MPQ8616
The Future of Analog IC Technology
FEATURES
The MPQ8616 is fully integrated high frequency
synchronous rectified step-down switch mode
converter. It offers very compact solutions to
achieve 6A/12A output current from a 3V to 6V
input with excellent load and line regulation.
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DESCRIPTION
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High Efficiency, 6A/12A, 6V
Synchronous Step-down Converter
Constant-On-Time (COT) control mode provides
fast transient response and eases loop
stabilization. The MPQ8616 can operate with a
low-cost electrolytic capacitor and can support
ceramic output capacitor with external slope
compensation.
Operating frequency is programmed by an
external resistor and is compensated for
variations in VIN. It is almost constant with all the
input voltage and output load conditions.
Under voltage lockout is internally set at 2.8 V,
but can be increased by programming the
threshold with a resistor network on the enable
pin. The output voltage startup ramp is controlled
by the soft start pin. A power good signal
indicates the output is within its nominal voltage
range.
Full fault protection including OCP, SCP, OVP
UVP and OTP is provided by internal
comparators.
The MPQ8616 requires a minimum number of
readily available standard external components and
are available in QFN3x4 packages.
1.5V to 6V Wide Input Range
3 V to 6V VCC Operating Supply
6A/12A Output Current
Low RDS(ON) Internal Power MOSFETs
Proprietary
Switching
Loss
Reduction
Technique
Adaptive COT for Ultrafast Transient
Response
1% Reference Voltage Over -20C to +85C
Junction Temperature Range
Programmable Soft Start Time
Pre-Bias Start up
Programmable Switching Frequency from
300kHz to 1MHz.
Minimum On Time TON_MIN=60ns
Minimum Off Time TOFF_MIN=100ns
Non-latch OCP, non-latch OVP Protection
and Thermal Shutdown
Output Adjustable from 0.61V to 4.5V
APPLICATIONS
Telecom System Base Stations
Networking Systems
Server
Personal Video Recorders
Flat Panel Television and Monitors
Distributed Power Systems
All MPS parts are lead-free, halogen free, and adhere to the RoHS
directive. For MPS green status, please visit MPS website under Quality
Assurance. “MPS” and “The Future of Analog IC Technology” are
Registered Trademarks of Monolithic Power Systems, Inc.
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TYPICAL APPLICATION
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
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© 2019 MPS. All Rights Reserved.
1
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
ORDERING INFORMATION
Package
Top Marking
MPQ8616GL-6
QFN (3x4mm)
MP8616
6
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Part Number*
MPQ8616GL-12
MP8616
12
QFN (3x4mm)
* For Tape & Reel, add suffix –Z (e.g. MPQ8616GL-6/12–Z);
PACKAGE REFERENCE
TOP VIEW
FB
2
SS
3
EN
4
VCC
PG
IN
12
11
10
FB
2
SS
3
EN
4
5
VCC
5
6
PG
6
13
14
SW
1
SW
AGND
7
8
9
BST
GND
GND
FREQ
IN
IN
12
11
10
13
14
7
8
BST
GND
SW
1
IN
SW
AGND
TOP VIEW
FREQ
9
GND
EXPOSED PAD
ON BACKSIDE
EXPOSED PAD
ON BACKSIDE
Part Number**
Package
Part Number**
Package
MPQ8616GL-6
QFN14 (3x4mm)
MPQ8616GL-12
QFN14 (3x4mm)
*** For Tape & Reel, add suffix –Z (eg. MPQ8616GL-12–Z)
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** For Tape & Reel, add suffix –Z (eg. MPQ8616GL-6–Z)
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
2
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance (4)
Supply Voltage VIN ....................................... 6.5V
VSW ........................................ -0.3V to VIN + 0.3V
VSW (30ns) ................................... -3V to VIN + 3V
VIN -VSW ................................. -0.3V to VIN + 0.3V
VIN -VSW (30ns) ............................ -3V to VIN + 3V
VBST........................................................ VSW + 6V
All Other Pins .................................. -0.3V to +6V
Continuous Power Dissipation (TA=+25) (2)……
QFN(3x4mm)…………………...……………2.6W
Junction Temperature ............................... 150C
Lead Temperature .................................... 260C
Storage Temperature ................-65C to +150C
QFN (3mmx4mm) ................... 48 ....... 10 ... C/W
θJC
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θJA
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Notes:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ(MAX), the junction-toambient 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
will cause excessive die temperature, and the regulator will go
into thermal shutdown. Internal thermal shutdown circuitry
protects the device from permanent damage.
3) The device is not guaranteed to function outside of its
operating conditions.
4) Measured on JESD51-7, 4-layer PCB.
Recommended Operating Conditions (3)
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Input Supply Voltage VIN .................... 1.5V to 6V
VCC Supply Voltage Vcc ....................... 3V to 6V
Output Voltage VOUT ...................... 0.61V to 4.5V
Operating Junction Temp. (TJ). -40°C to +125°C
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
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© 2019 MPS. All Rights Reserved.
3
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
ELECTRICAL CHARACTERISTICS
VIN = 5V, TJ = -40 to +125C, unless otherwise noted.
