请登录

免费注册
全部商品
电子元器件
方案中心
工业品
PDF资料

产品分类

找货询价

一对一服务 找料无忧

专属客服

服务时间

周一至周六 8:30-17:30

QQ咨询

一对一服务 找料无忧

专属客服：823711899

服务时间

周一至周六 8:30-17:30

会员中心
购物车
技术支持

一对一服务 找料无忧

专属客服

服务时间

周一至周六 8:30-17:30

售后咨询

一对一服务 找料无忧

专属客服

服务时间

周一至周六 8:30-17:30

MAX20058

型号：

MAX20058

品牌：

MAXIM[ MAXIM INTEGRATED PRODUCTS ]

页数：

17 页

PDF大小：

713 K

下载PDF手册
EVALUATION KIT AVAILABLE  
Click here for production status of specific part numbers.  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
General Description  
Benefits and Features  
● Synchronous DC-DC Converters with Integrated FETs  
• 60V Input for 14V and 24V Systems  
• Internal Compensation  
The MAX20058 is a high-efficiency, high-voltage, syn-  
chronous step-down DC-DC converter IC with integrated  
MOSFETs that operates over a 4.5V to 60V input. The  
converters can deliver up to 1A current. Output voltage is  
programmable from 0.8V to 90%V . The feedback volt-  
age-regulation accuracy over -40°C to +125°C is ±1.5%.  
● Flexibility  
IN  
• Output Adjustable from 0.8V to 90%V  
• 200kHz to 2200kHz Adjustable Frequency with  
External Clock Synchronization  
IN  
The IC features a peak-current-mode-control architecture  
and can be operated in the pulse-width modulation (PWM)  
or pulse-frequency modulation (PFM) control schemes.  
• Programmable Peak Current Limit (1.14A or 1.6A)  
●
RESET Output and EN Input (26V max) Simplify  
Power Sequencing  
The MAX20058 is available in a 12-pin (3mm x 3mm)  
side-wettable TDFN package with an exposed pad for  
thermal heat dissipation.  
● Protection Features and Operating Range Ideal for  
Automotive Applications  
• Programmable EN/UVLO Threshold  
• Adjustable Soft-Start and Prebiased Power-Up  
• Thermal Shutdown  
• -40°C to +125°C Automotive Temperature Range  
• AEC-Q100 Qualified  
Applications  
● 14V/24V Systems  
● Truck Applications  
Ordering Information appears at end of data sheet.  
19-100263; Rev 2; 5/19  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Absolute Maximum Ratings  
V
to SGND .........................................................-0.3V to +65V  
Continuous Power Dissipation  
IN  
EN/UVLO to SGND...............................................-0.3V to +26V  
(Multilayer Board) (T = +70°C,  
A
EXTVCC to SGND ................................................-0.3V to +14V  
LX to PGND..................................................-0.3V to V + 0.3V  
IN  
FB, SS, MODE/ILIM,  
derate 24.4mW/°C above +70°C)...........................1951.2mW  
Operating Temperature Range......................... -40°C to +125°C  
Junction Temperature......................................................+150°C  
Storage Temperature Range............................ -65°C to +150°C  
Lead Temperature (soldering, 10s) .................................+300°C  
Soldering Temperature (reflow).......................................+260°C  
ESD Protection – Human Body Model................................±2kV  
RT/SYNC to SGND .................................-0.3V to V  
+ 0.3V  
CC  
PGND to SGND....................................................-0.3V to +0.3V  
LX Total RMS Current ........................................................±1.2A  
RESET, V  
to SGND............................................-0.3V to +6V  
CC  
Package Information  
12 SW TDFN-EP  
Package Code  
TD1233Y+2  
21-100176  
90-100072  
Outline Number  
Land Pattern Number  
Thermal Resistance, Four-Layer Board:  
Junction to Ambient (θ  
)
41°C/W  
8.5°C/W  
JA  
Junction to Case (θ  
)
JC  
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.  
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.  
Maxim Integrated  
│ 2  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Electrical Characteristics  
(V = 24V, V  
= unconnected, R  
= 105kΩ, LX = unconnected, T = T = -40°C to +125°C, unless otherwise noted.  
RT A J  
IN  
EN/UVLO  
(Note 1)  
PARAMETER  
Input Voltage Range  
Input Shutdown Current  
SYMBOL  
CONDITIONS  
MIN  
4.5  
TYP  
MAX  
60  
UNITS  
V
V
IN  
I
V
= 0V, shutdown mode  
2.5  
5
90  
4
13  
µA  
IN-SH  
EN  
I
R
R
= open or 422kΩ  
= 243kΩ or 121kΩ  
µA  
Q_PFM  
ILIM  
ILIM  
Input Quiescent Current  
I
3
5
mA  
Q_PWM  
ENABLE/UVLO (EN)  
V
V
V
V
V
rising  
1.19  
1.09  
1.215  
1.115  
0.7  
1.24  
1.14  
ENR  
EN/UVLO  
EN/UVLO  
EN/UVLO  
EN/UVLO  
EN Threshold  
V
falling  
V
ENF  
V
falling, true shutdown  
= 1.215V  
EN-TRUESD  
EN Pullup Current  
I
2.2  
2.5  
2.8  
µA  
EN  
LDO (V  
)
CC  
Output Voltage Range  
Current Limit  
VCC  
6V < V < 60V, 0mA < I  
< 5mA  
4.75  
12  
5
5.25  
52  
V
mA  
V
IN  
VCC  
I
V
V
V
V
= 4.3V, V = 12V  
26  
VCC-MAX  
CC  
IN  
Dropout  
V
= 4.5V, I = 5mA  
VCC  
0.3  
CC-DO  
IN  
V
rising  
