MAX25202MATEAVY [MAXIM]

36V HV Synchronous Boost Controller for Automotive Infotainment Applications;
MAX25202MATEAVY
型号: MAX25202MATEAVY
厂家: MAXIM INTEGRATED PRODUCTS    MAXIM INTEGRATED PRODUCTS
描述:

36V HV Synchronous Boost Controller for Automotive Infotainment Applications

文件: 总22页 (文件大小:1372K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
EVALUATION KIT AVAILABLE  
Click here for production status of specific part numbers.  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
General Description  
Benefits and Features  
● Meets Stringent OEM Module Power Consumption  
The MAX2501/MAX25202 are high-performance, current-  
mode PWM controllers with 1.5μA (typ) shutdown cur-  
rent for wide input voltage range boost converters. The  
4.5V to 36V input operating voltage range makes these  
devices ideal in automotive applications, such as front-  
end preboost or general-purpose boost power supply, for  
the first boost stage in high-power LED lighting applica-  
tions or to generate audio amplifier voltages. An internal  
low-dropout regulator with a 5V output voltage enables  
the MAX25201/MAX25202 to operate directly from an  
automotive battery input. The input operating range can  
be extended to as low as 1.8V after startup.  
and Performance Specifications  
20µA Quiescent Current in Skip Mode  
±1.5% FB Voltage Accuracy  
Output Voltage Range: Fixed or Adjustable  
Between 3.5V and 60V  
● Enables Crank-Ready Designs  
Operates Down to 1.8V After Startup  
Wide Input Supply Range from 4.5V to 36V  
● EMI Reduction Features Reduce Interference with  
Sensitive Radio Bands Without Sacrificing Wide Input  
Voltage Range  
The MAX25201/MAX25202’s switching frequency opera-  
tion (up to 2.2MHz) reduces output ripple, avoids AM band  
interference, and allows for the use of smaller external  
components. The switching frequency is resistor adjust-  
able from 220kHz to 2.2MHz. Alternatively, the frequency  
can be synchronized to an external clock. A spread-  
spectrum option is available to improve system EMI per-  
formance. For high-current applications the dual-phase  
MAX25202 is available. The MAX25202 operates at a  
fixed 400kHz switching frequency and can be synchro-  
nized to an external clock.  
Spread-Spectrum Option  
Frequency-Synchronization Input  
Resistor-Programmable Frequency Between  
200kHz and 2.2MHz  
● Integration and Thermally Enhanced Packages Save  
Board Space and Cost  
• Current-Mode Controllers with Forced-Continuous  
and Skip Modes  
Thermally Enhanced 16-Pin TQFN-EP Package  
● Protection Features Improve System Reliability  
Supply Undervoltage Lockout  
The controllers feature a power-OK monitor and under-  
voltage lockout. Protection features include cycle-by-  
cycle current limit and thermal shutdown. The MAX25201/  
MAX25202 operate over the -40°C to +125°C automotive  
temperature range.  
Overtemperature and Short-Circuit Protection  
Applications  
Infotainment Systems  
Cluster Systems  
E-Call  
Ordering Information appears at end of data sheet.  
19-100588; Rev 3; 2/20  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Simplified Block Diagram  
PGOOD  
SS  
COMP  
EN  
FB  
THRES  
SOFT START  
EAMP  
REF  
BST  
SUP  
BIAS  
EN  
OUT  
DH  
LX  
BIAS LDO  
GATE  
DRIVE  
PWM  
SUP  
CS  
CSA  
PWM  
ILIM  
DL  
ZX  
LX  
ILIM THRES  
SLOPE COMP  
LOGIC  
GND  
ZERO CROSS  
FOSC  
OSCILLATOR  
SPS OTP  
MODE/  
FSYNC  
(SKIP MODE )  
(PWM MODE )  
FSYNC  
SELECT  
LOGIC  
Maxim Integrated  
2  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Absolute Maximum Ratings  
SUP, EN to GND .....................................................-0.3V to 42V  
OUT, FB, LX to GND...............................................-0.3V to 65V  
SUP to CS..............................................................-0.3V to 0.3V  
BIAS, MODE/FSYNC, PGOOD, SS to GND.............-0.3V to 6V  
DL, FOSC, COMP to GND........................ -0.3V to BIAS + 0.3V  
BST to LX..................................................................-0.3V to 6V  
DH to LX........................................................-0.3V to BST+0.3V  
Continuous Power Dissipation  
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  
TQFN (derate 28.8mW/°C* above +70°C) ................1666mW  
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.  
Recommended Operating Conditions  
PARAMETER  
SYMBOL  
CONDITION  
TYPICAL RANGE  
UNIT  
Ambient Temperature  
Range  
-40 to 125  
°C  
Note: These limits are not guaranteed.  
Package Information  
TQFN  
Package Code  
T1633Y+5C  
Outline Number  
21-100150  
90-100064  
Land Pattern Number  
Thermal Resistance, Four-Layer Board:  
Junction to Ambient (θ  
)
44.5°C/W  
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  
3  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Electrical Characteristics  
(V  
= 14V, V  
= 14V, C  
= 1μF, C  
= 0.1μF, T = -40°C to +150°C, unless otherwise noted. Typical values are at T =  
BST J A  
SUP  
EN  
BIAS  
+25°C.) (Note 2)  
PARAMETER  
SYMBOL  
CONDITIONS  
MIN  
TYP  
MAX  
UNITS  
STEP UP CONTROLLER  
Initial startup, V  
= V  
4.5  
1.8  
36  
36  
OUT  
BATT  
Supply Voltage Range  
V
V
Operation after initial startup condition is satisfied  
SUP  
Output Over-Voltage  
Threshold  
Detected with respect to V rising  
102.0  
105  
25  
107.5  
%
FB  
V
V
= V  
, V = V  
(fixed output voltage),  
EN  
SUP FB  
BIAS  
> V  
, no load (MAX25201)  
SUP  
OUT  
V
EN  
= V  
, V  
> V  
, adjustable output, no  
SUP SUP  
OUT  
load. Excludes current through external FB divider  
(MAX25201)  
20  
Supply Current  
I
IN  
µA  
Shutdown, V  
= 0V, xed output voltage  
1.5  
1.5  
3
