MAX17502HAUD+ [MAXIM]
Switching Regulator, Current-mode, 1.9A, 640kHz Switching Freq-Max, BICMOS, PDSO14, 5 X 4.40 MM, ROHS COMPLIANT, TSSOP-14;
| 型号： | MAX17502HAUD+ |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Switching Regulator, Current-mode, 1.9A, 640kHz Switching Freq-Max, BICMOS, PDSO14, 5 X 4.40 MM, ROHS COMPLIANT, TSSOP-14 信息通信管理 开关 光电二极管 |
| 文件： | 总21页 (文件大小：2463K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
General Description
Benefits and Features
●ꢀ EliminatesꢀExternalꢀComponentsꢀandꢀReducesꢀTotalꢀ
Cost
The MAX17502 high-efficiency, high-voltage, synchronous
step-down DC-DC converter with integrated MOSFETs
operates over a 4.5V to 60V input voltage range. This
device is offered in a fixed 3.3V , 5V or adjustable output
• NoꢀSchottky-SynchronousꢀOperationꢀforꢀHighꢀ
EfficiencyꢀandꢀReducedꢀCost
• Internal Compensation and Feedback Divider for
3.3V and 5V Fixed Outputs
• All-Ceramic Capacitors, Ultra-Compact Layout
voltage (0.9V to 92%V ) while delivering up to 1A of
IN
current. The output voltage is accurate to within ±1.7%
over -40°C to +125°C. The MAX17502 is available in
compact TDFN and TSSOP packages. Simulation models
are available.
●ꢀ ReducesꢀNumberꢀofꢀDC-DCꢀRegulatorsꢀtoꢀStock
• Wideꢀ4.5Vꢀtoꢀ60VꢀInputꢀVoltageꢀRange
The device features peak-current-mode control with
pulse-width modulation (PWM) and operates with fixed
switching frequency at any load. The low-resistance,
on-chip MOSFETs ensure high efficiency at full load and
simplify the layout.
• 0.9V to 92%V Adjustable Output Voltage
• Delivers up to 1A
• 600kHzꢀandꢀ300kHzꢀSwitchingꢀFrequencyꢀOptions
• Available in a 10-Pin, 3mm x 2mm TDFN and
14-Pin, 5mm x 4.4mm TSSOP Packages
IN
A programmable soft-start feature allows users to reduce
input inrush current. The device also incorporates an
output enable/undervoltage lockout pin (EN/UVLO) that
allows the user to turn on the part at the desired input-
voltage level. An open-drain RESET pin provides a
delayed power-good signal to the system upon achieving
successful regulation of the output voltage.
●
ReducesꢀPowerꢀDissipation
• Peak Efficiency > 90%
• ShutdownꢀCurrentꢀ=ꢀ0.9μAꢀ(typ)
●ꢀ OperatesꢀReliablyꢀinꢀAdverseꢀIndustrialꢀEnvironmentsꢀ
• Hiccup-ModeꢀCurrentꢀLimit,ꢀSinkꢀCurrentꢀLimit,ꢀ
and Autoretry Startup
• Built-InꢀOutput-VoltageꢀMonitoringꢀ(Open-Drainꢀ
RESET Pin)
• Resistor-ProgrammableꢀEN/UVLOꢀThreshold
• Adjustable Soft-Start and Prebiased Power-Up
•ꢀ HighꢀIndustrialꢀ-40°Cꢀtoꢀ+125°CꢀAmbientꢀOperatingꢀ
TemperatureꢀRange/-40°Cꢀtoꢀ+150°CꢀJunctionꢀ
TemperatureꢀRange
Applications
●ꢀ IndustrialꢀProcessꢀControlꢀ
●ꢀ HVACꢀandꢀBuildingꢀControlꢀ
●ꢀ BaseꢀStation,ꢀVOIP,ꢀTelecomꢀ
●ꢀ HomeꢀTheatreꢀꢀ
ꢀ
●ꢀ Battery-PoweredꢀEquipment
●ꢀ General-PurposeꢀPoint-of-Load
Ordering Information/Selector Guide appears at end of data
sheet.
19-6245 Rev 5; 6/16
MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Absolute Maximum Ratings
V
ꢀtoꢀGND.............................................................-0.3Vꢀtoꢀ+70Vꢀ
Output Short-Circuit Duration.....................................Continuous
JunctionꢀTemperature......................................................+150°Cꢀ
StorageꢀTemperatureꢀRange.............................ꢀ-65°Cꢀtoꢀ+160°Cꢀ
Lead Temperature (soldering, 10s).................................+300°C
Soldering Temperature (reflow).......................................+260°C
IN
EN/UVLOꢀtoꢀGND.......................................-0.3V to (V + 0.3V)
LXꢀtoꢀPGND................................................-0.3V to (V + 0.3V)
IN
IN
FB,ꢀRESET,ꢀCOMP,ꢀSSꢀtoꢀGND .............................-0.3V to +6V
V
ꢀtoꢀGND..............................................................-0.3Vꢀtoꢀ+6Vꢀ
CC
GNDꢀtoꢀPGND.......................................................-0.3Vꢀtoꢀ+0.3Vꢀ
LXꢀTotalꢀRMSꢀCurrent.........................................................ꢀ±1.6Aꢀ
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability. Junction temperature greater than +125°C degrades operating lifetimes.