falling  
4.05  
3.65  
4.2  
3.8  
4.35  
3.95  
V
CC-UVR  
CC  
CC  
UVLO  
V
V
CC-UVF  
EXT LDO (EXTVCC)  
Switchover Threshold  
EXTVCC rising  
4.65  
4.74  
0.3  
4.88  
V
V
Switchover-Threshold  
Hysteresis  
Dropout  
EXTVCC-DO  
V
V
= 4.75V, I  
= 5mA  
0.1  
34  
V
EXTVCC  
VCC  
Current Limit  
POWER MOSFETs  
= 4.3V, V  
= 5V  
15  
21  
mA  
CC  
EXTVCC  
High-Side pMOS  
On-Resistance  
R
I
I
= 0.3A, sourcing  
0.9  
1.8  
Ω
DS-ONH  
LX  
LX  
Low-Side nMOS  
On-Resistance  
R
= 0.3A, sinking  
0.275  
0.55  
2
Ω
DS-ONL  
T = +25°C  
µA  
LX Leakage Current  
SOFT-START  
A
Charging Current  
I
4.7  
5
5.3  
µA  
SS  
Maxim Integrated  
│ 3  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Electrical Characteristics (continued)  
(V = 24V, V  
= unconnected, R  
= 105kΩ, LX = unconnected, T = T = -40°C to +125°C, unless otherwise noted.  
IN  
EN/UVLO  
RT A J  
(Note 1)  
PARAMETER  
FEEDBACK (FB)  
SYMBOL  
CONDITIONS  
MIN  
TYP  
MAX  
UNITS  
R
R
= 243kΩ or 121kΩ  
= open or 422kΩ  
0.788  
0.788  
-100  
0.8  
0.812  
0.824  
100  
V
V
ILIM  
FB Regulation Voltage  
V
FB  
0.812  
ILIM  
FB Input Leakage Current  
V
FB  
= 1V, T = +25°C  
nA  
A
CURRENT LIMIT  
R
R
R
R
R
R
R
= open or 243kW  
= 121kΩ or 422kΩ  
= open or 422kΩ  
= 243kΩ  
1.4  
1.6  
1.14  
2.5  
2.0  
ILIM  
ILIM  
ILIM  
ILIM  
ILIM  
ILIM  
ILIM  
I
SOURCE-  
LIMIT  
Peak Current-Limit Threshold  
A
mA  
A
0.94  
1.36  
Negative Current-Limit  
Threshold  
I
0.57  
0.35  
0.65  
0.455  
0.33  
0.23  
0.725  
0.56  
0.44  
0.32  
SINK-LIMIT  
IPFM  
= 121kΩ  
= open  
0.235  
0.125  
PFM Current Level  
A
= 422kΩ  
MODE  
MODE PFM Threshold  
Hysteresis  
Rising  
1
1.22  
0.19  
1.44  
V
V
TIMINGS  
Minimum On-Time  
Maximum Duty Cycle  
OSCILLATOR  
t
45  
89  
70  
93  
120  
97  
ns  
%
ON-MIN  
DMAX  
R
R
R
R
R
= 210kΩ  
= 140kΩ  
= 105kΩ  
= 69.8kΩ  
= 19.1kΩ  
180  
270  
200  
300  
220  
330  
RT  
RT  
RT  
RT  
RT  
kHz  
Switching Frequency  
f
360  
400  
440  
SW  
540  
600  
660  
1800  
1.15 x  
2033  
2200  
1.4 x  
f
SW  
SYNC Input Frequency  
kHz  
kHz  
ns  
per R  
f
RT  
SW  
SYNC Input Frequency Range  
220  
40  
1
2200  
SYNC Pulse Minimum  
Off-Time  
SYNC pulse must exceed this number  
SYNC High Threshold  
SYNC Hysteresis  
V
1.22  
0.18  
1.44  
V
V
SYNC-H  
V
SYNC-HYS  
Number of SYNC Pulses to  
Enable Synchronization  
(Note 2)  
1
Cycle  
Maxim Integrated  
│ 4  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Electrical Characteristics (continued)  
(V = 24V, V  
= unconnected, R  
= 105kΩ, LX = unconnected, T = T = -40°C to +125°C, unless otherwise noted.  
IN  
EN/UVLO  
RT A J  
(Note 1)  
PARAMETER  
SYMBOL  
CONDITIONS  
MIN  
TYP  
MAX  
UNITS  
RESET  
UV Threshold Rising  
V
V
rising  
falling  
95  
92  
%
%
FB  
FB  
UV Threshold Falling  
Delay after FB reaches 95%  
regulation  
2.1  
ms  
Output Low Level  
I
= 1mA  
0.09  
1
V
RESET  
Output Leakage Current  
THERMAL SHUTDOWN  
Thermal-Shutdown Threshold  
Hysteresis  
T
= +25°C  
µA  
A
Temperature rising (Note 2)  
(Note 2)  
160  
20  
°C  
°C  
Note 1: All limits are 100% tested at +25°C. Limits over the operating temperature range and relevant supply voltage range are  
guaranteed by design and characterization. Typical values are at T = +25°C.  
A
Note 2: Guaranteed by design, not production tested.  
Maxim Integrated  
│ 5  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Typical Operating Characteristics  
(T = +25°C, unless otherwise noted.)  
A
24VIN 400kHz EFFICIENCY  
vs. LOAD CURRENT  
24VIN 2.2MHz EFFICIENCY  
vs. LOAD CURRENT  
toc01  
toc02  
100%  
100%  
90%  
80%  
90%  
80%  
70%  
60%  
50%  
40%  
30%  
20%  
10%  
0%  
70%  
FPWM  
FPWM  
60%  
50%  
40%  
30%  
20%  
10%  
0%  
PFM  
PFM  
fSW = 400kHz  
VIN = 24V  
VOUT = 5V  
fSW = 2.2MHz  
VIN = 24V  
VOUT = 5V  
L = 33µH  
L = 5.6µH  
COUT = 22  
µF  
COUT = 22  
µ
F
TA = +25°C  
0.1  
TA = +25°C  
0.1  
0.0001  
0.001  
0.01  
1
0.0001  
0.001  
0.01  
1
LOAD CURRENT (A)  
LOAD CURRENT (A)  
SHUTDOWN CURRENT  
vs. SUPPLY VOLTAGE  
LINE REGULATION  
(400kHz)  
toc03  
toc04  
5.5  
5.4  
5.3  
5.2  
5.1  
5.0  
4.9  
4.8  
4.7  
4.6  
4.5  
25  
20  
15  
10  
5
EXTERNAL  
COMPONENTS  
REMOVED  
PFM 1mA  
V
EN = 0V  
TA = +125°C  
PFM 1A  
FPWM 1A  
PFM 500mA  
FPWM 500mA  
FPWM 1mA  
TA = +25°C  
L = 33  
COUT = 22  
µ
H
µF  
TA = +25°C  
0
10  
20  
30  
40  
50  
60  
22 26 30 34 38 42 46 50 54 58  
VIN (V)  
VIN (V)  
24VIN 2.2MHz  
LOAD REGULATION  
24VIN 400kHz  
LOAD REGULATION  
toc05  
toc06  
5.20  
5.15  
5.10  
5.05  
5.00  
4.95  
4.90  
5.20  
5.15  
5.10  
5.05  
5.00  
4.95  
4.90  
VIN = 24V  
L = 5.6µH  
VIN = 24V  
L = 33  
COUT = 22  
µ
H
COUT = 22µF  
µF  