3
EN  
EN  
Shutdown, V  
current through external FB divider  
= 0V, adjustable output, excludes  
V
= V , PWM mode, MAX25201ATEA/VY+  
FB  
BIAS  
9.85  
10.04  
10.04  
10.25  
and MAX25201ATEB/VY+ only  
Fixed Output Voltage  
V
V
V
OUT  
V
= V , skip mode, MAX25201ATEA/VY+  
FB  
BIAS  
9.70  
10.30  
36  
and MAX25201ATEB/VY+ only  
MAX25201ATEA/VY+ and MAX25201ATEB/VY+  
3.5  
Output Voltage  
Adjustable Range  
MAX25201ATEC/VY+, MAX25201ATED/  
VY+, MAX25202MATEA/VY+,  
MAX25202SATEA/VY+  
20  
60  
Regulated Feedback  
Voltage  
V
0.99  
1.005  
0.01  
0.01  
250  
1.02  
1
V
FB  
Feedback Leakage  
Current  
I
T
= 25°C  
µA  
FB  
A
Feedback Line  
Regulation Error  
V
= 3.5V to 36V, V = 1V  
%/V  
µS  
IN  
FB  
Transconductance  
(from FB to COMP)  
gm_boost  
V
= 1V, V  
= 5V (Note 1)  
165  
345  
FB  
BIAS  
DL low to DH rising  
DH low to DL rising  
20  
20  
Dead Time  
ns  
DH Pullup Resistance  
V
V
V
V
= 5V, I  
= -100mA  
1.5  
2.6  
2
Ω
Ω
BIAS  
BIAS  
BIAS  
BIAS  
DH  
DH  
DH Pulldown  
Resistance  
= 5V, I  
= 100mA  
1
1.5  
1
DL Pullup Resistance  
= 5V, I = -100mA  
2.8  
2
Ω
DL  
DL Pulldown  
Resistance  
= 5V, I = 100mA  
Ω
DL  
Minimum Off Time  
t
80  
ns  
MHz  
OFFBST  
PWM Switching  
Frequency Range  
f
MAX25201, programmable with R  
0.22  
2.2  
SW  
FOSC  
R
= 70kΩ, V  
= 5V, 3.3V (MAX25201)  
380  
400  
400  
420  
425  
Switching Frequency  
Accuracy  
FOSC  
BIAS  
kHz  
MAX25202M/MAX25202S  
375  
Maxim Integrated  
4  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Electrical Characteristics (continued)  
(V  
= 14V, V  
= 14V, C  
= 1μF, C  
= 0.1μF, T = -40°C to +150°C, unless otherwise noted. Typical values are at T =  
SUP  
EN  
BIAS  
BST J A  
+25°C.) (Note 2)  
PARAMETER  
SYMBOL  
CONDITIONS  
MIN  
40  
TYP  
50  
MAX  
60  
UNITS  
MAX25201  
MAX25202M/S  
CS Current-Limit  
Voltage Threshold  
V
5V, V  
- V ; V  
=
SUP  
CS BIAS  
V
mV  
LIMIT  
> 2.5V  
36  
48  
60  
SUP  
Soft-Start Current  
Source  
I
V
= 5V  
BIAS  
8
10  
12  
µA  
µA  
SS  
LX Leakage Current  
V
= V  
or V  
, T = 25°C  
0.001  
94.5  
92.5  
5
LX  
PGND  
SUP  
A
PGOOD_H % of V , rising  
92.5  
90.5  
96.5  
94.5  
FB  
PGOOD Threshold  
%
PGOOD_F % of V , falling  
FB  
PGOOD Leakage  
Current  
V
= 5V, T = 25°C  
A
1
µA  
V
PGOOD  
PGOOD Output Low  
Voltage  
I
= 1mA  
0.2  
PGOOD  
PGOOD Debounce  
Time  
Fault detection, rising and falling  
150  
1.5  
µs  
PGOOD Timeout  
Output in regulation to PGOOD high  
ms  
FSYNC INPUT  
Minimum sync pulse of 100ns, f  
OSC  
= 2.2MHz  
= 400kHz  
1.8  
250  
1.4  
2.6  
MHz  
kHz  
FSYNC Frequency  
Range  
Minimum sync pulse of 100ns, f  
High threshold  
550  
OSC  
FSYNC Switching  
Thresholds  
V
Low threshold  
0.4  
INTERNAL LDO BIAS  
Internal BIAS Voltage  
V
V
V
> 6V  
5
V
V
IN  
rising  
falling  
3.1  
2.6  
3.25  
BIAS  
BIAS  
BIAS UVLO Threshold  
2.4  
Minimum Current  
Capability  
V
= 5V  
150  
mA  
BIAS  
THERMAL OVERLOAD  
Thermal Shutdown  
Temperature  
(Note 1)  
(Note 1)  
170  
°C  
°C  
Thermal Shutdown  
Hysteresis  
20  
EN LOGIC INPUT  
High Threshold  
1.8  
V
V
Low Threshold  
0.8  
1
EN Input Bias Current  
SPREAD SPECTRUM  
EN logic inputs only, T = 25°C  
0.01  
µA  
A
f
±
OSC  
6%  
Spread Spectrum  
Note 1: Limits are 100% tested at +25°C. Limits over operating temperature range and relevant supply voltage are guaranteed by  
design and characterization. Typical values are at +25°C.  
Note 2: The device is designed for continuous operation up to T = +125°C for 95,000 hours and T = +150°C for 5,000 hours.  
J
J
Maxim Integrated  
5  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Typical Operating Characteristics  
(V  
= 14V, T = 25°C, unless otherwise noted.)  
SUP  
A
OUTPUT VOLTAGE  
vs. INPUT VOLTAGE  
OUTPUT VOLTAGE  
vs. INPUT VOLTAGE  
MAX25201 EFFICIENCY  
vs. LOAD CURRENT  
toc02  
toc03  
toc01  
8.16  
8.12  
8.08  
8.04  
8
100  
95  
90  
85  
80  
75  
70  
65  
60  
55  
50  
24.5  
7V INPUT  
2.1MHz FPWM  
8V OUTPUT  
24.4  
24.3  
24.2  
24.1  
24  
0A LOAD  
5V INPUT  
0A LOAD  
4A LOAD  
3V INPUT  
CURRENT  
LIMIT  
2A LOAD  
4A LOAD  
23.9  
23.8  
23.7  
23.6  
23.5  
7.96  
7.92  
7.88  
7.84  
8V OUT  
400kHz FPWM  
24V OUTPUT  
2.1MHz FPWM  
RCS = 3mΩ  
1
3
0
0
4
5
6
7
8
0
0
6
2
3
4
5
6
4
8
12  
16  
20  
24  
INPUT VOLTAGE (V)  
LOAD CURRENT (A)  
INPUT VOLTAGE (V)  
MAX25201 EFFICIENCY  
vs. LOAD CURRENT  
MAX25201 EFFICIENCY  
vs. LOAD CURRENT  
MAX25201 EFFICIENCY  
vs. LOAD CURRENT  
toc05  
toc06  
toc04  
100  
95  
90  
85  
80  
75  
100  
95  
90  
85  
80  
75  
100  
95  
90  
85  
80  
75  
70  
65  
60  
55  
50  
7V INPUT  
21V INPUT  
14V INPUT  
14V INPUT  
5V INPUT  
21V INPUT  
3V INPUT  
4.5V INPUT  
4.5V INPUT  
CURRENT  
LIMIT  
CURRENT  
LIMIT  
8V OUT  
2.1MHz  
SKIP  
24V OUT  
400kHz  
SKIP  
24V OUT  
RCS = 1.5mΩ  
RCS = 1.5mΩ  
400kHz FPWM  
RCS = 3mΩ  
1
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
0
2
3
4
5
6
LOAD CURRENT (A)  
LOAD CURRENT (A)  
LOAD CURRENT (A)  
OUTPUT VOLTAGE  
vs. LOAD CURRENT  
QUIESCENT CURRENT  
vs. SUPPLY VOLTAGE  
OUTPUT VOLTAGE  
vs. LOAD CURRENT  
toc07  
toc09  
toc08  
8.15  
8.1  
50  
40  
30  
20  
10  
0
24.5  
24.4  
24.3  
24.2  
24.1  
24  
21V INPUT  
7V INPUT  
14V INPUT  
5V INPUT  
8.05  
8
4.5V INPUT  
23.9  
23.8  
23.7  
23.6  
23.5  
3V INPUT  
7.95  
7.9  
8V OUT  
24V OUT  
400kHz FPWM  
2.1MHz FPWM  
VFB = 1.15V  
30  
7.85  
0
0.5  
1
1.5  
2
2.5  
3
3.5  
4
12  
18  
24  
36  
0.5  
1
1.5  
2
2.5  
3
3.5  
4
LOAD CURRENT (A)  
SUPPLY VOLTAGE (V)  
LOAD CURRENT (A)  
Maxim Integrated  
6  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Typical Operating Characteristics (continued)  
