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  • MAX5020ESA图
  • 深圳市恒达亿科技有限公司

     该会员已使用本站12年以上
  • MAX5020ESA 现货库存
  • 数量4200 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号23+ 
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  • MAX5020ESA+图
  • 深圳市芯脉实业有限公司

     该会员已使用本站11年以上
  • MAX5020ESA+ 现货库存
  • 数量69850 
  • 厂家MAXIM 
  • 封装SOP8 
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  • MAX5020ESA+图
  • 深圳市芯脉实业有限公司

     该会员已使用本站11年以上
  • MAX5020ESA+ 现货库存
  • 数量26980 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号21+ 
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  • MAX5020ESA图
  • 深圳市华斯顿电子科技有限公司

     该会员已使用本站16年以上
  • MAX5020ESA
  • 数量32015 
  • 厂家MAXIM 
  • 封装SO-8 
  • 批号2023+ 
  • 绝对原装正品现货,全新深圳原装进口现货
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  • MAX5020ESA图
  • 北京元坤伟业科技有限公司

     该会员已使用本站17年以上
  • MAX5020ESA
  • 数量5000 
  • 厂家Maxim Integrated Products 
  • 封装贴/插片 
  • 批号2024+ 
  • 百分百原装正品,现货库存
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  • MAX5020ESA+图
  • 集好芯城

     该会员已使用本站13年以上
  • MAX5020ESA+
  • 数量14951 
  • 厂家ADI 
  • 封装Small-Outline IC, Narrow (0.15in) 
  • 批号最新批次 
  • 原厂原装公司现货
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    QQ:3008092965QQ:3008092965 复制
  • 0755-83239307 QQ:3008092965QQ:3008092965
  • MAX5020ESA图
  • 北京齐天芯科技有限公司

     该会员已使用本站15年以上
  • MAX5020ESA
  • 数量5600 
  • 厂家Maxim Integrated 
  • 封装8-SOIC(0.154",3.90mm 宽) 
  • 批号2024+ 
  • 原装正品,假一罚十
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  • 010-62104931 QQ:2880824479QQ:1344056792
  • MAX5020ESA图
  • 北京元坤伟业科技有限公司

     该会员已使用本站17年以上
  • MAX5020ESA
  • 数量5000 
  • 厂家MAX 
  • 封装SO-8 
  • 批号2024+ 
  • 百分百原装正品,现货库存
  • QQ:857273081QQ:857273081 复制
    QQ:1594462451QQ:1594462451 复制
  • 010-62104891 QQ:857273081QQ:1594462451
  • MAX5020ESA图
  • 深圳市美思瑞电子科技有限公司

     该会员已使用本站12年以上
  • MAX5020ESA
  • 数量19455 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号22+ 
  • 市场最低价!原厂原装假一罚十
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  • 0755-83952260 QQ:2885659458QQ:2885657384
  • MAX5020ESA图
  • 深圳市得捷芯城科技有限公司

     该会员已使用本站11年以上
  • MAX5020ESA
  • 数量2897 
  • 厂家MAXIM/美信 
  • 封装NA/ 
  • 批号23+ 
  • 优势代理渠道,原装正品,可全系列订货开增值税票
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  • MAX5020ESA图
  • 上海熠富电子科技有限公司

     该会员已使用本站15年以上
  • MAX5020ESA
  • 数量7700 
  • 厂家MAXIM 
  • 封装N/A 
  • 批号2024 
  • 上海原装现货库存,欢迎查询!
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  • 15821228847 QQ:2719079875QQ:2300949663
  • MAX5020ESA+T图
  • 深圳市毅创腾电子科技有限公司

     该会员已使用本站16年以上
  • MAX5020ESA+T
  • 数量5000 
  • 厂家原装MAXIM 
  • 封装SOP8 
  • 批号22+ 
  • ★只做原装★正品现货★原盒原标★
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  • MAX5020ESA图
  • 深圳市硅诺电子科技有限公司

     该会员已使用本站8年以上
  • MAX5020ESA
  • 数量53961 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号17+ 
  • 原厂指定分销商,有意请来电或QQ洽谈
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  • MAX5020ESA图
  • 深圳市宇集芯电子有限公司

     该会员已使用本站6年以上
  • MAX5020ESA
  • 数量99000 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号23+ 
  • 一级代理进口原装现货、假一罚十价格合理
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  • 0755-2870-8773手机微信同号13430772257 QQ:1157099927QQ:2039672975
  • MAX5020ESA图
  • 深圳市晶美隆科技有限公司

     该会员已使用本站15年以上
  • MAX5020ESA
  • 数量68000 
  • 厂家MAXIM/美信 
  • 封装SOP-8 
  • 批号24+ 
  • 假一罚十,原装进口正品现货供应,价格优势。
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  • 0755-82865294 QQ:198857245
  • MAX5020ESA图
  • 北京耐芯威科技有限公司

     该会员已使用本站13年以上
  • MAX5020ESA
  • 数量5000 
  • 厂家MAXIM 
  • 封装SMD 
  • 批号21+ 
  • 原装正品,公司现货
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  • 86-010-010-62104931 QQ:2880824479QQ:1344056792
  • MAX5020ESA图
  • 北京顺科电子科技有限公司