IIN
IIN
Condition
Min
VEN = 0V
VEN = 2V, VFB = 1V
0.6
Typ
Max
Units
1
1.05
2
1.3
μA
mA
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Supply Current
Supply Current (Shutdown)
Supply Current (Quiescent)
MOSFET
Symbol
R
Parameters
High-side Switch On Resistance
HSRDS-ON
Low-side Switch On Resistance
LSRDS-ON
Switch Leakage
SWLKG
MPQ8616-6, TJ =25C
19.8
MPQ8616-12, TJ =25C
16
mΩ
MPQ8616-6 TJ =25C
15.3
MPQ8616-12, TJ =25C
8.4
VEN = 0V, VSW = 0V or 5V
0.01
3
mΩ
μA
Current Limit
High-side Current Limit
ILIMIT
Timer
One-Shot On Time
tON
Minimum Off Time
tOFF
Fold back Timer(5)
tFOLDBACK
Over-voltage and Under-voltage Protection
OVP Threshold
VOVP
(5)
OVP Delay
tOVP
(5)
UVP Threshold
VUVP
Reference And Soft Start
Reference Voltage
IFB
ISS
9.5
12
14.5
MPQ8616-12
17
23
27
50
200
100
2.5
RFREQ=165kΩ,VOUT=1.2V
OCP happens
150
110%
120%
1
50%
130%
TJ = -20C to +85C
604
610
616
TJ = -40C to +125C
VFB = 610mV
VSS=0V
601
610
619
5
0.001
7.5
150
10
A
ns
ns
μs
V
μs
VREF
mV
nA
μA
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Feedback Current
Soft Start Charging Current
VREF
MPQ8616-6
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
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© 2019 MPS. All Rights Reserved.
4
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Enable And UVLO
Enable Input Low Voltage
Enable Hysteresis
VILEN
VEN-HYS
Condition
Min
Typ
Max
Units
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Parameters
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VIN = 5V, TJ = -40 to +125C, unless otherwise noted.
Enable Input Current
VCC UVLO
VCC Under Voltage Lockout
Threshold Rising
VCC Under Voltage Lockout
Threshold Hysteresis
Power Good
Power Good Rising Threshold
Power Good Falling Threshold
Power Good Deglitch Timer
Power Good Sink Current
Capability
Power Good Leakage Current
Thermal Protection
Thermal Shutdown
Thermal Shutdown Hysteresis
IEN
1.4
VEN = 2V
VEN = 0V
VCCVth
2.3
VCCHYS
84%
63%
TSS=1ms,
VPG
Sink 4mA
IPG_LEAK
VPG = 3.3V
Note 5
μA
2.8
2.95
V
90%
70%
2000
50
150
V
mV
2
1
300
PGVth-Hi
PGVth-Lo
PGTd
TSD
1.8
890
1.5
0.01
mV
96%
73%
5000
VREF
VREF
μs
0.4
V
150
nA
160
25
°C
°C
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Note:
5) Guaranteed by design.
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
5
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL CHARACTERISTICS
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MPQ8616, Performance waveforms are tested on the evaluation board of the Design Example
section.
1150
0.9
25
0.8
0.7
20
1100
0.6
15
0.5
1050
0.4
0.3
10
0.2
1000
0.1
5
0
-0.1
-50
0
50
100
150
950
-50
0
50
100
150
12
23.20
615
10
23.00
614
22.80
613
8
6
0
0
50
100
150
21.80
-50
0
50
100
150
607
-50
7.60
205
7.50
121.4
200
7.40
121.2
195
7.30
190
7.20
185
7.10
180
7.00
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121.8
O
121.6
121.0
120.8
120.6
120.4
120.2
120.0
-50
0
50
100
150
175
-50
0
50
100
150
0
50
100
608
210
122.0
150
609
22.00
-50
100
610
22.20
2
50
611
22.40
4
0
612
22.60
N
0
-50
0
50
100
150
6.90
-50
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
150
6
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL CHARACTERISTICS (continued)
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MPQ8616GL, Performance waveforms are tested on the evaluation board of the Design Example
section.
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
7
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
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Performance waveforms are tested on the evaluation board of the Design Example section.
MPQ8616GL-6, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
97
97
95
95
93
93
91
91
89
89
87
87
85
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
85
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
96
95
94
93
92
91
90
89
88
100
97
92
97
94
OUTPUT CURRENT (A)
94
98
95
87
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
96
99
96
96
90
95
88
94
92
93
92
84
91
91
82
90
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
OUTPUT CURRENT (A)
90
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
OUTPUT CURRENT (A)
80
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
OUTPUT CURRENT (A)
98
97
97
95
95
93
93
91
91
89
89
87
87
85
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
85
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
T
93
96
O
94
92
90
N
97
88
86
84
82
80
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
OUTPUT CURRENT (A)
86
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
8
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
R
Performance waveforms are tested on the evaluation board of the Design Example section.
MPQ8616GL-6, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
Load Regulation
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Line Regulation
100
0.60
0.6
99
0.40
98
0.4
IOUT=0A
97
0.20
96
95
0.2
IOUT=3A
0.00
0
94
-0.20
93
92
-0.40
91
1.5 2.5 3.5 4.5 5.5
OUTPUT CURRENT (A)
-0.60
6.5
650
1200
FREQUENCY (kHz)
1000
800
600
400
200
400
600
4
5
-0.6
0
6
1
800 1000 1200
Frequency vs.
Input Voltage
One-Shot-On Time
vs. VIN
590
570
3
3.5
4
4.5
5
5.5
6
T
6
580
570
560
550
0
1
2
3
4
LOAD CURRENT (A)
Supply Current (Quiescent)
vs. VCC Voltage
Supply Current (Shutdown)
vs. Temperature
1.0
O
0.5
1000
700
N
5
590
1100
800
900
600
0.0
800
500
700
400
300
6
600
610
1200
5
610
630
550
3
4
IOUT (A)
Frequency vs.