(Note 1)
Package Thermal Characteristics
10 TDFN
14 TSSOP
Continuous Power Dissipation (T = +70°C)
Continuous Power Dissipation (T = +70°C)
A
A
(derate 14.9mW/°C above +70°C) (multilayer board).1188.7mW
(derate 25.6mw/°C above +70°C) ..........................2051.3mW
Junction-to-AmbientꢀThermalꢀResistanceꢀ(θ ) ...........67.3°C/W
Junction-to-AmbientꢀThermalꢀResistanceꢀ(θ ) ..............39°C/W
JA
JA
Junction-to-CaseꢀThermalꢀResistanceꢀ(θ )................18.2°C/W
Junction-to-CaseꢀThermalꢀResistanceꢀ(θ ).....................3°C/W
JC
JC
Note 1:ꢀ PackageꢀthermalꢀresistancesꢀwereꢀobtainedꢀusingꢀtheꢀmethodꢀdescribedꢀinꢀJEDECꢀspecificationꢀJESD51-7,ꢀusingꢀaꢀfour-layerꢀ
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
Electrical Characteristics
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected. T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)ꢀ(Noteꢀ2)
PARAMETER
INPUT SUPPLY (V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
)
IN
InputꢀVoltageꢀRange
V
4.5
60
V
IN
I
V
= 0V, shutdown mode
0.9
4.75
2.5
3.5
µA
IN-SH
EN
Normal
switching mode,
no load
MAX17502E/F/G
MAX17502H
6.75
3.6
Input Supply Current
I
mA
IN-SW
ENABLE/UVLO (EN/UVLO)
V
V
V
V
V
rising
falling
1.194
1.114
1.218
1.135
0.7
1.236
1.156
ENR
EN
EN
EN
EN
EN Threshold
V
V
ENF
V
falling, true shutdown
= V = 60V, T = +25°C
EN-TRUESD
EN Input Leakage Current
I
8
200
nA
EN
IN
A
LDO
6V < V < 12V, 0mA < I
< 10mA,
IN
VCC
V
ꢀOutputꢀVoltageꢀRange
V
4.65
5
5.35
80
V
CC
CC
12V < V < 60V, 0mA < I
< 2mA
IN
VCC
V
V
Current Limit
Dropout
I
V
V
V
V
= 4.3V, V = 12V
15
40
mA
V
CC
VCC-MAX
CC
IN
V
= 4.5V, I = 5mA
VCC
4.1
CC
CC-DO
IN
V
rising
falling
3.85
3.55
4
4.15
3.85
CC-UVR
CC
CC
V
UVLO
V
CC
V
3.7
CC-UVF
Maxim Integrated
│ 2
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Electrical Characteristics (continued)
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected. T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)ꢀ(Noteꢀ2)
PARAMETER
POWER MOSFETs
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
T
T
= +25°C
0.55
0.85
1.2
A
I
= 0.5A
LX
High-SideꢀpMOSꢀOn-Resistance
R
Ω
= T = +125°C
DS-ONH
A
J
(sourcing)
(Note 3)
T
T
= +25°C
0.2
0.35
0.47
A
I
= 0.5A
LX
Low-SideꢀnMOSꢀOn-Resistance
R
Ω
= T = +125°C
DS-ONL
A
J
(sinking)
(Note 3)
V
V
= 0V, T = +25°C,
EN
LX
A
LX Leakage Current
I
1
µA
LX_LKG
= (V
+ 1V) to (V - 1V)
IN
PGND
SOFT-START (SS)
Charging Current
I
V
= 0.5V
4.7
5
5.3
µA
V
SS
SS
FEEDBACK (FB/VO)
FBꢀRegulationꢀVoltage
V
MAX17501G/H
0.884
6.8
0.9
12
0.916
17
FB_REG
MAX17502E, V
3.3V
=
FB
µA
nA
MAX17502F, V
= 5V
FB
FBꢀInputꢀBiasꢀCurrent
I
T
= +25NC
6.8
12
17
FB
A
MAX17502G/H,ꢀV
= 0.9V
FB
100
OUTPUT VOLTAGE (V
)
OUT
MAX17502E
MAX17502F
3.248
4.922
3.3
5
3.352
5.08
0.92 x
OutputꢀVoltageꢀRange
V
V
MAX17502G
MAX17502H
0.9
0.9
OUT
V
IN
0.965
x V
IN
TRANSCONDUCTANCE AMPLIFIER (COMP)
Transconductance
G
I
= ±2.5µA,ꢀMAX17502G/H
COMP
510
19
590
32
650
55
µS
µA
M
COMP Source Current
COMP Sink Current
I
MAX17502G/H
MAX17502G/H
MAX17502G/H
COMP_SRC
I
19
32
55
µA
COMP_SINK
Current-Sense Transresistance
R
0.45
0.5
0.55
V/A
CS
Maxim Integrated
│ 3
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Electrical Characteristics (continued)
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected. T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)ꢀ(Noteꢀ2)
PARAMETER
CURRENT LIMIT
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Peak Current-Limit Threshold
I
1.4
1.65
1.7
1.9
2
A
A
PEAK-LIMIT
I
RUNAWAY-
RunawayꢀCurrent-LimitꢀThreshold
1.45
LIMIT
Sink Current-Limit Threshold
I
MAX17502E/F/G/H
0.56
0.65
0.74
A
SINK-LIMIT
TIMINGS
MAX17502E/F/G
MAX17502H
560
280
280
600
300
300
640
320
320
V
> V
< V
FB
HICF
OUT-
Switching Frequency
f
kHz
SW
V
FB
OUT-HICF
EventsꢀtoꢀHiccupꢀafterꢀCrossingꢀ
RunawayꢀCurrentꢀLimit
1
Event
%
V
Undervoltage Trip Level to
OUT
V
V
> 0.95V (soft-start is done)
69.14
71.14
73.14
OUT-HICF
SS
CauseꢀHiccup
HICCUPꢀTimeout
Minimum On-Time
32,768
75
Cycles
ns
t
120
96
ON_MIN
MAX17502E/F/G
MAX17502H
92
94
V
V
= 0.98 x
FB
Maximum Duty Cycle
D
%
MAX
96.5
97.5
5
98.5
FB-REG
LX Dead Time
ns
RESET
0.02
0.45
V
I
= 1mA
RESET Output Level Low
RESET
RESET Output Leakage
CurrentꢀHigh
V
= 1.01 x V
, T = +25°C
µA
FB
FB-REG
A
V
V
V
V
falling
rising
90.5
93.5
92.5
95.5
94.5
97.5
%
%
V
V
Threshold for RESET Falling
OUT-OKF
FB
OUT
Threshold for RESETꢀRising
OUT-OKR
FB
OUT
RESETꢀDelayꢀAfterꢀFBꢀReachesꢀ
95%ꢀRegulation
V
rising
1024
Cycles
FB
THERMAL SHUTDOWN
Thermal-Shutdown Threshold
Thermal-ShutdownꢀHysteresis
Temperature rising
165
10
°C
°C
