MP2388GQEU [MPS]
1A, 21V, 2MHz, High-Efficiency, Synchronous, Step-Down Converter in Ultra-Thin QFN Package;
| 型号： | MP2388GQEU |
| 厂家： | 
MONOLITHIC POWER SYSTEMS |
| 描述： | 1A, 21V, 2MHz, High-Efficiency, Synchronous, Step-Down Converter in Ultra-Thin QFN Package |
| 文件： | 总18页 (文件大小：1337K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MP2388
1A, 21V, 2MHz, High-Efficiency,
Synchronous, Step-Down Converter
in Ultra-Thin QFN Package
DESCRIPTION
FEATURES
The MP2388 is a high-frequency, synchronous,
rectified, step-down, switch-mode converter
with built-in, internal power MOSFETs. It offers
a very compact solution that achieves 1A of
continuous output current over a wide input
supply range with excellent load and line
regulation. Current mode operation provides
fast transient response and eases loop
stabilization.
•
•
•
Wide 4.5V to 21V Operating Input Range
1A Load Current
110mΩ/50mΩ Low RDS(ON) Internal Power
MOSFETs
Low Quiescent Current
High-Efficiency Synchronous Mode
Operation
Fixed 2MHz Switching Frequency
AAM Power Save Mode
Internal Soft Start
Over-Current Protection (OCP) and Hiccup
Thermal Shutdown
Output Adjustable from 0.8V
Available in a QFN-8 (1.5mmx2.5mm)
Package
•
•
•
•
•
•
•
•
•
Full protection features include over-current
protection (OCP) and thermal shutdown.
The MP2388 requires a minimum number of
readily
available,
standard,
external
components and is available in a space-saving
QFN-8 (1.5mmx2.5mm) package.
APPLICATIONS
•
•
•
Notebook Systems and I/O Power
Digital Set-Top Boxes
Flat-Panel Televisions and Monitors
All MPS parts are lead-free, halogen-free, and adhere to the RoHS
directive. For MPS green status, please visit the MPS website under Quality
Assurance. “MPS” and “The Future of Analog IC Technology” are registered
trademarks of Monolithic Power Systems, Inc.
TYPICAL APPLICATION
R5
20
19V
VIN
EN
IN
BST
SW
C5
0.1
μ
F
C1
22μ
MP2388
VOUT
F
1μH
3.3V/1A
EN
R1
75k
C2
22μ
F
VCC
FB
C4
0.1μ
R2
24k
F
AAM
GND
R3
40.2k
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
1
MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
ORDERING INFORMATION
Part Number*
Package
Top Marking
MP2388GQEU
QFN-8 (1.5mmx2.5mm)
See Below
For Tape & Reel, add suffix –Z (e.g. MP2388GQEU-Z)
TOP MARKING
EL: Product code of MP2388GQEU
Y: Year code
W: Week code
LL: Lot number
PACKAGE REFERENCE
TOP VIEW
AAM
FB
1
2
3
4
8
7
6
5
VCC
IN
EN
SW
GND
BST
QFN-8 (1.5mmx2.5mm)
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
ABSOLUTE MAXIMUM RATINGS(1)
VIN................................................ -0.3V to +28V
Thermal Resistance(5) θJA θJC
QFN-8 (1.5mmx2.5mm)….....100…..20......°C/W
V
SW .... -0.3V (-5V < 10ns) to +28V (30V < 10ns)
NOTES:
VBST .....................................................VSW + 6V
1) Exceeding these ratings may damage the device.
2) For details of EN’s ABS MAX rating, please refer to the EN
control section on page 11.
(2)
All other pins .............................. -0.3V to +6V
(3)
3) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ (MAX), the junction-to-
ambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (TJ
(MAX)-TA)/θJA. Exceeding the maximum allowable power
dissipation produces an excessive die temperature, causing
the regulator to go into thermal shutdown. Internal thermal
shutdown circuitry protects the device from permanent
damage.