Load Current
INPUT VOLTAGE (V)
900
2
VIN (V)
Frequency vs. RFREQ
0
200
3
-0.4
FREQUENCY (kHz)
90
0.5
FREQUENCY (kHz)
-0.2
IOUT=6A
-0.5
600
3
3.5
4
4.5
5
VIN (V)
5.5
6
500
3
3.5
4
4.5
5
5.5
6
-1.0
3
3.5
4
4.5
5
5.5
6
VCC VOLTAGE (V)
MPQ8616 Rev. 1.2
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1/9/2019
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9
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
R
Performance waveforms are tested on the evaluation board of the Design Example section.
MPQ8616GL-6, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
Dead Time (off)
Input/Output Voltage Ripple
IOUT = 6A
IOUT = 6A
IOUT = 0A
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Dead Time (on)
VOUT(AC)
10mV/div.
VIN(AC)
10mV/div.
VSW
1V/div.
VSW
500mV/div.
VSW
5V/div.
IL
2A/div.
Input/Output Voltage Ripple
Input/Output Voltage Ripple
IOUT = 0.3A
IOUT = 6A
Power Good through
VIN Start-Up
IOUT = 6A
VOUT(AC)
10mV/div.
VOUT(AC)
10mV/div.
VIN(AC)
10mV/div.
VIN(AC)
50mV/div.
VSW
5V/div.
VSW
5V/div.
IL
2A/div.
VIN
2V/div.
VPG
2V/div.
IL
5A/div.
Power Good through
VIN Shutdown
T
IOUT = 6A
Power Good through
EN Start-Up
Power Good through
EN Shutdown
IOUT = 6A
IOUT = 6A
VOUT
1V/div.
VOUT
1V/div.
VIN
2V/div.
VEN
5V/div.
VEN
5V/div.
VPG
2V/div.
VPG
5V/div.
VPG
5V/div.
O
N
VOUT
1V/div.
VOUT
1V/div.
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
10
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
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Performance waveforms are tested on the evaluation board of the Design Example section.
MPQ8616GL-6, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
VOUT
1V/div.
VOUT
1V/div.
VOUT
1V/div.
VIN
5V/div.
VSW
5V/div.
VIN
5V/div.
VSW
5V/div.
VIN
5V/div.
VSW
5V/div.
IL
2A/div.
IL
5A/div.
IL
2A/div.
VOUT
1V/div.
VOUT
1V/div.
VOUT
1V/div.
VIN
5V/div.
VSW
5V/div.
VEN
5V/div.
VSW
5V/div.
VIN
5V/div.
IL
5A/div.
IL
2A/div.
VSW
5V/div.
VOUT
1V/div.
VOUT
1V/div.
VIN
5V/div.
VEN
5V/div.
VSW
5V/div.
IL
5A/div.
VSW
5V/div.
N
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T
IL
5A/div.
IL
5A/div.
VOUT(AC)
50mV/div.
IL
50mA/div.
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
11
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
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Performance waveforms are tested on the evaluation board of the Design Example section.
MPQ8616GL-6, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
VOUT
1V/div.
VSW
5V/div.
VOUT
1V/div.
VSW
5V/div.
VSW
5V/div.
IL
5A/div.
IL
5A/div.
N
O
T
IL
5A/div.
VOUT
1V/div.
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
12
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
97
95
97
96
95
95
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N O
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O
97
R
MPQ8616GL-12, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
93
94
93
93
91
92
91
89
91
89
87
90
89
85
87
83
85
0 1 2 3 4 5 6 7 8 9 10 11 12 13
OUTPUT CURRENT (A)
0 1 2 3 4 5 6 7 8 9 10 1112 13
OUTPUT CURRENT (A)
88
87
97
100
96
96
99
94
95
98
92
97
90
96
88
95
86
90
94
84
89
93
82
88
92
94
93
92
91
0 1 2 3 4 5 6 7 8 9 10 1112 13
80
OUTPUT CURRENT (A)
98
97
97
95
95
93
93
91
91
89
89
87
87
96
O
94
92
N
90
88
86
84
82
80
0 1 2 3 4 5 6 7 8 9 10 111213
OUTPUT CURRENT (A)
85
0 1 2 3 4 5 6 7 8 9 10 111213
OUTPUT CURRENT (A)
0 1 2 3 4 5 6 7 8 9 10 111213
OUTPUT CURRENT (A)
T
OUTPUT CURRENT (A)
0 1 2 3 4 5 6 7 8 9 10 111213
0 1 2 3 4 5 6 7 8 9 10 11 12 13
OUTPUT CURRENT (A)
85
0 1 2 3 4 5 6 7 8 9 10 11 12 13
OUTPUT CURRENT (A)
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
13
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
MPQ8616GL-12, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
0.6
0.6
0.4
0.4
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100
99
Load Regulation
R
Line Regulation
98
IOUT=0A
0.2
97
96
0.2
0
0.0
95
-0.2
94
93
92
-0.4
91
90
0 1 2 3 4 5 6 7 8 9 10 1112 13
OUTPUT CURRENT (A)
-0.2
IOUT=12A
-0.4
IOUT=6A
-0.6
-0.8
-0.6
3
3.5
4 4.5
5
5.5
INPUT VOLTAGE (V)
6
-0.8
0
2
4
6
8
10
LOAD CURRENT (A)
12
Switching Frequency
vs. Load Current
650
650
640
645
630
640
620
610
635
600
590
630
580
625
570
3
3.5
4
4.5
5 5.5
INPUT VOLTAGE (V)
6
560
0
2
4
6
8
10
LOAD CURRENT (A)
12
N
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620
MPQ8616 Rev. 1.2
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
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MPQ8616GL-12, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
MPQ8616 Rev. 1.2
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
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MPQ8616GL-12, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
MPQ8616 Rev. 1.2
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
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MPQ8616GL-12, VIN=5V, VOUT=1.2V, L=1.0µH, TA=+25°C, unless otherwise noted.