PFM +25°C  
PFM +105°C  
PFM +125°C  
PFM +25°C  
PFM +125°C  
PFM +105°C  
FPWM +105°C  
FPWM +25°C  
FPWM +125°C  
FPWM +25°C  
FPWM +125°C  
FPWM +105°C  
0.0  
0.2  
0.4  
0.6  
0.8  
1.0  
0.0  
0.2  
0.4  
0.6  
0.8  
1.0  
LOAD (A)  
LOAD (A)  
Maxim Integrated  
│ 6  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Typical Operating Characteristics (continued)  
(T = +25°C, unless otherwise noted.)  
A
APPLICATION OF EXTERNAL CLOCK  
REMOVAL OF EXTERNAL CLOCK  
5V OUTPUT, 24V INPUT  
5V OUTPUT, 24V INPUT  
FPWM 400kHz to 500kHz  
500kHz to 400kHz FPWM  
toc7  
toc8  
VLX  
VLX  
20V/div  
5V/div  
20V/div  
5V/div  
VOUT  
ILX  
VOUT  
ILX  
500mA/div  
2V/div  
500mA/div  
2V/div  
VSYNC  
VSYNC  
4µs  
4µs  
LOAD TRANSIENT  
FPWM MODE  
LOAD TRANSIENT  
PFM MODE  
(10mA to 1A PULSE)  
(10mA to 1A PULSE)  
toc9  
toc10  
VIN = 24V  
VOUT = 5V  
L = 33  
COUT = 22  
VIN = 24V  
VOUT = 5V  
L = 33  
COUT = 22  
µ
H
µ
H
µF  
µF  
VOUT  
(AC)  
VOUT  
(AC)  
500mV/div  
500mV/div  
2V/div  
1A/div  
2V/div  
1A/div  
IOUT  
IOUT  
VRESET  
VRESET  
1ms  
1ms  
LINE TRANSIENT  
FPWM MODE  
SOFT-START/SHUTDOWN FROM EN  
FPWM MODE  
(10mA LOAD)  
(500mA LOAD)  
toc11  
toc12  
VIN = 24V  
L = 33µH  
COUT = 22µF  
20V/div  
2V/div  
VEN  
VOUT  
ILX  
VIN  
500mV/div  
VOUT  
5V/div  
VIN = 24V  
L = 33  
COUT = 22  
µ
H
500mA/div  
µF  
5V/div  
VRESET  
5V/div  
VRESET  
200µs  
2ms  
Maxim Integrated  
│ 7  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Typical Operating Characteristics (continued)  
(T = +25°C, unless otherwise noted.)  
A
SHORT-CIRCUIT  
FPWM MODE  
SOFT-SHORT CIRCUIT  
(VOUT FORCED TO 80% OF REGULATION)  
toc13  
toc14  
20V/div  
VLX  
VOUT  
ILX  
20V/div  
5V/div  
VLX  
VOUT  
ILX  
5V/div  
1A/div  
1A/div  
5V/div  
VRESET  
5V/div  
VRESET  
20µs  
20µs  
STEADY-STATE SWITCHING WAVEFORMS  
(5V OUTPUT, 1A LOAD CURRENT)  
STEADY-STATE SWITCHING WAVEFORMS  
(5V OUTPUT, 10mA LOAD CURRENT)  
PFM MODE  
FPWM MODE  
toc15  
toc16  
VOUT  
(AC)  
VOUT  
(AC)  
20mV/div  
50mV/div  
20V/div  
VLX  
ILX  
500mA/div  
VLX  
10V/div  
1µs  
40µs  
SLOW INPUT VOLTAGE  
(5V OUTPUT, 10mA LOAD CURRENT)  
PFM MODE  
toc17  
20V/div  
VIN  
VOUT  
2V/div  
5V/div  
VRESET  
4s  
Maxim Integrated  
│ 8  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Pin Configuration  
TOP VIEW  
12  
11 10  
9
8
7
MAX20058  
+
1
2
3
4
5
6
SW TDFN-EP  
(3mm x 3mm)  
Pin Description  
PIN  
NAME  
FUNCTION  
Power Ground Pin of the Converter. Connect externally to the power ground plane. Connect the  
SGND and PGND pins together at the ground return path of the V bypass capacitor.  
1
PGND  
CC  
Power-Supply Input. 4.5V to 60V input supply range. Decouple to PGND with a 2.2µF capacitor;  
place the capacitor close to the V and PGND pins.  
2
3
V
IN  
IN  
5V LDO Output. Bypass V  
with a 1µF ceramic capacitance to SGND. This LDO is intended to  
CC  
V
CC  
power internal circuits only.  
Enable/Undervoltage Lockout Pin. Drive EN/UVLO high to enable the output. Connect to the center of  
4
5
6
EN/UVLO  
RESET  
the resistor-divider between V and SGND to set the input voltage at which the part turns on. Leave  
IN  
the pin unconnected for always-on operation.  
Open-Drain RESET Output. The RESET output is driven low if FB drops below 92% of its set value.  
RESET goes high 2.1ms after FB rises above 95% of its set value.  
Frequency-Set and Synchronization Pin. Connect a resistor from RT/SYNC to SGND to set the  
switching frequency of the part between 200kHz and 2000kHz. An external clock can be connected to  
the RT/SYNC pin to synchronize the part with an external frequency up to 2200kHz.  
RT/SYNC  
7
8
9
EXTVCC  
FB  
External Power-Supply Input for the Internal LDO  
Feedback Input. Connect FB to the center tap of an external resistor-divider from the output to SGND  
to set the output voltage.  
SS  
Soft-Start Input. Connect a capacitor from SS to SGND to set the soft-start time.  
Mode and Current-Limit Set Pin. Connect a resistor from MODE/ILIM to SGND to program the peak  
and runaway current limits and mode of operation of the part. See the Current Limit and Mode of  
Operation Selection section for more details.  
10  
MODE/ILIM  
11  
12  
SGND  
LX  
Analog Ground  
Switching Node. Connect the LX pin to the switching side of the inductor.  
Exposed Pad. Connect EP to the SGND pin. Connect to a large copper plane below the IC to improve  
heat-dissipation capability. Add thermal vias below the exposed pad.  
—
EP  
Maxim Integrated  
│ 9  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Functional Diagram  
EXTVCC  
V
V
IN  
MAX20058  
CC  
INTERNAL LDO  
REGULATORS  
POK  
VCC_INT  
EN/UVLO  
PEAK-LIMIT  
CHIPEN  
CS  
