that monitors the input voltage and the internal bandgap reference. If the input voltage falls below 3.1V, the
AP63200/AP63201/AP63203/AP63205 is disabled. In this event, both the high-side and low-side power MOSFETs are turned off.
5 EMI Reduction with Frequency Spread Spectrum and Ringing-free Switching Node
In the some applications, the system must meet EMI standards. To improve EMI reduction, the AP63200/AP63201/AP63203/AP63205 adopts FSS
to spread the switching noise over a wider frequency band and therefore reduces conducted and radiated interferenc e at a particular frequency.
In buck converters, t he switching node’s (SW’s) ringi ng amplitude and cycles are critical , especially in relation to t he high frequency radiation EMI
noise. The AP63200/AP63201/AP63203/AP63205 device implements a multi-level gate driver scheme to achieve a ringing-free switching node
without sacrificing neither the switc hing node’s rise and fall slew rates nor the convert er’s power effic iency. The AP63203 and AP63205 also have
the feature to remove the resonance ringing of the SW pin when the inductor current is 0A and the device operates in PFM. The zoomed in
waveform for SW is shown in Figure 23.
Figure 23. AP63203/AP63205 SW Node Waveform
6 Overcurrent Protection
The AP63200/AP63201/AP63203/AP63205 has cycle-by-cycle peak current limit protection by sensing the current through the internal high-side
power MOSFET Q1. While Q1 is on, its c onduction current is monitored by the internal sensi ng circuitry. Once the current through Q1 exceeds the
current peak limit, Q1 immediately turns off. If Q1 consistently hits the peak current limit for 2ms, the buck converter enters hiccup mode and shuts
down. After 16ms of off time, the buck converter restarts powering up. Hiccup mode reduces t he power dissipation in the overcurrent condition.
7 Thermal Shutdown
If the juncti on t em perature of t he device reaches the thermal shut down limi t of +150°C, the AP63200/AP63201/AP63203/AP63205 shuts down both
their high-si de and low-side power MOSFETs. When the junction temperat ure reduces to the required level (+130°C nominal), the device initi ates a
normal power-up cycle with soft-start.
SW (5V/div)
IL (1A/div)
No SW Ringing
2µs/div
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Appli cation Information (continued)
8 Power Derating Characteristi cs
To prevent the regulator from exceeding the maximum junct i on temperature, some thermal analysis is required. The temperature rise is given by:
 = ()
Eq. 4
Where PD is the power dissipated by the regulator and θJA is the thermal resistance from the junction of the die to the ambient temperature.
The junction temperat ure, TJ, is given by:
=+
Eq. 5
Where TA is the ambient temperature of the environment. For the TSOT26 package, the θJA is 89 °C/W. The actual junction temperature s hould not
exceed the absolute maximum junction temperature of +125°C when considering the thermal design. A typical derating curve versus ambient
temperature is shown in Figure 24.
Figure 24. Output Current Derating Curve vs. Temperature, VIN = 12V
9 Setting the Output Voltage
The AP63203 and AP63205 have fixed output voltages of 3.3V and 5V, respectively. The AP63200 and AP63201 have adjustable output
voltages starting from 0.8V using an external resistive divider. An optional in Figure 20, of 10pF to 220pF is used to improve the transient
response. Resisto r R2 is selected based on a design tradeoff between efficiency and output voltage accuracy. There is less current consumption
in the feedback network for high values of R2. R1 can be determined by the following equation:
=(
. )
Eq. 6
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Appli cation Information (continued)
Table 1 shows a list of recommended component selections f or common output voltages for AP6300 and AP63201 referenc i ng Figure 20.
AP63200/AP63201
Output Voltage (V)
R1 (k)
R2 (k)
L (µH)
C1 (µF)
C2 (µF)
C3 (nF)
C4 (pF)
1.2
30.9
62
2.2
10
2 x 22
100
100
1.5
54.2
62
2.2
10
2 x 22
100
100
1.8
77.5
62
3.3
10
2 x 22
100
100
2.5
131
62
3.3
10
2 x 22
100
100
3.3
182
62
6.8
10
2 x 22
100
100
5
157
30
10
10
2 x 22
100
100
12
249
18
10
10
2 x 22
100
56
Table 1. Recommended Component Selections for AP63200/AP63201
Tables 2 and 3 show recommended component selections for AP63203 and AP63205 referencing Figure 21.