(V  
= 14V, T = 25°C, unless otherwise noted.)  
SUP  
A
COLD-CRANK INPUT  
VOLTAGE TRANSIENT  
SHUTDOWN SUPPLY CURRENT  
vs. SUPPLY VOLTAGE  
toc11  
toc10  
4
VSUP  
8V/div  
3.5  
3
0V  
10V/div  
2.5  
2
VOUT  
0V  
1.5  
1
5V/div  
0V  
VPGOOD  
0.5  
0
5V/div  
VBIAS  
0V  
0
4
8
12 16 20 24 28 32 36  
SUPPLY VOLTAGE (V)  
50ms/div  
INPUT UNDERVOLTAGE PULSE  
SUPPLY VOLTAGE RAMP  
toc12  
toc13  
10V/div  
10V/div  
VSUP  
VSUP  
0V  
0V  
10V/div  
10V/div  
VOUT  
VOUT  
0V  
0V  
5V/div  
0V  
5V/div  
0V  
VPGOOD  
VPGOOD  
5V/div  
5V/div  
0V  
VBIAS  
VBIAS  
0V  
5s/div  
500ms/div  
POWER-UP RESPONSE  
POWER-UP RESPONSE  
toc15  
toc14  
10V/div  
10V/div  
VSUP  
VSUP  
0V  
0V  
12V/div  
12V/div  
VOUT  
VOUT  
0V  
0V  
5V/div  
0V  
5V/div  
0V  
VPGOOD  
VPGOOD  
5V/div  
5V/div  
VBIAS  
VDL  
0V  
0V  
3ms/div  
3ms/div  
Maxim Integrated  
7  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Typical Operating Characteristics (continued)  
(V  
= 14V, T = 25°C, unless otherwise noted.)  
SUP  
A
STARTUP RESPONSE  
STARTUP RESPONSE  
toc16  
toc17  
10V/div  
10V/div  
VSUP  
VSUP  
0V  
0V  
12V/div  
12V/div  
VOUT  
VOUT  
0V  
0V  
5V/div  
0V  
5V/div  
0V  
VPGOOD  
VBIAS  
5V/div  
5V/div  
VEN  
VEN  
0V  
0V  
3ms/div  
3ms/div  
SWITCHING WAVEFORM  
LOAD TRANSIENT RESPONSE  
toc19  
toc18  
10V/div  
10V/div  
VSUP  
VOUT  
VSUP  
0V  
500mV/div  
(AC)  
0V  
20V/div  
VOUT  
0V  
12V/div  
VOUT  
14V/div  
0V  
VLX  
0V  
2A/div  
ILOAD  
4A/div  
ILOAD  
0A  
0A  
5µs/div  
1ms/div  
Maxim Integrated  
8  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Pin Configurations  
MAX25201  
MAX25202M  
DUAL PHASE MASTER  
TOP VIEW  
TOP VIEW  
16  
15  
14  
13  
16  
15  
14  
13  
CS  
SUP  
OUT  
FB  
+
1
2
3
4
12  
11  
10  
9
DL  
+
CS  
SUP  
OUT  
FB  
1
2
3
4
12  
11  
10  
9
DL  
GND  
BIAS  
FOSC  
GND  
MAX25201  
MAX25202M  
BIAS  
FSYNCOUT  
5
6
7
8
5
6
7
8
SW TQFN  
3mm x 3mm  
SW TQFN  
3mm x 3mm  
MAX25202S  
DUAL PHASE SLAVE  
TOP VIEW  
16  
15  
14  
13  
+
CS  
1
2
3
4
12  
11  
10  
9
DL  
SUP  
OUT  
FB  
GND  
BIAS  
NC  
MAX25202S  
5
6
7
8
SW TQFN  
3mm x 3mm  
Maxim Integrated  
9  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Pin Description  
PIN  
NAME  
FUNCTION  
MAX25201 MAX25202M MAX25202S  
Negative Current-Sense Input for Boost Controller. Connect CS to the  
negative side of the current-sense element. See the Current Limiting  
and Current-Sense Inputs (SUP and CS) and Current-Sense Resistor  
Selection sections.  
1
1
1
CS  
Supply Input and Positive Current-Sense Input for Boost Controller. Con-  
nect SUP to the positive terminal of the current-sense element. See the  
Current Limiting and Current-Sense Inputs (SUP and CS) and Current  
Sense Measurement sections.  
2
3
2
3
2
3
SUP  
OUT  
Input for the BIAS LDO. Connect OUT to the boost output when the  
output voltage is set at 24V or below. For V  
greater than 24V,  
OUT  
connect OUT to the input supply.  
Boost Converter Feedback Input. To set the output voltage between  
3.5V and 60V, connect FB to the center tap of a resistive divider be-  
tween the boost regulator output. FB regulates to 1V (typ). To use the  
factory set fixed output voltage on applicable parts (see the Ordering  
Information section, connect FB to BIAS and connect OUT to the output.  
For more information, see the Setting the Output Voltage section.  
4
5
4
5
4
5
FB  
Boost Controller Error Amplifier Output. Connect a RC network to COMP  
to compensate boost converter.  
COMP  
Programmable Soft-Start. Connect a capacitor from SS to GND to set  
the soft-start time. To select the value, see the Typical Operating Char-  
acteristics section.  
6
6
6
SS  
MODE  
Connect to FSYNCIN of the MAX25202M.  
Open-Drain Power-Good Output for Buck Controller One. PGOOD goes  
low if OUT drops below 92.5% (typ falling) of the normal regulation  
point. PGOOD asserts low during soft-start and in shutdown. PGOOD  
becomes high impedance when OUT is in regulation. To obtain a logic  
signal, pull up PGOOD with an external resistor connected to a positive  
voltage lower than 5.5V.  
7
7
PGOOD  
NC  
8
7, 9  
Do Not Connect  
External Clock Synchronization Input. To use the internal oscillator con-  
nect MODE/FSYNC high for forced-PWM or low for skip-mode opera-  
tion. To synchronize with an external clock, connect the clock to MODE/  
FSYNC. See the Light-Load Efficiency Skip Mode and Forced-PWM  
Mode sections.  
MODE/  
FSYNC  
Synchronization Input. Connect to an external clock for synchronization.  
Connect to ground for internal frequency setting. When an external  
signal is connected, the spread spectrum is disabled.  
8
FSYNCIN  
Slave Input Synchronization. For dual-phase operation, connect FSYN-  
CINS of the MAX25202S to FSYNCOUT of the MAX25202M.  
9
8
FSYNCINS  
FOSC  
Frequency Setting Input. Connect a resistor to FOSC to set the  
switching frequency of the DC-DC converters.  
Maxim Integrated  
10  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Pin Description (continued)  
PIN  
NAME  
FUNCTION  
MAX25201 MAX25202M MAX25202S  
Clock Synchronization Output. Connect FSYNCOUT to FSYNCINS of  
the MAX25202S.  
9
FSYNCOUT  
5V Internal Linear Regulator Output. Bypass BIAS to GND with a low-  
ESR ceramic capacitor of 1µF minimum value. BIAS provides the power  
to the internal circuitry and external loads. See the Fixed 5V Linear  
Regulator (BIAS) section.  
10  
10  
10  
BIAS  
11  
12  
11  
12  
11  
12  
GND  
Ground  
DL  
Low-Side N-Channel MOSFET Gate Driver Output  
Inductor Connection for Boost Controller. Connect LX to the switched  
