ETC MAX15062

19-6685; Rev 1; 10/13
备有评估板
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
概述
优势和特性
MAX15062高 效、 高 压、 同 步 降 压 型DC-DC转 换 器 内 置
MOSFET，工作在4.5V至60V输入电压范围。转换器提供
高达300mA的输出电流，输出电压为3.3V (MAX15062A)、 5V (MAX15062B)和可调输出电压(MAX15062C)。器件工 作 在-40°C至+125°C温 度 范 围， 采 用 紧 凑 的8引 脚(2mm x 2mm) TDFN封装。提供仿真模式。
●
器件采用峰值电流模式架构，带有MODE引脚，可用于在
脉宽调制(PWM)或脉冲频率调制(PFM)模式下控制器件工
作。PWM工作模式在任何负载条件下都保持固定频率工
作，在对开关频率变化敏感的应用中非常有用。PFM工作
模式消除了负向电感电流以及轻载条件下额外的跳脉冲，
以提高效率。低导通电阻片上MOSFET确保满载时保持高
效，同时也简化了PCB布局。
● 缩减DC-DC稳压器库存清单
• 4.5V至60V宽输入电压范围
• 3.3V和5V固定输出电压
• 可调0.9V至0.89 × VIN输出电压选项
• 提供高达300mA电流
• 可配置PFM和强制PWM工作模式
为降低输入浪涌电流，器件提供内部固定软启动。器件也
具有EN/UVLO引脚，允许用户在输入电压达到相应要求时
开启器件。RESET开漏引脚可以用作输出电压监测。
应用
●
●
●
●
●
●
过程控制
工业传感器
4–20mA电流环
HVAC与楼宇控制
替代高压LDO
通用负载点电源
无需外部元件，降低总体成本
• 无需肖特基同步整流即可保持高效、低成本工作
• 内置补偿
• 3.3V和5V固定输出电压，内置反馈分压器
• 内部软启动
• 全陶瓷电容设计，提供紧凑布局
● 降低功耗
• 效率高达92%
• PFM功能，轻载时保持高效
• 关断电流仅为2.2μA (典型值)
● 在恶劣工业环境下工作可靠
• 打嗝式限流和自动重试启动
• 内置输出电压监测，带有RESET开漏引脚
• 可编程EN/UVLO门限
• 启动时单调进入预偏置输出
• 过热保护
• -40°C至+125°C汽车级/工业级温度范围
典型工作电路
定购信息和在数据资料的最后给出。
相关型号以及配合该器件使用的推荐产品，请参见：china.maximintegrated.
com/MAX15062.related。
VIN
4.5V TO
60V CIN
1µF
VIN
EN/UVLO
LX
GND
L1
33µH
COUT
10µF
VOUT
3.3V,
300mA
MAX15062A
CVCC
1µF
VCC
MODE
RESET
VOUT
本文是英文数据资料的译文，文中可能存在翻译上的不准确或错误。如需进一步确认，请在您的设计中参考英文资料。
有关价格、供货及订购信息，请联络Maxim亚洲销售中心：10800 852 1249 (北中国区)，10800 152 1249 (南中国区)，
或访问Maxim的中文网站：china.maximintegrated.com。
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
Absolute Maximum Ratings
VIN to GND...............................................................-0.3V to 70V
EN/UVLO to GND....................................................-0.3V to 70V
LX to GND..................................................... -0.3V to VIN + 0.3V
VCC, FB/VOUT, RESET to GND................................-0.3V to 6V
MODE to GND..............................................-0.3V to VCC + 0.3V
LX total RMS Current......................................................±800mA
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (TA = +70°C)
8-Pin TDFN (derate 6.2mW/NC above +70°C)............496mW
Operating Temperature Range.......................... -40°C to +125°C
Junction Temperature.......................................................+150°C
Storage Temperature Range............................. -65°C to +150°C
Soldering Temperature (reflow)........................................+260°C
Lead Temperature (soldering, 10s).................................. +300°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.
Package Thermal Characteristics (Note 1)
TDFN
Junction-to-Ambient Thermal Resistance (θJA).......+162°C/W
Junction-to-Case Thermal Resistance (θJC)..............+20°C/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
Electrical Characteristics
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, LX = MODE = RESET = unconnected; TA = TJ = -40°C to +125°C, unless
otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
INPUT SUPPLY (VIN)
Input Voltage Range
Input Shutdown Current
Input Supply Current
VIN
4.5
60
V
IIN-SH
VEN/UVLO = 0V, shutdown mode
2.2
4
µA
IQ-PFM
MODE = unconnected,
FB/VOUT = 1.03 x FB/VOUT-REG
95
160
µA
IQ-PWM
Normal switching mode, VIN = 24V
2.5
4
mA
ENABLE/UVLO (EN/UVLO)
EN/UVLO Threshold
VENR
VEN/UVLO rising
1.19
1.215
1.24
VENF
VEN/UVLO falling
1.06
1.09
1.15
V
+100
nA
VEN-TRUESD VEN/UVLO falling, true shutdown
EN/UVLO Input Leakage Current
IEN/UVLO
0.75
VEN/UVLO = 60V, TA = +25°C
-100
6V < VIN < 60V, 0mA < IVCC < 10mA
4.75
5
5.25
V
13
30
50
mA
0.15
0.3
V
LDO (VCC)
VCC Output Voltage Range
VCC Current Limit
VCC Dropout
VCC UVLO
Maxim Integrated
VCC
IVCC-MAX VCC = 4.3V, VIN = 12V
VCC-DO
VIN = 4.5V, IVCC = 5mA
VCC-UVR
VCC rising
4.05
4.18
4.3
VCC-UVF
VCC falling
3.7
3.8
3.95
V
2
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
Electrical Characteristics (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, LX = MODE = RESET = unconnected; TA = TJ = -40°C to +125°C, unless
otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
POWER MOSFETs
High-Side pMOS On-Resistance
RDS-ONH
ILX = 0.3A
(sourcing)
TA = +25°C
Low-Side nMOS On-Resistance
RDS-ONL
ILX = 0.3A
(sinking)
TA = +25°C
LX Leakage Current
ILX-LKG
1.35
TA = TJ = +125°C
2.7
0.45
TA = TJ = +125°C
VEN/UVLO = 0V, VIN = 60V, TA = +25°C,
VLX = (VGND + 1V) to (VIN - 1V)
1.75
0.55
0.9
-1
+1
Ω
Ω
µA
SOFT-START (SS)
Soft-Start Time
tSS
4.1
ms
FEEDBACK (FB)
FB Regulation Voltage
FB Leakage Current
VFB-REG
IFB
MODE = GND, MAX15062C
0.887
0.9
0.913
MODE = unconnected, MAX15062C
0.887
0.915
0.936
MAX15062C
-100
-25
MODE = GND, MAX15062A
3.25
3.3
3.35
MODE = unconnected, MAX15062A
3.25
3.35
3.42
MODE = GND, MAX15062B
4.93
5
5.07
MODE = unconnected, MAX15062B
4.93
5.08
5.18
V
nA
OUTPUT VOLTAGE (VOUT)
VOUT Regulation Voltage
VOUT-REG
V
CURRENT LIMIT
Peak Current-Limit Threshold
IPEAK-LIMIT
0.49
0.56
0.62
A
Runaway Current-Limit Threshold
IRUNAWAY-
0.58
0.66
0.73
A
Negative Current-Limit Threshold
ISINK-LIMIT
0.25
0.3
0.35
A
PFM Current Level
LIMIT
MODE = GND
IPFM
0.01
mA
0.13
A
TIMING
Switching Frequency
fSW
465
Events to Hiccup After Crossing
Runaway Current Limit
62.5
Hiccup Timeout
Maximum Duty Cycle
Maxim Integrated
535
1
FB/VOUT Undervoltage Trip Level
to Cause Hiccup
Minimum On-Time
500
64.5
Cycles
66.5
131
tON-MIN
DMAX
FB/VOUT = 0.98 x FB/VOUT-REG
89
kHz
%
ms
90
130
ns
91.5
94
%
3
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
Electrical Characteristics (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, LX = MODE = RESET = unconnected; TA = TJ = -40°C to +125°C, unless
otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
RESET
VOUT Threshold for RESET Rising VOUT-OKR VOUT rising
VOUT Threshold for RESET
Falling
VOUT-OKF VOUT falling
94
95.5
97
%
90.5
92
93.5
%
RESET Delay After VOUT
Reaches 95% Regulation
2
ms
RESET Output Level Low
IRESET = 5mA
0.2
V
RESET Output Leakage Current
VOUT = 1.01 x VOUT-REG,TA = +25°C
0.1
µA
MODE
MODE Internal Pullup Resistor
500
kΩ
166
°C
10
°C
THERMAL SHUTDOWN
Thermal-Shutdown Threshold
Temperature rising
Thermal-Shutdown Hysteresis
Note 2: All the limits are 100% tested at TA = +25°C. Limits over temperature are guaranteed by design.