     该会员已使用本站8年以上
  • MAX5020ESA
  • 数量5500 
  • 厂家MAXIM/美信 
  • 封装SOP-8 
  • 批号21+ 
  • 进口品牌//国产品牌代理商18911556207
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  • MAX5020ESA图
  • 深圳市恒益昌科技有限公司

     该会员已使用本站6年以上
  • MAX5020ESA
  • 数量3200 
  • 厂家MAXIM 
  • 封装SMD 
  • 批号23+ 
  • 全新原装正品现货
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  • MAX5020ESA图
  • 深圳市恒达亿科技有限公司

     该会员已使用本站12年以上
  • MAX5020ESA
  • 数量4200 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号23+ 
  • 全新原装公司现货库存!
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  • MAX5020ESA+T图
  • 深圳市羿芯诚电子有限公司

     该会员已使用本站7年以上
  • MAX5020ESA+T
  • 数量7987 
  • 厂家MAXIM/美信 
  • 封装NA 
  • 批号21+ 
  • 羿芯诚只做原装 原厂渠道 价格优势
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  • 0755-22968581 QQ:2881498351
  • MAX5020ESA+T图
  • 深圳市羿芯诚电子有限公司

     该会员已使用本站7年以上
  • MAX5020ESA+T
  • 数量8800 
  • 厂家MAXIM/美信 
  • 封装原厂封装 
  • 批号新年份 
  • 羿芯诚只做原装,原厂渠道,价格优势可谈!
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  • 0755-82570683 QQ:2853992132
  • MAX5020ESA+图
  • 深圳市芯脉实业有限公司

     该会员已使用本站11年以上
  • MAX5020ESA+
  • 数量69850 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号新批次 
  • 新到现货、一手货源、当天发货、bom配单
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  • 075584507705 QQ:2881512844
  • MAX5020ESA+T图
  • 深圳市科庆电子有限公司

     该会员已使用本站16年以上
  • MAX5020ESA+T
  • 数量1123 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号23+ 
  • 现货只售原厂原装可含13%税
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  • MAX5020ESA+T图
  • 深圳市科雨电子有限公司

     该会员已使用本站9年以上
  • MAX5020ESA+T
  • 数量2500 
  • 厂家MAXIM 
  • 封装SOP-8 
  • 批号24+ 
  • ★体验愉快问购元件!!就找我吧!单价:38元
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  • 133-5299-5145(微信同号) QQ:1415691092
  • MAX5020ESA图
  • 深圳市富科达科技有限公司

     该会员已使用本站13年以上
  • MAX5020ESA
  • 数量24652 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号2020+ 
  • 全新原装特价热卖
  • QQ:1327510916QQ:1327510916 复制
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  • MAX5020ESA图
  • 昂富(深圳)电子科技有限公司

     该会员已使用本站4年以上
  • MAX5020ESA
  • 数量47786 
  • 厂家MAXIM/美信 
  • 封装SOP-8 
  • 批号23+ 
  • 一站式BOM配单,短缺料找现货,怕受骗,就找昂富电子.
  • QQ:GTY82dX7
  • 0755-23611557【陈妙华 QQ:GTY82dX7
  • MAX5020ESA+图
  • 深圳市正信鑫科技有限公司

     该会员已使用本站12年以上
  • MAX5020ESA+
  • 数量5328 
  • 厂家Maxim 
  • 封装原厂封装 
  • 批号22+ 
  • 原装正品★真实库存★价格优势★欢迎来电洽谈
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  • 0755-22655674 QQ:1686616797QQ:2440138151
  • MAX5020ESA图
  • 深圳市欧瑞芯科技有限公司

     该会员已使用本站11年以上
  • MAX5020ESA
  • 数量9500 
  • 厂家Maxim(美信) 
  • 封装8-SOIC(0.154,3.90mm 宽) 
  • 批号24+ 
  • 绝对原装正品,可开专票,欢迎采购!!!
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  • 18565729389 QQ:3354557638QQ:3354557638
  • MAX5020ESA图
  • 深圳市富科达科技有限公司

     该会员已使用本站13年以上
  • MAX5020ESA
  • 数量21688 
  • 厂家MAXIM 
  • 封装原厂特价 
  • 批号2020+ 
  • 全新原装现货库存特价热卖
  • QQ:1220223788QQ:1220223788 复制
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  • MAX5020ESA图
  • 深圳市晶美隆科技有限公司

     该会员已使用本站14年以上
  • MAX5020ESA
  • 数量19759 
  • 厂家MAXIM 
  • 封装SC70 
  • 批号23+ 
  • 全新原装正品现货热卖
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  • MAX5020ESA图
  • 深圳市惊羽科技有限公司

     该会员已使用本站11年以上
  • MAX5020ESA
  • 数量18800 
  • 厂家MAXIM-美信 
  • 封装SOP-8.贴片 
  • 批号▉▉:2年内 
  • ▉▉¥10一一有问必回一一有长期订货一备货HK仓库
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  • 131-4700-5145---Q-微-恭-候---有-问-秒-回 QQ:43871025
  • MAX5020ESA+TG035图
  • 深圳市惊羽科技有限公司

     该会员已使用本站11年以上
  • MAX5020ESA+TG035
  • 数量9328 
  • 厂家MAXIM-美信 
  • 封装车规-控制器IC 
  • 批号▉▉:2年内 
  • ▉▉¥7.3元一有问必回一有长期订货一备货HK仓库
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  • 131-4700-5145---Q-微-恭-候---有-问-秒-回 QQ:43871025
  • MAX5020ESA+图
  • 深圳市惊羽科技有限公司

     该会员已使用本站11年以上
  • MAX5020ESA+
  • 数量6328 
  • 厂家MAXIM-美信 
  • 封装SOP-8.贴片 
  • 批号▉▉:2年内 
  • ▉▉¥34.5元一有问必回一有长期订货一备货HK仓库
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  • 131-4700-5145---Q-微-恭-候---有-问-秒-回 QQ:43871025
  • MAX5020ESA+T图
  • 深圳市欧立现代科技有限公司

     该会员已使用本站12年以上
  • MAX5020ESA+T
  • 数量5000 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号24+ 
  • 全新原装现货,欢迎询购!
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  • MAX5020ESA图
  • 深圳市宇川湘科技有限公司

     该会员已使用本站6年以上
  • MAX5020ESA
  • 数量23000 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号23+ 
  • 原装正品现货,郑重承诺只做原装!
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  • MAX5020ESA+图
  • 深圳市炎凯科技有限公司

     该会员已使用本站7年以上
  • MAX5020ESA+
  • 数量659 
  • 厂家MAXIM 
  • 封装SOP8 
  • 批号24+ 
  • 原装现货
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  • 0755-89587732 QQ:354696650QQ:2850471056

产品型号MAX5020ESA的概述

MAX5020ESA芯片概述 MAX5020ESA是一款由Maxim Integrated公司生产的高效DC-DC转换器,广泛用于电源管理及转换应用。作为一款集成电路,MAX5020ESA在设计上注重性能、效率和热管理,适用于各种要求高的电源系统,如服务器、通信设备和工业自动化设备等。该芯片使用功率MOSFET技术,能在宽输入电压范围内工作,同时具备良好的抗干扰能力和负载适应性。 芯片详细参数 MAX5020ESA具有多个显著的技术参数。此芯片的输入电压范围为4.5V至28V,输出电压可通过外部电阻进行设定,通常在1.25V到20V之间。其最大输出电流可以达到3A,同时具有相对较小的静态电流,这使得该芯片非常适合电池供电的应用。转换效率高达90% ,这使得它在提高电能利用率方面具有优势。 在频率参数方面,MAX5020ESA的开关频率在200kHz至1MHz之间可调,允许设计师通过调节...

产品型号MAX5020ESA的Datasheet PDF文件预览

19-2115; Rev 0; 7/01  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
General Description  
Features  
o Wide Input Range: (18V to 110V) or (13V to 36V)  
The MAX5019/MAX5020 integrate all the building  
blocks necessary for implementing DC-DC fixed-fre-  
quency power supplies. Either primary- or secondary-  
side regulation may be used to implement isolated or  
nonisolated power supplies. These devices are current-  
mode controllers with an integrated high-voltage start-  
up circuit suitable for telecom/industrial voltage range  
power supplies. Current-mode control with leading-  
edge blanking simplifies control-loop design and inter-  
nal ramp compensation circuitry stabilizes the current  
loop when operating at duty cycles above 50%  
(MAX5019). The MAX5019 allows 85% operating duty  
cycle and can be used to implement flyback converters  
whereas the MAX5020 limits the operating duty cycle to  
less than 50% and can be used in single-ended for-  
ward converters. A high-voltage startup circuit allows  
these devices to draw power directly from the 18V to  
110V input supply during startup. The switching fre-  
quency is internally trimmed to 275kHz 10%ꢀ thus  
reducing magnetics and filter component costs.  
o Isolated (without optocoupler) or Nonisolated  
Power Supply  
o Current-Mode Control  
o Leading-Edge Blanking  
o Internally Trimmed 275kHz 10ꢀ ꢁscillator  
o Low External Component Count  
o Soft-Start  
o High-Voltage Startup Circuit  
o Pulse-by-Pulse Current Limiting  
o Thermal Shutdown  
o Sꢁ-8 Package  
Ordering Information  
The MAX5019/MAX5020 are available in 8-pin SO  
packages.  
PART  
TEMP. RANGE  
0°C to +70°C  
PIN-PACKAGE  
8-SO  
MAX5019CSA*  
MAX5019ESA*  
MAX5020CSA*  
MAX5020ESA*  
Warning: The MAX5019/MAX5020 operate with high  
voltages. Exercise caution.  
-40°C to +85°C  
0°C to +70°C  
8-SO  
8-SO  
Applications  
-40°C to +85°C  
8-SO  
*See Selector Guide at end of data sheet.  
Telecom Power Supplies  
Industrial Power Supplies  
Networking Power Supplies  
Isolated Power Supplies  
Typical Operating Circuit  
Pin Configuration  
V
IN  
V
OUT  
V+  
TOP VIEW  
V
V
DD  
MAX5020  
V+  
1
2
3
4
8
7
6
5
V
CC  
NDRV  
CS  
CC  
V
NDRV  
GND  
CS  
DD  
FB  
MAX5019/  
MAX5020  
SS_SHDN  
GND  
FB  
SS_SHDN  
8-Sꢁ  
________________________________________________________________ Maxim Integrated Products  
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at  
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
ABSꢁLUTE MAXIMUM RATINGS  
V+ to GND…………………………………...……-0.3V to +120V  
Continuous Power Dissipation (T = +70°C)  
A
V
V
to GND.………………………………….……….-0.3V to +40V  
to GND.………………….……………………-0.3V to +12.5V  
8-Pin SO (derate 5.88mW/°C above +70°C).………....471mW  
Operating Temperature Range…………..……...-40°C to +85°C  
Storage Temperature Range……………..…….-65°C to +150°C  
Lead Temperature (solderingꢀ 10s) …………………+300°C  
DD  
CC  
FBꢀ NDRVꢀ SS_SHDNꢀ CS to GND .……-0.3V to V  
V
+ 0.3V  
CC  
and V  
Current …………………...…………………..20mA  
DD  
CC  
NDRV Current Continuous...………………………………….25mA  
NDRV Current for Less than 1µs..………….…………….…… 1A  
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional  
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to  
absolute maximum rating conditions for extended periods may affect device reliability.  
ELECTRICAL CHARACTERISTICS  
(V  
= 13Vꢀ a 10µF capacitor connects V  
to GNDꢀ V = 0ꢀ V+ = 48Vꢀ 0.1µF capacitor connected from SS_SHDN to GNDꢀ NDRV  
DD  
CC CS  
= open circuitꢀ V = 3Vꢀ T = -40°C to +85°Cꢀ unless otherwise noted. Typical values are at T = +25°C.)  
FB  
A
A
PARAMETER  
SYMBꢁL  
CꢁNDITIꢁNS  
MIN  
TYP  
MAX  
UNITS  
SUPPLY CURRENT  
I
V
= 0, V+ = 110V, driver not switching  
DD  
0.8  
1.6  
1.6  
3.0  
V+(NS)  
V+ Supply Current  
mA  
V+ = 110V, V  
driver switching  
V+ = 110V, V  
= 0, FB = GND,  
DD  
I
V+(S)  
V+ Supply Current After Startup  
Supply Current  
= 13V, FB = GND  
14  
0.9  
2.1  
180  
4
µA  
DD  
I
V
V
V
V
= 36V, driver not switching  
1.6  
3.0  
290  
20  
VDD(NS)  
DD  
V
mA  
DD  
I
= 36V, driver switching, FB = GND  
VDD(S)  
DD  
V+ Shutdown Current  
Shutdown Current  
= 0, V+ = 110V  
= 0  
µA  
µA  
SS_SHDN  
SS_SHDN  
V
DD  
PREREGULATꢁR/STARTUP  
V+ Input Voltage  
18  
13  
110  
36  
V
V
V
Supply Voltage  
DD  
INTERNAL REGULATꢁRS (V  
)
CC  
Powered from V+, I  
= 7.5mA, V  
= 0  
DD  
7.5  
9.0  
9.8  
10.0  
6.6  
12.0  
11.0  
V
V
V
CC  
V
Output Voltage  
CC  
Powered from V , I  
= 7.5mA  
DD CC  
V
Undervoltage Lockout  
V
V
falling  
CC  
CC  
CC_UVLO  
ꢁUTPUT DRIVER  
Peak Source Current  
Peak Sink Current  
V
V
= 11V (externally forced)  
= 11V (externally forced)  
570  
mA  
mA  
CC  
CC  
1000  
NRDV High-Side Driver  
Resistance  
V
= 11V, externally forced,  
CC  
R
4
12  
4
OH  
NDRV sourcing 50mA  
NDRV Low-Side Driver  
Resistance  
V
CC  
= 11V, externally forced,  
R
1.6  
OL  
NDRV sinking 50mA  
ERRꢁR AMPLIFIER  
FB Input Resistance  
FB Input Bias Current  
R
50  
1
kΩ  
µA  
V/V  
kHz  
V
IN  
I
FB  
V
V
FB = SS_SHDN  
Error Amplifier Gain (Inverting)  
Closed-Loop 3dB Bandwidth  
FB Input Voltage Range  
A
VCL  
-20  
200  
2
3
2
_______________________________________________________________________________________  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
ELECTRICAL CHARACTERISTICS (continued)  
(V  
= 13V, a 10µF capacitor connects V  
to GND, V = 0, V+ = 48V, 0.1µF capacitor connected from SS_SHDN to GND, NDRV  
DD  
CC CS  
= open circuit, V = 3V, T = -40°C to +85°C, unless otherwise noted. Typical values are at T = +25°C.)  
FB  
A
A
PARAMETER  
SYMBꢁL  
CꢁNDITIꢁNS  
MIN  
TYP  
MAX  
UNITS  
SLꢁPE CꢁMPENSATIꢁN  
Slope Compensation  
(MAX5019 only)  
V
26  
mV/µs  
SCOMP  
THERMAL SHUTDꢁWN  
Thermal Shutdown Temperature  
Thermal Hysteresis  
150  
25  
°C  
°C  
CURRENT LIMIT  
CS Threshold Voltage  
CS Input Bias Current  
V
FB = GND  
419  
-1  
465  
510  
1
mV  
ILIM  
0 V 2V, FB = GND  
µA  
CS  
Current Limit Comparator  
Propagation Delay  
50mV overdrive on CS, FB = GND  
180  
70  
ns  
ns  
CS Blanking Time  
ꢁSCILLATꢁR  
FB = GND, only PWM comparator is blanked  
Clock Frequency Range  
FB = GND  
247  
75  
275  
302  
85  
kHz  
%
MAX5019, FB = GND  
MAX5020, FB = GND  
Max Duty Cycle  
44  
50  
SꢁFT-START  
SS Source Current  
SS Sink Current  
I
V
= 0  
SS_SHDN  
2.0  
1.0  
4.5  
6.5  
µA  
SSO  
mA  
Steady State Reference Voltage  
at SS_SHDN  
V
_SHDN No external load  
2.331  
2.420  
2.500  
V
V
SS  
V
V
falling  
rising  
0.25  
0.53  
0.37  
0.59  
0.41  
0.65  
SS_SHDN  
SS_SHDN  
Shutdown Threshold  
Typical Operating Characteristics  
= 13V, CS = GND, NRDV is open circuit, T = +25°C, unless otherwise noted.)  
A
(V+ = 48V, V  
DD  
MAX5019  
MAXIMUM DUTY CYCLE  
vs. TEMPERATURE  
V
vs. TEMPERATURE  
NDRV FREQUENCY  
vs. TEMPERATURE  
SS_SHDN  
(AT THE END OF SOFT-START)  
1.003  
1.002  
1.001  
1.000  
278  
277  
276  
275  
274  
273  
81.0  
80.9  
80.8  
80.7  
80.6  
80.5  
80.4  
V
= 4V  
FB  
FB = GND  
FB = GND  
0.999  
-40  
-20  
0
20  
40  
60  
80  
-40  
-20  
0
20  
40  
60  
80  
-40  
-20  
0
20  
40  
60  
80  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
_______________________________________________________________________________________  
3
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
Typical Operating Characteristics (continued)  
(V+ = 48V, V  
= 13V, CS = GND, NRDV is open circuit, T = +25°C, unless otherwise noted.)  
DD  
A
MAX5020  
MAXIMUM DUTY CYCLE  
vs. TEMPERATURE  
V+ SUPPLY CURRENT  
vs. TEMPERATURE  
SOFT-START SOURCE CURRENT  
vs. TEMPERATURE  
1.64  
1.63  
1.62  
4.50  
4.49  
4.48  
4.47  
4.46  
4.45  
4.44  
4.43  
4.42  
4.41  
4.40  
48.0  
47.8  
47.6  
47.4  
47.2  
47.0  
46.8  
V
= FB = SS_SHDN = GND  
DD  
FB = GND  
V+ = 110V  
FB = V = GND  
DD  
1.61  
1.60  
1.59  
1.58  
1.57  
1.56  
1.55  
-40  
-20  
0
20  
60  
80  
-40  
-40  
0
-20  
0
20  
40  
60  
80  
40  
-40  
-40  
-40  
-20  
0
20  
40  
60  
80  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
V+ SHUTDOWN CURRENT  
vs. TEMPERATURE  
V+ INPUT CURRENT vs.  
TEMPERATURE (AFTER STARTUP)  
CS THRESHOLD VOLTAGE  
vs. TEMPERATURE  
182.5  
182.0  
0.488  
0.487  
0.486  
0.485  
0.484  
0.483  
13.80  
13.75  
13.70  
13.65  
V+ = 110V, FB = SS_SHDN = GND  
FB = GND  
V+ = 110V, V = 13V, FB = GND  
DD  
181.5  
181.0  
180.5  
180.0  
179.5  
179.0  
13.60  
13.55  
13.50  
-40  
-20  
0
20  
40  
60  
80  
-20  
0
20  
40  
60  
80  
-20  
0
20  
40  
60  
80  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
NDRV RESISTANCE  
vs. TEMPERATURE  
CURRENT-LIMIT DELAY  
vs. TEMPERATURE  
V
vs. V  
DD  
SS_SHDN  
5.0  
4.5  
4.0  
3.5  
3.0  
2.410  
2.408  
2.406  
2.404  
2.402  
2.400  
210  
208  
206  
204  
202  
200  
198  
196  
194  
192  
190  
188  
FB = GND, 100mV OVERDRIVE ON CS  
HIGH-SIDE DRIVER  
LOW-SIDE DRIVER  
2.5  
2.0  
1.5  
1.0  
-20  
0
20  
60  
80  
40  
5
10 15 20 25 30 35 40  
(V)  
-40  
-20  
0
20  
40  
60  
80  
TEMPERATURE (°C)  
V
DD  
TEMPERATURE (°C)  
4
_______________________________________________________________________________________  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
Typical Operating Characteristics (continued)  
(V+ = 48V, V  
= 13V, CS = GND, NRDV is open circuit, T = +25°C, unless otherwise noted.)  
DD  
A
MAX5020  
MAXIMUM DUTY CYCLE vs. V  
DD  
V
vs. V  
DD  
NDRV FREQUENCY vs. V  
CC  
DD  
48.0  
47.9  
47.8  
47.7  
47.6  
47.5  
47.4  
47.3  
47.2  
47.1  
47.0  
271.0  
270.5  
270.0  
269.5  
269.0  
268.5  
268.0  
267.5  
10.2  
10.1  
10.0  
9.9  
V
FB  
= 4V, CS = GND  
DEVICE POWERED FROM V  
DD  
FB = GND  
DEVICE POWERED  
9.8  
FROM V  
DD  
FB = GND  
9.7  
DEVICE POWERED  
FROM V+  
9.6  
DEVICE POWERED  
FROM V+  
9.5  
267.0  
0
0
5
10 15 20 25 30 35 40  
(V)  
5
10 15 20 25 30 35 40  
(V)  
0
5
10 15 20 25 30 35 40  
(V)  
V
DD  
V
DD  
V
DD  
V+ SUPPLY CURRENT vs. V+ VOLTAGE  
(AFTER STARTUP)  
V+ SUPPLY CURRENT vs.  
V+ VOLTAGE  
16  
14  
12  
10  
8
1.60  
1.59  
1.58  
1.57  
1.56  
1.55  
1.54  
1.53  
1.52  
1.51  
V
= 13V, FB = GND  
V
= V = GND  
DD  
DD  
FB  
6
4
2
0
0
10 20 30 40 50 60 70 80 90 100 110  
V+ VOLTAGE (V)  
0
20  
40  
60  
80  
100  
V+ VOLTAGE (V)  
V
VOLTAGE vs. V CURRENT  
V
VOLTAGE vs. V CURRENT  
CC  
CC  
CC  
CC  
10.0  
9.9  
9.8  
9.7  
9.6  
9.5  
9.4  
9.3  
9.2  
9.1  
9.0  
10.4  
10.2  
10.0  
9.8  
V
DD  
= GND, V = 4V  
V+ = 110V, V = 4V  
FB  
FB  
V+ = 110V  
V+ = 90V  
V+ = 72V  
V+ = 48V  
V
DD  
= 36V  
V
DD  
= 13V  
V+ = 36V  
V+ = 24V  
9.6  
9.4  
9.2  
9.0  
0
5.0  
10.0  
15.0  
20.0  
0
5.0  
10.0  
CURRENT (mA)  
15.0  
20.0  
V
CC  
V
CC  
CURRENT (mA)  
_______________________________________________________________________________________  
5
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
Pin Description  
PIN  
NAME  
FUNCTIꢁN  
High-Voltage Startup Input. Connect directly to an input voltage between 18V to 110V. Connects  
1
V+  
internally to a high-voltage linear regulator that generates V  
during startup.  
CC  
V
is the Input of the Linear Regulator that Generates V . For supply voltages less than 36V, V  
CC DD  
DD  
and V+ can both be connected to the supply. For supply voltages greater than 36V, V  
its power from the tertiary winding of the transformer and accepts voltages from 13V to 36V. Bypass  
to GND with a 4.7µF capacitor.  
receives  
DD  
2
V
DD  
Input of the Fixed-Gain Inverting Amplifier. Connect a voltage-divider from the regulated output to  
this pin. The noninverting input of the amplifier is referenced to 2.4V.  
3
4
FB  
Soft-Start Timing Capacitor Connection. Ramp time to full current limit is approximately 0.45ms/nF.  
This pin is also the reference voltage output. Bypass with a minimum 10nF capacitor to GND. The  
device goes into shutdown when SS_SHDN is pulled below 0.25V.  
SS_SHDN  
Current Sense Input. Turns power switch off if V rises above 465mV for cycle-by-cycle current  
CS  
limiting. CS is also the feedback for the current-mode controller. CS is connected to the PWM  
comparator through a leading-edge blanking circuit.  
5
CS  
6
7
GND  
Ground  
NDRV  
Gate Drive. Drives a high-voltage external N-channel power MOSFET.  
Regulated IC Supply. Provides power for the entire IC. V is regulated from V  
during normal  
CC  
DD  
8
V
operation and from V+ during startup. Bypass V with a 10µF tantalum capacitor in parallel with  
CC  
CC  
0.1µF ceramic capacitor to GND.  
sensed current signal applied to the input of the PWM  
comparator. The current limit comparator monitors the  
Detailed Description  
Use the MAX5019/MAX5020 PWM current-mode con-  
trollers to design flyback- or forward-mode power sup-  
plies. Current-mode operation simplifies control-loop  
design while enhancing loop stability. An internal high-  
voltage startup regulator allows the device to connect  
directly to the input supply without an external startup  
resistor. Current from the internal regulator starts the  
controller. Once the tertiary winding voltage is estab-  
lished the internal regulator is switched off and bias  
current for running the IC is derived from the tertiary  
winding. The internal oscillator is set to 275kHz and  
trimmed to 10%. This permits the use of small mag-  
netic components to minimize board space. Both the  
MAX5019 and MAX5020 can be used in power sup-  
plies providing multiple output voltages. A functional  
diagram of the IC is shown in Figure 1. Typical applica-  
tions circuits for forward and flyback topologies are  
shown in Figure 2 and Figure 3, respectively. For isolat-  
ed flyback power supplies use the circuit of Figure 4.  
CS pin at all times and provides cycle-by-cycle current  
limit without being blanked. The leading-edge blanking  