side of the inductor. LX serves as the lower supply rail for the DH high-  
side gate driver.  
13  
14  
13  
14  
13  
14  
LX  
High-Side MOSFET Gate Driver Output for Boost Controller. DH output  
DH  
voltage swings from V to V  
.
LX  
BST  
Boost Flying Capacitor Connection for High-Side Gate Voltage of Boost  
Controller. Connect a high-voltage diode between BIAS and BST. Connect  
a ceramic capacitor between BST and LX. See the High-Side Gate-  
Driver Supply (BST) section.  
15  
16  
15  
16  
15  
16  
BST  
EN  
High-Voltage Tolerant, Active-High Digital Enable Input for Controller  
Exposed Pad. Connect the exposed pad to ground. Connecting the  
exposed pad to ground does not remove the requirement for proper  
ground connections to GND. The exposed pad is attached with epoxy to  
the substrate of the die, making it an excellent path to remove heat from  
the IC.  
EP  
Maxim Integrated  
11  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
The OUT pin is the input to the linear regulator. OUT is  
typically connected to the boost output for applications  
with the output voltage set to 24V or less and applica-  
tions that require operation with a supply voltage below  
5.2V. To reduce power dissipation in applications with  
higher output voltages, OUT should be connected to  
SUP. Bypass OUT with a 1µF or greater ceramic capaci-  
tor to GND.  
Detailed Description  
The MAX25201/MAX25202 automotive controller main-  
tains regulation during cold crank or start-stop operations  
down to a battery input of 1.8V, and operates with only  
20μA I . The devices generate backlight voltages, audio  
Q
amplifier voltages, stand-alone preboost, as well as a  
standby voltage in telematics applications. The devices  
can start up with an input voltage supply from 3.5V to 42V  
and can operate down to 1.8V after startup.  
Startup Operation/UVLO/EN  
The MAX25201/MAX25202’s 2.2MHz switching frequency  
reduces output ripple, avoids AM band interference, and  
allows for the use of smaller external components. The  
switching frequency is resistor adjustable from 220kHz to  
2.2MHz. Alternatively, the frequency can be synchronized  
to an external clock. A spread-spectrum option is avail-  
able to improve system EMI performance.  
The BIAS undervoltage lockout (UVLO) circuitry inhibits  
switching if the 5V bias supply (BIAS) is below its 2.6V  
(typ) UVLO falling threshold. Once BIAS rises above its  
UVLO rising threshold and EN is high, the boost controller  
starts switching and the output voltage begins to ramp up  
using soft-start. Driving EN low disables the device and  
reduces the standby current to less than 10μA.  
These controllers feature a power-OK monitor as well as  
overvoltage and undervoltage lockout. Protection features  
include cycle-by-cycle current limit and thermal shutdown.  
The MAX25201/MAX25202 are specified for operation  
over the -40°C to +125°C automotive temperature range.  
Soft-Start  
Soft-start ramps up the internal reference during startup  
to reduce input surge current. Connect a capacitor from  
SS to GND to set the soft-start time. Select the capacitor  
value as follows:  
Current-Mode Control Loop  
C
[nF] = 10 × t [ms]  
ss  
SS  
Peak current-mode control operation provides excellent  
load step performance and simple compensation. The  
inherent feed-forward characteristic is useful especially in  
automotive applications where the input voltage changes  
quickly during cold-crank and load dump conditions.  
To avoid premature turn-off at the beginning of the on  
cycle the current-limit and PWM comparator inputs have  
leading-edge blanking.  
Soft-start begins when EN is logic-high and V  
above the undervoltage lockout threshold.  
is  
BIAS  
Oscillator Frequency/External  
Synchronization  
The MAX25201's internal oscillator is set by a resistor  
connected from FOSC to GND with an adjustment range  
of 220kHz to 2.2MHz. High-frequency operation optimizes  
the application for the smallest component size, trading  
off efficiency to higher switching losses. Low-frequency  
operation offers the best overall efficiency at the expense  
of component size and board space.  
Fixed 5V Linear Regulator (BIAS)  
An internal 5V linear regulator (BIAS) is used to power  
the controller's internal circuitry. Connect a 1μF or greater  
ceramic capacitor from BIAS to GND as close as possible  
to the IC pins to guarantee stability under the full-load  
condition. The internal linear regulator can provide up to  
150mA (typ) total. The internal bias current requirements  
can be estimated as follows:  
R
FOSC  
24500 +  
0.006  
F
=
SW  
R
FOSC  
I
= I  
+ f  
(QG_DL + QG_DH)  
BIAS  
CC  
SW  
where:  
The MAX25202's internal oscillator is fixed at 400kHz.  
I
= the internal supply current  
= the switching frequency  
The devices can also be synchronized to an external  
clock by connecting the external clock signal to MODE/  
FSYNC (MAX25201) or FSYNCIN (MAX25202M). The  
internal oscillator is synchronized on the rising edge of the  
external clock. See the Electrical Characteristics table for  
the FSYNC frequency range and voltage levels.  
CC  
f
SW  
QG_ = the low- and high-side MOSFET total gate charge  
(specification limits at V = 5V).  
GS  
To reduce the internal power dissipation, BIAS can option-  
ally be connected to an external 5V rail, bypassing the  
internal linear regulator.  
Maxim Integrated  
12  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
voltage of the external MOSFETs. A low-resistance, low-  
inductance path from DL and DH to the MOSFET gates  
is required in order for the protection circuits to work  
properly.  
Light-Load Efficiency Skip Mode  