MPQ8616 Rev. 1.2
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
PIN FUNCTIONS
R
MPQ8616GL-6, MPQ8616GL-12
Name
Description
1
AGND
2
FB
3
SS
4
EN
5
VCC
6
PG
7
BST
8-9
GND
10-11
IN
12
FREQ
13-14
SW
Analog ground.
Feedback. An external resistor divider from the output to GND, tapped to the FB pin, sets
the output voltage. It is recommended to place the resistor divider as close to FB pin as
possible. Vias should be avoided on the FB traces.
Soft Start. Connect on external capacitor to program the soft start time for the switch
mode regulator.
Enable pin. Pull this pin higher than 1.8V to enable the chip. For automatic start-up,
connect EN pin to VIN with 100KΩ resistor.
Can be used to set the on/off threshold (adjust UVLO) with two additional resistors.
When the nominal VOUT is higher than 2.5V, EN should be pulled low before VIN
powers off.
External bias supply voltage for driver and control circuits. For 1.5V to 3V input
application, provide VCC with separate 3.3V/5V bias supply. For 3V to 6V input
application, provide VCC with separate 3.3V/5V bias supply or tie VCC to VIN with
10ohm resistor. Decouple with a minimum 4.7µF ceramic capacitor as close to the pin as
possible. X7R or X5R grade dielectric ceramic capacitors are recommended for their
stable temperature characteristics.
Power good output. It is high if the output voltage is higher than 90% of the nominal
voltage. There is a delay from FB ≥ 90% to PG goes high.
Bootstrap. A capacitor connected between SW and BS pins is required to form a floating
supply across the high-side switch driver.
System Ground. This pin is the reference ground of the regulated output voltage. For this
reason care must be taken in PCB layout.
Supply Voltage. The IN pin supplies power for internal MOSFET and regulator. The
MPQ8616 operate from a +3V to +6V input rail. An input capacitor is needed to decouple
the input rail. Use wide PCB traces and multiple vias to make the connection.
Frequency setting pin. A resistor connected between FREQ and IN is required to set the
switching frequency. The ON time is determined by the input voltage and the resistor
connected to the FREQ pin. IN connect through a resistor is used for line feed-forward
and makes the frequency basically constant during input voltage’s variation. Recommend
a 10pF decoupling capacitor from FREQ to GND.
Switch Output. Connect this pin to the inductor and bootstrap capacitor. This pin is driven
up to the VIN voltage by the high-side switch during the on-time of the PWM duty cycle.
The inductor current drives the SW pin negative during the off-time. The on-resistance of
the low-side switch and the internal Schottky diode fixes the negative voltage. Use wide
PCB traces to make the connection.
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PIN #
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
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BLOCK DIAGRAM
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Figure 1—Functional Block Diagram
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
OPERATION
the HS-MOSFET is turned off, the LS-MOSFET
is turned on until next period.
For the MPQ8616 is operated in CCM, the
switching frequency is fairly constant and it is
called PWM mode.
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The MPQ8616 is fully integrated synchronous
rectified step-down switch mode converter.
Constant-on-time (COT) control is employed to
provide fast transient response and easy loop
stabilization. At the beginning of each cycle, the
high-side MOSFET (HS-FET) is turned ON when
the feedback voltage (VFB) is below the reference
voltage (VREF), which indicates insufficient output
voltage. The ON period is determined by the
input voltage and the frequency-set resistor as
follows:
R
PWM Operation
t ON (ns)
4.8 RFREQ (k )
VIN (V) 0.49
(1)
After the ON period elapses, the HS-FET is
turned off, or becomes OFF state. It is turned ON
again when VFB drops below VREF. By repeating
operation this way, the converter regulates the
output voltage. The integrated low-side MOSFET
(LS-FET) is turned on when the HS-FET is in its
OFF state to minimize the conduction loss. There
will be a dead short between input and GND if
both HS-FET and LS-FET are turned on at the
same time. It’s called shoot-through. In order to
avoid shoot-through, a dead-time (DT) is
internally generated between HS-FET off and LSFET on, or LS-FET off and HS-FET on.
Switching Frequency
The selection of switching frequency is a tradeoff
between efficiency and component size. Low
frequency operation increases efficiency by
reducing MOSFET switching losses, but requires
larger inductance and capacitance to maintain
low output voltage ripple.
For MPQ8616 ， the on time can be set using
FREQ pin, then the frequency is set in steady
state operation at CCM mode.
Adaptive constant-on-time (COT) control is used
in MPQ8616 and there is no dedicated oscillator
in the IC. Connect FREQ pin to IN pin through
resistor RFREQ and the input voltage is feedforwarded to the one-shot on-time timer through
the resistor RFREQ. When in steady state
operation at CCM, the duty ratio is kept as
VOUT/VIN. Hence the switching frequency is fairly
constant over the input voltage range. The
switching frequency can be set as follows:
106
(2)
fSW (kHz)
4.8 RFREQ (k) VIN (V)
tDELAY (ns)
VIN (V) 0.49
VOUT (V)
O
T
Where tDELAY is the comparator delay. It’s about
40ns.
Figure 2—PWM Operation
N
MPQ8616 always operating in continuousconduction-mode (CCM), which means the
inductor current can go negative at light load.