Continuous power dissipation (TA = +25°C)
................................................................1.25W
Junction temperature...............................150°C
Lead temperature ....................................260°C
Storage temperature..................-65°C to 150°C
Recommended Operating Conditions(4)
Supply voltage (VIN) ...........................4.5 to 21V
Output voltage (VOUT)............... 0.8V to VIN*DMAX
Operating junction temp (TJ). ...-40°C to +125°C
4) The device is not guaranteed to function outside of its
operating conditions.
5) Measured on JESD51-7, 4-layer PCB.
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
3
MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
ELECTRICAL CHARACTERISTICS
VIN = 12V, TA = 25°C, unless otherwise noted.
Parameter
Symbol Condition
Min
Typ
Max
Units
Supply current (shutdown)
IIN
VEN = 0V
1
μA
VEN = 2V, VFB = 1V, AAM = 0.5V
VEN = 2V, VFB = 1V, AAM = 5V
0.2
0.7
110
50
Supply current (quiescent)
Iq
mA
HS switch on resistance
LS switch on resistance
Switch leakage
HSRDS-ON VBST-SW = 5V
LSRDS-ON VCC = 5V
mΩ
mΩ
μA
A
SWLKG VEN = 0V, VSW = 12V
1
Current limit
ILIMIT
fSW
Duty cycle = 40%
VFB = 750mV
VFB < 400mV
VFB = 700mV
2.4
3
2000
0.3
83
Oscillator frequency
Foldback frequency
Maximum duty cycle
Minimum on time (6)
Feedback voltage
Feedback current
EN rising threshold
EN hysteresis
1700
2400
kHz
fSW
%
fFB
DMAX
TON MIN
VFB
78
35
ns
TA = 25°C
786
798
10
810
50
mV
nA
V
IFB
VFB = 820mV
VEN RISING
VEN HYS
1.2
80
1.4
150
1.6
220
mV
V
EN = 2V
2
0
μA
EN input current
IEN
VEN = 0
nA
VIN under-voltage lockout
threshold rising
INUVVth
3.7
3.9
4.1
V
VIN under-voltage lockout
threshold hysteresis
INUVHYS
VCC
620
mV
VCC regulator
4.9
1.5
1.5
150
20
V
VCC load regulation
Soft-start period
Thermal shutdown(6)
Thermal hysteresis(6)
AAM source current
ICC = 5mA
%
TSS
VOUT from 10% to 90%
0.8
5.6
2.2
6.8
ms
°C
°C
μA
IAAM
6.2
NOTE:
6) Guaranteed by design
MP2388 Rev. 1.0
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4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 19V, VOUT = 3.3V, L = 1μH, TA = 25°C, unless otherwise noted.
MP2388 Rev. 1.0
4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 19V, VOUT = 3.3V, L = 1µH, TA = 25°C, unless otherwise noted.
MP2388 Rev. 1.0
4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 19V, VOUT = 3.3V, L = 1µH, TA = 25°C, unless otherwise noted.
MP2388 Rev. 1.0
4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 19V, VOUT = 3.3V, L = 1µH, TA = 25°C, unless otherwise noted.
MP2388 Rev. 1.0
4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
PIN FUNCTIONS
Package
Pin #
Name Description
Feedback. An external resistor divider from the output to GND tapped to FB sets the
output voltage. To prevent current limit runaway during a short-circuit fault condition, the
frequency foldback comparator lowers the oscillator frequency when the FB voltage is
below 400mV.
1
FB
Bias supply. Decouple VCC with a 0.1μF - 0.22μF capacitor. The capacitance should be
no more than 0.22μF.
2
3
4
VCC
EN
Enable. Set EN to 1 to enable the MP2388.
Bootstrap. A capacitor and a 20Ω resistor connected between SW and BST are required
to form a floating supply across the high-side switch driver.
BST
System ground. GND is the reference ground of the regulated output voltage and requires
careful consideration during PCB layout. Connect GND with coppers and vias.