The skip mode feature of the MAX25201/MAX25202 is  
used to improve light-load efficiency. Drive MODE/FSYNC  
low to enable skip mode.  
In skip mode, once the output reaches regulation, the  
MAX25201/MAX25202 stop switching until the FB voltage  
drops below the reference voltage. Once the FB voltage  
has dropped below the reference voltage, the devices  
resume switching until the inductor current reaches 30%  
(skip threshold) of the maximum current set by the induc-  
tor DCR or current-sense resistor.  
High-Side Gate-Driver Supply (BST)  
The high-side MOSFET is turned on by closing an inter-  
nal switch between BST and DH and transferring the  
bootstrap capacitor’s (at BST) charge to the gate of the  
high-side MOSFET. This charge refreshes when the high-  
side MOSFET turns off and the LX voltage drops down  
to ground potential, taking the negative terminal of the  
capacitor to the same potential. The bootstrap diode then  
recharges the positive terminal of the bootstrap capacitor.  
Forced-PWM Mode  
Drive MODE/FSYNC of the MAX25201/MAX25202 high  
(connect to BIAS) for forced-PWM operation. This pre-  
vents the devices from entering skip mode by disabling  
the zero-crossing detection of the inductor current, and  
forces the low-side gate-drive waveform to the comple-  
ment of the high-side gate-drive waveform. Under light-  
load the inductor current reverses, discharging the output  
capacitor. The benefit of forced-PWM mode is that it  
keeps the switching frequency constant under all load  
conditions. This reduces ripple and makes it predict-  
able and easier to filter. Forced-PWM mode is useful  
for improving load-transient response and eliminating  
unknown frequency harmonics that can interfere with AM  
radio bands. The disadvantage with forced-PWM opera-  
tion is that it reduces light-load efficiency.  
The selected n-channel high-side MOSFET determines  
the appropriate boost capacitance values according to the  
following equation:  
C
BST  
= Q /∆V  
G BST  
where:  
= the total gate charge of the high-side MOSFET  
Q
G
∆V  
= the voltage variation allowed on the high-  
BST  
side MOSFET driver after turn-on. Choose ∆V  
such  
BST  
that the available gate-drive voltage is not significantly  
degraded (e.g., V = 100mV to 300mV) when deter-  
BST  
mining C  
. The boost capacitor should be a low-ESR  
BST  
ceramic capacitor. A minimum value of 0.1μF works well  
in most cases.  
Forced-PWM is always used when synchronizing to an  
Current Limiting and Current-Sense Inputs  
(SUP and CS)  
The current-limit circuit uses differential current-sense  
inputs (SUP and CS) to limit the peak inductor current.  
If the magnitude of the current-sense signal exceeds the  
external clock and in multiphase applications.  
Spread Spectrum  
Spread spectrum reduces peak emission noise at the  
clock frequency and its harmonics, making it easier to  
meet stringent EMI limits. This is done by dithering the  
switching frequency ±6%. Using an external clock source  
(i.e. driving the MODE/FSYNC input with an external  
clock) disables spread spectrum.  
current-limit threshold (V  
> 50mV (typ)), the PWM  
LIMIT  
controller turns off the high-side MOSFET.  
For the most accurate current sensing, use a current-  
sense resistor between the inductor and the input capaci-  
Spread spectrum is a factory set option. See the Ordering  
Information section to determine which part numbers  
have spread spectrum enabled.  
tor. Connect CS to the inductor side of R  
and SUP  
CS  
to the capacitor side. See the Current-Sense Resistor  
Selection section to determine the resistor value.  
MOSFET Drivers (DH and DL)  
To improve efficiency, the current can also be measured  
directly across the inductor, eliminating the power loss  
from the sense resistor. However, this method is sig-  
nificantly less accurate and requires a filter network in  
the current-sense circuit. See the Inductor DCR Current  
Sense section for more information.  
The DH high-side n-channel MOSFET driver is pow-  
ered from BST. The low-side driver (DL) is powered  
from BIAS. To prevent a MOSFET from turning on before  
a complementary switch is fully off, each driver has  
shoot-through protection that monitors the gate-to-source  
Maxim Integrated  
13  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Voltage Monitoring (PGOOD)  
V
OUT  
PGOOD is the open-drain output of the output voltage  
monitor. PGOOD is high impedance when the output  
voltage is in regulation. PGOOD pulls low when the out-  
put voltage drops below the PGOOD threshold. See the  
Electrical Characteristics table. Typically, a pullup resistor  
is connected from PGOOD to the relevant logic rail to  
provide a logic-level output. PGOOD asserts low during  
soft-start and when disabled (EN is low).  
R1  
=
R2  
− 1  
V
[
]
FB  
where R1 is the resistor connected from FB to the output,  
R2 is the resistor connected from FB to ground, V  
the desired output voltage, and V is the regulated feed-  
is  
OUT  
FB  
back voltage (1.005V typ).  
Parts with a fixed output voltage option (see the Ordering  
Information section) can also be used without the external  
FB divider. To use the preset output voltage, connect FB  
to BIAS, and connect OUT to the regulator output.  
Protection Features  
Overcurrent Protection  
Inductor Selection  
If the inductor current exceeds the maximum current  
limit set by R  
or inductor DCR sensing, the respective  
CS  
Duty cycle and frequency are important when calculat-  
ing the inductor size because the inductor current ramps  
up during the on-time of the switch and ramps down  