Maxim Integrated
4
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
70
VIN = 36V
50
50
FIGURE 5 APPLICATION
CIRCUIT, PFM MODE
VOUT = 3.3V
VIN = 48V
10
1
40
30
100
10
1
LOAD CURRENT (mA)
toc02b
VIN = 24V
40
EFFICIENCY (%)
EFFICIENCY (%)
80
VIN = 36V
VIN = 48V
VIN = 60V
50
1
FIGURE 8 APPLICATION
CIRCUIT, PFM MODE
VOUT = 12V
10
70
VIN = 24V
60
VIN = 36V
50
VIN = 48V
40
30
20
10
0
100
0
EFFICIENCY vs. LOAD CURRENT
toc04a
50
EFFICIENCY (%)
EFFICIENCY (%)
VIN = 12V
60
VIN = 24V
50
VIN = 36V
40
VIN = 48V
20
10
0
50
100
FIGURE 7 APPLICATION
CIRCUIT, PWM MODE
VOUT = 2.5V
150
200
LOAD CURRENT (mA)
Maxim Integrated
10
200
250
300
250
EFFICIENCY vs. LOAD CURRENT
80
70
60
VIN = 36V
50
VIN = 48V
40
30
20
FIGURE 6 APPLICATION
CIRCUIT, PWM MODE
VOUT = 5V
10
0
300
0
50
100
150
200
EFFICIENCY VS. LOAD CURRENT
OUTPUT VOLTAGE
vs. LOAD CURRENT
3.37
toc04b
VIN = 18V
VIN = 24V
60
VIN = 36V
50
40
VIN = 48V
30
VIN = 60V
20
10
50
100
FIGURE 8 APPLICATION
CIRCUIT, PWM MODE
VOUT = 12V
150
200
LOAD CURRENT (mA)
250
300
250
300
FIGURE 5 APPLICATION
CIRCUIT, PFM MODE
3.36
0
VIN = 12V
VIN = 24V
LOAD CURRENT (mA)
70
0
100
LOAD CURRENT (mA)
80
70
30
150
FIGURE 7 APPLICATION
CIRCUIT, PFM MODE
VOUT = 2.5V
90
90
80
0
100
100
VIN = 6V
90
1
100
FIGURE 5 APPLICATION
CIRCUIT, PWM MODE
VOUT = 3.3V
LOAD CURRENT (mA)
100
VIN = 48V
LOAD CURRENT (mA)
80
60
50
20
100
VIN = 12V
90
70
VIN = 24V
VIN = 36V
30
EFFICIENCY vs. LOAD CURRENT
100
VIN = 18V
90
60
LOAD CURRENT (mA)
EFFICIENCY vs. LOAD CURRENT
100
70
40
FIGURE 6 APPLICATION
CIRCUIT, PFM MODE
VOUT = 5V
VIN = 48V
EFFICIENCY (%)
30
VIN = 36V
60
80
OUTPUT VOLTAGE (V)
40
70
VIN = 12V
90
MAX15062 toc04
60
80
VIN = 6V
3.35
MAX15062 toc05
EFFICIENCY (%)
80
VIN = 24V
90
EFFICIENCY (%)
VIN = 24V
VIN = 12V
toc02a
100
MAX15062 toc03
90
EFFICIENCY (%)
MAX15062 toc01
VIN = 12V
EFFICIENCY vs. LOAD CURRENT
EFFICIENCY vs. LOAD CURRENT
100
MAX15062 toc02
EFFICIENCY vs. LOAD CURRENT
100
VIN = 12V, 24V
3.34
3.33
VIN = 36V
3.32
VIN = 48V
3.31
3.30
3.29
0
50
100
150
200
250
300
LOAD CURRENT (mA)
5
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
OUTPUT VOLTAGE
vs. LOAD CURRENT
5.04
VIN = 12V, 36V, 48V
5.02
5.00
VIN = 12V
2.51
VIN = 6V,24V
2.50
VIN = 36V
VIN = 48V
2.49
2.48
50
100
150
200
0
LOAD CURRENT (mA)
0.920
toc06c
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
100
VIN = 12V
VIN = 6V, 24V
VIN = 36V
VIN = 48V
0.900
50
100
150
200
VIN = 36V
3.299
250
300
3.297
VIN = 24V
0
50
100
VIN = 12V
150
200
250
20
VIN = 48V,60V
0
50
40
60
TEMPERATURE (°C)
80
100 120
100
150
200
250
300
OUTPUT VOLTAGE
vs. LOAD CURRENT
5.003
FIGURE 6 APPLICATION
CIRCUIT, PWM MODE
5.002
5.001
VIN = 48V
5.000
4.999
4.997
300
VIN = 36V
VIN = 12V
0
50
100
VIN = 24V
150
200
250
300
LOAD CURRENT (mA)
5.04
MAX15062 toc09
FIGURE 5 APPLICATION
CIRCUIT, LOAD = 300mA
0
12.10
4.998
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
3.29
-20
VIN = 36V
LOAD CURRENT (mA)
3.30
-40
12.15
12.00
300
3.300
3.31
3.28
VIN = 24V
LOAD CURRENT (mA)
OUTPUT VOLTAGE
vs. TEMPERATURE
3.32
Maxim Integrated
250
VIN = 48V
3.301
LOAD CURRENT (mA)
3.27
200
FIGURE 5 APPLICATION
CIRCUIT, PWM MODE
3.298
0
150
OUTPUT VOLTAGE
vs. LOAD CURRENT
3.302
0.915
0.895
50
3.303
PFM MODE
0.905
12.20
LOAD CURRENT (mA)
FEEDBACK VOLTAGE
vs. LOAD CURRENT
0.910
VIN = 18V
12.05
2.47
300
250
12.25
OUTPUT VOLTAGE vs. TEMPERATURE
MAX15062 toc10
0
FIGURE 8 APPLICATION
CIRCUIT, PFM MODE
12.30
OUTPUT VOLTAGE (V)
4.98
2.52
toc06b
MAX15062 toc08
VIN = 24V
FIGURE 7 APPLICATION
CIRCUIT, PFM MODE
2.53
OUTPUT VOLTAGE
vs. LOAD CURRENT
12.35
OUTPUT VOLTAGE (V)
5.06
toc06a
MAX15062 toc07
OUTPUT VOLTAGE (V)
5.08
2.54
OUTPUT VOLTAGE (V)
FIGURE 6 APPLICATION
CIRCUIT, PFM MODE
MAX15062 toc06
5.10
OUTPUT VOLTAGE
vs. LOAD CURRENT
5.02
5.00
4.98
4.96
4.94
FIGURE 6 APPLICATION
CIRCUIT, LOAD = 300mA
-40
-20
0
20
40
60
80
100 120
TEMPERATURE (°C)
6
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE
FEEDBACK VOLTAGE
VS. TEMPERATURE
toc10a
NO-LOAD SUPPLY CURRENT (µA)
0.900
0.896
0.892
0.888
0.884
0
20
40
60
80
92
120
PFM MODE
5
15
25
35
45
NO-LOAD SUPPLY CURRENT
vs. TEMPERATURE
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX15062 toc12
INPUT VOLTAGE (V)
110
100
90
80
6
55
5
4
3
2
1
PFM MODE
-40 -20
0
20
40
60
80
0
100 120
5
35
45
SHUTDOWN CURRENT
vs. TEMPERATURE
SWITCH CURRENT LIMIT
vs. INPUT VOLTAGE
2.10
1.95
1.80
1.65
600
550
0
20
40
60
80
TEMPERATURE (°C)
100 120
55
SWITCH PEAK CURRENT LIMIT
500
450
400
350
300
SWITCH NEGATIVE CURRENT LIMIT
250
-20
25
INPUT VOLTAGE (V)
2.25
-40
15
TEMPERATURE (°C)
MAX15062 toc15
70
2.40
SHUTDOWN CURRENT (µA)
100
120
Maxim Integrated
94
TEMPERATURE (°C)
MAX15062 toc14
NO-LOAD SUPPLY CURRENT (µA)
-20
130
1.50
96
MAX15062 toc13
-40
140
60
98
90
SHUTDOWN CURRENT (µA)
0.880
SWITCH CURRENT LIMIT (mA)
FEEDBACK VOLTAGE (V)
0.904
MAX15062 toc11
100
0.908
200
5
15
25
35
45
55
INPUT VOLTAGE (V)
7
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
450
400
350
SWITCH NEGATIVE CURRENT LIMIT
250
200
-40
-20
20
40
60
80
1.18
1.16
1.14
1.12
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
SWITCHING FREQUENCY
vs. TEMPERATURE
RESET THRESHOLD
vs. TEMPERATURE
520
500
480
460
98
100 120
97
96
RISING
95
94
93
FALLING
92
91
-40
-20
0
20
40
60
80
100 120
90
0
10
20
30
40
50
60
TEMPERATURE (°C)
TEMPERATURE (°C)
LOAD TRANSIENT RESPONSE,
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
LOAD TRANSIENT RESPONSE,
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
MAX15062 toc21
MAX15062 toc20
VOUT (AC)
100mV/div
VOUT (AC)
100mV/div
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
IOUT
100mA/div
IOUT
100mA/div
100µs /div
Maxim Integrated
FALLING
1.10
TEMPERATURE (°C)
540
440
1.20
1.08
100 120
MAX15062 toc18
SWITCHING FREQUENCY (kHz)
560
0
RISING
1.22
MAX15062 toc19
300
MAX15062 toc17
SWITCH PEAK CURRENT LIMIT
500
EN/UVLO THRESHOLD VOLTAGE (V)
550
EN/UVLO THRESHOLD
vs. TEMPERATURE
1.24
RESET THRESHOLD (%)
SWITCH CURRENT LIMIT (mA)
600
MAX15062 toc16
SWITCH CURRENT LIMIT
vs. TEMPERATURE
100µs /div
8
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
LOAD TRANSIENT RESPONSE
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
LOAD TRANSIENT RESPONSE,
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
toc21b
toc21a
VOUT (AC)
200mV/div
VOUT (AC)
100mV/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
IOUT
100mA/div
IOUT
100mA/div
100µs/div
100µs/div
LOAD TRANSIENT RESPONSE,
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
LOAD TRANSIENT RESPONSE,
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
MAX15062 toc22
MAX15062 toc23
VOUT (AC)
100mV/div
VOUT (AC)
100mV/div
IOUT
100mA/div
IOUT
100mA/div
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
40µs/div
40µs/div
LOAD TRANSIENT RESPONSE
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
LOAD TRANSIENT RESPONSE
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
toc23a
VOUT (AC)
50mV/div
toc23b
VOUT (AC)
200mV/div
IOUT
100mA/div
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
40µs/div
Maxim Integrated
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
IOUT
100mA/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
40µs/div
9
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
LOAD TRANSIENT RESPONSE,
PWM MODE (LOAD CURRENT
STEPPED FROM NO LOAD TO 150mA)
LOAD TRANSIENT RESPONSE,
PWM MODE PWM mode (LOAD CURRENT
STEPPED FROM NO LOAD TO 150mA)
MAX15062 toc24
VOUT (AC)
100mV/div
MAX15062 toc25
VOUT (AC)
100mV/div
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
IOUT
100mA/div
IOUT
100mA/div
40µs/div
40µs/div
LOAD TRANSIENT RESPONSE
PWM MODE (LOAD CURRENT STEPPED
FROM NO LOAD TO 150mA)
LOAD TRANSIENT RESPONSE