The CCM mode operation is shown in Figure2.
When VFB is below VREF, HS-MOSFET is turned
on for a fixed interval which is determined by
one- shot on-timer as equation 1 shown. When
Generally, the MPQ8616 is set for 300kHz to
1MHz application. It is optimized to operate at
high switching frequency with high efficiency.
High switching frequency makes it possible to
utilize small sized LC filter components to save
system PCB space.
Jitter and FB Ramp Slope
Figure 3 shows jitter occurring in PWM mode.
When there is noise in the VFB downward slope,
the ON time of HS-FET deviates from its
intended location and produces jitter. It is
necessary to understand that there is a
relationship between a system’s stability and the
steepness of the VFB ripple’s downward slope.
The slope steepness of the VFB ripple dominates
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
L
SW
Vo
R4
C4
IR4
IC4
R9
R1
I FB
R
in noise immunity. The magnitude of the VFB
ripple doesn’t affect the noise immunity
directly.
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Ceramic
FB
R2
Figure 5—Simplified Circuit in PWM Mode
with External Ramp Compensation
Figure 3—Jitter in PWM Mode
Ramp with Large ESR Capacitor
In the case of POSCAP or other types of
capacitor with lager ESR is applied as output
capacitor, the ESR ripple dominates the output
ripple, and the slope on the FB is quite ESR
related. Figure 4 shows an equivalent circuit in
PWM mode with the HS-FET off and without an
external ramp circuit. Turn to application
information section for design steps with large
ESR capacitors.
SW
FB
R1
Figure 4—Simplified Circuit in PWM Mode
without External Ramp Compensation
O
T
To realize the stability when no external ramp is
applied, usually the ESR value should be chosen
as follow:
(3)
TSW is the switching period.
N
1 R1 R2
R9
20 R1 R 2
(4)
Where:
IR4 IC4 IFB IC4
(5)
R1 // R2
VIN VO
t ON
R 4 C4
R1 // R2 R9
(6)
The downward slope of the VFB ripple then
follows:
POSCAP
RESR
2 fSW C4
VRAMP
ESR
R2
t SW
t
ON
0.7 2
COUT
1
And the ramp on the VFB can then be estimated
as:
Vo
L
In PWM mode, an equivalent circuit with HS-FET
off and the use of an external ramp
compensation circuit (R4, C4) is simplified in
Figure 5. The external ramp is derived from the
inductor ripple current. If one chooses C4, R9,
R1 and R2 to meet the following condition:
Ramp with Small ESR Capacitor
When the output capacitors are ceramic ones,
the ESR ripple is not high enough to stabilize the
system, and external ramp compensation is
needed. Skip to application information section
for design steps with small ESR caps.
VSLOPE1
VOUT
VRAMP
t off
R 4 C4
(7)
As can be seen from equation 7, if there is
instability in PWM mode, we can reduce either
R4 or C4. If C4 can not be reduced further due to
limitation from equation 4, then we can only
reduce R4. For a stable PWM operation, the
Vslope1 should be design follow equation 8.
t SW
t
ON RESR COUT
0.7 IO 103
VSLOPE1 0.7 2
VOUT
2 L COUT
t sw t on
(8)
Where Io is the load current.
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
Over-Current Protection (OCP)
The MPQ8616 employs soft start/stop (SS)
mechanism to ensure smooth output during
power up and power down.
The MPQ8616 enters over-current protection
mode when the inductor current hits the current
limit, and tries to recover from over-current fault
with hiccup mode. That means in over-current
protection, the chip will disable output power
stage, discharge soft-start capacitor and then
automatically try to soft-start again. If the overcurrent condition still holds after soft-start ends,
the chip repeats this operation cycle till overcurrent disappears and output rises back to
regulation level. The MPQ8616 also operates in
hiccup mode when short circuit happens.
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When the EN pin becomes high, an internal
current source (8μA) charges up the SS capacitor
C6. The SS capacitor voltage takes over the REF
voltage to the PWM comparator. The output
voltage smoothly ramps up with the SS voltage.
Once the SS voltage reaches the same level as
the REF voltage, it keeps ramping up while VREF
takes over the PWM comparator. At this point,
the soft start finishes and it enters into steady
state operation.
R
Soft Start/Stop
When the EN pin is pulled to low, the SS CAP
voltage is discharged through an 8uA internal
current source. Once the SS voltage reaches
REF voltage, it takes over the PWM comparator.
The output voltage will decrease smoothly with
SS voltage until zero level. The SS capacitor
value can be determined as follows:
CSS (nF)
t SS (ms) ISS (A)
VREF
(9)
If the output capacitors have large capacitance
value, it’s not recommended to set the SS time
too small. Otherwise, it’s easy to hit the current
limit during SS. A minimum value of 4.7nF should
be used if the output capacitance value is larger
than 330μF.
T
Pre-Bias Startup
If the output is pre-biased to a certain voltage
during startup, the MPQ8616 will disable the
switching of both high-side and low-side switches
until the voltage on the internal soft-start
capacitor exceeds the sensed output voltage at
the FB pin.
N
O
Power Good (PG)
The MPQ8616 has power-good (PG) output. It
can be connected to VCC or other voltage source
through a resistor (e.g. 100k). When the
MPQ8616 is powered on and FB voltage reaches
above 90% of REF voltage, the PG pin is pulled
high.
When the FB voltage drops to 70% of REF
voltage or the part is not powered on, the PG pin
will be pulled low.
Over/Under –Voltage Protection (OVP/UVP)
The MPQ8616 has non-latching over voltage
protection. It monitors the output voltage through
a resistor divider feedback (FB) voltage to detect
over-voltage on the output. When the FB voltage
is higher than 120% of the REF voltage (0.610V),
the LS-FET will be turned on while the HS-FET
will be off. The LS-FET keeps on until it hits the
negative current limit and turns off for 100ns. If
over voltage condition still holds, the chip repeats
this operation cycle till the FB voltage drops
below 110% of the REF voltage.
When the FB voltage is below 50% of the REF
voltage (0.610V), it is recognized as undervoltage (UV). Usually, UVP accompanies a hit in
current limit and results in OCP.
Configuring the EN Control
The EN pin provides electrical on/off control of
the device. Set EN high to turn on the regulator
and low to turn it off. Do not float this pin.
For automatic start-up, the EN pin can be pulled
up to input voltage through a resistive voltage
divider. Choose the values of the pull-up resistor
(RUP from VIN pin to EN pin) and the pull-down
resistor (RDOWN from EN pin to GND) to
determine the automatic start-up voltage:
VINSTART 1.4
RUP RDOWN
RDOWN
(10)
For example, for RUP =100kΩ and RDOWN =51kΩ,
the VINSTART is set at 4.15V.
To avoid noise, a 10nF ceramic capacitor from
EN to GND is recommended.
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
R
UVLO protection
The MPQ8616 has under-voltage lock-out
protection (UVLO). When the VCC voltage is
higher than the UVLO rising threshold voltage,
the MPQ8616 will be powered up. It shuts off
when the VCC voltage is lower than the UVLO
falling threshold voltage. This is non-latch
protection.The MPQ8616 is disabled when the
VCC voltage falls below its UVLO falling
threshold (2.45V). If an application requires a
higher under-voltage lockout (UVLO), use the EN
pin as shown in Figure 7 to adjust the input
voltage UVLO by using two external resistors. It
is recommended to use the enable resistors to
set the UVLO falling threshold (VSTOP) above 2.8
V. The rising threshold (VSTART) should be set to
provide enough hysteresis to allow for any input
supply variations.
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There is an internal zener diode on the EN pin,
which clamps the EN pin voltage to prevent it
from running away. The maximum pull up current
assuming a worst case 6V internal zener clamp
should be less than 1mA. Therefore, when EN is
driven by an external logic signal, the EN voltage
should be lower than 6V; when EN is connected
with VIN through a pull-up resistor or a resistive
voltage divider, the resistance selection should
ensure the maximum pull up current less than
1mA.
If using a resistive voltage divider and VIN higher
than 6V, the allowed minimum pull-up resistor
RUP should meet the following equation:
VIN (V) 6
6
1(mA)
RUP (k ) RDOWN (k )
(11)
As a result, when just the pull-up resistor RUP is
applied, the VINSTART is determined by input
UVLO. The value of RUP can be got as:
RUP (k)
VIN (V) 6
1(mA)
IN
VCC
MPQ8616
(12)
A typical pull-up resistor is 100kΩ.
When the nominal VOUT is higher than 2.5V, to
avoid the converter operation with minimum off
time during power off, EN should be pulled low
before VIN powers off. Figure 6 shows the
recommended power off sequence.
R UP
EN Comparator
EN
RDOWN
Figure 7—Adjustable UVLO
O
T
When the nominal VOUT is higher than 2.5V, EN
should be pulled low before VIN powers off.
Thermal Shutdown
Thermal shutdown is employed in the MPQ8616.
The junction temperature of the IC is internally
monitored. If the junction temperature exceeds
the threshold value (minimum 150ºC), the
converter shuts off. This is a non-latch protection.
There is about 25ºC hysteresis. Once the
junction temperature drops to about 125ºC, it
initiates a soft startup.
N
Figure 6 —Power Off Sequence when VOUT >
2.5V
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
APPLICATION INFORMATION
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For applications that electrolytic capacitor or POS
capacitor with a controlled output of ESR is set
as output capacitors. The output voltage is set by
feedback resistors R1 and R2. As figure 8 shows.
in Figure 9. The VRAMP can be calculated as
shown in equation 6. R2 should be chosen
reasonably, a small R2 will lead to considerable
quiescent current loss while too large R2 makes
the FB noise sensitive. It is recommended to
choose a value within 5kΩ-100kΩ for R2, using a
comparatively larger R2 when VOUT is low, and a
smaller R2 when VOUT is high. And the value of
R1 then is determined as follow:
R
Setting the Output Voltage-Large ESR Caps
SW
L
Vo
FB
ESR
R1
R1
POSCAP
VOUT VFB( AVG)
R2
Figure8—Simplified Circuit of POS Capacitor
First, choose a value for R2. R2 should be
chosen reasonably, a small R2 will lead to
considerable quiescent current loss while too
large R2 makes the FB noise sensitive. It is
recommended to choose a value within 5kΩ100kΩ for R2, using a comparatively larger R2
when VOUT is low, and a smaller R2 when VOUT is
high. Then R1 is determined as follow with the
output ripple considered:
R1
VOUT
1
VOUT VREF
2
R2
VREF
(13)
VOUT is the output ripple determined by equation
21.
Setting the Output Voltage-Small ESR Caps
SW
FB
L
R4
Vo
C4
R9
R1
O
T
Ceramic
R2
Figure9—Simplified Circuit of Ceramic
Capacitor
When low ESR ceramic capacitor is used in the
output, an external voltage ramp should be
added to FB through resistor R4 and capacitor
C4.The output voltage is influenced by ramp
voltage VRAMP besides resistor divider as shown
N
R2
VFB( AVG)
R2
R 4 R9
(14)
The VFB(AVG) is the average value on the FB.