during its off-time. A higher switching frequency gener-  
ally improves transient response and reduces component  
size; however, if the boost components are used as the  
input filter components during non-boost operation, a low  
frequency is advantageous.  
MOSFET driver turns off. Increasing the output current  
further results in shorter and shorter high-side pulses. A  
hard short results in a minimum on-time pulse every clock  
cycle. When required, choose components that can with-  
stand the short-circuit current.  
Thermal Overload Protection  
Thermal-overload protection limits total power dissipa-  
tion in the MAX25201/MAX25202. When the junction  
temperature exceeds +170°C (typ), an internal thermal  
sensor shuts the devices off, allowing them to cool down.  
The thermal sensor turns the devices on again after the  
junction temperature cools by 20°C (typ).  
The duty-cycle range of the boost converter depends on  
the effective input-to-output voltage ratio. In the following  
calculations, the duty cycle refers to the on-time of the  
boost MOSFET:  
V
− V  
OUT(MAX)  
V
SUP(MIN)  
D
=
MAX  
Overvoltage Protection  
OUT(MAX)  
The devices limit the output voltage by turning off the  
high-side gate driver if the output voltage exceeds 105%  
(typ) of the nominal output voltage. The output volt-  
age must come back into regulation before the devices  
resume switching.  
or including losses in the inductor and high-side MOSFET  
(VON,FET):  
V
− V  
+ I  
(
× (R  
OUT DC  
+ R  
HSRDSON  
)
)
OUT(MAX)  
SUP(MIN)  
V
D
=
MAX  
OUT(MAX)  
Slope Compensation  
The devices use an internal current-ramp generator for  
slope compensation. The slope compensation for the  
MAX25201A and MAX25201B is optimized for operation  
with output voltage set to 36V or lower. The MAX25201C,  
MAX25201D, and MAX25202 are optimized for output  
voltages between 20V and 60V.  
The ratio of the inductor peak-to-peak AC current to DC  
average current (LIR) must be selected first. A good initial  
value 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 determine the  
inductor value as follows:  
V
× D  
SUP  
MHz × LIR  
Applications Information  
L μH =  
[
]
f
[
]
SW  
Setting the Output Voltage  
where:  
All versions of the MAX25201/MAX25202 support an  
adjustable output voltage. See the Ordering Information  
section for the adjustable output voltage range. To set the  
output voltage, connect FB to the center a resistor divider  
from the output to ground. Calculate the resistor values as  
follows:  
D = (V  
-V  
)/V  
OUT SUP OUT  
V
V
= Typical input voltage  
SUP  
OUT  
= Typical output voltage  
/(1-D)  
LIR = 0.3 x I  
OUT  
Maxim Integrated  
14  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Select the inductor with a saturation current rating higher  
than the peak switch current limit of the converter:  
enough to minimize the voltage drop while supporting the  
load current. Use the following equations to calculate the  
output capacitor for a specified output ripple. All ripple  
values are peak-to-peak:  
∆ I  
L_RIP_MAX  
I
> I  
+
L_PEAK  
L_MAX  
2
Running a boost converter in continuous-conduction  
mode introduces a right-half plane zero into the transfer  
function. To avoid the effect of this right-half plane zero,  
the crossover frequency for the control loop should be ≤  
∆ V  
ESR  
ESR =  
I
OUT  
I
× D  
MAX  
1/3 x f  
. If faster bandwith is required, a smaller  
OUT  
RHP_ZERO  
C =  
∆ V × f  
inductor and higher switching frequency is recommended.  
Q
SW  
Input Capacitor Selection  
I
is the load current in A, f  
is in MHz, C  
is in  
OUT  
OUT  
SW  
The input current for the boost converter is continuous  
and the RMS ripple current at the input capacitor is low.  
Calculate the minimum input capacitor value and the  
maximum ESR using the following equations:  
μF, V is the portion of the ripple due to the capacitor  
discharge, and ∆V  
of the capacitor. D  
minimum input voltage. Use a combination of low-ESR  
ceramic and high-value, low-cost aluminum capacitors for  
lower output ripple and noise.  
Q
is the contribution due to the ESR  
is the maximum duty cycle at the  
ESR  
MAX  
∆ I × D  
L
C
=
4 × f  
SUP  
× ∆ V  
SW  
Q
Current-Sense Resistor Selection  
∆ V  
ESR  
The current-sense resistor (R ), connected between the  
CS  
ESR =  
∆ I  
L
battery and the inductor, sets the current limit. The CS  
input has a voltage trip level (V ) of 50mV (typ).  
CS  
where:  
Set the current-limit threshold high enough to accommo-  
date the component variations. Use the following equa-  
V
(
− V  
× D  
)
SUP  
L × f  
DS  
∆ I =  
tion to calculate the value of R  
:
L
CS  
SW  
V
CS  
V
is the total voltage drop across the external MOSFET  
DS  
R
=
I
CS  
SUP(MAX)  
plus the voltage drop across the inductor ESR. ∆I is the  
L
peak-to-peak inductor ripple current as calculated above.  
where I  
is the peak current that flows through the  
IN(MAX)  
∆V is the portion of input ripple due to the capacitor  
Q
MOSFET at full load and minimum V .  
IN  
discharge and ∆V  
is the contribution due to ESR of  
ESR  
the capacitor. Assume the input capacitor ripple contribu-  
I
LOAD(MAX)  
tion due to ESR (∆V ) and capacitor discharge (∆V )  
ESR  
Q
I
=
SUP(MAX)  
1 − D  
MAX  
are equal when using a combination of ceramic and alu-  
minum capacitors. During the converter turn-on, a large  
current is drawn from the input source, especially at high  
output-to-input differential.  
When the voltage produced by this current (through the  
current-sense resistor) exceeds the current-limit com-  
parator threshold, the MOSFET driver (DL) quickly termi-  
nates the on-cycle.  