5
6
7
GND
SW
IN
Switch output. Use wide PCB traces to make the connection.
Supply voltage. The MP2388 operates on a 4.5V-to-21V input rail. C1 is needed to
decouple the input rail. Use wide PCB traces to make the connection.
Advanced asynchronous modulation. A resistor connected from AAM to ground sets an
AAM voltage to force the MP2388 into non-synchronous mode when the load is small.
Drive AAM high when connected to VCC or float AAM to force the MP2388 into continuous
conduction mode (CCM).
8
AAM
MP2388 Rev. 1.0
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
BLOCK DIAGRAM
Figure 1: Functional Block Diagram
MP2388 Rev. 1.0
4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
Under light-load conditions, the value of VCOMP
is low. When VCOMP is less than VAAM and VFB is
OPERATION
The MP2388 is a high-frequency, synchronous,
rectified, step-down, switch-mode converter
with built-in, internal power MOSFETs. It offers
a very compact solution that achieves 1A of
continuous output current over a wide input
supply range with excellent load and line
regulation.
less than VREF, VCOMP ramps up until it exceeds
AAM. During this time, the internal clock is
V
blocked, so the MP2388 skips some pulses for
pulse frequency modulation (PFM) mode and
achieves light-load power save.
.
The MP2388 operates with fixed-frequency,
peak-current-control mode to regulate the
output voltage. A PWM cycle is initiated by the
internal clock. The integrated high-side power
MOSFET (HS-FET) is turned on and remains
on until its current reaches the value set by the
COMP voltage (VCOMP). When the power switch
is off, it remains off until the next clock cycle
starts. If the current in the power MOSFET does
not reach the COMP-set current value within
83% of one PWM period, the power MOSFET is
forced off.
56
260
Figure 2: Simplified AAM Control Logic
Enable (EN) Control
Enable (EN) is a digital control pin that turns the
regulator on and off. Drive EN high to turn on
the regulator; drive EN low to turn off the
regulator. There is an internal 1MΩ resistor
from EN to GND, so EN can be floated to shut
down the chip. The EN voltage is clamped at
around 6.5V by an internal Zener diode.
Connect a pull-up resistor between VIN and EN
that is large enough to limit the EN input current
below 100µA. Typically, a resistor around 100k
is sufficient for all applications.
Internal Regulator
Most of the internal circuitries are powered by
the 5V internal regulator. After EN pulls high,
this regulator takes the VIN input and operates
in the full VIN range. When VIN is greater than
5.0V, the output of the regulator is in full
regulation. When VIN is lower than 5.0V, the
output decreases. A 0.1µF ceramic capacitor is
required for decoupling.
For example, with 12V connected to VIN,
PULLUP ≥ (12V - 6.5V) ÷ 100µA = 55kΩ.
R
Connecting EN to a voltage source directly
without a pull-up resistor requires limiting the
amplitude of the voltage source to ≤6V to
prevent damage to the Zener diode (see Figure
3).
Error Amplifier (EA)
The error amplifier compares the FB voltage
with the internal 0.798V reference (REF) and
outputs a COMP voltage, which is used to
control the power MOSFET current. The
optimized internal compensation network
minimizes the external component counts and
simplifies the control loop design.
AAM Operation
Figure 3: 6.5V Zener Diode Connection
Under-Voltage Lockout (UVLO)
The MP2388 uses advanced asynchronous
modulation (AAM) power-save mode for light-
load conditions (see Figure 2). Connect a
resistor from AAM to GND to set the AAM
voltage (VAAM). Under heavy-load conditions,
Under-voltage lockout (UVLO) is implemented
to protect the chip from operating with an
insufficient supply voltage. The MP2388 UVLO
comparator monitors the output voltage of the
internal regulator (VCC). The UVLO rising
threshold is about 3.9V, while its falling
threshold is a consistent 3.25V.
VCOMP is higher than VAAM. When the clock goes
low, the HS-FET turns on and remains on until
VILsense reaches the value set by VCOMP. The
internal clock resets whenever VCOMP is higher
than VAAM
.