CURRENT-SENSE  
AMPLIFIER  
CURRENT-  
SENSE LOGIC  
1.215V  
PFM  
SGND  
EP  
HIGH-SIDE  
DRIVER  
THERMAL  
SHUTDOWN  
DH  
DL  
LX  
PFM/PWM  
CONTROL  
LOGIC  
LOW-SIDE  
DRIVER  
CLK  
RT/SYNC  
OSCILLATOR  
SLOPE  
PGND  
MODE/ILIM  
MODE SELECT  
SINK LIMIT  
ZX/ILIMN  
COMP  
1.22V  
SLOPE  
CS  
NEGATIVE  
CURRENT REF  
RESET  
FB  
SS  
PWM  
ERROR  
AMPLIFIER  
0.76V  
FB  
2ms  
DELAY  
EXTERNAL  
SOFT-START  
CONTROL  
CLK  
Maxim Integrated  
│ 10  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
PWM Mode Operation  
Detailed Description  
In PWM mode, the inductor current can go negative.  
PWM operation provides constant frequency operation at  
all loads, and is useful in applications sensitive to switch-  
ing frequency. However, the PWM mode of operation  
gives lower efficiency at light loads compared to the PFM  
mode of operation.  
The MAX20058 high-efficiency, high-voltage, step-down  
DC-DC regulator IC operates from 4.5V to 60V and deliv-  
ers up to 1A load current. Feedback voltage-regulation  
accuracy meets ±1.5% over load, line, and temperature.  
The IC 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.  
PFM Mode Operation  
PFM mode of operation disables negative inductor cur-  
rent and additionally skips pulses at light loads for high  
efficiency. In PFM mode, the inductor current is forced  
to a fixed peak every clock cycle until the output rises to  
102% of the nominal voltage by monitoring the FB pin.  
Resistor tolerance will impact actual output voltage. Once  
the output reaches 102% of the nominal voltage, both the  
high-side and low-side FETs are turned off and the device  
enters hibernate operation until the load discharges the  
output to 101% of the nominal voltage. Most of the inter-  
nal blocks are turned off in hibernate operation to save  
quiescent current. After the output falls below 101% of  
the nominal voltage, the device comes out of hibernate  
operation, turns on all internal blocks and again com-  
mences the process of delivering pulses of energy to the  
output until it reaches 102% of the nominal output voltage.  
At each rising edge of the clock, the high-side MOSFET  
turns on and remains on until either the appropriate or  
maximum duty cycle is reached, or the peak current limit  
is detected.  
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  
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 output.  
The internal low R  
pMOS/nMOS switches ensure  
DS(ON)  
high efficiency at full load.  
The IC also integrates switching-frequency selector pin,  
current-limit and mode-of-operation selector pin, enable/  
undervoltage lockout (EN/UVLO) pin, programmable soft-  
start pin, and open-drain RESET signal.  
The advantage of the PFM mode is higher efficiency at  
light loads because of lower quiescent current drawn  
from supply. However, the output-voltage ripple is higher  
compared to PWM mode of operation and switching fre-  
quency is not constant at light loads.  
Current Limit and Mode of Operation  
Table 1 lists the value of the resistors to program PWM or  
PFM modes of operation and 1.6A or 1.14A peak current  
limits.  
Linear Regulator (V  
)
CC  
The IC has two internal low-dropout regulators (LDOs),  
which power V . One LDO is powered from the input  
CC  
The mode of operation cannot be changed “on-the-fly”  
after power-up.  
voltage and the other LDO is powered from the EXTVCC  
pin. Only one of the two LDOs is in operation at a time,  
depending on the voltage levels present at the EXTVCC  
pin.  
Table 1. R  
Settings  
ILIM  
PEAK CURRENT  
LIMIT (A)  
MODE OF  
OPERATION  
If EXTVCC rises above 4.74V (typ), V  
the EXTVCC pin. If EXTVCC falls below 4.44V (typ), V  
is powered from the input voltage. Powering V  
is powered from  
R
(kΩ)  
CC  
ILIM  
CC  
Open  
1.6  
1.14  
1.6  
PFM  
PFM  
PWM  
PWM  
from  
CC  
EXTVCC increases efficiency, particularly at higher input  
voltages. Typical V output voltage is 5V. Bypass V  
422  
243  
121  
CC  
CC  
to SGND with a 1μF capacitor.  
1.14  
When V falls below its undervoltage lockout (3.8V,  
CC  
typ), the internal step-down controller is turned off, and  
LX switching is disabled. The LX switching is enabled  
again when the V  
voltage exceeds 4.2V (typ). The  
CC  
400mV (typ) hysteresis prevents chattering on power-up  
and power-down.  
Maxim Integrated  
│ 11  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
When powering EXTVCC from V  
, a R-C network  
Table 2. RT/SYNC Resistor Settings  
OUT  
should be placed in the path to protect the LDO from a  
potential negative voltage transient due to a short circuit  
event. A 4.7Ω resistor and a 0.1μF capacitor is recom-  
mended (see Typical Application Circuit on page 15).  
RT/SYNC RESISTOR  
SWITCHING FREQUENCY  
(kHz)  
VALUE (kΩ)  
210  
140  
105  
69.8  
19.1  
200  
300  
400  
600  
2000  
Switching-Frequency Selection and External  
Frequency Synchronization  
The RT/SYNC pin programs the switching frequency of  
the converter. Connect a resistor from RT/SYNC to SGND  
to set the switching frequency of the part at any one of five  
discrete frequencies: 200kHz, 300kHz, 400kHz, 600kHz,  
or 2MHz (see Table 2 for resistor values).  
Overcurrent Protection  
The IC is provided with a robust overcurrent-protection  
scheme that protects the device under overload and  
output short-circuit conditions. The positive current limit  
is triggered when the peak value of the inductor current  
hits a fixed threshold (ILIM_P, 1.6A/1.14A). At this point,  
the high-side switch is turned off and the low-side switch  
turned on. The low-side switch is kept on until the inductor  
current discharges below 0.7 x ILIM_P.  
The internal oscillator of the device can be synchro-  
nized to an external clock signal on the RT/SYNC pin.  
The external synchronization clock frequency must be  
between 1.15 x f  
and 1.4 x f , where f  
is the  
SW  
SW  
SW  
frequency programmed by the resistor connected from  
the RT/SYNC pin. The MAX20058 have been tested up  
to 2000kHz with a 19.1kΩ resistor.  
Operating Input Voltage Range  
While in PWM mode of operation, the negative current  
limit is triggered when the valley value of the inductor  
current hits a fixed threshold (ILIM_N, -0.65A/-0.455A,  
depending on the value of the resistor connected to the  
MODE/ILIM pin). At this point, the low-side switch is  
turned off and the high-side switch is turned on.  
The minimum and maximum operating input voltages for  
a given output voltage should be calculated as shown in  
the following equation.  
Equation 1:  
V
+ I  
× (R  
+ 0.55)  
(
)
OUT  
OUT(MAX)  
DCR  
RESET Output  
V
=
+ I  
(
×1.25  
OUT(MAX)  
)
IN(MIN)  
D
MAX  
The IC includes a RESET pin to monitor the output volt-  
age. The open-drain RESET output requires an external  
pullup resistor. RESET goes high (high impedance) in  
2.1ms after the output voltage increases above 95% of  
the nominal voltage. RESET goes low when the output  
voltage drops to below 92% of the nominal voltage.  
RESET also goes low during thermal shutdown.  
V
OUT  
× t  
ON(MIN)  
V
=
IN(MAX)  
f
SW(MAX)  
where V  
is the steady-state output voltage, I  
OUT(MAX)  
OUT  
is the maximum load current, R  
of the inductor, D  
is the DC resistance  
DCR  
is the maximum allowable duty ratio  
is the maximum switching frequency,  
MAX  
(0.89), f  
SW(MAX)  
and t  
(120ns).  
is the worst-case minimum switch on-time  
ON(MIN)  
Thermal-Shutdown Protection  
The IC features thermal-overload protection and turns  
off when the junction temperature exceeds +160°C (typ).  
Once the device cools by 20°C (typ), it turns back on with  
a soft-start sequence.  
Maxim Integrated  
│ 12  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
where:  
and:  
Applications Information  
(V − V  
)× V  
OUT  
×L  
IN  
OUT  
∆I  
=
P−P  
Inductor Selection  
V
× f  
IN SW  
Three key inductor parameters must be specified for  
operation with the device: inductance value (L), inductor  
saturation current (ISAT) and DC resistance (RDCR). To  
select inductor value, the ratio of inductor peak-to-peak  
AC current to DC average current (LIR) must be selected  
first. A good compromise between size and loss is a  
30% peak-to-peak ripple current to average-current ratio  
(LIR = 0.3). The switching frequency, input voltage, output  
voltage, and selected LIR then determine the inductor  
value as follows:  
V
OUT  
D =  
V
IN  
where I  
is the output current, D is the duty cycle,  
is the switching frequency. Use additional input  
OUT  
and f  
SW  
capacitance at lower input voltages to avoid possible  
undershoot below the UVLO threshold during transient  
loading.  
(V –V  
) x V  
OUT  
IN  
OUT  
OUT  
Output Capacitor  
L =  
V
× f  
×I  
×LIR  
IN  
SW  
For optimal phase margin, a 22μF output capacitor is  
recommended. Additional output capacitance may be  
needed based on application-specific output-voltage-  
ripple requirements. If the total output capacitance  
required is > 70μF, contact the factory for an optimized  
solution.  
where V  
, I  
, and f  
are nominal values.  
OUT OUT  
SW  
Select a low-loss inductor closest to the calculated value  
with acceptable dimensions and the lowest possible DC  
resistance. The saturation current rating (ISAT) of the  
inductor must be high enough to ensure that saturation  
occurs only above the peak current-limit value.  
The allowable output-voltage ripple and the maximum  
deviation of the output voltage during step-load currents  
determine the output capacitance and its ESR.  
Input Capacitor Selection  
A low-ESR ceramic input capacitor of 4.7μF is recommend-  
ed for proper device operation. This value can be adjusted  
based on application input-voltage-ripple requirements.  
V
Ripple Requirement  
OUT  
The output ripple comprises ΔV (caused by the capacitor  
Q
discharge) and ΔV  
(caused by the ESR of the output  
ESR  
The discontinuous input current of the buck converter  
causes large input ripple current. The switching frequen-  
cy, peak inductor current, and the allowable peak-to-peak  
input-voltage ripple dictate the input-capacitance require-  
ment. Increasing the switching frequency or the inductor  
value lowers the peak-to-average current ratio, yielding a  
lower input-capacitance requirement.  
capacitor). Use low-ESR ceramic or aluminum electrolytic  
capacitors at the output. For aluminum electrolytic capaci-  
tors, the entire output ripple is contributed by ΔV  
. Use  
ESR  
Equation 4 to calculate the ESR requirement and choose  
the capacitor accordingly. If using ceramic capacitors,  
assume the contribution to the output ripple voltage from  
the ESR and the capacitor discharge to be equal. The fol-  
lowing equations show the output capacitance and ESR  
requirement for a specified output-voltage ripple.  
The input ripple comprises of ΔV (caused by the capaci-  
Q
tor discharge) and ΔV  
(caused by the ESR of the  
ESR  
input capacitor). The total voltage ripple is the sum of ΔV  
Equation 4:  
Q
and ΔV  
. Assume that input-voltage ripple from the  
ESR  
∆V  
ESR  
ESR and the capacitor discharge is equal to 50% each.  
The following equations show the ESR and capacitor  
requirement for a target voltage ripple at the input:  
ESR =  
∆I  
P−P  
∆I  
P−P  
C
=
OUT  
Equation 3:  
8× ∆V × f  
Q
SW  
∆V  
+ (∆I  
ESR  
/ 2)  
P−P  
ESR =  
I
OUT  
I
×D(1− D)  
OUT  
C
=
IN  
∆V × f  
Q
SW  
Maxim Integrated  
│ 13  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
where:  
(C  
) and the output voltage (V ) determine the mini-  
SEL OUT  
mum required soft-start capacitor as shown below.  
(V − V  
)× V  
OUT  
×L  
IN  
OUT  
∆I  
=
P−P  
V
× f  
Equation 6:  
IN SW  
V
= ∆V  
+ ∆V  
Q
C
≥ 30 x 10-6 x C  
x V  
SEL OUT  
SS  
OUT_RIPPLE  
ESR  
The soft-start time (t ) is related to the capacitor con-  
SS  
ΔI  
is the peak-to-peak inductor current as calculated  
P-P  
nected at SS (C ) by the following equation.  
SS  
above, and f  
is the converter’s switching frequency.  
SW  
Equation 7:  
Transient Response Requirement  
C
SS  
The allowable deviation of the output voltage during fast-  
transient loads also determines the output capacitance  
and its ESR. The output capacitor supplies the step-load  
current until the converter responds with a greater duty  
t
=
SS  
−6  
6.25×10  
For example, to program a 2ms soft-start time, a 12nF  
capacitor should be connected from the SS pin to SGND.  
cycle. The response time (t  
) depends on the  
RESPONSE  
closed-loop bandwidth of the converter. The high switch-  
ing frequency of the devices allows for a higher closed-  
Adjusting the Output Voltage  
Set the output voltage with resistive voltage-dividers con-  
nected from the positive terminal of the output capacitor  
loop bandwidth, thus reducing t  
and the out-  
RESPONSE  
put-capacitance requirement. The resistive drop across  
the output capacitor’s ESR and the capacitor discharge  
causes a voltage droop during a step load. Keep the  
maximum output-voltage deviations below the tolerable  
limits of the electronics being powered. When using a  
ceramic capacitor, assume an 80% and 20% contribution  
from the output-capacitance discharge and the ESR drop,  
respectively. Use the following equations to calculate the  
required ESR and capacitance value:  
(V  
) to SGND (Figure 1). Connect the center node of  
OUT  
the divider to the FB pin. To optimize efficiency and output  
accuracy, use the following calculations to choose the  
resistive divider values.  
Equation 8:  
15× V  
OUT  
R4 =  
0.8  
R4× 0.8  
− 0.8)  
R5 =  
Equation 5:  
(V  
OUT  
∆V  
where R4 and R5 are in kΩ.  
ESR  
ESR  
I
=
OUT  
I
STEP  
× t  
STEP  
RESPONSE  
C
=
OUT  
2× ∆V  
V
Q
OUT  
R4  
R5  
where I  
response time of the converter.  
is the load step and t  
is the  
STEP  
RESPONSE  
FB  
Soft-Start Capacitor Selection  
The device implements adjustable soft-start operation to  
reduce inrush current. A capacitor connected from the SS  
pin to SGND programs the soft-start time for the corre-  
sponding output voltage. The selected output capacitance  