PWM MODE (LOAD CURRENT STEPPED
FROM NO LOAD TO 150mA)
toc25b
toc25a
VOUT (AC)
VOUT (AC)
200mV/div
50mV/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
IOUT
100mA/div
IOUT
100mA/div
40µs/div
40µs/div
FULL-LOAD SWITCHING WAVEFORMS
(PWM OR PFM MODE)
SWITCHING WAVEFORMS
(PFM MODE)
MAX15062 toc27
MAX15062 toc26
VOUT (AC)
100mV/div
FIGURE 6 APPLICATION CIRCUIT
VOUT = 5V, LOAD = 20mA
VOUT (AC)
20mV/div
VLX
10V/div
VLX
10V/div
IOUT
200mA/div
IOUT
100mA/div
10µs/div
Maxim Integrated
VOUT = 5V,
LOAD = 300mA
2µs/div
10
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
NO-LOAD SWITCHING WAVEFORMS
(PWM MODE)
SOFT-START
MAX15062 toc28
VOUT = 5V
MAX15062 toc29
VEN/UVLO
5V/div
VOUT (AC)
20mV/div
VLX
10V/div
VOUT
1V/div
IOUT
100mA/div
IOUT
100mA/div
VRESET
5V/div
2µs/div
SOFT-START
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
1ms/div
SOFT-START
toc30a
MAX15062 toc30
VEN/UVLO
5V/div
VEN/ UVLO
5V/div
VOUT
1V/div
VOUT
1V/div
IOUT
100mA/div
VRESET
5V/div
IOUT
100mA/div
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
VRESET
5V/div
1ms/div
1ms/div
SOFT-START
SHUTDOWN WITH ENABLE
MAX15062 toc31
toc30b
VEN/UVLO
VEN/UVLO
5V/div
5V/div
VOUT
1V/div
VOUT
5V/div
IOUT
100mA/div
IOUT
100mA/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
VRESET
5V/div
1ms/div
Maxim Integrated
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
VRESET
5V/div
400µs /div
11
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
典型工作特性(续)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
SOFT-START WITH 3V PREBIAS
OVERLOAD PROTECTION
MAX15062 toc32
MAX15062 toc33
VEN/ UVLO
5V/div
VIN
20V/div
VOUT
1V/div
VOUT
2V/div
FIGURE 6
APPLICATION CIRCUIT
NO LOAD
PWM MODE
IOUT
200mA/div
VRESET
5V/div
1ms/div
144
40
108
30
72
20
10
36
10
0
0
40
GAIN
30
PHASE
20
fCR = 47kHz,
PHASE MARGIN = 59°
-10
-20
FIGURE 5 APPLICATION CIRCUIT
VOUT = 3.3V
-30
-40
-50
-36
2
4 6 81
1k
2
4 6 81
10k
2
100k
GAIN (dB)
50
PHASE (°)
180
BODE PLOT
-108
-30
-144
-40
-180
-50
30
GAIN (dB)
20
PHASE
10
0
FIGURE 7 APPLICATION CIRCUIT
VOUT = 2.5V
-40
-50
1k
10k
FREQUENCY (Hz)
Maxim Integrated
144
40
108
30
72
20
36
10
-36
-20
-30
50
0
fCR = 43kHz,
PHASE MARGIN = 60°
-10
180
100k
GAIN (dB)
MAX15062 toc35a
GAIN
40
0
fCR = 47kHz,
PHASE MARGIN = 60°
-36
-72
FIGURE 6 APPLICATION CIRCUIT
VOUT = 5V
2
1k
4 6 81
2
4 6 81
10k
2
100k
-108
-144
-180
FREQUENCY (Hz)
PHASE (°)
BODE PLOT
72
36
FREQUENCY (Hz)
50
108
PHASE
-10
-20
180
144
GAIN
0
-72
MAX15062 toc35
PHASE (°)
MAX15062 toc34
BODE PLOT
-108
-30
-144
-40
-180
-50
108
PHASE
72
36
0
fCR = 36kHz,
PHASE MARGIN = 66°
-10
-20
180
144
GAIN
0
-72
MAX15062 toc35b
-36
PHASE (°)
BODE PLOT
50
GAIN (dB)
20ms/div
-72
FIGURE 8 APPLICATION CIRCUIT
VOUT = 12V
1k
10k
100k
-108
-144
-180
FREQUENCY (Hz)
12
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
引脚配置
TOP VIEW
LX
GND
RESET
MODE
8
7
6
5
MAX15062
+
1
2
3
4
VIN
EN/UVLO
VCC
FB/VOUT
TDFN
(2mm x 2mm)
引脚说明
引脚
名称
1
VIN
2
EN/UVLO
3
VCC
4
FB/VOUT
5
MODE
PFM/PWM模式选择输入。MODE连接至GND时，使能固定频率PWM工作；浮空时，工作在轻载PFM模
式。
6
RESET
开漏复位输出，利用外部电阻将RESET拉高至外部电源。
当输出电压下降至设定标称稳压值的92%以下时，RESET为低电平；输出电压上升2ms电阻至稳压值的
95%以上时，RESET返回高电平。门限值请参见Electrical Characteristics表。
7
GND
8
LX
Maxim Integrated
说明
开关稳压器电源输入。在VIN和GND之间连接旁路陶瓷电容X7R 1μF。
高电平有效使能/欠压检测输入。将EN/UVLO拉低至GND时，禁止稳压器输出；将EN/UVLO连接至V IN
时，始终保持有效工作。在VIN及EN/UVLO与GND之间连接电阻分压器，设置器件使能/开启时的输入电
压。
内部LDO电源输出，利用最小1μF电容将VCC旁路至GND。
反馈电源输入，将FB/VOUT直接连接至输出。对于固定输出电压版本， 在VOUT和GND之间，连接FB/
VOUT到一个电阻分压器，用来调节0.9V至0.89 x VIN的输出电压。
地。将GND连接至电源接地区域。通过单点将所有电路地连接在一起，参见PCB布局指南部分。
电感连接。将LX连接至电感的开关侧。器件处于关断模式时，LX为高阻。
13
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
方框图
VIN
LDO
REGULATOR
PEAK-LIMIT
RUNAWAYCURRENTLIMIT
SENSE
LOGIC
PFM
VCC
MAX15062
CS
CURRENTSENSE
AMPLIFIER
POK
EN/UVLO
DH
CHIPEN
HIGH-SIDE
DRIVER
1.215V
THERMAL
SHUTDOWN
VCC
CLK
LX
OSCILLATOR
SLOPE
500kΩ
MODE
MODE SELECT
0.55VCC
PFM/PWM
CONTROL
LOGIC
DL
LOW-SIDE
DRIVER
SLOPE
CS
FB/VOUT
R1
*
PWM
ERROR
AMPLIFIER
R2
REFERENCE
SOFT-START
CLK
*RESISTOR-DIVIDER ONLY FOR MAX15062A, MAX15062B
Maxim Integrated
SINK-LIMIT
LOW-SIDE
CURRENT
SENSE
NEGATIVE
CURRENT
REF
3.135V FOR MAX15062A
4.75V FOR MAX15062B
0.859V FOR MAX15062C
FB/VOUT
GND
RESET
2ms
DELAY
14
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
详细说明
MAX15062高 效、 高 压、 同 步 降 压 型DC-DC转 换 器 内
部集成了M O S F E T，工作在4.5V至60V宽输入电压范
围。 转 换 器 提 供 高 达300mA的 输 出 电 流， 输 出 电 压 为
3.3V (MAX15062A)、5V (MAX15062B)和 可 调 输 出 电 压
(MAX15062C)。满足EN/UVLO和VCC UVLO时，内部软启
动电路控制误差放大器基准开启，提供确定的单调输出电
压软启动，与负载电流无关。FB/VOUT引脚通过内部电阻
分压器监测输出电压。输出电压达到稳压值的95% 2ms后，
RESET置于高阻态。根据上电时MODE引脚的状态，器件
选择PFM或强制PWM工作模式。通过拉低EN/UVLO引脚，
器件进入关断模式，待机电流仅为2.2μA (典型值)。
DC-DC开关稳压器
器件采用内部补偿、固定频率、电流模式控制架构(方框图 部 分)。 在 内 部 时 钟 的 上 升 沿， 高 边pMOSFET导 通。 内
部误差放大器将反馈电压与内部基准固定电压进行比
较， 产 生 误 差 电 压； 由PWM比 较 器 将 误 差 电 压 与 电 流
检测电压和斜率补偿电压之和进行比较，设置导通时间。 pMOSFET导通期间，电感电流线性爬升。在开关周期的其
余时间(关闭时间)，pMOSFET保持关断，低边nMOSFET 导通。关断期间，随着电感电流下降，电感释放储能，为
输出提供电流。过载条件下，逐周期限流电路通过关闭高
边pMOSFET、导通低边nMOSFET限制电感的峰值电流。
模式选择(MODE)
在VCC和EN/UVLO电压超过相应UVLO上升门限，同时内
部电压就绪、允许LX进行开关工作后，锁存MODE引脚的
逻辑状态。如果MODE引脚在上电时浮空，器件在轻载时
工作在PFM模式；如果MODE引脚在上电时接地，器件在
所有负载条件下工作在固定频率PWM模式。常规工作期
间，忽略MODE引脚的状态变化。
PWM工作模式
固定的开关频率。然而，相对于PFM工作模式，PWM模
式在轻载条件下效率较低。
PFM工作模式
PFM工作模式可消除负向电感电流以及轻载下额外的跳脉
冲，以获得较高效率。PFM模式下，每时钟周期的电感电
流峰值强制为固定的130mA，直到输出上升到标称电压的
102.3%。输出达到标称电压的102.3%后，关断高边和低
边FET，器件进入深度休眠状态，直到负载将输出放电至
标称电压的101.1%。深度休眠模式下，大部分内部电路
关断，以节约静态电流。输出下降至标称电压的101.1%
以下时，器件退出深度休眠模式，打开全部内部电路，再
次以脉冲方式开始向输出传送能量，直到输出达到标称输
出电压的102.3%。当负载电流超过55mA (典型值)时，器
件自然进入PFM模式。PFM模式的优点是轻载下消耗极低
的静态电流，因此获得较高效率。
内部5V线性稳压器
内部稳压器提供5V标称电压，为内部功能电路供电，并
驱动功率MOSFET。应利用1μF电容将线性稳压器的输出
(VCC)旁路至GND。VCC稳压器压差的典型值为150mV。当
VCC下降至3.8V(典型值)以下时，欠压锁定电路关断稳压器。
400mV VCC UVLO滞回可防止上电、关断时的抖动。
使能输入(EN/UVLO)、软启动
当EN/UVLO电压高于1.21V (典型值)时，器件内部的误差
放大器基准电压开始上升。软启动上升持续时间为4.1ms，
允许输出电压平稳地增大。将EN/UVLO驱动为低电平时，
关断两个功率MOSFET及其它内部电路，将VIN静态电流降
低至2.2μA以下。EN/UVLO可用作输入电压UVLO调节输
入。VIN及EN/UVLO与GND之间的外部分压器控制器件开
启或关断时的输入电压。如果不需要设置输入UVLO，将
EN/UVLO连接至VIN (关于EN/UVLO上升和下降门限电压，
请参见Electrical Characteristics 表)。
PWM模式下，允许电感电流出现负值。在对频率敏感的
应用中，PWM工作模式非常有用，任何负载条件下保持
Maxim Integrated
15
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
复位输出(RESET)
器件包括开漏输出RESET，以监测输出电压。输出电压上
升至其标称电压的95%以上2ms后，RESET变为高电平；
输出电压跌落到标称稳压值的92%以下时，RESET拉低。
打嗝超时周期内，触发RESET输出低电平。
启动时进入预偏置输出
器 件 能 够 在 软 启 动 时 进 入 预 偏 置 输 出， 在PFM和 强 制
PWM模式下都无需对输出电容放电。对于需要多路电源
供电的数字集成电路应用，该功能非常有用。
输入电压工作范围
最高输入工作电压由最小导通时间决定，最低输入工作电
压由最大占空比及电路压差决定。给定输出电压的最小和
最大工作输入电压，计算如下：
VINMIN
VOUT + (I OUT × (R DCR + 0.5))
+ (I OUT × 1.0)
D MAX
VINMAX =
VOUT
t ONMIN × f SW
式中，VOUT为稳态输出电压，IOUT为最大负载电流，RDCR
为电感的直流电阻，fSW为开关频率(最大值)，DMAX为最
大占空比(0.9)，tONMIN为最差工作条件下的最小开关导通
时间(130ns)。
过流保护/打嗝模式
周期峰值限流电路将断开高边MOSFET。高输入电压、短
路条件(输出电压不足以恢复降压转换器导通期间建立的电
感电流)下，高边开关0.66A (典型值)失控电流检测门限将
为器件提供有效保护。一旦达到失控电流门限，则触发打
嗝模式。此外，完成软启动后，如果输出电压在任何时间
因为故障条件而下降到标称电压的65% (典型值)，同样触
发打嗝模式。打嗝模式下，在打嗝超时周期(31ms)内暂停
开关工作，保护转换器。达到打嗝超时周期后，再次尝试
软启动。打嗝工作模式确保输出短路条件下保持低功耗。
电路板布局及系统连接时应谨慎，防止在短路条件下FB/
VOUT引脚超过绝对最大额定值。此类条件下，陶瓷输出电
容可能会随输出电容或短路负载之间的电路板或接线电感
发生振荡，造成FB/VOUT (-0.3V)超过绝对最大额定值。应
将寄生电路板或接线电感降至最小，并验证短路条件下的
输出电压波形，确保FB/VOUT不超过绝对最大额定值。
热过载保护
热过载保护限制器件的总功耗。结温超过+166°C时，片上
温度传感器关断器件，关闭内部功率MOSFET，允许器件
冷却。结温降低10°C后，温度传感器控制器件恢复工作。
应用信息
电感选择
在保证尺寸合适的前提下，应选择直流电阻最低的低损耗
电感。饱和电流(ISAT)必须足够高，确保在0.56A (典型值)最
大限流(IPEAK-LIMIT)的条件下不发生饱和。对于5V和3.3V固
定输出电压、300mA负载电流应用，请参见表1选择电感。
器件具有可靠的过流保护机制，在过载和输出短路条件下
有效保护器件。高边开关电流超过0.56A (典型值)时，逐
Maxim Integrated
16
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
表1. 电感选择
INPUT VOLTAGE
RANGE VIN (V)
VOUT (V)
IOUT (mA)
L (µH)
4.5 to 60
3.3 (Fixed)
300
33
Coilcraft LPS4018-333ML
6 to 60
5 (Fixed)
300
47
Coilcraft LPS4018-473ML
4.5 to 60
1.8 or 2.5
300
22
Coilcraft LPS4018-223ML
14 to 60
12
300
100
Wurth 74408943101
17 to 60
15
300
150
TDK VLC6045T-151M
RECOMMENDED PART NO.
表2. 输入和输出电容选择
INPUT VOLTAGE
RANGE VIN (V)
VOUT (V)
IOUT (mA)
COUT (µF)
4.5 to 60
3.3 (Fixed)
300
10µF/1206/X7R/6.3V
Murata GRM31CR70J106K
RECOMMENDED PART NO.
6 to 60
5 (Fixed)
300
10µF/1206/X7R/6.3V
Murata GRM31CR70J106K
4.5 to 60
1.8 or 2.5
300
22µF/1206/X7R/6.3V
Murata GRM31CR70J226K
14 to 60
12
300
4.7µF/1206/X7R/16V
Murata GRM31CR71C475K
17 to 60
15
300
4.7µF/1206/X7R/25V
Murata GRM31CR71E475K
VIN
VIN
R1
MAX15062
的内部控制环路。合理选择输出电容，通常使其能够在最
大50%的负载电流跃变，确保输出电压偏差小于3%。器
件需要至少10μF电容保证稳定工作，可利用下式计算必需
的输出电容：
EN/UVLO
R2
C OUT =
30
VOUT
图1. 可调节EN/UVLO网络
式中，COUT为μF输出电容，而VOUT为输出电压。典型应用，
请参考表2选择输出电容。
输入电容
设置输入欠压锁定电平
推荐器件使用小尺寸陶瓷电容。输入电容降低来自于电源
的尖峰电流，减小开关电路引起的输入噪声和电压纹波。
推荐使用最小1μF、X7R、封装大于0805的电容作为器件
的输入电容，保证输入电压纹波小于最小输入电压的2%，
并满足最大纹波电流要求。对于固定5V和3.3V输出电压、
300mA负载电流应用，请参见表2选择输入电容。
可调节器件的输入欠压锁定电平。利用VIN和GND之间连
接的电阻分压器(见图1)设置器件开启工作时的电压。将分
压器的中间节点连接至EN/UVLO。
输出电容
小尺寸陶瓷X7R电容即足以满足多数应用的要求。输出电
容有两种功能：滤除器件以及输出电感产生的纹波；储存
足够的能量，在负载瞬变条件下支撑输出电压并稳定器件
Maxim Integrated
选择R1，最大3.3MΩ，按下式计算R2：
R2 =
R1× 1.215
(VINU - 1.215)
式中，VINU为开启器件工作所要求的电压。
17
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
调节输出电压
PCB布局指南
MAX15062C输出电压可设置为0.9V至0.89 x VIN。通过在
输出至FB及GND之间连接电阻分压器，设定输出电压(见
图2)。
严谨的PCB布局(见图2)是实现干净、稳定工作的关键，尤
其是功率开关级，需要特别注意。遵循以下原则有助于获
得良好的PCB布局：
对于小于6V的输出电压，在50kΩ至150kΩ范围内选择R2；
对于大于6V的输出电压，在25kΩ至75kΩO范围内选择R2，
然后利用下式计算R1：
● 输入陶瓷电容尽量靠近VIN和GND引脚放置。
V
= R2 ×  OUT
R1
 0.9
−

1

● 利用最短走线或接地区域将VCC旁路电容的负端点连接
至GND。
● 将LX引脚和电感连接形成的区域降至最小，减小EMI辐
射。
● VCC去抖电容尽量靠近VCC引脚放置。
功耗
● 确保所有反馈连线短而直。
应确保器件结温在规定电源工作条件下不超过+125°C。特
定工作条件下，按下式估算导致器件温度升高的功耗：
点高速开关节点(LX)远离FB/VOUT、RESET和MODE引脚。

 1 
2
PLOSS =
POUT ×  - 1  - (I OUT × R DCR )
η



P=
V
OUT
OUT × I OUT
可参考MAX15062评估板，将其作为PCB布局实例，从以
下网站下载：china.maximintegrated.com。
VOUT
R1
式中，POUT为输出功率，η为电源转换效率，RDCR为输
出电感的直流电阻。关于电源转换效率或通过测量效率确
定总功耗的信息，请参见典型工作特性 部分。
FB
MAX15062C
可利用下式估算器件在任意给定环境温度(TA)下的结温
(TJ)：
R2
GND
TJ= T A + (θ JA × PLOSS )
式中，θJA为封装结至环境的热阻。
Maxim Integrated
图2. 设置输出电压
18
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
VIN
VIN
CIN
LX
L1
VOUT
COUT
R1
GND
EN/UVLO
MAX15062A/B
R2
VOUT
VCC
VCC
CVCC
RESET
R3
MODE
VCC
VIN PLANE
CIN
U1
R1
LX
VIN
EN/UVLO
GND
VCC
R2
CVCC
L1
COUT
RESET
VOUT
MODE
R3
VIAS TO BOTTOM-SIDE GROUND PLANE
VIAS TO VOUT
GND
PLANE
VOUT PLANE
VIAS TO VCC
图3. MAX15062A和MAX15062B布局指南
Maxim Integrated
19
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
VIN
VIN
CIN
LX
L1
VOUT
COUT
R1
GND
EN/UVLO
R4
MAX15062C
R2
FB
VCC
R5
VCC
CVCC
RESET
R3
MODE
VCC
VIN PLANE
CIN
U1
R1
LX
VIN
EN/UVLO
GND
VCC
R2
CVCC
L1
COUT
RESET
FB
MODE
GND
PLANE
R5
VOUT PLANE
R4
R3
VIAS TO BOTTOM-SIDE GROUND PLANE
VIAS TO VOUT
VIAS TO VCC
图4. MAX15062C布局指南
Maxim Integrated
20
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
VIN
4.5V TO
60V
CIN
1µF
VIN
EN/UVLO
LX
L1
33µH
COUT
10µF
GND
VOUT
3.3V,
300mA
VIN
6V TO
60V
CIN
1µF
MAX15062A
CVCC
1µF
VCC
MODE
EN/UVLO
LX
COUT
10µF
GND
RESET
CVCC
1µF
VOUT
VCC
MODE
RESET
VOUT
MODE = GND FOR PWM
MODE = OPEN FOR PFM
MODE = GND FOR PWM
MODE = OPEN FOR PFM
L1: COILCRAFT LPS4018-333ML
COUT: MURATA 10µF/X7R/6.3V/1206 GRM31CR70J106K
CIN: MURATA 1µF/X7R/100V/1206 GRM31CR72A105K
L1: COILCRAFT LPS4018-473ML
COUT: MURATA 10µF/X7R/6.3V/1206 GRM31CR70J106K
CIN: MURATA 1µF/X7R/100V/1206 GRM31CR72A105K
CIN
1µF
VIN
EN/UVLO
图6. 5V、300mA降压型稳压器
LX
L1
22µH
GND
MAX15062C
CVCC
1µF
VCC
MODE
COUT
22µF
VOUT
2.5V,
300mA
CIN
1µF
R1
133kΩ
FB
RESET
VIN
14V TO
60V
EN/UVLO
LX
GND
MAX15062C
CVCC
1µF
R2
75kΩ
VIN
L1
100µH
VCC
MODE
RESET
MODE = GND FOR PWM
MODE = OPEN FOR PFM
L1: COILCRAFT LPS4018-223ML
COUT: MURATA 22µF/X7R/6.3V/1206 (GRM31CR70J226K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
L1: Wurth 74408943101
COUT: MURATA 4.7µF/X7R/16V/1206 (GRM31CR71C475K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
Maxim Integrated
COUT
4.7µF
VOUT
12V,
300mA
R1
499kΩ
FB
MODE = GND FOR PWM
MODE = OPEN FOR PFM
图7. 2.5V、300mA降压稳压器
VOUT
5V,
300mA
MAX15062B
图5. 3.3V、300mA降压型稳压器
VIN
4.5V TO
60V
VIN
L1
47µH
R2
40.2kΩ
图8. 12V、300mA降压稳压器
21
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
定购信息
VIN
4.5V TO
60V
CIN
1µF
VIN
LX
EN/UVLO
L1
22µH
COUT
22µF
GND
R1
75kΩ
MAX15062C
CVCC
1µF
R2
75kΩ
RESET
L1: COILCRAFT LPS4018-223ML
COUT: MURATA 22µF/X7R/6.3V/1206 (GRM31CR70J226K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
VIN
LX
EN/UVLO
GND
MAX15062AATA+
-40°C至+125°C
8 TDFN
3.3V
MAX15062BATA+
-40°C至+125°C
8 TDFN
5V
MAX15062CATA+
-40°C至+125°C
8 TDFN
Adj
芯片信息
COUT
4.7µF
VOUT
15V,
300mA
封装类型
封装编码
外形编号
焊盘布局编号
8 TDFN
T822CN+1
21-0487
90-0349
R1
499kΩ
FB
VCC
MODE
VOUT
如需最近的封装外形信息和焊盘布局(占位面积)，请查询china.
maximintegrated.com/packages。请注意，封装编码中的
“+”
、
“#”
或
“-”
仅表示RoHS状态。封装图中可能包含不同的尾缀字符， 但封
装图只与封装有关，与RoHS状态无关。
L1
150µH
MAX15062C
CVCC
1µF
引脚-封装
封装信息
图9. 1.8V、300mA降压稳压器
CIN
1µF
温度范围
PROCESS: BiCMOS
MODE = GND FOR PWM
MODE = OPEN FOR PFM
VIN
17V TO
60V
器件
+表示无铅(Pb)/符合RoHS标准的封装。
FB
VCC
MODE
VOUT
1.8V,
300mA
RESET
R2
31.6kΩ
MODE = GND FOR PWM
MODE = OPEN FOR PFM
L1: TDK VLC6045T-151M
COUT: MURATA 4.7µF/X7R/25V/1206 (GRM31CR71E475K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
图10. 15V、300mA降压稳压器
Maxim Integrated
22
MAX15062
60V、300mA、超小尺寸、高效、
同步降压型DC-DC转换器
修订历史
修订号
修订日期
说明
0
6/13
最初版本。
1
10/13
增加了MAX15062C、特性、全部更新了图像及表格。
修改页
—
1 -17
Maxim北京办事处
北京8328信箱 邮政编码100083
免费电话：800 810 0310
电话：010-6211 5199
传真：010-6211 5299
Maxim不对Maxim产品以外的任何电路使用负责，也不提供其专利许可。Maxim保留在任何时间、没有任何通报的前提下修改产品资料和规格的权利。电气
特性表中列出的参数值(最小值和最大值)均经过设计验证，数据资料其它章节引用的参数值供设计人员参考。
Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-10 00
23
© 2013 Maxim Integrated
Maxim标志和Maxim Integrated是Maxim Integrated Products, Inc.的商标。
EVALUATION KIT AVAILABLE
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
General Description
Benefits and Features
The device employs a peak-current-mode control architecture with a MODE pin that can be used to operate the
device in pulse-width modulation (PWM) or pulse-frequency modulation (PFM) control schemes. PWM operation provides constant frequency operation at all loads
and is useful in applications sensitive to variable switching frequency. PFM operation disables negative inductor
current and additionally skips pulses at light loads for high
efficiency. The low-resistance on-chip MOSFETs ensure
high efficiency at full load and simplify the PCB layout.
● Reduces Number of DC-DC Regulators to Stock
• Wide 4.5V to 60V Input Voltage Range
• Fixed 3.3V and 5V Output Voltage Options
• Adjustable 0.9V to 0.89 x VIN Output Voltage
Option
• Delivers Up to 300mA Load Current
• Configurable Between PFM and Forced-PWM
Modes
● Reduces Power Dissipation
• Peak Efficiency = 92%
• PFM Feature for High Light-Load Efficiency
• Shutdown Current = 2.2µA (typ)
The MAX15062 high-efficiency, high-voltage, synchronous
step-down DC-DC converter with integrated MOSFETs
operates over a 4.5V to 60V input voltage range. The
converter delivers output current up to 300mA at 3.3V
(MAX15062A), 5V (MAX15062B), and adjustable output
voltages (MAX15062C). The device operates over the
-40°C to +125°C temperature range and is available in a
compact 8-pin (2mm x 2mm) TDFN package. Simulation
models are available.
To reduce input inrush current, the device offers an
internal soft-start. The device also incorporates an EN/
UVLO pin that allows the user to turn on the part at the
desired input-voltage level. An open-drain RESET pin can
be used for output-voltage monitoring.
Applications
●
●
●
●
●
●
Process Control
Industrial Sensors
4–20mA Current Loops
HVAC and Building Control
High-Voltage LDO Replacement
General-Purpose Point-of-Load
Ordering Information appears at end of data sheet.
● Eliminates External Components and Reduces
Total Cost
• No Schottky—Synchronous Operation for High
Efficiency and Reduced Cost
• Internal Compensation
• Internal Feedback Divider for Fixed 3.3V, 5V
Output Voltages
• Internal Soft-Start
• All-Ceramic Capacitors, Ultra-Compact Layout
● Operates Reliably in Adverse Industrial Environments
• Hiccup-Mode Current Limit and Autoretry Startup
• Built-In Output Voltage Monitoring with Open-Drain
RESET Pin
• Programmable EN/UVLO Threshold
• Monotonic Startup into Prebiased Output
• Overtemperature Protection
• -40°C to +125°C Automotive/Industrial
Temperature Range
Typical Operating Circuit
VIN
4.5V TO
60V CIN
1µF
For related parts and recommended products to use with this part, refer
to www.maximintegrated.com/MAX15062.related.
VIN
EN/UVLO
GND
MAX15062A
CVCC
1µF
VCC
MODE
19-6685; Rev 1; 10/13
LX
RESET
VOUT
L1
33µH
COUT
10µF
VOUT
3.3V,
300mA
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Absolute Maximum Ratings
VIN to GND...............................................................-0.3V to 70V
EN/UVLO to GND....................................................-0.3V to 70V
LX to GND..................................................... -0.3V to VIN + 0.3V
VCC, FB/VOUT, RESET to GND................................-0.3V to 6V
MODE to GND..............................................-0.3V to VCC + 0.3V
LX total RMS Current......................................................±800mA
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (TA = +70°C)
8-Pin TDFN (derate 6.2mW/NC above +70°C)............496mW
Operating Temperature Range.......................... -40°C to +125°C
Junction Temperature.......................................................+150°C
Storage Temperature Range............................. -65°C to +150°C
Soldering Temperature (reflow)........................................+260°C
Lead Temperature (soldering, 10s).................................. +300°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.
Package Thermal Characteristics (Note 1)
TDFN
Junction-to-Ambient Thermal Resistance (θJA).......+162°C/W
Junction-to-Case Thermal Resistance (θJC)..............+20°C/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
Electrical Characteristics
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, LX = MODE = RESET = unconnected; TA = TJ = -40°C to +125°C, unless
otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
INPUT SUPPLY (VIN)
Input Voltage Range
Input Shutdown Current
Input Supply Current
VIN
4.5
60
V
IIN-SH
VEN/UVLO = 0V, shutdown mode
2.2
4
µA
IQ-PFM
MODE = unconnected,
FB/VOUT = 1.03 x FB/VOUT-REG
95
160
µA
IQ-PWM
Normal switching mode, VIN = 24V
2.5
4
mA
ENABLE/UVLO (EN/UVLO)
EN/UVLO Threshold
VENR
VEN/UVLO rising
1.19
1.215
1.24
VENF
VEN/UVLO falling
1.06
1.09
1.15
V
+100
nA
VEN-TRUESD VEN/UVLO falling, true shutdown
EN/UVLO Input Leakage Current
IEN/UVLO
0.75
VEN/UVLO = 60V, TA = +25°C
-100
6V < VIN < 60V, 0mA < IVCC < 10mA
4.75
5
5.25
V
13
30
50
mA
0.15
0.3
V
LDO (VCC)
VCC Output Voltage Range
VCC Current Limit
VCC Dropout
VCC UVLO
www.maximintegrated.com
VCC
IVCC-MAX VCC = 4.3V, VIN = 12V
VCC-DO
VIN = 4.5V, IVCC = 5mA
VCC-UVR
VCC rising
4.05
4.18
4.3
VCC-UVF
VCC falling
3.7
3.8
3.95
V
Maxim Integrated │ 2
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Electrical Characteristics (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, LX = MODE = RESET = unconnected; TA = TJ = -40°C to +125°C, unless
otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
POWER MOSFETs
High-Side pMOS On-Resistance
RDS-ONH
ILX = 0.3A
(sourcing)
TA = +25°C
Low-Side nMOS On-Resistance
RDS-ONL
ILX = 0.3A
(sinking)
TA = +25°C
LX Leakage Current
ILX-LKG
1.35
TA = TJ = +125°C
2.7
0.45
TA = TJ = +125°C
VEN/UVLO = 0V, VIN = 60V, TA = +25°C,
VLX = (VGND + 1V) to (VIN - 1V)
1.75
0.55
0.9
-1
+1
Ω
Ω
µA
SOFT-START (SS)
Soft-Start Time
tSS
4.1
ms
FEEDBACK (FB)
FB Regulation Voltage
FB Leakage Current
VFB-REG
IFB
MODE = GND, MAX15062C
0.887
0.9
0.913
MODE = unconnected, MAX15062C
0.887
0.915
0.936
MAX15062C
-100
-25
MODE = GND, MAX15062A
3.25
3.3
3.35
MODE = unconnected, MAX15062A
3.25
3.35
3.42
MODE = GND, MAX15062B
4.93
5
5.07
MODE = unconnected, MAX15062B
4.93
5.08
5.18
V
nA
OUTPUT VOLTAGE (VOUT)
VOUT Regulation Voltage
VOUT-REG
V
CURRENT LIMIT
Peak Current-Limit Threshold
IPEAK-LIMIT
0.49
0.56
0.62
A
Runaway Current-Limit Threshold
IRUNAWAY-
0.58
0.66
0.73
A
Negative Current-Limit Threshold
ISINK-LIMIT
0.25
0.3
0.35
A
PFM Current Level
LIMIT
MODE = GND
IPFM
0.01
mA
0.13
A
TIMING
Switching Frequency
fSW
465
Events to Hiccup After Crossing
Runaway Current Limit
62.5
Hiccup Timeout
Maximum Duty Cycle
www.maximintegrated.com
535
1
FB/VOUT Undervoltage Trip Level
to Cause Hiccup
Minimum On-Time
500
64.5
Cycles
66.5
131
tON-MIN
DMAX
FB/VOUT = 0.98 x FB/VOUT-REG
89
kHz
%
ms
90
130
ns
91.5
94
%
Maxim Integrated │ 3
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Electrical Characteristics (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, LX = MODE = RESET = unconnected; TA = TJ = -40°C to +125°C, unless
otherwise noted. Typical values are at TA = +25°C. All voltages are referenced to GND, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
LX Dead Time
TYP
MAX
5
UNITS
ns
RESET
FB/VOUT Threshold for RESET
Rising
FB/VOUT rising
93.5
95.5
97.5
%
FB/VOUT Threshold for RESET
Falling
FB/VOUT falling
90
92
94
%
RESET Delay After FB/VOUT
Reaches 95% Regulation
2
ms
RESET Output Level Low
IRESET = 5mA
0.2
V
RESET Output Leakage Current
VRESET = 5.5V, TA = +25°C
0.1
µA
MODE
MODE Internal Pullup Resistor
500
kΩ
166
°C
10
°C
THERMAL SHUTDOWN
Thermal-Shutdown Threshold
Temperature rising
Thermal-Shutdown Hysteresis
Note 2: All the limits are 100% tested at TA = +25°C. Limits over temperature are guaranteed by design.
www.maximintegrated.com
Maxim Integrated │ 4
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristics
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
70
VIN = 36V
50
50
FIGURE 5 APPLICATION
CIRCUIT, PFM MODE
VOUT = 3.3V
VIN = 48V
10
1
40
30
100
10
1
LOAD CURRENT (mA)
toc02b
VIN = 24V
40
EFFICIENCY (%)
EFFICIENCY (%)
80
VIN = 36V
VIN = 48V
VIN = 60V
50
1
FIGURE 8 APPLICATION
CIRCUIT, PFM MODE
VOUT = 12V
10
70
VIN = 24V
60
VIN = 36V
50
VIN = 48V
40
30
20
10
0
100
0
EFFICIENCY vs. LOAD CURRENT
toc04a
50
EFFICIENCY (%)
EFFICIENCY (%)
VIN = 12V
60
VIN = 24V
50
VIN = 36V
30
VIN = 48V
20
FIGURE 7 APPLICATION
CIRCUIT, PWM MODE
VOUT = 2.5V
10
0
50
100
150
200
LOAD CURRENT (mA)
www.maximintegrated.com
10
200
250
300
250
EFFICIENCY vs. LOAD CURRENT
80
70
60
VIN = 36V
50
VIN = 48V
40
30
20
FIGURE 6 APPLICATION
CIRCUIT, PWM MODE
VOUT = 5V
10
0
300
0
50
100
150
200
EFFICIENCY VS. LOAD CURRENT
OUTPUT VOLTAGE
vs. LOAD CURRENT
3.37
toc04b
VIN = 18V
VIN = 24V
60
VIN = 36V
50
40
VIN = 48V
30
VIN = 60V
20
10
50
100
FIGURE 8 APPLICATION
CIRCUIT, PWM MODE
VOUT = 12V
150
200
LOAD CURRENT (mA)
250
300
250
300
FIGURE 5 APPLICATION
CIRCUIT, PFM MODE
3.36
0
VIN = 12V
VIN = 24V
LOAD CURRENT (mA)
70
0
100
LOAD CURRENT (mA)
80
70
40
150
FIGURE 7 APPLICATION
CIRCUIT, PFM MODE
VOUT = 2.5V
90
90
80
0
100
100
VIN = 6V
90
1
100
FIGURE 5 APPLICATION
CIRCUIT, PWM MODE
VOUT = 3.3V
LOAD CURRENT (mA)
100
VIN = 48V
LOAD CURRENT (mA)
80
60
50
20
100
VIN = 12V
90
70
VIN = 24V
VIN = 36V
30
EFFICIENCY vs. LOAD CURRENT
100
VIN = 18V
90
60
LOAD CURRENT (mA)
EFFICIENCY vs. LOAD CURRENT
100
70
40
FIGURE 6 APPLICATION
CIRCUIT, PFM MODE
VOUT = 5V
VIN = 48V
EFFICIENCY (%)
30
VIN = 36V
60
80
OUTPUT VOLTAGE (V)
40
70
VIN = 12V
90
MAX15062 toc04
60
80
VIN = 6V
3.35
MAX15062 toc05
EFFICIENCY (%)
80
VIN = 24V
90
EFFICIENCY (%)
VIN = 24V
VIN = 12V
toc02a
100
MAX15062 toc03
90
EFFICIENCY (%)
MAX15062 toc01
VIN = 12V
EFFICIENCY vs. LOAD CURRENT
EFFICIENCY vs. LOAD CURRENT
100
MAX15062 toc02
EFFICIENCY vs. LOAD CURRENT
100
VIN = 12V, 24V
3.34
3.33
VIN = 36V
3.32
VIN = 48V
3.31
3.30
3.29
0
50
100
150
200
250
300
LOAD CURRENT (mA)
Maxim Integrated │ 5
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
OUTPUT VOLTAGE
vs. LOAD CURRENT
5.04
VIN = 12V, 36V, 48V
5.02
5.00
VIN = 12V
2.51
VIN = 6V,24V
2.50
VIN = 36V
VIN = 48V
2.49
2.48
50
100
150
200
0
LOAD CURRENT (mA)
0.920
toc06c
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
100
VIN = 12V
VIN = 6V, 24V
VIN = 36V
VIN = 48V
0.900
50
100
150
200
VIN = 36V
3.299
250
300
3.297
VIN = 24V
0
50
100
VIN = 12V
150
200
250
20
40
60
TEMPERATURE (°C)
www.maximintegrated.com
VIN = 48V,60V
0
50
80
100 120
100
150
200
250
300
OUTPUT VOLTAGE
vs. LOAD CURRENT
5.003
FIGURE 6 APPLICATION
CIRCUIT, PWM MODE
5.002
5.001
VIN = 48V
5.000
4.999
4.997
300
VIN = 36V
VIN = 12V
0
50
100
VIN = 24V
150
200
250
300
LOAD CURRENT (mA)
5.04
OUTPUT VOLTAGE (V)
FIGURE 5 APPLICATION
CIRCUIT, LOAD = 300mA
0
12.10
4.998
MAX15062 toc09
3.29
-20
VIN = 36V
LOAD CURRENT (mA)
3.30
-40
12.15
12.00
300
3.300
3.31
3.28
VIN = 24V
LOAD CURRENT (mA)
OUTPUT VOLTAGE
vs. TEMPERATURE
3.32
OUTPUT VOLTAGE (V)
250
VIN = 48V
3.301
LOAD CURRENT (mA)
3.27
200
FIGURE 5 APPLICATION
CIRCUIT, PWM MODE
3.298
0
150
OUTPUT VOLTAGE
vs. LOAD CURRENT
3.302
0.915
0.895
50
3.303
PFM MODE
0.905
12.20
LOAD CURRENT (mA)
FEEDBACK VOLTAGE
vs. LOAD CURRENT
0.910
VIN = 18V
12.05
2.47
300
250
12.25
OUTPUT VOLTAGE vs. TEMPERATURE
MAX15062 toc10
0
FIGURE 8 APPLICATION
CIRCUIT, PFM MODE
12.30
OUTPUT VOLTAGE (V)
4.98
2.52
toc06b
MAX15062 toc08
VIN = 24V
FIGURE 7 APPLICATION
CIRCUIT, PFM MODE
2.53
OUTPUT VOLTAGE
vs. LOAD CURRENT
12.35
OUTPUT VOLTAGE (V)
5.06
toc06a
MAX15062 toc07
OUTPUT VOLTAGE (V)
5.08
2.54
OUTPUT VOLTAGE (V)
FIGURE 6 APPLICATION
CIRCUIT, PFM MODE
MAX15062 toc06
5.10
OUTPUT VOLTAGE
vs. LOAD CURRENT
5.02
5.00
4.98
4.96
4.94
FIGURE 6 APPLICATION
CIRCUIT, LOAD = 300mA
-40
-20
0
20
40
60
80
100 120
TEMPERATURE (°C)
Maxim Integrated │ 6
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE
FEEDBACK VOLTAGE
VS. TEMPERATURE
toc10a
NO-LOAD SUPPLY CURRENT (µA)
0.900
0.896
0.892
0.888
0.884
0
20
40
60
80
92
100
120
PFM MODE
5
15
25
35
45
NO-LOAD SUPPLY CURRENT
vs. TEMPERATURE
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX15062 toc12
INPUT VOLTAGE (V)
120
110
100
90
80
6
55
5
4
3
2
1
PFM MODE
-40 -20
0
20
40
60
80
0
100 120
5
45
SWITCH CURRENT LIMIT
vs. INPUT VOLTAGE
1.95
1.80
1.65
600
550
0
20
40
60
80
TEMPERATURE (°C)
100 120
55
SWITCH PEAK CURRENT LIMIT
500
450
400
350
300
SWITCH NEGATIVE CURRENT LIMIT
250
www.maximintegrated.com
35
SHUTDOWN CURRENT
vs. TEMPERATURE
2.10
-20
25
INPUT VOLTAGE (V)
2.25
-40
15
TEMPERATURE (°C)
MAX15062 toc15
70
2.40
SHUTDOWN CURRENT (µA)
94
TEMPERATURE (°C)
MAX15062 toc14
NO-LOAD SUPPLY CURRENT (µA)
-20
130
1.50
96
MAX15062 toc13
-40
140
60
98
90
SHUTDOWN CURRENT (µA)
0.880
SWITCH CURRENT LIMIT (mA)
FEEDBACK VOLTAGE (V)
0.904
MAX15062 toc11
100
0.908
200
5
15
25
35
45
55
INPUT VOLTAGE (V)
Maxim Integrated │ 7
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
450
400
350
SWITCH NEGATIVE CURRENT LIMIT
250
200
-40
-20
20
40
60
80
1.18
1.16
1.14
1.12
FALLING
1.10
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
TEMPERATURE (°C)
SWITCHING FREQUENCY
vs. TEMPERATURE
RESET THRESHOLD
vs. TEMPERATURE
540
520
500
480
460
440
1.20
1.08
100 120
MAX15062 toc18
SWITCHING FREQUENCY (kHz)
560
0
RISING
1.22
98
100 120
MAX15062 toc19
300
MAX15062 toc17
SWITCH PEAK CURRENT LIMIT
500
EN/UVLO THRESHOLD VOLTAGE (V)
550
EN/UVLO THRESHOLD
vs. TEMPERATURE
1.24
97
RESET THRESHOLD (%)
SWITCH CURRENT LIMIT (mA)
600
MAX15062 toc16
SWITCH CURRENT LIMIT
vs. TEMPERATURE
96
RISING
95
94
93
FALLING
92
91
-40
-20
0
20
40
60
80
100 120
90
0
10
20
30
40
50
60
TEMPERATURE (°C)
TEMPERATURE (°C)
LOAD TRANSIENT RESPONSE,
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
LOAD TRANSIENT RESPONSE,
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
MAX15062 toc21
MAX15062 toc20
VOUT (AC)
100mV/div
VOUT (AC)
100mV/div
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
IOUT
100mA/div
IOUT
100mA/div
100µs /div
www.maximintegrated.com
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
100µs /div
Maxim Integrated │ 8
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
LOAD TRANSIENT RESPONSE
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
LOAD TRANSIENT RESPONSE,
PFM MODE (LOAD CURRENT STEPPED
FROM 5mA TO 150mA)
toc21b
toc21a
VOUT (AC)
200mV/div
VOUT (AC)
100mV/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
IOUT
100mA/div
IOUT
100mA/div
100µs/div
100µs/div
LOAD TRANSIENT RESPONSE,
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
LOAD TRANSIENT RESPONSE,
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
MAX15062 toc22
MAX15062 toc23
VOUT (AC)
100mV/div
VOUT (AC)
100mV/div
IOUT
100mA/div
IOUT
100mA/div
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
40µs/div
40µs/div
LOAD TRANSIENT RESPONSE
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
LOAD TRANSIENT RESPONSE
PFM OR PWM MODE (LOAD CURRENT
STEPPED FROM 150mA TO 300mA)
toc23a
VOUT (AC)
50mV/div
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
toc23b
VOUT (AC)
200mV/div
IOUT
100mA/div
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
40µs/div
www.maximintegrated.com
IOUT
100mA/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
40µs/div
Maxim Integrated │ 9
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
LOAD TRANSIENT RESPONSE,
PWM MODE (LOAD CURRENT
STEPPED FROM NO LOAD TO 150mA)
LOAD TRANSIENT RESPONSE,
PWM MODE PWM mode (LOAD CURRENT
STEPPED FROM NO LOAD TO 150mA)
MAX15062 toc24
VOUT (AC)
100mV/div
MAX15062 toc25
VOUT (AC)
100mV/div
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
IOUT
100mA/div
IOUT
100mA/div
40µs/div
40µs/div
LOAD TRANSIENT RESPONSE
PWM MODE (LOAD CURRENT STEPPED
FROM NO LOAD TO 150mA)
LOAD TRANSIENT RESPONSE
PWM MODE (LOAD CURRENT STEPPED
FROM NO LOAD TO 150mA)
toc25b
toc25a
VOUT (AC)
VOUT (AC)
200mV/div
50mV/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
IOUT
100mA/div
IOUT
100mA/div
40µs/div
40µs/div
FULL-LOAD SWITCHING WAVEFORMS
(PWM OR PFM MODE)
SWITCHING WAVEFORMS
(PFM MODE)
MAX15062 toc27
MAX15062 toc26
VOUT (AC)
100mV/div
FIGURE 6 APPLICATION CIRCUIT
VOUT = 5V, LOAD = 20mA
VOUT (AC)
20mV/div
VLX
10V/div
VLX
10V/div
IOUT
200mA/div
IOUT
100mA/div
10µs/div
www.maximintegrated.com
VOUT = 5V,
LOAD = 300mA
2µs/div
Maxim Integrated │ 10
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
NO-LOAD SWITCHING WAVEFORMS
(PWM MODE)
SOFT-START
MAX15062 toc28
VOUT = 5V
MAX15062 toc29
VEN/UVLO
5V/div
VOUT (AC)
20mV/div
VLX
10V/div
VOUT
1V/div
IOUT
100mA/div
IOUT
100mA/div
VRESET
5V/div
2µs/div
SOFT-START
FIGURE 5
APPLICATION CIRCUIT
VOUT = 3.3V
1ms/div
SOFT-START
toc30a
MAX15062 toc30
VEN/UVLO
5V/div
VEN/ UVLO
5V/div
VOUT
1V/div
VOUT
1V/div
IOUT
100mA/div
VRESET
5V/div
IOUT
100mA/div
FIGURE 6
APPLICATION CIRCUIT
VOUT = 5V
VRESET
5V/div
1ms/div
1ms/div
SOFT-START
SHUTDOWN WITH ENABLE
MAX15062 toc31
toc30b
VEN/UVLO
VEN/UVLO
5V/div
5V/div
VOUT
1V/div
VOUT
5V/div
IOUT
100mA/div
IOUT
100mA/div
FIGURE 8
APPLICATION CIRCUIT
VOUT = 12V
VRESET
5V/div
1ms/div
www.maximintegrated.com
FIGURE 7
APPLICATION CIRCUIT
VOUT = 2.5V
VRESET
5V/div
400µs /div
Maxim Integrated │ 11
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Typical Operating Characteristicsc (continued)
(VIN = 24V, VGND = 0V, CIN = CVCC = 1µF, VEN/UVLO = 1.5V, TA = +25°C, unless otherwise noted.)
SOFT-START WITH 3V PREBIAS
OVERLOAD PROTECTION
MAX15062 toc32
MAX15062 toc33
VEN/ UVLO
5V/div
VIN
20V/div
VOUT
1V/div
VOUT
2V/div
FIGURE 6
APPLICATION CIRCUIT
NO LOAD
PWM MODE
IOUT
200mA/div
VRESET
5V/div
1ms/div
144
40
108
30
72
20
10
36
10
0
0
40
GAIN
30
PHASE
20
fCR = 47kHz,
PHASE MARGIN = 59°
-10
-20
FIGURE 5 APPLICATION CIRCUIT
VOUT = 3.3V
-30
-40
-50
-36
2
4 6 81
1k
2
4 6 81
10k
2
100k
GAIN (dB)
50
PHASE (°)
180
BODE PLOT
-108
-30
-144
-40
-180
-50
30
GAIN (dB)
20
PHASE
10
0
FIGURE 7 APPLICATION CIRCUIT
VOUT = 2.5V
-40
-50
1k
10k
FREQUENCY (Hz)
www.maximintegrated.com
144
40
108
30
72
20
36
10
-36
-20
-30
50
0
fCR = 43kHz,
PHASE MARGIN = 60°
-10
180
100k
GAIN (dB)
MAX15062 toc35a
GAIN
40
0
fCR = 47kHz,
PHASE MARGIN = 60°
-36
-72
FIGURE 6 APPLICATION CIRCUIT
VOUT = 5V
2
1k
4 6 81
2
4 6 81
2
100k
10k
-108
-144
-180
FREQUENCY (Hz)
PHASE (°)
BODE PLOT
72
36
FREQUENCY (Hz)
50
108
PHASE
-10
-20
180
144
GAIN
0
-72
MAX15062 toc35
PHASE (°)
MAX15062 toc34
BODE PLOT
-108
-30
-144
-40
-180
-50
108
PHASE
72
36
0
fCR = 36kHz,
PHASE MARGIN = 66°
-10
-20
180
144
GAIN
0
-72
MAX15062 toc35b
-36
PHASE (°)
BODE PLOT
50
GAIN (dB)
20ms/div
-72
FIGURE 8 APPLICATION CIRCUIT
VOUT = 12V
1k
100k
10k
-108
-144
-180
FREQUENCY (Hz)
Maxim Integrated │ 12
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Pin Configuration
TOP VIEW
LX
GND
RESET
MODE
8
7
6
5
MAX15062
+
1
2
3
4
VIN
EN/UVLO
VCC
FB/VOUT
TDFN
(2mm x 2mm)
Pin Description
PIN
NAME
FUNCTION
1
VIN
Switching Regulator Power Input. Connect a X7R 1µF ceramic capacitor from VIN to GND for bypassing.
2
EN/UVLO
Active-High, Enable/Undervoltage-Detection Input. Pull EN/UVLO to GND to disable the regulator output.
Connect EN/UVLO to VIN for always-on operation. Connect a resistor-divider between VIN and EN/UVLO
to GND to program the input voltage at which the device is enabled and turns on.
3
VCC
4
FB/VOUT
5
MODE
PFM/PWM Mode Selection Input. Connect MODE to GND to enable the fixed-frequency PWM operation.
Leave unconnected for light-load PFM operation.
6
RESET
Open-Drain Reset Output. Pull up RESET to an external power supply with an external resistor.
RESET goes low when the output voltage drops below 92% of the set nominal regulated voltage. RESET
goes high impedance 2ms after the output voltage rises above 95% of its regulation value. See the
Electrical Characteristics table for threshold values.
7
GND
Ground. Connect GND to the power ground plane. Connect all the circuit ground connections together at
a single point. See the PCB Layout Guidelines section.
8
LX
Inductor Connection. Connect LX to the switching side of the inductor. LX is high impedance when the
device is in shutdown.
www.maximintegrated.com
Internal LDO Power Output. Bypass VCC to GND with a minimum 1µF capacitor.
Feedback Input. For fixed output voltage versions, connect FB/VOUT directly to the output. For the
adjustable output voltage version, connect FB/VOUT to a resistor-divider between VOUT and GND to
adjust the output voltage from 0.9V to 0.89 x VIN.
Maxim Integrated │ 13
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Block Diagram
VIN
LDO
REGULATOR
PEAK-LIMIT
RUNAWAYCURRENTLIMIT
SENSE
LOGIC
PFM
VCC
MAX15062
CS
CURRENTSENSE
AMPLIFIER
POK
EN/UVLO
DH
CHIPEN
HIGH-SIDE
DRIVER
1.215V
THERMAL
SHUTDOWN
VCC
CLK
LX
OSCILLATOR
SLOPE
500kΩ
MODE
MODE SELECT
0.55VCC
PFM/PWM
CONTROL
LOGIC
DL
LOW-SIDE
DRIVER
SLOPE
CS
FB/VOUT
R1
*
PWM
SINK-LIMIT
ERROR
AMPLIFIER
R2
REFERENCE
SOFT-START
CLK
*RESISTOR-DIVIDER ONLY FOR MAX15062A, MAX15062B
www.maximintegrated.com
LOW-SIDE
CURRENT
SENSE
NEGATIVE
CURRENT
REF
3.135V FOR MAX15062A
4.75V FOR MAX15062B
0.859V FOR MAX15062C
FB/VOUT
GND
RESET
2ms
DELAY
Maxim Integrated │ 14
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Detailed Description
The MAX15062 high-efficiency, high-voltage, synchronous step-down DC-DC converter with integrated
MOSFETs operates over a wide 4.5V to 60V input voltage
range. The converter delivers output current up to 300mA
at 3.3V (MAX15062A), 5V (MAX15062B), and adjustable
output voltages (MAX15062C). When EN/UVLO and
VCC UVLO are satisfied, an internal power-up sequence
soft-starts the error-amplifier reference, resulting in a
clean monotonic output-voltage soft-start independent of
the load current. The FB/VOUT pin monitors the output
voltage through a resistor-divider. RESET transitions
to a high-impedance state 2ms after the output voltage
reaches 95% of regulation. The device selects either
PFM or forced-PWM mode depending on the state of the
MODE pin at power-up. By pulling the EN/UVLO pin to
low, the device enters the shutdown mode and consumes
only 2.2µA (typ) of standby current.
DC-DC Switching Regulator
The device uses an internally compensated, fixed-frequency, current-mode control scheme (see the Block
Diagram). On the rising edge of an internal clock, the
high-side pMOSFET turns on. An internal error amplifier
compares the feedback voltage to a fixed internal reference voltage and generates an error voltage. The error
voltage is compared to a sum of the current-sense voltage
and a slope-compensation voltage by a PWM comparator
to set the on-time. During the on-time of the pMOSFET,
the inductor current ramps up. For the remainder of the
switching period (off-time), the pMOSFET is kept off and
the low-side nMOSFET turns on. During the off-time, the
inductor releases the stored energy as the inductor current
ramps down, providing current to the output. Under overload conditions, the cycle-by-cycle current-limit feature
limits the inductor peak current by turning off the high-side
pMOSFET and turning on the low-side nMOSFET.
Mode Selection (MODE)
The logic state of the MODE pin is latched after VCC
and EN/UVLO voltages exceed respective UVLO rising
thresholds and all internal voltages are ready to allow
LX switching. If the MODE pin is unconnected at powerup, the part operates in PFM mode at light loads. If the
MODE pin is grounded at power-up, the part operates in
constant-frequency PWM mode at all loads. State changes on the MODE pin are ignored during normal operation.
PWM Mode Operation
In PWM mode, the inductor current is allowed to go
negative. PWM operation is useful in frequency sensi-
www.maximintegrated.com
tive applications and provides fixed switching frequency
at all loads. However, the PWM mode of operation gives
lower efficiency at light loads compared to PFM mode of
operation.
PFM Mode Operation
PFM mode operation disables negative inductor
current and additionally skips pulses at light loads for high
efficiency. In PFM mode, the inductor current is forced to
a fixed peak of 130mA every clock cycle until the output
rises to 102.3% of the nominal voltage. Once the output
reaches 102.3% of the nominal voltage, both high-side
and low-side FETs are turned off and the part enters
hibernate operation until the load discharges the output
to 101.1% of the nominal voltage. Most of the internal
blocks are turned off in hibernate operation to save
quiescent current. After the output falls below 101.1%
of the nominal voltage, the device comes out of hibernate operation, turns on all internal blocks, and again
commences the process of delivering pulses of energy
to the output until it reaches 102.3% of the nominal output voltage. The device naturally exits PFM
mode when the load current exceeds 55mA
(typ). The advantage of the PFM mode is higher
efficiency at light loads because of lower quiescent
current drawn from supply.
Internal 5V Linear Regulator
An internal regulator provides a 5V nominal supply to
power the internal functions and to drive the power
MOSFETs. The output of the linear regulator (VCC) should
be bypassed with a 1µF capacitor to GND. The VCC regulator dropout voltage is typically 150mV. An undervoltagelockout circuit that disables the regulator when VCC falls
below 3.8V (typ). The 400mV VCC UVLO hysteresis prevents chattering on power-up and power-down.
Enable Input (EN/UVLO), Soft-Start
When EN/UVLO voltage is above 1.21V (typ), the device’s
internal error-amplifier reference voltage starts to ramp
up. The duration of the soft-start ramp is 4.1ms, allowing a
smooth increase of the output voltage. Driving EN/UVLO
low disables both power MOSFETs, as well as other internal circuitry, and reduces VIN quiescent current to below
2.2µA. EN/UVLO can be used as an input-voltage UVLO
adjustment input. An external voltage-divider between VIN
and EN/UVLO to GND adjusts the input voltage at which
the device turns on or turns off. If input UVLO programming is not desired, connect EN/UVLO to VIN (see the
Electrical Characteristics table for EN/UVLO rising and
falling threshold voltages).
Maxim Integrated │ 15
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Reset Output (RESET)
The device includes an open-drain RESET output to
monitor the output voltage. RESET goes high impedance
2ms after the output rises above 95% of its nominal set
value and pulls low when the output voltage falls below
92% of the set nominal regulated voltage. RESET asserts
low during the hiccup timeout period.
Startup into a Prebiased Output
The device is capable of soft-start into a prebiased output, without discharging the output capacitor in both the
PFM and forced-PWM modes. Such a feature is useful in
applications where digital integrated circuits with multiple
rails are powered.
Operating Input Voltage Range
The maximum operating input voltage is determined by
the minimum controllable on-time and the minimum operating input voltage is determined by the maximum duty
cycle and circuit voltage drops. The minimum and maximum operating input voltages for a given output voltage
should be calculated as follows:
VINMIN
VOUT + (I OUT × (R DCR + 0.5))
+ (I OUT × 1.0)
D MAX
VINMAX =
VOUT
t ONMIN × f SW
where VOUT is the steady-state output voltage, IOUT is
the maximum load current, RDCR is the DC resistance of
the inductor, fSW is the switching frequency (max), DMAX
is maximum duty cycle (0.9), and tONMIN is the worstcase minimum controllable switch on-time (130ns).
Overcurrent Protection/Hiccup Mode
The device is provided with a robust overcurrent
protection scheme that protects the device under overload and output short-circuit conditions. A cycle-by-cycle
peak current limit turns off the high-side MOSFET whenever the high-side switch current exceeds an internal limit
of 0.56A (typ). A runaway current limit on the high-side
switch current at 0.66A (typ) protects the device under
high input voltage, and short-circuit conditions when
there is insufficient output voltage available to restore the
inductor current that was 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
www.maximintegrated.com
to a fault condition, output voltage drops to 65% (typ) of
its nominal value any time after soft-start is complete,
hiccup mode is triggered. In hiccup mode, the converter
is protected by suspending switching for a hiccup timeout
period of 131ms. Once the hiccup timeout period expires,
soft-start is attempted again. Hiccup mode of operation
ensures low power dissipation under output short-circuit
conditions.
Care should be taken in board layout and system wiring
to prevent violation of the absolute maximum rating of the
FB/VOUT pin under short-circuit conditions. Under such
conditions, it is possible for the ceramic output capacitor
to oscillate with the board or wiring inductance between
the output capacitor or short-circuited load, thereby causing the absolute maximum rating of FB/VOUT (-0.3V) to
be exceeded. The parasitic board or wiring inductance
should be minimized and the output voltage waveform
under short-circuit operation should be verified to ensure
the absolute maximum rating of FB/VOUT is not exceeded.
Thermal Overload Protection
Thermal overload protection limits the total power dissipation in the device. When the junction temperature
exceeds +166°C, an on-chip thermal sensor shuts down
the device, turns off the internal power MOSFETs, allowing the device to cool down. The thermal sensor turns the
device on after the junction temperature cools by 10°C.
Applications Information
Inductor Selection
A low-loss inductor having the lowest possible DC resistance that fits in the allotted dimensions should be selected.
The saturation current (ISAT) must be high enough to
ensure that saturation cannot occur below the maximum
current-limit value (IPEAK-LIMIT) of 0.56A (typ). The required
inductance for a given application can be determined from
the following equation:
L = 9.3 x VOUT
where L is inductance in µH and VOUT is output voltage.
Once the L value is known, the next step is to select the
right core material. Ferrite and powdered iron are commonly available core materials. Ferrite cores have low
core losses and are preferred for high-efficiency designs.
Powdered iron cores have more core losses and are relatively cheaper than ferrite cores. See Table 1 to select the
inductors for typical applications.
Maxim Integrated │ 16
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Table 1. Inductor Selection
INPUT VOLTAGE
RANGE VIN (V)
VOUT (V)
IOUT (mA)
L (µH)
4.5 to 60
3.3 (Fixed)
300
33
Coilcraft LPS4018-333ML
6 to 60
5 (Fixed)
300
47
Coilcraft LPS4018-473ML
4.5 to 60
1.8 or 2.5
300
22
Coilcraft LPS4018-223ML
14 to 60
12
300
100
Wurth 74408943101
17 to 60
15
300
150
TDK VLC6045T-151M
RECOMMENDED PART NO.
Table 2. Output Capacitor Selection
INPUT VOLTAGE
RANGE VIN (V)
VOUT (V)
IOUT (mA)
COUT (µF)
4.5 to 60
3.3 (Fixed)
300
10µF/1206/X7R/6.3V
Murata GRM31CR70J106K
RECOMMENDED PART NO.
6 to 60
5 (Fixed)
300
10µF/1206/X7R/6.3V
Murata GRM31CR70J106K
4.5 to 60
1.8 or 2.5
300
22µF/1206/X7R/6.3V
Murata GRM31CR70J226K
14 to 60
12
300
4.7µF/1206/X7R/16V
Murata GRM31CR71C475K
17 to 60
15
300
4.7µF/1206/X7R/25V
Murata GRM31CR71E475K
VIN
VIN
R1
MAX15062
EN/UVLO
R2
conditions and stabilizes the device’s internal control loop.
Usually the output capacitor is sized to support a step
load of 50% of the maximum output current in the application, such that the output-voltage deviation is less than
3%. The device requires a minimum of 10µF capacitance
for stability. Required output capacitance can be calculated from the following equation:
C OUT =
Figure 1. Adjustable EN/UVLO Network
Input Capacitor
Small ceramic capacitors are recommended for the
device. The input capacitor reduces peak current drawn
from the power source and reduces noise and voltage
ripple on the input caused by the switching circuitry. A
minimum of 1µF, X7R-grade capacitor in a package larger
than 0805 is recommended for the input capacitor of the
device to keep the input voltage ripple under 2% of the
minimum input voltage, and to meet the maximum ripplecurrent requirements.
Output Capacitor
Small ceramic X7R-grade capacitors are sufficient and
recommended for the device. The output capacitor has
two functions. It filters the square wave generated by the
device along with the output inductor. It stores sufficient
energy to support the output voltage under load transient
www.maximintegrated.com
30
VOUT
where COUT is the output capacitance in µF and VOUT
is the output voltage. See Table 2 to select the output
capacitor for typical applications.
Setting the Input Undervoltage-Lockout Level
The devices offer an adjustable input undervoltagelockout level. Set the voltage at which the device turns
on with a resistive voltage-divider connected from VIN
to GND (see Figure 1). Connect the center node of the
divider to EN/UVLO.
Choose R1 to be 3.3MΩ max, and then calculate R2 as
follows:
R2 =
R1× 1.215
(VINU - 1.215)
where VINU is the voltage at which the device is required
to turn on.
Maxim Integrated │ 17
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Adjusting the Output Voltage
The MAX15062C output voltage can be programmed
from 0.9V to 0.89 x VIN. Set the output voltage by connecting a resistor-divider from output to FB to GND (see
Figure 2).
For the output voltages less than 6V, choose R2 in the
50kΩ to 150kΩ range. For the output voltages greater
than 6V, choose R2 in the 25kΩ to 75kΩ range and calculate R1 with the following equation:
V
= R2 ×  OUT
R1
 0.9
−

1

Power Dissipation
Ensure that the junction temperature of the device does
not exceed 125°C under the operating conditions specified for the power supply. At a particular operating condition, the power losses that lead to temperature rise of the
part are estimated as follows:

 1 
2
PLOSS =
POUT ×  - 1  - (I OUT × R DCR )
η




PCB Layout Guidelines
Careful PCB layout is critical to achieve clean and stable
operation. The switching power stage requires particular
attention. Follow the guidelines below for good PCB layout.
● Place the input ceramic capacitor as close as possible
to the VIN and GND pins.
● Connect the negative terminal of the VCC bypass
capacitor to the GND pin with shortest possible trace or
ground plane.
● Minimize the area formed by the LX pin and the inductor connection to reduce the radiated EMI.
● Place the VCC decoupling capacitor as close as possible to the VCC pin.
● Ensure that all feedback connections are short and
direct.
● Route the high-speed switching node (LX) away from
the FB/VOUT, RESET, and MODE pins.
For a sample PCB layout that ensures the first-pass
success, refer to the MAX15062 evaluation kit layouts
available at www.maximintegrated.com.
P=
OUT VOUT × I OUT
where POUT is the output power, η is the efficiency of
power conversion, and RDCR is the DC resistance of the
output inductor. See the Typical Operating Characteristics
for the power-conversion efficiency or measure the efficiency to determine the total power dissipation.
The junction temperature (TJ) of the device can be estimated at any ambient temperature (TA) from the following
equation:
VOUT
R1
FB
MAX15062C
R2
GND
TJ= T A + (θ JA × PLOSS )
where θJA is the junction-to-ambient thermal impedance
of the package.
www.maximintegrated.com
Figure 2. Setting the Output Voltage
Maxim Integrated │ 18
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
VIN
VIN
CIN
LX
L1
VOUT
COUT
R1
GND
EN/UVLO
MAX15062A/B
R2
VOUT
VCC
VCC
CVCC
RESET
R3
MODE
VCC
VIN PLANE
CIN
U1
R1
LX
VIN
EN/UVLO
GND
VCC
R2
CVCC
L1
COUT
RESET
VOUT
MODE
R3
VIAS TO BOTTOM-SIDE GROUND PLANE
VIAS TO VOUT
GND
PLANE
VOUT PLANE
VIAS TO VCC
Figure 3. Layout Guidelines for MAX15062A and MAX15062B
www.maximintegrated.com
Maxim Integrated │ 19
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
VIN
VIN
CIN
LX
L1
VOUT
COUT
R1
GND
EN/UVLO
R4
MAX15062C
R2
FB
VCC
R5
VCC
CVCC
RESET
R3
MODE
VCC
VIN PLANE
CIN
U1
R1
LX
VIN
EN/UVLO
GND
VCC
R2
CVCC
L1
COUT
RESET
FB
MODE
GND
PLANE
R5
VOUT PLANE
R4
R3
VIAS TO BOTTOM-SIDE GROUND PLANE
VIAS TO VOUT
VIAS TO VCC
Figure 4. Layout Guidelines for MAX15062C
www.maximintegrated.com
Maxim Integrated │ 20
MAX15062
VIN
4.5V TO
60V
CIN
1µF
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
VIN
EN/UVLO
LX
L1
33µH
COUT
10µF
GND
VOUT
3.3V,
300mA
VIN
6V TO
60V
CIN
1µF
MAX15062A
CVCC
1µF
VCC
MODE
EN/UVLO
LX
COUT
10µF
GND
RESET
CVCC
1µF
VOUT
VCC
MODE
RESET
VOUT
MODE = GND FOR PWM
MODE = OPEN FOR PFM
MODE = GND FOR PWM
MODE = OPEN FOR PFM
L1: COILCRAFT LPS4018-333ML
COUT: MURATA 10µF/X7R/6.3V/1206 GRM31CR70J106K
CIN: MURATA 1µF/X7R/100V/1206 GRM31CR72A105K
L1: COILCRAFT LPS4018-473ML
COUT: MURATA 10µF/X7R/6.3V/1206 GRM31CR70J106K
CIN: MURATA 1µF/X7R/100V/1206 GRM31CR72A105K
CIN
1µF
VIN
EN/UVLO
LX
Figure 6. 5V, 300mA Step-Down Regulator
L1
22µH
GND
MAX15062C
CVCC
1µF
VCC
MODE
COUT
22µF
VOUT
2.5V,
300mA
CIN
1µF
R1
133kΩ
FB
RESET
VIN
14V TO
60V
EN/UVLO
LX
COUT
4.7µF
GND
VCC
MODE
FB
R2
40.2kΩ
RESET
MODE = GND FOR PWM
MODE = OPEN FOR PFM
L1: COILCRAFT LPS4018-223ML
COUT: MURATA 22µF/X7R/6.3V/1206 (GRM31CR70J226K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
L1: Wurth 74408943101
COUT: MURATA 4.7µF/X7R/16V/1206 (GRM31CR71C475K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
Figure 7. 2.5V, 300mA Step-Down Regulator
VOUT
12V,
300mA
R1
499kΩ
MAX15062C
CVCC
1µF
R2
75kΩ
VIN
L1
100µH
MODE = GND FOR PWM
MODE = OPEN FOR PFM
www.maximintegrated.com
VOUT
5V,
300mA
MAX15062B
Figure 5. 3.3V, 300mA Step-Down Regulator
VIN
4.5V TO
60V
VIN
L1
47µH
Figure 8. 12V, 300mA Step-Down Regulator
Maxim Integrated │ 21
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Ordering Information
VIN
4.5V TO
60V
CIN
1µF
VIN
EN/UVLO
LX
L1
22µH
COUT
22µF
GND
R1
75kΩ
MAX15062C
CVCC
1µF
R2
75kΩ
RESET
L1: COILCRAFT LPS4018-223ML
COUT: MURATA 22µF/X7R/6.3V/1206 (GRM31CR70J226K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
CIN
1µF
EN/UVLO
VCC
MODE
MAX15062AATA+
-40°C to +125°C
8 TDFN
3.3V
MAX15062BATA+
-40°C to +125°C
8 TDFN
5V
MAX15062CATA+
-40°C to +125°C
8 TDFN
Adj
Chip Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.com/packages. Note
that a “+”, “#”, or “-” in the package code indicates RoHS status
only. Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
LX
L1
150µH
GND
MAX15062C
CVCC
1µF
VOUT
Package Information
Figure 9. 1.8V, 300mA Step-Down Regulator
VIN
PINPACKAGE
PROCESS: BiCMOS
MODE = GND FOR PWM
MODE = OPEN FOR PFM
VIN
17V TO
60V
TEMP RANGE
PART
+Denotes a lead(Pb)-free/RoHS-compliant package.
FB
VCC
MODE
VOUT
1.8V,
300mA
COUT
4.7µF
VOUT
15V,
300mA
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
8 TDFN
T822CN+1
21-0487
90-0349
R1
499kΩ
FB
RESET
R2
31.6kΩ
MODE = GND FOR PWM
MODE = OPEN FOR PFM
L1: TDK VLC6045T-151M
COUT: MURATA 4.7µF/X7R/25V/1206 (GRM31CR71E475K)
CIN: MURATA 1µF/X7R/100V/1206 (GRM31CR72A105K)
Figure 10. 15V, 300mA Step-Down Regulator
www.maximintegrated.com
Maxim Integrated │ 22
MAX15062
60V, 300mA, Ultra-Small, High-Efficiency,
Synchronous Step-Down DC-DC Converters
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
6/13
Initial release
1
10/13
Added MAX15062C, added figures, updated tables and figures throughout
—
1–17
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.
© 2013 Maxim Integrated Products, Inc. │ 23