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
Internal Soft Start (SS)
Floating Driver and Bootstrap Charging
A soft start (SS) is implemented to prevent the
converter output voltage from overshooting
during start-up. When the chip starts up, the
internal circuitry generates a soft-start voltage
that ramps up from 0V. The soft-start period
lasts until the voltage on the soft-start capacitor
exceeds the reference voltage (0.798V). At this
point, the reference voltage takes over. The
soft-start time is internally set to around 1.5ms.
The floating power MOSFET driver is powered
by an external bootstrap capacitor. This floating
driver has its own UVLO protection. The UVLO
rising threshold is 2.2V with a hysteresis of
150mV. The bootstrap capacitor voltage is
regulated internally by VIN through D1, R5, C5,
L1, and C2 (see Figure 4). If VIN - VSW is more
than 5V, U1 regulates M1 to maintain a 5V BST
voltage across C5.
Over-Current Protection (OCP) and Hiccup
The MP2388 uses a cycle-by-cycle over-current
limit when the inductor current peak value
exceeds the set current-limit threshold.
Meanwhile, the output voltage drops until FB is
below the under-voltage (UV) threshold,
typically 50% below the reference. Once UV is
triggered, the MP2388 enters hiccup mode to
restart the part periodically. This protection
mode is especially useful when the output is
dead-shorted to ground. The average short-
circuit current is greatly reduced to alleviate
thermal issues and protect the regulator. The
MP2388 exits hiccup mode once the over-
current condition is removed.
R5
5
Figure 4: Internal Bootstrap Charging Circuit
Start-Up and Shutdown
If both VIN and EN are higher than their
appropriate thresholds, the chip starts. The
reference block starts first, generating a stable
reference voltage and current, and then the
internal regulator is enabled. The regulator
provides a stable supply for the remaining
circuitries.
Thermal Shutdown
Thermal shutdown is implemented to prevent
the chip from operating at exceedingly high
temperatures. When the silicon die temperature
is higher than 150°C, the entire chip shuts
down. When the temperature is below its lower
threshold (typically 130°C), the chip is enabled
again.
Three events can shut down the chip: EN low,
VIN low, and thermal shutdown. In the shutdown
procedure, the signaling path is first blocked to
prevent any fault triggering. VCOMP and the
internal supply rail are then pulled down. The
floating driver is not subject to this shutdown
command.
MP2388 Rev. 1.0
4/15/2016
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
PRELIMINARY SPECIFICATIONS SUBJECT TO CHANGE
Choose the inductor current to be approximately
APPLICATION INFORMATION
Setting the Output Voltage
30% of the maximum load current. The maximum
inductor peak current can be calculated with
Equation (3):
The external resistor divider is used to set the
output voltage (see Typical Application on page
1). The feedback resistor R1 also sets the
feedback loop bandwidth with the internal
compensation capacitor (see the Typical
Application on page 1). R2 can then be
calculated with Equation (1):
∆IL
IL(MAX) = ILOAD
+
(3)
2
Under light-load conditions below 100mA, a
larger inductance is recommended for improved
efficiency.
R1
VOUT
Setting the AAM Voltage
(1)
R2 =
The AAM voltage is used to set the transition
point from AAM to PWM. It should be chosen to
provide the best combination of efficiency,
stability, ripple, and transient.
−1
0.798V
The feedback network is shown in Figure 5.
If the AAM voltage is set lower, then stability and
ripple improve, but efficiency during AAM mode
and transient degrade. Likewise, if the AAM
voltage is set higher, then the efficiency during
AAM and transient improve, but stability and
ripple degrade.
Figure 5: Feedback Network
Adjust the AAM threshold by connecting a
resistor from AAM to ground (see Figure 6). An
internal 6.2µA current source charges the
external resistor.
Table 1 lists the recommended feedback
resistor values for common output voltages.
Table 1: Resistor Selection for Common Output
Voltages
VOUT (V)
1.05
1.2
R1 (kΩ)
191
R2 (kΩ)
604
AAM
3
191
383
1.8
102
82
2.5
102
47.5
24
Figure 6: AAM Network
3.3
75
Generally, R3 is can be calculated with Equation
(4):
5
100
19.1
Selecting the Inductor
(4)
VAAM = R3x6.2 A
A 0.47µH-to-4.7µH inductor with a DC current
rating at least 25% percent higher than the
maximum load current is recommended for most
applications. For the highest efficiency, the
inductor DC resistance should be less than
15mΩ. For most designs, the inductance value
can be derived from Equation (2):
The optimized AAM is shown in Figure 7.
VOUT ×(V − VOUT
)
IN
(2)
L1 =
V × ∆IL × fOSC
IN
Where ∆IL is the inductor ripple current.
MP2388 Rev. 1.0
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
The input capacitor can be electrolytic, tantalum,
or ceramic. When using electrolytic or tantalum
capacitors,
a
small, high-quality ceramic
capacitor (i.e.: 0.1μF) should be placed as close
to the IC as possible. When using ceramic
capacitors, ensure that they have enough
capacitance to provide a sufficient charge to
prevent excessive voltage ripple at input. The
input voltage ripple caused by capacitance can
be estimated with Equation (7):
ILOAD
VOUT
VOUT
(7)
∆V
=
×
× 1−
IN
fS ×C1
V
IN
V
IN
Selecting the Output Capacitor
The output capacitor (C2) is required to
maintain the DC output voltage. Ceramic,
tantalum, or low ESR electrolytic capacitors are
recommended. Use low ESR capacitors to keep
the output voltage ripple low. The output
voltage ripple can be estimated with Equation
(8):
Figure 7: AAM Selection for Common Output
Voltages
VOUT
VOUT
1
(8)
∆VOUT
=
× 1−
× R
+
ESR
fS ×L1
V
8× fS ×C2
IN
Selecting the Input Capacitor
Where L1 is the inductor value and RESR is the
equivalent series resistance (ESR) value of the
output capacitor.
The input current to the step-down converter is
discontinuous, and therefore requires
a
capacitor to supply AC current to the step-down
converter while maintaining the DC input
voltage. Use low ESR capacitors for best
performance. Ceramic capacitors with X5R or
X7R dielectrics are highly recommended
because of their low ESR and small
temperature coefficients. For most applications,
a 22µF capacitor is sufficient.
In the case of ceramic capacitors, the
impedance at the switching frequency is
dominated by the capacitance. The output
voltage ripple is mainly caused by the
capacitance. For simplification, the output
voltage ripple can be estimated with Equation
(9):
VOUT
8× fS2 ×L1 ×C2
VOUT
Since the input capacitor (C1) absorbs the input
switching current, it requires an adequate ripple
current rating. The RMS current in the input
capacitor can be estimated with Equation (5):
(9)
ΔVOUT
=
× 1−
V
IN
In the case of tantalum or electrolytic capacitors,
the ESR dominates the impedance at the
switching frequency. For simplification, the
output ripple can be approximated with
Equation (10):
VOUT
VOUT
IC1 = ILOAD
×
× 1−
(5)
V
V
IN
IN
The worst-case condition occurs at VIN = 2VOUT
shown in Equation (6):
,
VOUT
VOUT
(10)
ΔVOUT
=
× 1−
×RESR
fS ×L1
V
IN
ILOAD
IC1
=
(6)
The characteristics of the output capacitor also
affect the stability of the regulation system. The
MP2388 can be optimized for a wide range of
capacitance and ESR values.
2
For simplification, choose an input capacitor
with an RMS current rating greater than half of
the maximum load current.
MP2388 Rev. 1.0
4/15/2016
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14
PRELIMINARY SPECIFICATIONS SUBJECT TO CHANGE
External Bootstrap Diode
An external bootstrap diode may enhance the
efficiency of the regulator. The applicable
conditions of the external BST diode are:
•
VOUT is 5V or 3.3V
•
Duty cycle is high: D=
> 65%
In these cases, an external BST diode is
recommended from VCC to BST (see Figure 8).