Output Capacitor Selection  
In a boost converter, the output capacitor supplies the  
load current when the boost MOSFET is on. The required  
output capacitance is high, especially at higher duty  
cycles. Also, the output capacitor ESR needs to be low  
Maxim Integrated  
15  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
L
R
CS  
BATTERY  
CS  
SUP  
CURRENT SENSE RESISTOR  
L
R
DC  
BATTERY  
R2  
R1  
C
EQ  
CS  
SUP  
INDUCTOR DCR CURRENT SENSE  
Figure 1. Current-Sense Configurations  
Inductor DCR Current Sense  
Boost Converter Compensation  
High-power applications that do not require accurate cur-  
rent sense can use the inductor's DC resistance as the  
current sense element instead of the current-sense resis-  
tor. This is done by connecting an RC network across the  
inductor. The equivalent sense resistance of the network  
is:  
The basic regulator loop is modeled as a power modula-  
tor, output feedback-divider, and an error amplifier, as  
shown in the Synchronous Boost Application Circuit. The  
power modulator has a DC gain set by gmc x R  
, with  
LOAD  
a pole and zero pair set by R  
, the output capacitor  
LOAD  
(C ), and its ESR. The loop response is set by the fol-  
OUT  
lowing equations:  
R2  
R1 + R2  
R
=
× R  
f
CS_EQ  
DC  
(
)
1 + j  
f
1 − D  
2
zMOD  
f
G
= g  
× R ×  
LOAD  
×
MOD  
MC  
(
)
1 + j  
(
)
where R  
is the DC resistance of the inductor, R1 is  
connected from the switch side of the inductor to CS, and  
R2 is connected from the battery side of the inductor to  
CS. The capacitor C  
culated as follows:  
f
DC  
pMOD  
f
× 1 − j  
(
(connected parallel to R2) is cal-  
f
EQ  
)
Rph_zMOD  
where R  
= V  
/I  
in Ω and g  
is the voltage gain of the  
current-sense amplifier and is typically 12V/V. R  
DC resistance of the inductor or the current-sense resis-  
=1/  
mc  
LOAD  
OUT LOUT(MAX)  
L
1
1
(A  
V_CS  
x R ) in S. A  
DC  
V_CS  
C
=
+
R1 R2  
EQ  
(
)
R
DC  
is the  
DC  
tor in Ω.  
Maxim Integrated  
16  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
In a current-mode step-down converter, the output capaci-  
tor and the load resistance introduce a pole at the follow-  
ing frequency:  
The loop gain crossover frequency (f ) should be ≤ 1/3 of  
right-half plane zero frequency.  
C
f
Rph_zMOD  
f
C
3
1
f
=
pMOD  
π × R  
× C  
OUT  
At the crossover frequency, the total loop gain must be  
equal to 1. So:  
LOAD  
The output capacitor and its ESR also introduce a zero at:  
V
FB  
GAIN  
×
× GAIN  
= 1  
)
MOD(f  
)
EA(f  
V
C
C
1
OUT  
f
=
zMOD  
2π × ESR × C  
OUT  
GAIN  
= g  
× R  
EA(f  
)
m, EA  
C
C
The right-half plane zero is at:  
f
pMOD  
R
LOAD  
GAIN  
= GAIN  
×
MOD(dc)  
MOD(f  
)
f
=
× 1 − D × 1 − D  
)
f
(
)
(
C
Rph_zMOD  
C
2π × L  
Therefore:  
GAIN  
When C  
parallel, the resulting C  
= ESR(EACH)/n. Note that the capacitor zero for a paral-  
lel combination of similar capacitors is the same as for an  
individual capacitor.  
is composed of “n” identical capacitors in  
OUT  
= n x C  
, and ESR  
OUT  
OUT(EACH)  
V
FB  
×
× g  
× R = 1  
MOD(f  
)
m, EA C  
V
C
OUT  
Solving for R :  
C
The feedback voltage-divider has a gain of GAIN  
=
FB  
V
V
/V  
, where V is 1.0V (typ).  
FB OUT FB  
OUT  
× GAIN  
R
=
C
g
× V  
m, EA  
FB  
MOD(f )  
The transconductance error amplifier has a DC gain of  
GAIN = gm x R , where gm is the  
C
EA(DC)  
,EA  
OUT,EA  
,EA  
Set the error-amplifier compensation zero formed by R  
error-amplifier transconductance, which is 345μS (max),  
C
and C at the f  
lows:  
. Calculate the value of C as fol-  
and R is the output resistance of the error amplifi-  
er, which is 10MΩ (typ). See the Electrical Characteristics  
C
pMOD  
C
OUT,EA  
table.  
1
C
C
=
2π × f  
Adominant pole (f  
itor (CC) and the amplifier output resistance (R  
) is set by the compensation capac-  
× R  
dpEA  
pMOD  
C
). A  
OUT,EA  
zero (f  
) is set by the compensation resistor (RC) and  
ZEA  
If f  
is less than 5 x f , add a second capacitor (C )  
C F  
zMOD  
the compensation capacitor (CC). There is an optional  
from COMP to GND. The value of C is:  
F
pole (f ) set by CF and RC to cancel the output capaci-  
PEA  
tor ESR zero if it occurs near the crossover frequency  
(f ), where the loop gain equals 1 (0dB). Thus:  
C
1
C =  
F
2π × f  
× R  
zMOD  
C
1
f
=
MOSFET Selection  
pEA  
2π × R  
(
+ R × C  
)
OUTEA  
C
C
The key selection parameters to choose the n-channel  
MOSFET used in the boost converter are as follows.  
1
f
=
zEA  
2π × R × C  
C
C
Threshold Voltage  
The boost n-channel MOSFETs must be a logic-level  
1
f
=
p2EA  
type with guaranteed on-resistance specifications at V  
2π × R × C  
GS  
C
F
= 4.5V.  
Maxim Integrated  
17  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Maximum Drain-to-Source Voltage (VDS(MAX))  
Multiphase Operation  
Dual-Phase (MAX25202)  
The MOSFET must be chosen with an appropriate VDS  
rating to handle all VIN voltage conditions.  
Dual-phase operation uses a MAX25202M as the mas-  
ter controller and MAX25202S as the slave. Connect  
these devices as shown in the Dual-Phase Application  
Circuit. In this configuration, the master outputs a clock  
from SYNCOUT that is 180° out-of-phase for driving the  
slave FSYNCINS input. When synchronizing to an exter-  
nal clock, connect the clock to FSYNCIN of the master  
and MODE of the slave. The external clock must have  
50% duty-cycle to ensure the 180° phase shift. To use  
the internal oscillator from the master, drive FSYNCIN  
of the master and MODE of the slave high (connect  
to BIAS). Dual-phase solutions allow spread spectrum  
operation on both the master and slave.  
Current Capability  