VFB(AVG) varies with the Vin, Vo, and load
condition, etc.. It is means the load regulation is
strictly related to the VFB(AVG). Also the line
regulation is related to the VFB(AVG) ,if one wants
to gets a better load or line regulation, a lower
VRAMP is suggested once it meets equation 8.
For PWM operation, VFB(AVG) value can be
deduced from equation 15.
VFB( AVG) VREF
R1 // R2
1
VRAMP
2
R1 // R2 R9
(15)
Usually, R9 is set to 0Ω, and it can also be set
following equation 16 for a better noise immunity.
It should be set to be 5 timers smaller than
R1//R2 to minimize its influence on Vramp.
R9
1 R1 R2
10 R1 R 2
(16)
Using equation 14 and 15 to calculate the output
voltage can be complicated. To simplify the
calculation of R1 in equation 14, a DC-blocking
capacitor Cdc can be added to filter the DC
influence from R4 and R9. Figure 9 shows a
simplified
circuit
with
external
ramp
compensation and a DC-blocking capacitor. With
this capacitor, R1 can easily be obtained by
using equation 17 for PWM mode operation.
R1
1
VRAMP
2
R2
1
VRAMP
2
VOUT VREF
VREF
(17)
Cdc is suggested to be at least 10 times larger
than C4 for better DC blocking performance, and
should be not larger than 0.47μF considering
startup performance. In case one wants to use
larger Cdc for a better FB noise immunity,
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MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
the
the
the
are
The input voltage ripple can be estimated as
follows:
VIN
IOUT
V
V
OUT (1 OUT )
fSW CIN VIN
VIN
The worst-case condition occurs at VIN = 2VOUT,
where:
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SW
Vo
L
R4
FB
C4
VIN
R1
Cdc
Ceramic
Input Capacitor
The input current to the step-down converter is
discontinuous. Therefore, a capacitor is required
to supply the AC current to the step-down
converter while maintaining the DC input voltage.
Ceramic capacitors are recommended for best
performance. In the layout, it’s recommended to
put the input capacitors as close to the IN pin as
possible.
The capacitance varies significantly over
temperature. Capacitors with X5R and X7R
ceramic dielectrics are recommended because
they are fairly stable over temperature.
The capacitors must also have a ripple current
rating greater than the maximum input ripple
current of the converter. The input ripple current
can be estimated as follows:
VOUT
V
(1 OUT )
VIN
VIN
(18)
O
T
The worst-case condition occurs at VIN = 2VOUT,
where:
IOUT
2
(19)
For simplification, choose the input capacitor
whose RMS current rating is greater than half of
the maximum load current.
The input capacitance value determines the input
voltage ripple of the converter. If there is input
voltage ripple requirement in the system design,
choose the input capacitor that meets the
specification
N
(21)
The output capacitor is required to maintain the
DC output voltage. Ceramic or POSCAP
capacitors are recommended. The output voltage
ripple can be estimated as:
Figure10—Simplified Circuit of Ceramic
Capacitor with DC blocking capacitor
ICIN
I
1
OUT
4 fSW CIN
Output Capacitor
R2
ICIN IOUT
(20)
R
combined with reduced R1 and R2 to limit
Cdc in a reasonable value without affecting
system start up. Be noted that even when
Cdc is applied, the load and line regulation
still Vramp related.
VOUT
VOUT
V
1
(1 OUT ) (RESR
) (22)
fSW L
VIN
8 fSW COUT
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 as:
VOUT
VOUT
V
(1 OUT )
VIN
8 fSW L COUT
2
(23)
The output voltage ripple caused by ESR is very
small. Therefore, an external ramp is needed to
stabilize the system. The external ramp can be
generated through resistor R4 and capacitor C4
following equation 4, 7 and 8.
In the case of POSCAP capacitors, the ESR
dominates the impedance at the switching
frequency. The ramp voltage generated from the
ESR is high enough to stabilize the system.
Therefore, an external ramp is not needed. A
minimum ESR value according to equation 3 is
required to ensure stable operation of the
converter. For simplification, the output ripple
can be approximated as:
VOUT
VOUT
V
(1 OUT ) RESR
fSW L
VIN
(24)
Inductor
The inductor is required to supply constant
current to the output load while being driven by
the switching input voltage. A larger value
inductor will result in less ripple current and lower
output ripple voltage. However, a larger value
MPQ8616 Rev. 1.2
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25
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
Where ∆IL is the peak-to-peak inductor ripple
current.
R
Choose an inductor that will not saturate under
the maximum inductor peak current. The peak
inductor current can be calculated as:
R
EC
N O
EW M
M
D E
ES N
D
IG E
N D
S F
O
inductor will have a larger physical size, higher
series resistance, and/or lower saturation current.
A good rule for determining the inductor value is
to allow the peak-to-peak ripple current in the
inductor to be approximately 10~30% of the
maximum output current. Also, make sure that
the peak inductor current is below the current
limit of the device. The inductance value can be
calculated as:
VOUT
V
L
(1 OUT )
fSW IL
VIN
(25)
ILP IOUT
VOUT
V
(1 OUT )
2 fSW L
VIN
(26)
The inductors listed in Table 1 are highly
recommended for the high efficiency they can
provide.