of the CS signal prevents the PWM comparator from  
prematurely terminating the on cycle. The CS signal  
contains a leading-edge spike that is the result of the  
MOSFET gate charge current, capacitive and diode  
reverse recovery current of the power circuit. Since this  
leading-edge spike is normally lower than the current  
limit comparator threshold, current limiting is not  
blanked and cycle-by-cycle current limiting is provided  
under all conditions.  
Use the MAX5019 in discontinuous flyback applications  
where wide line voltage and load current variation is  
expected. Use the MAX5020 for single transistor for-  
ward converters where the maximum duty cycle must  
be limited to less than 50%.  
Under certain conditions it may be advantageous to  
use a forward converter with greater than 50% duty  
cycle. For those cases use the MAX5019. The large  
duty cycle results in much lower operating primary  
RMS currents through the MOSFET switch and in most  
cases a smaller output filter inductor. The major disad-  
Current-Mode Control  
The MAX5019/MAX5020 offer current-mode control  
operation with added features such as leading-edge  
blanking with dual internal path that only blanks the  
6
_______________________________________________________________________________________  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
V
DD  
V
DD-OK  
V+  
IN  
IN  
HIGH-  
VOLTAGE  
REGULATOR  
BIAS  
WINDING  
REGULATOR  
GND  
EN  
EN  
OUT  
OUT  
0.7V  
V
CC  
MAX5019 ONLY  
UVLO  
6.6V  
SLOPE  
COMPENSATION  
26mV/µs  
V
CC  
275kHz  
R
S
OSCILLATOR  
NDRV  
Q
26mV/µs  
1MΩ  
80%/50%  
DUTY CYCLE  
CLAMP  
50kΩ  
FB  
ILIM  
70ns  
PWM  
125mV  
CS  
ERROR  
AMP  
5kΩ  
V
CC  
BLANKING  
SS_SHDN  
4µA  
3R  
2.4V  
BUF  
R
0.25V  
Figure 1. Functional Diagram  
_______________________________________________________________________________________  
7
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
1N4148  
N
N
R
T
6
L1  
4.7µH  
14  
CMHD2003  
V
V
IN  
SBL204OCT  
OUT  
5V/10A  
(36V TO 72V)  
C
IN  
3
C
3
OUT  
V+  
V
V
DD  
CC  
0.47µF  
20Ω  
560µF  
N
N
S
5
P
C
DD  
4.7µF  
14  
0.1µF  
1nF  
M1  
MAX5020  
IRF640N  
NDRV  
CS  
C
R
CC  
10µF  
1
2kΩ  
100Ω  
R
SENSE  
100mΩ  
SS_SHDN  
C
SS  
0.1µF  
GND  
FB  
R
2
C
FB  
2kΩ  
(OPTIONAL)  
Figure 2. Forward Converter  
vantage to this is that the MOSFET voltage rating must  
be higher and that slope compensation must be provid-  
ed to stabilize the inner current loop. The MAX5019  
provides internal slope compensation.  
abled, and soft-start is reinitiated. In undervoltage lock-  
out the MOSFET driver output (NDRV) is held low.  
If the input voltage range is between 13V and 36V, V+  
and V  
may be connected to the line voltage provid-  
DD  
ed that the maximum power dissipation is not exceed-  
ed. This eliminates the need for a tertiary winding.  
Internal Regulators  
The internal regulators of the MAX5019/MAX5020  
enable initial startup without a lossy startup resistor and  
regulate the voltage at the output of a tertiary (bias)  
winding to provide power for the IC. At startup V+ is  
Undervoltage Lockout (UVLO), Soft-Start,  
and Shutdown  
The soft-start feature of the MAX5019/MAX5020 allows  
the load voltage to ramp up in a controlled manner,  
thus eliminating output voltage overshoot.  
regulated down to V  
to provide bias for the device.  
CC  
The V  
regulator then regulates from the output of the  
DD  
tertiary winding to V . This architecture allows the ter-  
CC  
While the part is in UVLO, the capacitor connected to  
the SS_SHDN pin is discharged. Upon coming out of  
UVLO an internal current source starts charging the  
capacitor to initiate the soft-start cycle. Use the follow-  
ing equation to calculate total soft-start time:  
tiary winding to only have a small filter capacitor at its  
output thus eliminating the additional cost of a filter  
inductor.  
When designing the tertiary winding calculate the num-  
ber of turns so the minimum reflected voltage is always  
higher than 12.7V. The maximum reflected voltage  
must be less than 36V.  
ms  
nF  
tstartup = 0.45  
×Css  
To reduce power dissipation the high-voltage regulator  
is disabled when the V  
voltage reaches 12.7V. This  
DD  
where C is the soft-start capacitor as shown in Figure 2.  
SS  
greatly reduces power dissipation and improves effi-  
Operation begins when V  
ramps above 0.6V.  
SS_SHDN  
SS_SHDN  
When soft-start has completed, V  
ciency. If V  
falls below the undervoltage lockout  
= 6.6V), the low-voltage regulator is dis-  
CC  
CC  
is regulated  
threshold (V  
8