The n-channel MOSFET must deliver the input current  
(I  
):  
IN(MAX)  
D
MAX  
×
LOAD(MAX)  
1 − D  
I
= I  
IN(MAX)  
MAX  
Choose MOSFETs with the appropriate average current  
at V = 4.5V.  
GS  
Low Voltage Operation  
The devices start with a supply voltage as low as 4.5V,  
and can operate after initial start up with a supply voltage  
as low as 1.8V. At very low input voltages it is important  
to remember that input current will be high and the power  
components (inductor, MOSFET, and diode) must be  
specified for this higher input current.  
Layout Recommendations  
Careful PCB layout is critical to achieve low switch-  
ing losses and clean, stable operation. Layout of the  
switching power components requires particular attention.  
Follow these guidelines for good PCB layout:  
In addition, the current-limit must be set high enough  
so that the limit is not reached during the MOSFET's on  
time, which would limit output power and eventually force  
the MAX25201/MAX25202 into hiccup mode. Estimate  
the maximum input current using the following equation:  
● Keep high-current paths short, especially at the  
ground terminals.  
● Minimize resistance in high-current paths by keeping  
the traces short and wide. Using thick (2oz vs. 1oz  
copper) improves full load efficiency.  
V
× I  
OUT OUT  
V
− V  
V
OUT  
SUPMIN  
SUPMIN  
● Connect the CS and SUP connections used for cur-  
rent sensing directly across the sense resistor using  
a Kelvin sense connection.  
I
=
+ 0.5 ×  
×
SUPMAX  
η × V  
V
f
× L  
SUPMIN  
OUT  
SW  
where I  
is the maximum input current; V  
and  
SUPMAX  
OUT  
● Route noisy switching and clock traces away from  
sensitive analog areas (FB, CS).  
I
are the output voltage and current, respectively; η  
OUT  
is the estimated efficiency (which is lower at low input  
voltages due to higher resistive losses); V is the  
SUPMIN  
minimum value of the input voltage; f  
is the switching  
SW  
frequency; and L is the minimum value of the chosen  
inductor.  
Maxim Integrated  
18  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Typical Application Circuits  
Synchronous Boost Application Circuit  
BATTERY INPUT  
3.5V TO 36V  
OUTPUT  
BST  
BIAS  
LX  
DL  
MAX25201  
CS  
SUP  
EN  
DH  
OUT  
MODE/  
FSYNC  
FB  
FOSC  
PGOOD  
SS  
C OM P  
GND  
Maxim Integrated  
19  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Typical Application Circuits (continued)  
Dual-Phase Application Circuit  
BATTERY INPUT  
3.5V TO 36V  
OUTPUT  
BST  
BIAS  
LX  
DL  
MAX25202M  
CS  
EXTERNAL CLOCK  
(OPTIONAL)  
SUP  
DH  
OUT  
FB  
FSYNCIN  
FSYNCOUT  
EN  
PGOOD  
GND  
COMP  
SS  
BST  
BIAS  
LX  
DL  
MAX25202S  
CS  
SUP  
DH  
OUT  
COMP  
EN  
FB  
FSYNCINS  
MODE  
GND  
Maxim Integrated  
20  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Ordering Information  
INTERNAL  
SWITCHING  
FREQUENCY  
TEMP  
RANGE  
PIN-  
PACKAGE  
V
FIXED  
SPREAD  
SPECTRUM  
OUT  
PART  
TOPOLOGY  
RANGE  
V
OUT  
-40°C to  
MAX25201ATEA/VY+  
+125°C  
16 SW  
TQFN-EP*  
SINGLE  
PHASE  
3.5V to 36V  
3.5V to 36V  
20V to 60V  
20V to 60V  
20V to 60V  
20V to 60V  
10  
Adjustable  
Adjustable  
Adjustable  
Adjustable  
400kHz  
OFF  
ON  
-40°C to  
MAX25201ATEB/VY+  
+125°C  
16 SW  
TQFN-EP*  
SINGLE  
PHASE  
10  
-40°C to  
MAX25201ATEC/VY+  
+125°C  
16 SW  
TQFN-EP*  
SINGLE  
PHASE  
N/A  
N/A  
N/A  
N/A  
OFF  
ON  
-40°C to  
MAX25201ATED/VY+  
+125°C  
16 SW  
TQFN-EP*  
SINGLE  
PHASE  
-40°C to  
MAX25202MATEA/VY+  
+125°C  
16 SW  
TQFN-EP*  
2-PHASE  
MASTER  
ON  
-40°C to  
MAX25202SATEA/VY+  
+125°C  
16 SW  
TQFN-EP*  
2-PHASE  
SLAVE  
400kHz  
ON  
*EP = Exposed pad.  
Maxim Integrated  
21  
www.maximintegrated.com  
MAX25201/MAX25202  
36V HV Synchronous Boost Controller  
for Automotive Infotainment Applications  
Revision History  
REVISION  
NUMBER  
REVISION  
DATE  
PAGES  
DESCRIPTION  
CHANGED  
0
1
2
3
7/19  
7/19  
Initial release  
Updated Ordering Information section  
21  
12/19  
2/20  
Updated Electrical Chracteristics table and Ordering Information  
Removed remaining future-product notation in Ordering Information  
4. 5, 21  
21  
For information on other Maxim Integrated products, 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.  
2019 Maxim Integrated Products, Inc.  
22  

相关型号:

SI9130DB

5- and 3.3-V Step-Down Synchronous Converters

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9135LG-T1

SMBus Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9135LG-T1-E3

SMBus Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9135_11

SMBus Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9136_11

Multi-Output Power-Supply Controller

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9130CG-T1-E3

Pin-Programmable Dual Controller - Portable PCs

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9130LG-T1-E3

Pin-Programmable Dual Controller - Portable PCs

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9130_11

Pin-Programmable Dual Controller - Portable PCs

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9137

Multi-Output, Sequence Selectable Power-Supply Controller for Mobile Applications

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9137DB

Multi-Output, Sequence Selectable Power-Supply Controller for Mobile Applications

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9137LG

Multi-Output, Sequence Selectable Power-Supply Controller for Mobile Applications

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY

SI9122E

500-kHz Half-Bridge DC/DC Controller with Integrated Secondary Synchronous Rectification Drivers

Warning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY