EVALUATION KIT AVAILABLE
MAX5033
500mA, 76V, High-Efficiency, MAXPower
Step-Down DC-DC Converter
Features
General Description
The MAX5033 easy-to-use, high-efficiency, high-voltage,
step-down DC-DC converter operates from an input volt-
age up to 76V and consumes only 270μA quiescent cur-
rent at no load. This pulse-width modulated (PWM) con-
verter operates at a fixed 125kHz switching frequency at
heavy loads, and automatically switches to pulseskipping
mode to provide low quiescent current and high efficiency
at light loads. The MAX5033 includes internal frequency
compensation simplifying circuit implementation. The
device uses an internal low-onresistance, high-voltage,
DMOS transistor to obtain high efficiency and reduce
overall system cost. This device includes undervoltage
lockout, cycle-by-cycle current limit, hiccup-mode output
short-circuit protection, and thermal shutdown.
The MAX5033 delivers up to 500mA output current. The
output current may be limited by the maximum power
dissipation capability of the package. External shutdown
is included, featuring 10μA (typ) shutdown current. The
MAX5033A/B/C versions have fixed output voltages of
3.3V, 5V, and 12V, respectively, while the MAX5033D fea-
tures an adjustable output voltage, from 1.25V to 13.2V.
The MAX5033 is available in space-saving 8-pin SO and
8-pin plastic DIP packages and operates over the auto-
motive (-40°C to +125°C) temperature range.
● Wide 7.5V to 76V Input Voltage Range
● Fixed (3.3V, 5V, 12V) and Adjustable (1.25V to
13.2V) Voltage Versions
● 500mA Output Current
● Efficiency Up to 94%
● Internal 0.4Ω High-Side DMOS FET
● 270μA Quiescent Current at No Load, 10μA
Shutdown Current
● Internal Frequency Compensation
● Fixed 125kHz Switching Frequency
● Thermal Shutdown and Short-Circuit Current Limit
● 8-Pin SO and PDIP Packages
Ordering Information
PART
MAX5033AUSA
MAX5033AUPA
MAX5033AASA
MAX5033BUSA
MAX5033BUPA
MAX5033BASA
MAX5033CUSA
MAX5033CUPA
MAX5033CASA
MAX5033DUSA
MAX5033DUPA
MAX5033DASA
TEMP RANGE
0°C to +85°C
0°C to +85°C
0°C to +85°C
0°C to +85°C
0°C to +85°C
0°C to +85°C
0°C to +85°C
0°C to +85°C
PIN-
PACKAGE
8 SO
8 PDIP
8 SO
8 PDIP
8 SO
8 PDIP
8 SO
8 PDIP
ADJ
12
5.0
3.3
OUTPUT
VOLTAGE (V)
-40°C to +125°C 8 SO
Applications
● Consumer Electronics
● Industrial
● Distributed Power
-40°C to +125°C 8 SO
-40°C to +125°C 8 SO
Typical Application Circuit
V
IN
7.5V TO 76V
47µF
V
IN
BST
0.1µF
220µH
LX
ON/OFF
ON
OFF
R2
SGND
GND
FB
VD
0.1µF
D1
50SQ100
V
OUT
5V, 0.5A
33µF
-40°C to +125°C 8 SO
MAX5033
R1
This product is available in both leaded(Pb) and lead(Pb)-free
packages. To order the lead(Pb)-free package, add a + after
the part number.
Pin Configuration
BST
VD
SGND
FB
1
2
3
4
8
LX
V
IN
GND
ON/OFF
MAX5033
7
6
5
SO/PDIP
19-2979; Rev 5; 4/14
MAX5033
500mA, 76V, High-Efficiency, MAXPower
Step-Down DC-DC Converter
Absolute Maximum Ratings
(Voltages referenced to GND, unless otherwise specified.)
V
IN
.........................................................................-0.3V to +80V
SGND ....................................................................-0.3V to +0.3V
LX.................................................................-0.8V to (V
IN
+ 0.3V)
BST...............................................................-0.3V to (V
IN
+ 10V)
BST (transient < 100ns)................................-0.3V to (V
IN
+ 15V)
BST to LX................................................................-0.3V to +10V
BST to LX (transient < 100ns) ................................-0.3V to +15V
ON/OFF ..................................................................-0.3V to +80V
VD...........................................................................-0.3V to +12V
FB
MAX5033A/MAX5033B/MAX5033C...................-0.3V to +15V
MAX5033D.........................................................-0.3V to +12V
V
OUT
Short-Circuit Duration (V
IN
≤ 40V).....................Indefinite
VD Short-Circuit Duration..............................................Indefinite
Continuous Power Dissipation (T
A
= +70°C)
8-Pin PDIP (derate 9.1mW/°C above +70°C)..............727mW
8-Pin SO (derate 5.9mW/°C above +70°C)..................471mW
Operating Temperature Range
MAX5033_U_ _...................................................0°C to +85°C
MAX5033_A_ _..............................................-40°C to +125°C
Storage Temperature Range.............................-65°C to +150°C
Junction Temperature.......................................................+150°C
Lead Temperature (soldering, 10s)...................................+300°C
Soldering Temperature (reflow)
SO, PDIP Lead(Pb)-free...............................................+260°C
SO, PDIP Containing lead (Pb)....................................+240°C
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.
Electrical Characteristics (MAX5033_U_ _)
(V
IN
= +12V, V
ON/OFF
= +12V, I
OUT
= 0,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C. See the
Typical Operating Circuit.)
PARAMETER
SYMBOL
MAX5033A
Input Voltage Range
V
IN
MAX5033B
MAX5033C
MAX5033D
Undervoltage Lockout
UVLO
MAX5033A, V
IN
= 7.5V to 76V,
I
OUT
= 20mA to 500mA
Output Voltage
V
OUT
MAX5033B, V
IN
= 7.5V to 76V,
I
OUT
= 20mA to 500mA
MAX5033C, V
IN
= 15V to 76V,
I
OUT
= 20mA to 500mA
Feedback Voltage
V
FB
V
IN
= 7.5V to 76V, MAX5033D
V
IN
= 12V, I
LOAD
= 500mA, MAX5033A
Efficiency
η
V
IN
= 12V, I
LOAD
= 500mA, MAX5033B
V
IN
= 24V, I
LOAD
= 500mA, MAX5033C
V
IN
= 12V, V
OUT
= 5V, I
LOAD
= 500mA,
MAX5033D
V
FB
= 3.5V, V
IN
= 7.5V to 76V, MAX5033A
Quiescent Supply Current
I
Q
V
FB
= 5.5V, V
IN
= 7.5V to 76V, MAX5033B
V
FB
= 13V, V
IN
= 15V to 76V, MAX5033C
V
FB
= 1.3V, MAX5033D
Shutdown Current
Peak Switch Current Limit
Switch Leakage Current
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CONDITIONS
MIN
7.5
7.5
15
7.5
TYP
MAX
76.0
76.0
76
76.0
UNITS
V
5.2
3.185
4.85
11.64
1.192
3.3
5.0
12
1.221
86
90
94
90
270
270
270
270
10
0.95
1.5
1
440
440
440
440
45
2.1
3.415
5.15
12.36
1.250
V
V
V
%
µA
I
SHDN
I
LIM
I
OL
V
ON/OFF
= 0V, V
IN
= 7.5V to 76V
(Note 1)
V
IN
= 76V, V
ON/OFF
= 0V, V
LX
= 0V
µA
A
µA
Maxim Integrated │ 2
MAX5033
500mA, 76V, High-Efficiency, MAXPower
Step-Down DC-DC Converter
Electrical Characteristics (MAX5033_U_ _) (continued)
(V
IN
= +12V, V
ON/OFF
= +12V, I
OUT
= 0,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C. See the
Typical Operating Circuit.)
PARAMETER
Switch On-Resistance
PFM Threshold
FB Input Bias Current
ON/OFF CONTROL INPUT
ON/OFF Input-Voltage Threshold
ON/OFF Input-Voltage Hysteresis
ON/OFF Input Current
ON/OFF Operating Voltage Range
OSCILLATOR
Oscillator Frequency
Maximum Duty Cycle
VOLTAGE REGULATOR
Regulator Output Voltage
Dropout Voltage
Load Regulation
Thermal Resistance
(Junction to Ambient)
THERMAL SHUTDOWN
Thermal-Shutdown Junction
Temperature
Thermal-Shutdown Hysteresis
T
SH
T
HYST
+160
20
°C
°C
PACKAGE THERMAL CHARACTERISTICS
θ
JA
SO package (JEDEC 51)
DIP package (JEDEC 51)
170
110
°C/W
VD
V
IN
= 8.5V to 76V, I
L
= 0mA
7.5V ≤ V
IN
≤ 8.5V, I
L
= 1mA
ΔVD/ΔI
VD
0 to 5mA
6.9
7.8
2.0
150
8.8
V
V
Ω
f
OSC
D
MAX
MAX5033D
109
125
95
135
kHz
%
V
ON/OFF
V
HYST
I
ON/OFF
V
ON/OFF
V
ON/OFF
= 0V to V
IN
Rising trip point
1.53
1.69
100
10
150
76
1.85
V
mV
nA
V
SYMBOL
R
DS(ON)
I
PFM
I
B
CONDITIONS
I
SWITCH
= 500mA
Minimum switch current in any cycle
MAX5033D
35
-150
MIN
TYP
0.4
65
+0.01
MAX
0.80
95
+150
UNITS
Ω
mA
nA
Electrical Characteristics (MAX5033_A_ _)
(V
IN
= +12V, V
ON/OFF
= +12V, I
OUT
= 0,
T
A
= T
J
= -40°C to +125°C,
unless otherwise noted. Typical values are at T
A
= +25°C. See the
Typical Operating Circuit.)
(Note 2)
PARAMETER
SYMBOL
MAX5033A
Input Voltage Range
V
IN
MAX5033B
MAX5033C
MAX5033D
Undervoltage Lockout
UVLO
MAX5033A, V
IN
= 7.5V to 76V,
I
OUT
= 20mA to 500mA
Output Voltage
V
OUT
MAX5033B, V
IN
= 7.5V to 76V,
I
OUT
= 20mA to 500mA
MAX5033C, V
IN
= 15V to 76V,
I
OUT
= 20mA to 500mA
3.185
4.825
11.58
CONDITIONS
MIN
7.5
7.5
15
7.5
5.2
3.3
5.0
12
3.415
5.175
12.42
V
TYP
MAX
76.0
76.0
76
76.0
V
V
UNITS
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Maxim Integrated │ 3
MAX5033
500mA, 76V, High-Efficiency, MAXPower
Step-Down DC-DC Converter
Electrical Characteristics (MAX5033_A_ _) (continued)
(V
IN
= +12V, V
ON/OFF
= +12V, I
OUT
= 0,
T
A
= T
J
= -40°C to +125°C,
unless otherwise noted. Typical values are at T
A
= +25°C. See the
Typical Operating Circuit.)
(Note 2)
PARAMETER
Feedback Voltage
SYMBOL
V
FB
CONDITIONS
V
IN
= 7.5V to 76V, MAX5033D
V
IN
= 12V, I
LOAD
= 500mA, MAX5033A
Efficiency
η
V
IN
= 12V, I
LOAD
= 500mA, MAX5033B
V
IN
= 24V, I
LOAD
= 500mA, MAX5033C
V
IN
= 12V, V
OUT
= 5V, I
LOAD
= 500mA,
MAX5033D
V
FB
= 3.5V, V
IN
= 7.5V to 76V, MAX5033A
Quiescent Supply Current
I
Q
V
FB
= 5.5V, V
IN
= 7.5V to 76V, MAX5033B
V
FB
= 13V, V
IN
= 15V to 76V, MAX5033C
V
FB
= 1.3V, MAX5033D
Shutdown Current
Peak Switch Current Limit
Switch Leakage Current
Switch On-Resistance
PFM Threshold
FB Input Bias Current
ON/OFF CONTROL INPUT
ON/OFF Input-Voltage Threshold
ON/OFF Input-Voltage Hysteresis
ON/OFF Input Current
ON/OFF Operating Voltage Range
OSCILLATOR
Oscillator Frequency
Maximum Duty Cycle
VOLTAGE REGULATOR
Regulator Output Voltage
Dropout Voltage
Load Regulation
Thermal Resistance
(Junction to Ambient)
THERMAL SHUTDOWN
Thermal-Shutdown Junction
Temperature
Thermal-Shutdown Hysteresis
T
SH
T
HYST
+160
20
°C
°C
PACKAGE THERMAL CHARACTERISTICS
θ
JA
SO package (JEDEC 51)
DIP package (JEDEC 51)
170
110
°C/W
VD
V
IN
= 8.5V to 76V, I
L
= 0mA
7.5V ≤ V
IN
≤ 8.5V, I
L
= 1mA
ΔVD/ΔI
VD
0 to 5mA
6.5
7.8
2.0
150
9.0
V
V
Ω
f
OSC
D
MAX
MAX5033D
105
125
95
137
kHz
%
V
ON/OFF
V
HYST
I
ON/OFF
V
ON/OFF
V
ON/OFF
= 0V to V
IN
Rising trip point
1.50
1.69
100
10
150
76
1.85
V
mV
nA
V
I
SHDN
I
LIM
I
OL
R
DS(ON)
I
PFM
I
B
V
ON/OFF
= 0V, V
IN
= 7.5V to 76V
(Note 1)
V
IN
= 76V, V
ON/OFF
= 0V, V
LX
= 0V
I
SWITCH
= 500mA
Minimum switch current in any cycle
MAX5033D
35
-150
0.95
MIN
1.192
TYP
1.221
86
90
94
90
270
270
270
270
10
1.5
1
0.4
65
+0.01
0.80
110
+150
440
440
440
440
45
2.1
µA
A
µA
Ω
mA
nA
µA
%
MAX
1.250
UNITS
V
Note 1:
Switch current at which the current limit is activated.