Figure 1. Setting the Output Voltage  
Maxim Integrated  
│ 14  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
should be routed away from the inductor.  
Series R-C Selection  
To achieve higher bandwidth, connect an R-C series circuit  
across the bottom feedback resistor (see Figure 2).  
2) Solder the exposed pad to a large copper-plane area  
under the device. To effectively use this copper area  
as heat exchanger between the PCB and ambient,  
expose the copper area on the top and bottom side.  
Add a few small vias or one large via on the copper  
pad for efficient heat transfer. Connect the exposed  
pad to PGND, ideally at the return terminal of the  
output capacitor.  
Select the R-C (R6 and C6) values using Equations 9  
and 10.  
Equation 9:  
R4×R5  
R4 + R5 1− 0.99k  
k
R6 =  
×
6
1.125×10  
3) Isolate the power components and high-current  
paths from sensitive analog circuitry.  
C6 =  
k
f
×R6×  
C
2
4) Keep the high-current paths short, especially at  
the ground terminals. This practice is essential for  
stable, jitter-free operation.  
1− k  
where:  
And C  
R4  
R5  
5) Connect PGND and SGND together, preferably at  
the return terminal of the input capacitor. Do not con-  
nect them anywhere else.  
f
× C  
× 1+  
C
OUT  
k =  
3.6274  
6) Keep the power traces and load connections short.  
This practice is essential for high efficiency. Use  
thick copper PCB to enhance full-load efficiency and  
power-dissipation capability.  
is the derated capacitance value for a given  
OUT  
bias voltage in µF, f is the targeted crossover frequency  
in Hz, (15kHz or 1/20th of f ; whichever is lower) R4  
and R5 are the feedback network in kΩ, R6 is in kΩ, and  
C6 is in nF.  
C
SW  
7) Route high-speed switching nodes away from sensi-  
tive analog areas. Use internal PCB layers as PGND  
to act as EMI shields to keep radiated noise away  
from the device and analog bypass capacitor.  
Setting the Undervoltage Lockout  
Drive EN/UVLO high to enable the output. Leave the pin  
unconnected for always-on operation. Set the voltage at  
which each converter turns on with a resistive voltage-  
V
OUT  
divider connected from V to SGND (see Figure 3).  
IN  
R4  
Connect the center node of the divider to EN/UVLO pin.  
FB  
Equation 10 (choose R1 as follows):  
R6  
R1 ≤ (110000 x V  
)
INU  
R5  
where V  
is the input voltage at which the device is  
INU  
C6  
required to turn on and R1 is in Ω. Calculate the value of  
SGND  
R2 as shown in Equation 11.  
Equation 11:  
Figure 2. R-C Network for Increased Phase Margin  
1.215×R1  
R2 =  
V
−1.215 + (2.5µA ×R1)  
(
)
INU  
V
IN  
PCB Layout Guidelines  
R1  
R2  
Careful PCB layout is critical to achieve low switching  
power losses and clean, stable operation. Use a multi-  
layer board wherever possible for better noise immunity.  
Follow the guidelines below for a good PCB layout:  
EN/UVLO  
1) Place the input capacitor right next to the V pin.  
IN  
The bypass capacitor for the V  
pin should be as  
CC  
Figure 3. Undervoltage-Lockout Divider  
close as possible to the pin. The feedback trace  
Maxim Integrated  
│ 15  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Typical Application Circuit  
V
OUT  
L1  
5V, 1A  
V
IN  
LX  
V
IN  
33µH  
MAX20058  
C4  
R4  
95.3kΩ  
22µF  
C1  
2.2µF  
EN/UVLO  
MODE/ILIM  
FB  
V
CC  
PGND  
R6  
C2  
16.9kΩ  
1µF  
R5  
18.2kΩ  
C6  
4.7nF  
SGND  
RT/SYNC  
SS  
R1  
105kΩ  
RESET  
C3  
12nF  
4.7Ω  
V
OUT  
EXTVCC  
0.1µF  
CIRCUIT FOR 5V OUTPUT, f = 400kHz  
SW  
(PFM MODE, 1.6 A CURRENT LIMIT)  
Chip Information  
PROCESS: CMOS  
Ordering Information  
PART  
TEMP RANGE  
PIN-PACKAGE  
MAX20058ATCA/VY+ -40°C to +125°C 12 SW TDFN-EP*  
/V Denotes an automotive-qualified part.  
+Denotes a lead(Pb)-free/RoHS-compliant package.  
SW = Side-wettable package.  
*EP = Exposed pad.  
Maxim Integrated  
│ 16  
www.maximintegrated.com  
MAX20058  
60V, 1A, Automotive Synchronous  
Step-Down DC-DC Converter  
Revision History  
REVISION REVISION  
PAGES  
CHANGED  
DESCRIPTION  
NUMBER  
DATE  
0
3/18  
Initial release  
—
Updated Output Voltage Range and last row in Switching Frequency rows in  
Electrical Characteristics table; replaced TOC04 and updated TOC12 in Typical  
Operating Characteristics section; updated Switching-Frequency Selection and  
External Frequency Synchronization section and the last row in Table 2  
1
2
6/18  
4/19  
3, 4, 6, 7, 12  
2, 14, 15  
Updated Absolute Maximum Rating, Equation 6 and Series R-C Selection section  
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.  
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.  
2019 Maxim Integrated Products, Inc.  
│ 17  
厂商 型号 描述 页数 下载