Note 2: All limits are 100% tested at +25°C. Limits over the operating temperature range and relevant supply voltage range are
guaranteedꢀbyꢀdesignꢀandꢀcharacterization.ꢀ
Note 3:ꢀ Guaranteedꢀbyꢀdesign,ꢀnotꢀproductionꢀtested.ꢀ
Maxim Integrated
│ 4
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Typical Operating Characteristics
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected, T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)
MAX17502E
MAX17502E
MAX17502F
LOAD AND LINE REGULATION,
3.3V OUTPUT, FIGURE 7 CIRCUIT
EFFICIENCY vs. LOAD CURRENT,
EFFICIENCY vs. LOAD CURRENT,
5V OUTPUT, FIGURE 8 CIRCUIT
3.3V OUTPUT, FIGURE 7 CIRCUIT
100
3.310
3.305
3.300
3.295
3.290
3.285
3.280
100
90
80
70
60
50
90
80
V
IN
= 12V
V = 36V
IN
V
IN
= 24V
V
= 36V
IN
V
IN
= 12V
V
IN
= 36V
V
IN
= 24V
V
IN
= 12V
70
60
V
IN
= 24V
V = 48V
IN
100 200 300 400 500 600 700 800 900 1000
LOAD CURRENT (mA)
0
100 200 300 400 500 600 700 800 900 1000
LOAD CURRENT (mA)
100 200 300 400 500 600 700 800 900 1000
LOAD CURRENT (mA)
MAX17502F
SHUTDOWN CURRENT
vs. TEMPERATURE
NO-LOAD SWITCHING CURRENT
vs. TEMPERATURE
LOAD AND LINE REGULATION,
5V OUTPUT, FIGURE 8 CIRCUIT
1.10
1.05
1.00
0.95
0.90
0.85
0.80
0.75
0.70
5.00
4.95
4.90
4.85
4.80
5.05
5.04
5.03
5.02
5.01
5.00
4.99
4.98
4.97
4.96
4.95
V
IN
= 12V
V = 36V
IN
V
= 24V
V = 48V
IN
IN
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
0
100 200 300 400 500 600 700 800 900 1000
LOAD CURRENT (mA)
OUTPUT VOLTAGE
OUTPUT VOLTAGE
EN/UVLO THRESHOLD
vs. TEMPERATURE
vs. TEMPERATURE (MAX17502F),
5V OUTPUT, FIGURE 8 CIRCUIT
vs. TEMPERATURE (MAX17502E),
3.3V OUTPUT, FIGURE 7 CIRCUIT
1.23
1.22
1.21
1.20
1.19
1.18
1.17
1.16
1.15
1.14
1.13
1.12
5.050
5.025
5.000
4.975
4.950
3.350
3.325
3.300
3.275
3.250
RISING
THRESHOLD
FALLING
THRESHOLD
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
Maxim Integrated
│ 5
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Typical Operating Characteristics (continued)
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected, T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)
FEEDBACK VOLTAGE
vs. TEMPERATURE
PEAK AND RUNAWAY CURRENT LIMIT
vs. TEMPERATURE
SWITCHING FREQUENCY
vs. TEMPERATURE
0.92
2.0
1.9
1.8
1.7
1.6
1.5
1.4
700
600
500
400
300
200
0.91
0.90
0.89
0.88
RUNAWAY
PEAK
CURRENT
CURRENT
LIMIT
LIMIT
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
-40 -20
0
20 40 60 80 100 120
TEMPERATURE (°C)
SOFT-START/SHUTDOWN FROM EN/UVLO
SOFT-START/SHUTDOWN FROM EN/UVLO
(MAX17502E), 3.3V OUTPUT, FIGURE 7 CIRCUIT
(MAX17502F), 5V OUTPUT, FIGURE 8 CIRCUIT
MAX17502 toc14
MAX17502 toc13
EN/UVLO
2V/div
EN/UVLO
2V/div
V
OUT
2V/div
V
OUT
1V/div
I
OUT
I
OUT
500mA/div
500mA/div
RESET
5V/div
RESET
2V/div
1ms/div
1ms/div
FULL-LOAD SOFT-START FROM VIN
FULL-LOAD SOFT-START FROM V
IN
(MAX17502E), 3.3V OUTPUT, FIGURE 7 CIRCUIT
(MAX17502F), 5V OUTPUT, FIGURE 8 CIRCUIT
MAX17502 toc15
MAX17502 toc16
V
V
IN
20V/div
IN
20V/div
I
OUT
I
OUT
500mA/div
500mA/div
V
V
OUT
OUT
1V/div
2V/div
RESET
5V/div
RESET
2V/div
400µs/div
400µs/div
Maxim Integrated
│ 6
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Typical Operating Characteristics (continued)
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected, T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)
SOFT-START WITH 2V PREBIAS
(MAX17502E), 3.3V OUTPUT, FIGURE 7 CIRCUIT
SOFT-START WITH 2.5V PREBIAS
(MAX17502F), 5V OUTPUT, FIGURE 8 CIRCUIT
MAX17502 toc17
MAX17502 toc18
EN/UVLO
2V/div
EN/UVLO
2V/div
V
OUT
V
OUT
1V/div
1V/div
RESET
2V/div
RESET
5V/div
400µs/div
400µs/div
LOAD TRANSIENT RESPONSE OF MAX17502F
LOAD TRANSIENT RESPONSE OF MAX17502E
(LOAD CURRENT STEPPED FROM NO-LOAD TO 500mA),
(LOAD CURRENT STEPPED FROM NO-LOAD TO 500mA),
5V OUTPUT, FIGURE 8 CIRCUIT
3.3V OUTPUT, FIGURE 7 CIRCUIT
MAX17502 toc19
MAX17502 toc20
V
(AC)
OUT
V
OUT
100mV/div
50mV/div
I
I
OUT
200mA/div
OUT
200mA/div
40µs/div
20µs/div
LOAD TRANSIENT RESPONSE OF MAX17502E
(LOAD CURRENT STEPPED FROM 500mA TO 1A),
LOAD TRANSIENT RESPONSE OF MAX17502F
(LOAD CURRENT STEPPED FROM 500mA TO 1A),
3.3V OUTPUT, FIGURE 7 CIRCUIT
5V OUTPUT, FIGURE 8 CIRCUIT
MAX17502 toc21
MAX17502 toc22
V
(AC)
V
OUT
100mV/div
OUT
50mV/div
I
OUT
I
OUT
500mA/div
500mA/div
20µs/div
20µs/div
Maxim Integrated
│ 7
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Typical Operating Characteristics (continued)
(V = 24V, V
= V
= 0V, C ꢀ=ꢀ2.2μF,ꢀC
ꢀ=ꢀ1μF,ꢀV
= 1.5V, C
= 3300pF, V = 0.98 x V
, LX = unconnected,
IN
GND
PGND
VIN
VCC
EN
SS
FB
OUT
RESET = unconnected, T = -40°C to +125°C, unless otherwise noted. Typical values are at T = +25°C. All voltages are referenced
A
A
toꢀGND,ꢀunlessꢀotherwiseꢀnoted.)
SWITCHING WAVEFORMS OF MAX17502F
AT 1A LOAD, 5V OUTPUT, FIGURE 8 CIRCUIT
OUTPUT OVERLOAD PROTECTION
OF MAX17502F, 5V OUTPUT, FIGURE 8 CIRCUIT
MAX17502 toc23
MAX17502 toc24
V
(AC)
OUT
50mV/div
I
V
LX
OUT
500mA/div
500mV/div
LX
20V/div
I
OUT
500mA/div
20ms/div
2µs/div
BODE PLOT OF MAX17502F
BODE PLOT OF MAX17502E
AT 1A LOAD, 5V OUTPUT, FIGURE 8 CIRCUIT
AT 1A LOAD, 3.3V OUTPUT, FIGURE 7 CIRCUIT
MAX17502 toc26
MAX17502 toc25
f
= 60.5kHz
CR
PM = 58°
f
= 55.2kHz
CR
PM = 53°
4
5
6
7 8 9 1
2
4
5
6
7 8 9 1
2
5V OUTPUT, 1A LOAD CURRENT,
FIGURE 8 CIRCUIT, CONDUCTED EMI CURVE
70
60
50
40
30
20
10
QUASI-PEAK LIMIT
AVERAGE LIMIT
PEAK
EMISSIONS
AVERAGE
EMISSIONS
30
1
10
0.15
FREQUENCY(MHz)
MEASUREDꢀON THEꢀMAX17502FTEVKITꢀWITHꢀINPUT FILTER—C = 2.2µF, L ꢀ=ꢀ10µH
IN IN
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Pin Configurations
TOP VIEW
TOP VIEW
MAX17502
+
PGND
N.C.
1
2
3
4
5
6
7
+
14 LX
PGND
1
2
10 LX
13 LX
V
IN
9
GND
V
IN
12 N.C.
11 GND
10 RESET
EN/UVLO
N.C.
MAX17502
EN/UVLO
3
4
5
8
7
6
RESET
N.C./COMP
SS
V
CC
V
CC
9
8
N.C./COMP
SS
EP*
FB/VO
EP*
FB/VO
TDFN
TSSOP
(5mm x 4.4mm)
(3mm x 2mm)
*EP = EXPOSED PAD. CONNECT TO GND
Pin Description
PIN
TSSOP
NAME
FUNCTION
TDFN
PowerꢀGround.ꢀConnectꢀPGNDꢀexternallyꢀtoꢀtheꢀpowerꢀgroundꢀplane.ꢀConnectꢀGNDꢀandꢀPGNDꢀ
pins together at the ground return path of the V bypass capacitor.
1
2
1
3
PGND
CC
V
Power-Supply Input. The input supply range is from 4.5V to 60V.
IN
Enable/Undervoltage Lockout Input. Drive EN/UVLO high to enable the output voltage. Connect
3
4
5
6
4
6
7
8
EN/UVLO
to the center of the resistive divider between V ꢀandꢀGNDꢀtoꢀsetꢀtheꢀinputꢀvoltageꢀ(undervoltageꢀ
IN
threshold) at which the device turns on. Pull up to V for always on.
IN
V
5VꢀLDOꢀOutput.ꢀBypassꢀV ꢀwithꢀ1µFꢀceramicꢀcapacitanceꢀtoꢀGND.ꢀ
CC
CC
FeedbackꢀInput.ꢀForꢀfixedꢀoutputꢀvoltageꢀdevices,ꢀdirectlyꢀconnectꢀFB/VOꢀtoꢀtheꢀoutput.ꢀForꢀ
adjustableꢀoutputꢀvoltageꢀdevices,ꢀconnectꢀFB/VOꢀtoꢀtheꢀcenterꢀofꢀtheꢀresistiveꢀdividerꢀbetweenꢀ
FB/VO
V
ꢀandꢀGND.
OUT
SS
Soft-StartꢀInput.ꢀConnectꢀaꢀcapacitorꢀfromꢀSSꢀtoꢀGNDꢀtoꢀsetꢀtheꢀsoft-startꢀtime.ꢀ
ExternalꢀLoopꢀCompensation.ꢀForꢀadjustableꢀoutputꢀvoltageꢀ(MAX17502G/H),ꢀconnectꢀtoꢀanꢀRCꢀ
networkꢀfromꢀCOMPꢀtoꢀGND.ꢀSeeꢀExternal Loop Compensation for Adjustable Output Versions
sectionꢀforꢀmoreꢀdetails.ꢀForꢀfixedꢀoutputꢀvoltageꢀ(MAX17502E/F),ꢀthisꢀpinꢀisꢀaꢀnoꢀconnectꢀ(N.C.)ꢀ
and should be left unconnected.
7
9
N.C./COMP
Open-Drain RESET Output. The RESETꢀoutputꢀisꢀdrivenꢀlowꢀifꢀFBꢀdropsꢀbelowꢀ92.5%ꢀofꢀitsꢀsetꢀ
value. RESETꢀgoesꢀhighꢀ1024ꢀclockꢀcyclesꢀafterꢀFBꢀrisesꢀaboveꢀ95.5%ꢀofꢀitsꢀsetꢀvalue.ꢀRESET
8
10
RESET
is valid when the device is enabled and V is above 4.5V.
IN
9
11
GND
AnalogꢀGround
Switching Node. Connect LX to the switching side of the inductor. LX is high impedance when
the device is in shutdown mode.
10
13, 14
LX
—
—
2, 5, 12
N.C.
EP
No Connection. Not internally connected.
ExposedꢀPad.ꢀConnectꢀtoꢀtheꢀGNDꢀpinꢀofꢀtheꢀIC.ꢀConnectꢀtoꢀaꢀlargeꢀcopperꢀplaneꢀbelowꢀtheꢀICꢀ
to improve heat dissipation capability.
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Block Diagram
V
CC
PGND
N DRIVER
5µA
SS
SS
LX
MAX17502
HICCUP
P DRIVER
V
IN
CURRENT
SENSE
V
CC
PWM
CLK
PWM
LOGIC
LDO
OSC
COMPARATOR
COMP
HICCUP
SLOPE
COMPENSATION
START
EN
FB
RESET
RESET
LOGIC
SS
900mV
REFERENCE
SWITCHOVER
LOGIC
COMP
N.C./COMP
G
M
INTERNAL
COMPENSATION
(FOR E, F VERSIONS)
GND
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Detailed Description
V
OUT
× t
ON(MIN)
V
=
IN(MAX)
The MAX17502 synchronous step-down regulator oper-
ates from 4.5V to 60V and delivers up to 1A load current.
Output voltage regulation accuracy meets ±1.7% over
temperature.
f
SW (MAX)
where V
is the steady-state output voltage, I
OUT(MAX)
OUT
isꢀtheꢀmaximumꢀloadꢀcurrent,ꢀR
is the DC resistance
DCR
of the inductor, f
is the switching frequency (max-
is the worst-case minimum switch
SW(MAX)
The device uses a peak-current-mode control scheme.
An internal transconductance error amplifier generates an
integrated error voltage. The error voltage sets the duty
cycle using a PWM comparator, a high-side current-sense
amplifier, and a slope-compensation generator. At each
rising edge of the clock, the high-side p-channel MOSFET
turns on and remains on until either the appropriate or
maximum duty cycle is reached, or the peak current limit
is detected.
imum) and t
ON(MIN)
on-time (120ns). The following table lists the f
SW(MAX)
and D
values to be used for calculation for different
MAX
versions of the MAX17502:
PART VERSION
MAX17502E/F/G
MAX17502H
f
(kHz)
D
MAX
SW (MAX)
640
0.92
320
0.965
During the high-side MOSFET’s on-time, the inductor
current ramps up. During the second half of the switching
cycle, the high-side MOSFET turns off and the low-side
n-channel MOSFET turns on and remains on until either
the next rising edge of the clock arrives or sink current
limit is detected. The inductor releases the stored energy
as its current ramps down, and provides current to the
Overcurrent Protection/HICCUP Mode
The device is provided with a robust overcurrent-protec-
tion scheme that protects the device under overload and
output short-circuit conditions. A cycle-by-cycle peak cur-
rent limit turns off the high-side MOSFET whenever the
high-side switch current exceeds an internal limit of 1.65A
(typ). A runaway current limit on the high-side switch cur-
rent at 1.7A (typ) protects the device under high input volt-
age, short-circuit conditions when there is insufficient out-
put voltage available to restore the inductor current that
built up during the on period of the step-down converter.
One occurrence of the runaway current limit triggers a
hiccup mode. In addition, if due to a fault condition, output
voltage drops to 71.14% (typ) of its nominal value any
time after soft-start is complete, hiccup mode is triggered.
outputꢀ (theꢀ internalꢀ lowꢀ R
pMOS/nMOS switches
DSON
ensure high efficiency at full load).
This device also integrates enable/undervoltage lockout
(EN/UVLO), adjustable soft-start time (SS), and open-
drain reset output (RESET) functionality.
Linear Regulator (V
)
CC
An internal linear regulator (V ) provides a 5V nominal
CC
supply to power the internal blocks and the low-side
MOSFET driver. The output of the V
linear regulator
CC
shouldꢀ beꢀ bypassedꢀ withꢀ aꢀ 1μFꢀ ceramicꢀ capacitorꢀ toꢀ
GND.ꢀTheꢀdeviceꢀemploysꢀanꢀundervoltage-lockoutꢀcircuitꢀ
In hiccup mode, the converter is protected by suspend-
ing switching for a hiccup timeout period of 32,768 clock
cycles. Once the hiccup timeout period expires, soft-start
is attempted again. This operation results in minimal
power dissipation under overload fault conditions.
that disables the internal linear regulator when V
falls
CC
below 3.7V (typical). The internal V
linear regulator can
CC
source up to 40mA (typical) to supply the device and to
power the low-side gate driver.
RESET Output
Operating Input Voltage Range
The device includes a RESET comparator to monitor the
output voltage. The open-drain RESET output requires
an external pullup resistor. RESET can sink 2mA of cur-
rent while low. RESET goes high (high impedance) 1024
switching cycles after the regulator output increases
above 95.5% of the designated nominal regulated volt-
age. RESET goes low when the regulator output voltage
drops to below 92.5% of the nominal regulated voltage.
RESET also goes low during thermal shutdown. RESET
The maximum operating input voltage is determined by
the minimum controllable on-time and the minimum oper-
ating input voltage is determined by the maximum duty
cycle and circuit voltage drops. The minimum and maxi-
mum operating input voltages for a given output voltage
should be calculated as:
V
+ (I
×(R
+ 0.47))
DCR
OUT
OUT(MAX)
V
=
IN(MIN)
D
MAX
is valid when the device is enabled and V is above 4.5V.
IN
+ (I
× 0.73)
OUT(MAX)
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Select a low-loss inductor closest to the calculated value
with acceptable dimensions and having the lowest pos-
Prebiased Output
When the device starts into a prebiased output, both the
high-side and low-side switches are turned off so the
converterꢀ doesꢀ notꢀ sinkꢀ currentꢀ fromꢀ theꢀ output.ꢀ High-
side and low-side switches do not start switching until
the PWM comparator commands the first PWM pulse, at
which point switching commences first with the high-side
switch. The output voltage is then smoothly ramped up to
the target value in alignment with the internal reference.
sible DC resistance. The saturation current rating (I
)
SAT
of the inductor must be high enough to ensure that satu-
ration can occur only above the peak current-limit value
(I
(typ) = 1.65A for the device).
PEAK-LIMIT
Output Capacitor Selection
X7Rꢀceramicꢀoutputꢀcapacitorsꢀareꢀpreferredꢀdueꢀtoꢀtheirꢀ
stability over temperature in industrial applications. The
outputꢀ capacitorꢀ isꢀ usuallyꢀ sizedꢀ toꢀ supportꢀ aꢀ stepꢀ loadꢀ
of 50% of the maximum output current in the application,
so the output-voltage deviation is contained to ±3% of the
output-voltage change.
Thermal-Overload Protection
Thermal-overload protection limits total power dissipation
in the device. When the junction temperature of the device
exceeds +165°C, an on-chip thermal sensor shuts down
the device, allowing the device to cool. The thermal sensor
turns the device on again after the junction temperature
cools by 10°C. Soft-start resets during thermal shutdown.
Carefully evaluate the total power dissipation (see the
Power Dissipation section) to avoid unwanted triggering of
the thermal-overload protection in normal operation.
For fixed 3.3V output voltage versions, connect a mini-
mumꢀ ofꢀ 22μFꢀ (1210)ꢀ capacitorꢀ atꢀ theꢀ output.ꢀ Forꢀ fixedꢀ
5Vꢀoutputꢀvoltageꢀversions,ꢀconnectꢀaꢀminimumꢀofꢀ10μFꢀ
(1210) capacitor at the output. For adjustable output volt-
age versions, the output capacitance can be calculated
as follows:
I
× t
RESPONSE
1
2
STEP
C
=
×
Applications Information
OUT
∆V
OUT
Input Capacitor Selection
0.33
1
The discontinuous input-current waveform of the buck
converter causes large ripple currents in the input capaci-
tor. The switching frequency, peak inductor current, and
the allowable peak-to-peak voltage ripple that reflects
back to the source dictate the capacitance requirement.
The device’s high switching frequency allows the use of
smallerꢀ valueꢀ inputꢀ capacitors.ꢀ X7Rꢀ capacitorsꢀ areꢀ rec-
ommended in industrial applications for their temperature
stability.ꢀAꢀminimumꢀvalueꢀofꢀ2.2μFꢀshouldꢀbeꢀusedꢀforꢀtheꢀ
inputꢀcapacitor.ꢀHigherꢀvaluesꢀhelpꢀreduceꢀtheꢀrippleꢀonꢀ
the input DC bus further. In applications where the source
is located distant from the device input, an electrolytic
capacitorꢀshouldꢀbeꢀaddedꢀinꢀparallelꢀtoꢀtheꢀ2.2μFꢀceramicꢀ
capacitor to provide necessary damping for potential
oscillations caused by the longer input power path and
input ceramic capacitor.
t
≅
+
RESPONSE
f
f
SW
C
where I
is the load current step, t
responseꢀ timeꢀ ofꢀ theꢀ controller,ꢀ ΔV
output-voltage deviation, f is the target closed-loop cross-
is the switching frequency. Select
f to be 1/12th of f . Consider DC bias and aging effects
while selecting the output capacitor.
is the
STEP
RESPONSE
is the allowable
OUT
C
over frequency, and f
SW
SW
C
Soft-Start Capacitor Selection
The MAX17502 implements adjustable soft-start operation
to reduce inrush current. A capacitor connected from the
SSꢀpinꢀtoꢀGNDꢀprogramsꢀtheꢀsoft-startꢀperiod.
The selected output capacitance (C
) and the output
SEL
voltage (V
) determine the minimum required soft-start
OUT
capacitor as follows:
Inductor Selection
-6
Three key inductor parameters must be specified for
operation with the device: inductance value (L), inductor
C
SS
x C
x V
SEL OUT
The soft-start time (t ) is related to the capacitor connected
at SS (C ) by the following equation:
SS
saturation current (I
),ꢀandꢀDCꢀresistanceꢀ(R
). The
SAT
DCR
SS
switching frequency, and output voltage determine the
inductor value as follows:
CSS
tSS
=
-6
5.55 x 10
2.4 x VOUT
L =
fSW
where V
and f
are nominal values.
OUT
SW
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Adjusting Output Voltage
External Loop Compensation for Adjustable
Output Versions
The MAX17502 uses peak current-mode control scheme
andꢀneedsꢀonlyꢀaꢀsimpleꢀRCꢀnetworkꢀtoꢀhaveꢀaꢀstable,ꢀ
high-bandwidth control loop for the adjustable output volt-
age versions. The basic regulator loop is modeled as a
power modulator, an output feedback divider, and an error
The MAX17502E and MAX17502F have preset output
voltagesꢀofꢀ3.3Vꢀandꢀ5.0V,ꢀrespectively.ꢀConnectꢀFB/VOꢀ
directly to the positive terminal of the output capacitor
(see the Typical Applications Circuits).
Theꢀ MAX17502G/Hꢀ offerꢀ anꢀ adjustableꢀ outputꢀ voltageꢀ
from 0.9V to 92%V . Set the output voltage with a resis-
IN
amplifier.ꢀTheꢀpowerꢀmodulatorꢀhasꢀDCꢀgainꢀG
,
MOD(dc)
tive voltage-divider connected from the positive terminal
withꢀaꢀpoleꢀandꢀzeroꢀpair.ꢀTheꢀfollowingꢀequationꢀdefinesꢀ
the power modulator DC gain:
of the output capacitor (V )ꢀ toꢀ GNDꢀ (seeꢀ Figure 1).
OUT
Connectꢀ theꢀ centerꢀ nodeꢀ ofꢀ theꢀ dividerꢀ toꢀ FB/VO.ꢀ Toꢀ
optimizeꢀefficiencyꢀandꢀoutputꢀaccuracy,ꢀuseꢀtheꢀfollowingꢀ
procedureꢀtoꢀchooseꢀtheꢀvaluesꢀofꢀR4ꢀandꢀR5:
2
G
=
MOD(dc)
1
0.4
0.5 -D
f ×L
SW
+
+
R
V
LOAD
IN
SEL
Forꢀ MAX17502G,ꢀ selectꢀ theꢀ parallelꢀ combinationꢀ ofꢀ R4ꢀ
andꢀR5,ꢀRpꢀtoꢀbeꢀlessꢀthanꢀ15kΩ.ꢀForꢀtheꢀMAX17502H,ꢀ
selectꢀtheꢀparallelꢀcombinationꢀofꢀR4ꢀandꢀR5,ꢀRpꢀtoꢀbeꢀ
lessꢀthanꢀ30kΩ.ꢀOnceꢀRpꢀisꢀselected,ꢀcalculateꢀR4ꢀas:
whereꢀ R
= V
/I
, f
is the switching
LOAD
OUT OUT(MAX) SW
frequency, L
is the selected output inductance, D is
SEL
the duty ratio, D = V V .
OUT/ IN
The compensation network is shown in Figure 3.
Rp × V
OUT
R4 =
R can be calculated as:
Z
0.9
CalculateꢀR5ꢀasꢀfollows:
R
= 6000 × f × C
× V
SEL OUT
Z
C
R4 × 0.9
whereꢀR ꢀisꢀinꢀΩ.ꢀChooseꢀf to be 1/12th of the switching
frequency.
Z
C
R5 =
(V
- 0.9)
OUT
C can be calculated as follows:
Z
C
×G
MOD(dc)
SEL
Setting the Input Undervoltage Lockout Level
C =
Z
2ꢀxꢀR
The device offers an adjustable input undervoltage-
lockout level. Set the voltage at which the device turns
Z
C can be calculated as follows:
P
on with a resistive voltage-divider connected from V
IN
toꢀGNDꢀ(seeꢀFigure 2). Connect the center node of the
1
C
=
P
divider to EN/UVLO.
π×R × f
Z
SW
ChooseꢀR1ꢀtoꢀbeꢀ3.3MΩ,ꢀandꢀthenꢀcalculateꢀR2ꢀas:
R1×1.218
R2 =
V
IN
(V
-1.218)
INU
R1
where V
is the voltage at which the device is required
INU
EN/UVLO
to turn on. For adjustable output voltage devices, ensure
that V
is higher than 0.8 x V
.
INU
OUT
R2
GND
V
OUT
Figure 2. Adjustable EN/UVLO Network
R4
TO COMP PIN
FB/VO
R5
R
Z
GND
C
P
C
Z
Figure 1. Setting the Output Voltage
Figure 3. External Compensation Network
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Power Dissipation
PCB Layout Guidelines
At a particular operating condition, the power losses that
lead to temperature rise of the device are estimated as
follows:
CarefulꢀPCBꢀlayoutꢀisꢀcriticalꢀtoꢀachieveꢀlowꢀswitchingꢀloss-
es and stable operation. For a sample layout that ensures
first-pass success, refer to the MAX17502 evaluation kit
layouts available at www.maximintegrated.com. Follow
theseꢀguidelinesꢀforꢀgoodꢀPCBꢀlayout:
1
2
P
= (P
×( - 1)) - I
×R
OUT DCR
)
LOSS
(
OUT
η
1) All connections carrying pulsed currents must be very
short and as wide as possible. The loop area of these
connections must be made very small to reduce stray
inductance and radiated EMI.
P
= V
×I
OUT
OUT OUT
where P
ꢀisꢀtheꢀoutputꢀpower,ꢀηꢀisꢀisꢀtheꢀefficiencyꢀofꢀ
OUT
theꢀdevice,ꢀandꢀR
is the DC resistance of the output
2) A ceramic input filter capacitor should be placed close
DCR
inductor (refer to the Typical Operating Characteristics
in the evaluation kit data sheets for more information on
efficiency at typical operating conditions).
to the V pin of the device. The bypass capacitor for
IN
the V
pin should also be placed close to the V
CC
CC
pin. External compensation components should be
placed close to the IC and far from the inductor. The
feedback trace should be routed as far as possible
from the inductor.
For a typical multilayer board, the thermal performance
metrics for the 10-pin TDFN package are given as:
θ
= 67.3°C W
JA
JC
3) The analog small-signal ground and the power ground
for switching currents must be kept separate. They
should be connected together at a point where switch-
ing activity is at minimum, typically the return terminal
θ
= 18.2°C W
For a typical multilayer board, the thermal performance
metrics for the 14-pin TSSOP package are given as:
of the V
bypass capacitor. The ground plane should
CC
be kept continuous as much as possible.
θ
= 39°C W
JA
4) A number of thermal throughputs that connect to a
large ground plane should be provided under the
exposed pad of the device, for efficient heat dissipation.
θ
= 3°C W
JC
The junction temperature of the device can be estimated
Figure 4, 5, and 6 show the recommended component
placement for MAX17502 in TDFN and TSSOP packages.
at any given maximum ambient temperature (T
from the following equation:
)
A_MAX
T
= T
+ θ ×P
A_MAX JA LOSS
(
)
J_MAX
If the application has a thermal-management system that
ensures that the exposed pad of the device is maintained
at a given temperature (T ) by using proper heat
EP_MAX
sinks, then the junction temperature of the device can be
estimated at any given maximum ambient temperature as:
T
= T
+ θ ×P
(
)
J_MAX
EP_MAX JC LOSS
Junctionꢀ temperatureꢀ greaterꢀ thanꢀ +125°Cꢀ degradesꢀ
operating lifetimes.
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
V
PLANE
PGND PLANE
OUT
C4
L1
C1
LX PLANE
EP
V
IN
PLANE
R1
R2
RESET
C2
R4
C3
GND PLANE
VIAS TO BOTTOM SIDE PGND PLANE
VIAS TO BOTTOM SIDE V TRACK
OUT
VIAS TO BOTTOM SIDE GND PLANE
Figure 4. Recommended Component Placement for MAX17502E/F
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
V
PLANE
PGND PLANE
OUT
C4
L1
C1
LX PLANE
RESET
EP
V
IN
PLANE
R1
R2
R3
C2
R4
C3
C9
C5
R5
GND PLANE
VIAS TO BOTTOM SIDE PGND PLANE
VIAS TO BOTTOM SIDE V TRACK
OUT
VIAS TO BOTTOM SIDE GND PLANE
Figure 5. Recommended Component Placement for MAX17502G
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
V
OUT
PLANE
PGND PLANE
C4
L1
C1
R1
LX PLANE
V
IN
PLANE
EP
R2
RESET
R3
C2
R4
C3
C9
C5
R5
GND PLANE
VIAS TO BOTTOM SIDE PGND PLANE
VIAS TO BOTTOM SIDE V TRACK
OUT
VIAS TO BOTTOM SIDE GND PLANE
Figure 6. Recommended Component Placement for MAX17502H
Maxim Integrated
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Typical Applications Circuits
L1
15µH
V
V
OUT
IN
V
LX
IN
3.3V, 1A
24V
C1
C4
R1
2.2µF
22µF
3.32MΩ
1210
1210
1
JU1 2
3
PGND
EN/UVLO
R2
866kΩ
MAX17502E
GND
V
CC
C2
1µF
FB/VO
SS
C3
3300pF
L1 = LPS6235-153
RESET
N.C.
RESET
Figure 7. MAX17502E Application Circuit (3.3V Output, 1A Maximum Load Current, 600kHz Switching Frequency)
L1
22µH
V
V
OUT
IN
V
LX
IN
5V, 1A
24V
C1
2.2µF
1210
C4
10µF
1210
R1
3.32MΩ
1
JU1 2
3
PGND
EN/UVLO
R2
866kΩ
MAX17502F
GND
V
CC
C2
1µF
FB/VO
SS
C3
3300pF
L1 = LPS6235-223
N.C.
RESET
RESET
Figure 8. MAX17502F Application Circuit (5V Output, 1A Maximum Load Current, 600kHz Switching Frequency)
Maxim Integrated
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
L1
47µH
V
V
OUT
IN
V
LX
IN
12V, 1A
24V
C1
2.2µF
1210
C4
R1
10µF
3.32MΩ
1210
1
JU1 2
3
PGND
EN/UVLO
R2
316kΩ
R4
174kΩ
MAX17502G
GND
V
CC
C2
1µF
FB/VO
SS
C3
6800pF
R5
14kΩ
COMP
RESET
RESET
R3
C9
12pF
20kΩ
L1 = MSS1038-473
C5
2200pF
Figure 9. MAX17502G Application Circuit (12V Output, 1A Maximum Load Current, 600kHz Switching Frequency)
L1
22µH
V
V
OUT
2.5V, 1A
IN
V
LX
IN
24V
C1
2.2µF
1210
C4
47µF,
1210
R1
3.32MΩ
1
JU1 2
3
PGND
EN/UVLO
R2
1MΩ
R4
MAX17502H
69.8kΩ
GND
V
CC
C2
1µF
FB/VO
SS
C3
6800pF
R5
39.2kΩ
COMP
RESET
RESET
R3
C9
47pF
16.9kΩ
L1 = LPS6235-223
C5
3300pF
Figure 10. MAX17502H Application Circuit (2.5V Output, 1A Maximum Load Current, 300kHz Switching Frequency)
Maxim Integrated
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Ordering Information/Selector Guide
SWITCHING
FREQUENCY (kHz)
PART
PIN-PACKAGE
OUTPUT VOLTAGE (V)
MODE
MAX17502EATB+
MAX17502FATB+
MAX17502GATB+
MAX17502HAUD+
10 TDFN-EP*
10 TDFN-EP*
10 TDFN-EP*
14 TSSOP-EP*
3.3
5
600
600
600
300
PWM
PWM
PWM
PWM
Adjustable
Adjustable
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Chip Information
PROCESS:ꢀBiCMOS
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.com/packages. Note
thatꢀaꢀ“+”,ꢀ“#”,ꢀorꢀ“-”ꢀinꢀtheꢀpackageꢀcodeꢀindicatesꢀRoHSꢀstatusꢀ
only. Package drawings may show a different suffix character, but
theꢀdrawingꢀpertainsꢀtoꢀtheꢀpackageꢀregardlessꢀofꢀRoHSꢀstatus.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE LAND PATTERN
NO.
NO.
10 TDFN
T1032N+1
U14E+3
21-0429
21-0108
90-0082
90-0119
14 TSSOP
Maxim Integrated
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MAX17502
60V, 1A, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converter
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
1
5/12
Initial release
—
11/12
AddedꢀMAX17502GꢀandꢀMAX17502Hꢀtoꢀdataꢀsheet
1–17
Added dotted line for exposed pad in Pin Configuration, and added
explanation on detailed condition for RESET
2
3
1/13
8/14
9, 11
Updated General Description, Benefits and Features, Pin Description, and
Adjusting Output Voltage sections.
1, 9, 13
4
5
6/15
6/16
Added output voltage to TOC captions
8–12, 16–18, 22, 23
1–8, 14, 19
Updated operating and junction temperature values
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
©
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
2016 Maxim Integrated Products, Inc.
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