AP63203
Output Voltage (V)
L (µH)
C1 (µF)
C2 (µF)
C3 (nF)
3.3
3.9
10
2 x 22
100
Table 2. Recommended Component Selections for AP63203
AP63205
Output Voltage (V)
L (µH)
C1 (µF)
C2 (µF)
C3 (nF)
5
4.7
10
2 x 22
100
Table 3. Recommended Component Selections for AP63205
10 Inductor
Calculating the inductor value is a critical factor in designing a buck converter. For most designs, the following equation can be used to calc ulate
the inductor value:
=()

Eq. 7
Where ∆IL is the inductor ripple current, and fSW is the buck converter switching frequency. For AP63200/AP63201/AP63203/AP63205, choose IL
to be 30% to 50% of the maximum load current of 2A.
The inductor peak current is calculated by:
 = +
Eq. 8
Peak current determines the required saturation current rating, which influences the size of the inductor. Saturating the inductor decreases the
converter eff iciency while increas ing the temperat ures of the inductor and the internal power MOSFETs. Therefore, choosing an inductor with the
appropriate saturation current rating is important. For most applications, it is recommended to select an inductor of approximately 2.2µH to 10µH
with a DC current rating of at least 35% higher than the m aximum load current. F or highest efficiency, the inductor’s DC resistanc e should be less
than 100mΩ. Use a larger inductance for improved efficiency under light load conditions.
11 Input Capacitor
The input capacitor reduc es the surge current drawn from the input supply as well as the switc hing noise from the device. The input capacit or has
to sustain the ripple current produced during the on time of Q1. It must have a low ESR to mi nimi ze t he losses.
The RMS current rat ing of the input c apacitor is a c ritical paramet er and must be hi gher than the RMS input current . As a rule of thumb, select an
input capacitor which has an RMS rating greater than half of the maximum load current.
Due to large dI/dt through the input capacitor, electrolytic, or ceramics with l ow ES R should be used. If a tantalum capacitor is used it must be
surge protected or els e c apacitor failure could occur. Using a ceramic capacitor greater than 10µF is suffici ent f or most applicati ons.
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Appli cation Information (continued)
12 Output Capacitor
The output capacitor keeps the output voltage ripple small, ensures f eedback loop stability, and reduces the overshoot /undershoot of the output
voltage during load transients. During the first few milliseconds of a load transient, the output capacitor supplies the current to the load. The
converter recogni zes the load transi ent and sets the duty cycle to maximum but the current slope is limited by the inductor value.
The output capacitor, COUT, requirements can be calculated from equations Eq. 9 and Eq. 10.
The ESR of the output capacitor dominates the output voltage ri ppl e. The amount of ripple can be calculated from Eq. 9:
 = 
Eq. 9
An output capacitor with large capacitance and low ESR is the best option. For most applications, a 22µF to 6 8µF ceramic capac itor is sufficient.
To meet the load transient requirement, COUT should be greater than the following calc ul at ed from Eq. 10:
 >󰇡
󰇢
()
Eq. 10
Where
ΔV
is the maximum output overshoot voltage.
13 Bootstrap Capacito r
To ensure the proper operation, a ceramic capacitor must be connected between the BST and SW pins. A 100nF ceramic capacitor is sufficient. If
the BST c apacitor volt age falls below 2.3V, the boot undervoltage prot ection c ircuit turns Q2 on f or 220ns to refresh t he BST capacitor and raise its
voltage back above 2.85V. The BST capacitor voltage threshold is always maintained to ensure enough driving capability for Q1. This operation
may arise during long periods of no switching such as in PFM with light load conditions. Another event requires the refres hing of the BST capacitor
is when the input voltage drops close to the output voltage. Under this condition, the regulator enters low dropout mode by holding Q1 on for
multipl e clock cycl es. To prevent the BST capacitor from discharging, Q2 is forced to refres h. The effective dut y cycl e is approximat el y 100% so that
it acts as an LDO to maintain the output voltage regulation.
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Layout
PCB Layout
1. The AP63200/AP63201/AP63203/AP63205 device works at 2A current load, so heat dissi pation is a major concern in the layout of the P CB.
2oz copper for both the top and bottom layers is recommended.
2. Provide s uffic i ent vias for the input and output capacitors’ GND side to dissipate heat to the bottom layer.
3. Make the bottom layer under the device as the GND layer for heat dissipation. The GND layer should be as large as possible to provide
better thermal effect.
4. Place the VIN capacitors as close to the device as possible.
5. Place the feedback components as clos e t o F B as possible.
6. See Figure 25 for reference.
C1 C2
L1
C3
C4
R1
R2
VIN VOUT
SW
1
2
3 4
5
6FB
EN
VIN GND
SW
BST
GND
Figure 25. Recommended Layout
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Ordering Information
Please see http://www.diodes.com/package-outli nes. html for additional lat est inf orm ation such as Mechanical Data and Devic e Tape Orientati on.
AP6320X XX - X
Packing
Product Version Package
7 : Tape & Reel
WU : TSOT26
0: AP63200
1: AP63201
3: AP63203
5: AP63205
Part Number Mode Frequency VOUT P ackag e Co de
Tape and Reel
Quantity
Part Number Suffix
AP63200WU-7 PWM/PFM 500kHz Adjustable WU 3000 -7
AP63201WU-7 PWM Only 500kHz Adjustable WU 3000 -7
AP63203WU-7 PWM/PFM 1100kHz 3.3V WU 3000 -7
AP63205WU-7
PWM/PFM
1100kHz
5V
WU
3000
-7
Marking Information
TSOT26
123
6
7
4
XX Y WX
XX : Identification Code
Y : Year 0~9
X : Internal Code
(Top View)
5
W : Week : A~Z : 1~26 week;
a~z : 27~52 week; z represents
52 and 53 week
Part Number Package Identification Code
AP63200WU-7
TSOT26
T2
AP63201WU-7
TSOT26
T3
AP63203WU-7
TSOT26
T4
AP63205WU-7
TSOT26
T5
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Package Ou t lin e Dim en sio ns
Please see http://www.diodes.com/package-outlines.html for the latest version.
TSOT26
TSOT26
Dim
Min
Max
Typ
A
1.00
A1
0.010
0.100
A2
0.840
0.900
D
2.800
3.000
2.900
E
2.800 BSC
E1
1.500
1.700
1.600
b
0.300
0.450
c
0.120
0.200
e
0.950 BSC
e1
1.900 BSC
L
0.30
0.50
L2
0.250 BSC
θ
θ1
12°
All Dimensions in mm
Suggested Pad Layout
Please see http://www.diodes.com/package-outlines.html for the latest version.
TSOT26
Dimensions
Value (in mm)
C
0.950
X
0.700
Y
1.000
Y1
3.199
D
E1
E1/2
e1
E
E/2
e
A
A2
A1
Seating Plane
0
L2
L
Gauge Plane
01( 4x)
01( 4x)
c
b
Seating Plane
Y1
C
X
Y
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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).
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 ri ghts, nor the rights of others. Any Customer or user of this document or products descri bed herein in such applic ations 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, harml ess against all damages.
Diodes Incorporated does not warrant or acc ept any li ability whatsoever in respect of any products purchased through unauthori zed sales channel.
Should Customers purchase or use Diodes Incorporat ed 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
indirect l y, any claim of personal injury or death associat ed with such unintended or unauthorized application.
Products desc ribed herein may be covered by one or more United S tates, international or f oreign patents pending. Product names an d ma rkings
noted herein may also be covered by one or more United States, international or f orei gn trademarks.
This document is written in English but may be translated into multiple languages for reference. Only the English version of this document is the
final and determinative f orm at released by Diodes I ncorporat ed.
LIFE SU PP O R T
Diodes Incorporated products are specifical ly not authorized for use as critical components in life support devices or systems without the express
written approval of the Chief Executive Off icer of Diodes I ncorporat ed. As us ed 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 effectivenes s.
Customers represent that they have all necessary expertise in t he safety and regulatory ramif ications of their life support devices or systems, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safet y-related requirem ents 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
representati ves against any dam ages arising out of the use of Diodes Incorporat ed products i n such safety-cri tical, life support devices or systems.
Copyright © 2019, Diodes Incorporated
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