Note 2:
All limits at -40°C are guaranteed by design, not production tested.
www.maximintegrated.com
Maxim Integrated │ 4
MAX5033
500mA, 76V, High-Efficiency, MAXPower
Step-Down DC-DC Converter
Typical Operating Characteristics
(V
IN
= 12V, V
ON/OFF
= 12V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at T
A
= +25°C. See the
Typical Operating
Circuit,
if applicable.)
V
OUT
vs. TEMPERATURE
(MAX5033CASA, V
OUT
= 12V)
MAX5033 toc01
MAX5033 toc02
12.3
12.2
V
OUT
(V)
12.1
12.0
11.9
11.8
5.05
V
OUT
(V)
I
OUT
= 0.1A
I
OUT
= 0.1A
12.3
12.2
V
OUT
(V)
I
OUT
= 0A
5.00
I
OUT
= 0.5A
12.1
12.0
I
OUT
= 0.5A
I
OUT
= 0.5A
4.95
11.9
4.90
11.8
-50 -25
0
25
50
75
100 125 150
-50
-25
0
TEMPERATURE (C)
50 75 100 125 150
TEMPERATURE (C)
25
10
20
30
40
50
60
70
80
INPUT VOLTAGE (V)
MAX5033 toc05
MAX5033 toc04
5.05
V
OUT
(V)
I
OUT
= 0A
12.3
12.2
V
OUT
(V)
V
IN
= 24V
5.05
V
OUT
(V)
V
IN
= 7.5V, 24V
5.00
I
OUT
= 0.5A
12.1
12.0
V
IN
= 76V
5.00
V
IN
= 76V
4.95
11.9
4.90
11.8
4.95
6
16
26
36
46
56
66
76
0
100
200
300
400
500
4.90
0
100
200
300
400
500
INPUT VOLTAGE (V)
I
LOAD
(mA)
I
LOAD
(mA)
MAX5033 toc07
MAX5033 toc08
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
0
100
200
300
400
V
IN
= 76V
V
IN
= 7.5V
V
IN
= 12V
V
IN
= 24V
V
IN
= 48V
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
V
IN
= 76V
V
IN
= 48V
V
IN
= 15V
V
IN
= 24V
OUTPUT CURRENT LIMIT (A)
1.7
1.4
1.1
0.8
0.5
MAX5033BASA
5% DROP IN V
OUT
-50 -25
0
25 50 75 100 125 150
TEMPERATURE (°C)
500
0
100
200
300
400
500
LOAD CURRENT (mA)
LOAD CURRENT (mA)
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Maxim Integrated │ 5
MAX5033 toc09
100
EFFICIENCY vs. LOAD CURRENT
(MAX5033BASA, V
OUT
= 5V)
100
EFFICIENCY vs. LOAD CURRENT
(MAX5033CASA, V
OUT
= 12V)
2.0
OUTPUT CURRENT LIMIT
vs. TEMPERATURE
MAX5033 toc06
5.10
LINE REGULATION
(MAX5033BASA, V
OUT
= 5V)
12.4
LOAD REGULATION
(MAX5033CASA, V
OUT
= 12V)
5.10
LOAD REGULATION
(MAX5033BASA, V
OUT
= 5V)
MAX5033 toc03
12.4
5.10
V
OUT
vs. TEMPERATURE
(MAX5033BASA, V
OUT
= 5V)
12.4
LINE REGULATION
(MAX5033CASA, V
OUT
= 12V)