RBST
MP2388
Figure 8: Optional External Bootstrap Diode
Added to Enhance Efficiency
The recommended external BST diode is
IN4148, and the recommended BST cap is 0.1 -
1μF.
(7)
PCB Layout Guidelines
Efficient PCB layout is critical for stable
operation. For best results, refer to Figure 9 and
follow the guidelines below.
Figure 9: Sample Board Layout
1. Keep the connection of the input ground
and GND as short and wide as possible.
Design Example
Table 2 is a design example following the
application guidelines for the specifications
below:
2. Keep the connection of the input capacitor
and IN as short and wide as possible.
3. Ensure that all feedback connections are
short and direct.
Table 2: Design Example
VIN
VOUT
IO
19V
3.3V
1A
4. Place
the
feedback
resistors
and
compensation components as close to the
chip as possible.
The detailed application schematics are shown
in Figure 10 through Figure 15. The typical
performance and circuit waveforms are shown
in the Typical Performance Characteristics
section. For more device applications, please
refer to the related evaluation board datasheets.
5. Route SW away from sensitive analog
areas, such as FB.
NOTE:
7) The recommended layout is based on the Typical Application
Circuit on page 16.
MP2388 Rev. 1.0
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MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
TYPICAL APPLICATION CIRCUITS (8)
5
20
4
5
C4
1.5µH
MP2388
5
R
54.9k
5.6pF
100k
4
6
100
3
19.1k
Figure 10: VIN = 19V, Vo = 5V, Io = 1A
5
20
4
5
C4
1µH
MP2388
3.3
R
40.2k
75k
24k
5.6pF
4
6
100
3
Figure 11: VIN = 19V, Vo = 3.3V, Io = 1A
5
20
5
C4
0.82µH
MP2388
2.5
R
28.7k
102k
5.6pF
4
6
100
47.5k
Figure 12: VIN = 19V, Vo = 2.5V, Io = 1A
TYPICAL APPLICATION CIRCUITS (continued)
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
16
MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
PRELIMINARY SPECIFICATIONS SUBJECT TO CHANGE
5
20
5
C4
0.82µH
MP2388
1.8
R
32.4k
102k
82k
5.6pF
4
6
100
Figure 13: VIN = 12V, Vo = 1.8V, Io = 1A
5
20
5
C4
0.68µH
MP2388
1.2
R
19.1k
191k
383k
5.6pF
4
100
6
Figure 14: VIN = 12V, Vo = 1.2V, Io = 1A
5
20
5
C4
0.68µH
MP2388
1.05
R
13k
191k
604k
NS
4
6
100
Figure 15: VIN = 12V, Vo = 1.05V, Io = 1A
NOTE:
8) In 12VIN to 1.05VOUT applications, the HS-FET’s on time is close to the minimum on time. Although the SW may have a little jitter, the output
voltage ripple is smaller than 15mV in PWM mode.
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
17
MP2388 – 1A, 21V, 2MHZ , HIGH-EFFICIENCY, SYNCHRONOUS, STEP-DOWN CONVERTER
PACKAGE INFORMATION
QFN-8 (1.5mmx2.5mm)
PIN 1 ID
MARKING
PIN 1 ID
0.15X45º TYP
PIN 1 ID
INDEX AREA
TOP VIEW
BOTTOM VIEW
SIDE VIEW
0.15 X 45°
NOTE:
1) ALL DIMENSIONS ARE IN
MILLIMETERS.
2) LEAD COPLANARITY SHALL BE 0.10
MILLIMETERS MAX.
3) JEDEC REFERENCE IS MO-220.
4) DRAWING IS NOT TO SCALE.
RECOMMENDED LAND PATTERN
NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third
party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not
assume any legal responsibility for any said applications.
MP2388 Rev. 1.0
4/15/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
18
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