COOPER

 		MAX [ Blade-Type Fuses ] 1 页

MDE

 		MAX-100 大电流瞬态电压抑制器[ HIGH CURRENT TRANSIENT VOLTAGE SUPPRESSOR ] 2 页

MINI

 		MAX-19H 有源混频器[ Active Mixer ] 1 页

MAXIM

 		MAX-20 保险丝\n[ Fuse ] 1 页

MDE

 		MAX-200 大电流瞬态电压抑制器[ HIGH CURRENT TRANSIENT VOLTAGE SUPPRESSOR ] 2 页

MDE

 		MAX-225 大电流瞬态电压抑制器[ HIGH CURRENT TRANSIENT VOLTAGE SUPPRESSOR ] 2 页

ETC

 		MAX-25 [ FUSE AUTO 25A 32VDC BLADE ] 1 页

SLPOWER

 		MAX-250 250 ， 350瓦多输出[ 250, 350 WATTS MULTIPLE OUTPUT ] 2 页

SLPOWER

 		MAX-254-1205 [ 250, 350 WATTS MULTIPLE OUTPUT ] 2 页

MAXIM

 		MAX-256-X 光电\n[ Optoelectronic ] 4 页

购物指南

支付方式

配送服务

售后服务

发票须知

优惠券使用规则

代理产品

代理品牌

代理器件

特色服务

PCBA制造

国产品牌推荐

国产料号替代

质量保证

技术资料

行业资讯

关于我们

关于壹壹捌

联系我们

联系我们

服务热线：400-618-9990

企业邮箱：sales@ic118.com

服务时间：周一至周六 8:30-17:30

壹壹捌官方微信号

PDF索引：

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

0

1

2

3

4

5

6

7

8

9

IC型号索引：

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

0

1

2

3

4

5

6

7

8

9

Copyright 2024 gkzhan.com Al Rights Reserved 京ICP备06008810号-21 京

深圳网络警察报警平台
公共信息安全网络监察
经营性网站备案信息
不良信息举报中心
工商网监电子标识
全国公安机关备案
0.291204s