Table 1—Inductor Selection Guide
Part Number
Manufacturer
Inductance
(µH)
DCR
(mΩ)
Current
Rating (A)
Dimensions
L x W x H (mm3)
FDU1250C-R50M
FDU1250C-R56M
FDU1250C-R75M
FDU1250C-1R0M
TOKO
TOKO
TOKO
TOKO
0.50
0.56
0.75
1.0
1.3
1.6
1.7
2.2
46.3
42.6
32.7
31.3
13.3 x 12.1 x5
13.3 x 12.1 x5
13.3 x 12.1 x5
13.3 x 12.1 x5
Typical Design Parameter Tables
The following tables include recommended
component values for typical output voltages
(1.0V, 1.2V, 1.8V, 3.3V) and switching
frequencies (600kHz, 800kHz, and 1MHz). Refer
to Tables 2-4 for design cases without external
ramp compensation and Tables 5-6 for design
cases with external ramp compensation.
External ramp is not needed when high-ESR
capacitors, such as electrolytic or POSCAPs are
used. External ramp is needed when low-ESR
capacitors, such as ceramic capacitors are used.
For cases not listed in this datasheet, a calculator
in excel spreadsheet can also be requested
through a local sales representative to assist with
the calculation.
Table 2—COUT-Poscap, 600kHz, 5VIN
L
(μH)
1.0
1.0
R1
(kΩ)
19.8
29.4
R2
(kΩ)
30
30
R7
(kΩ)
300
365
1.5
1.0
29.4
20
453
1.8
1.0
39.2
20
549
3.3
1.0
44.2
10
1000
N
O
T
VOUT
(V)
1.0
1.2
Switching
Frequency
(kHz)
1000
800-1000
600-800
600
Table 3—COUT-Poscap, 800kHz, 5VIN
VOUT
(V)
1.0
L
(μH)
0.75
R1
(kΩ)
20
R2
(kΩ)
30
R7
(kΩ)
210
1.2
0.75
20
20
270
1.5
0.75
30
20
330
1.8
3.3
0.75
0.75
39
44.2
20
10
499
750
Table 5—COUT-Ceramic, 600kHz, 5VIN
VOUT
(V)
1.0
1.2
1.5
1.8
3.3
L
(μH)
1.0
1.0
1.0
1.0
1.0
R1
(kΩ)
21
33
51
45
62
R2
(kΩ)
30
30
30
20
10
R4
(kΩ)
240
220
330
270
160
C4
(pF)
470
470
390
470
680
R7
(kΩ)
309
365
464
549
953
Table 6—COUT-Ceramic, 800kHz, 5VIN
VOUT
(V)
1.0
1.2
1.5
1.8
3.3
L
(μH)
0.75
0.75
0.75
0.75
0.75
R1
(kΩ)
21
34
34
47.5
57.6
R2
(kΩ)
30
30
20
20
10
R4
(kΩ)
200
200
220
225
200
MPQ8616 Rev. 1.2
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C4
(pF)
470
470
470
470
560
R7
(kΩ)
226
270
324
402
750
26
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL APPLICATION
C1A
C1B
C1C
C1D
22uF
22uF
22uF
0.1uF 22uF
R7
C1E
R6
R8
100K
FREQ
C7
10pF
0
C3
1uF
L1
1uH
SW
VOUT
R1
+
C2A
220uF/20m
C2B
0.1uF
R
EC
N O
EW M
M
D E
ES N
D
IG E
N D
S F
O
10
360K
R3
BST
IN
R
VIN
MPQ8616
29.4K
EN
FB
VCC
C5
R2
R5
SS
4.7uF 100K
30K
C6
33nF
PG
PGND
AGND
Figure 13 — Typical Application Circuit with No External Ramp
MPQ8616, VIN=5V, VOUT=1.2V, IOUT=6/12A, fSW=600kHz
VIN
C1A
C1B
C1C
C1D
22uF
22uF
22uF
0.1uF 22uF
C1E
R7
R6
100K
R8
10
360K
C7
10pF
BST
IN
R3
0
C3
1uF
L1
1uH
SW
FREQ
VOUT
C4
R4
MPQ8616
220K
470pF
R9
0
EN
FB
VCC
C5
R5
R1
33K
C2A
C2B
C3C
22uF
22uF
22uF 22uF
C2D
C2E
0.1uF
R2
30K
SS
4.7uF 100K
C6
33nF
PG
PGND
AGND
Figure 14 — Typical Application Circuit with Low ESR Ceramic Capacitor
MPQ8616, VIN=5V, VOUT=1.2V, IOUT=6/12A, fSW=600kHz
VIN
C1A
C1B
C1C
C1D
22uF
22uF
22uF
0.1uF 22uF
C1E
R7
R6
100K
R8
10
360K
C7
10pF
BST
IN
R3
0
C3
1uF
L1
1uH
SW
FREQ
VOUT
R4
200K
EN
MPQ 8616
FB
VCC
C5
T
C2A
C2B
C3C
22uF
22uF
22uF 22uF
C2D
C2E
0.1uF
SS
C6
33nF
PG
O
560pF
Cdc
10nF
R1
29.1K
R2
R5
4.7uF 100K
N
C4
PGND
30K
AGND
Figure 15 — Typical Application Circuit with Low ESR Ceramic Capacitor
and DC-Blocking Capacitor.
MPQ8616, VIN=5V, VOUT=1.2V, IOUT=6/12A, fSW=600kHz
MPQ8616 Rev. 1.2
www.MonolithicPower.com
1/9/2019
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2019 MPS. All Rights Reserved.
27
MPQ8616, 6A/12A, 6V, SYNCHRONOUS STEP-DOWN CONVERTER
Schematic for PCB Layout Guide Line
Figure 16—PCB LAYOUT
VIN
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