_______________________________________________________________________________________  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
N
T
V
OUT  
V
IN  
C
OUT  
C
IN  
V+  
V
V
DD  
N
P
N
S
C
C
DD  
MAX5019  
MAX5020  
CC  
M1  
NDRV  
CS  
CC  
100Ω  
SS_SHDN  
R
SENSE  
R
R
1
C
SS  
GND  
FB  
2
Figure 3. Nonisolated Flyback Converter  
N
T
V
OUT  
V
IN  
C
OUT  
C
IN  
V+  
V
DD  
N
P
N
S
C
DD  
R
R
1
MAX5019  
MAX5020  
FB  
M1  
NDRV  
CS  
2
V
CC  
C
CC  
100Ω  
R
SENSE  
SS_SHDN  
GND  
C
SS  
Figure 4. Isolated Flyback Converter  
to 2.4V, the internal voltage reference. Pull V  
below 0.25V to disable the controller.  
Current-Sense Comparator  
SS_SHDN  
The current-sense (CS) comparator and its associated  
logic limit the peak current through the MOSFET.  
Current is sensed at CS as a voltage across a sense  
resistor between the source of the MOSFET and GND.  
To reduce switching noise, connect CS to the external  
MOSFET source through a 100resistor or an RC low-  
Undervoltage lockout shuts down the controller when  
is less than 6.6V. The regulators for V+ and the ref-  
V
CC  
erence remain on during shutdown.  
_______________________________________________________________________________________  
9
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
pass filter (Figures 2, 3). Select the current-sense resis-  
switch the N-channel MOSFET off. In normal operation  
the N-channel MOSFET turns off when:  
tor, R  
according to the following equation:  
SENSE  
I
× R  
> V - V  
- V  
PRIMARY  
SENSE  
EA  
REF SCOMP  
RSENSE = 0.465V/ILimPrimary  
where I  
is the current through the N-channel  
PRIMARY  
MOSFET, V  
is the 2.4V internal reference, V is the  
REF  
EA  
where I  
current.  
is the maximum peak primary-side  
LimPrimary  
output voltage of the internal amplifier, and V  
is  
SCOMP  
a ramp function starting at 0 and slewing at 26mV/µs  
(MAX5019 only). When using the MAX5019 in a for-  
ward-converter configuration the following condition  
must be met to avoid control-loop subharmonic oscilla-  
tions:  
When V  
> 465mV, the power MOSFET switches off.  
CS  
The propagation delay from the time the switch current  
reaches the trip level to the driver turn-off time is 180ns.  
Internal Error Amplifier  
The MAX5019/MAX5020 include an internal error ampli-  
fier that can be used to regulate the output voltage in  
the case of a nonisolated power supply (see Figure 2).  
Calculate the output voltage using the following equa-  
tion:  
NS k ×RSENSE × VOUT  
×
= 26mV/µs  
NP  
L
where k = 0.75 to 1, and N and N are the number of  
S
P
turns on the secondary and primary side of the trans-  
former, respectively. L is the output filter inductor. This  
makes the output inductor current downslope as refer-  
R1  
R
VOUT = 1+  
× VREF  
2   
enced across R  
equal to the slope compensa-  
SENSE  
tion. The controller responds to transients within one  
cycle when this condition is met.  
where V  
= 2.4V.  
REF  
Choose R //R << R , where R , 50kis the input  
resistance of FB. The gain of the error amplifier is inter-  
nally configured for -20 (see Figure 1).  
1
2
IN  
IN  
N-Channel MOSFET Gate Driver  
NDRV drives an N-channel MOSFET. NDRV sources  
and sinks large transient currents to charge and dis-  
charge the MOSFET gate. To support such switching  
The error amplifier may also be used to regulate the out-  
put of the tertiary winding for implementing a primary-  
side regulated isolated power supply (see Figure 4).  
Calculate the output voltage using the following equation:  
transients, bypass V  
with a ceramic capacitor. The  
CC  
average current as a result of switching the MOSFET is  
the product of the total gate charge and the operating  
frequency. It is this current plus the DC quiescent cur-  
rent that determines the total operating current.  
NS  
NT  
R1  
R
VOUT  
=
1+  
× VREF  
2   
Applications Information  
Design Example  
The following is a general procedure for designing a  
forward converter using the MAX5020.  
where N is the number of secondary turns and N is  
the number of tertiary winding turns.  
S
T
PWM Comparator and Slope Compensation  
An internal 275kHz oscillator determines the switching  
frequency of the controller. At the beginning of each  
cycle, NDRV switches the N-channel MOSFET on.  
NDRV switches the external MOSFET off after the maxi-  
mum duty cycle has been reached, regardless of the  
feedback.  
1) Determine the requirements.  
2) Set the output voltage.  
3) Calculate the transformer primary to secondary  
winding turns ratio.  
4) Calculate the reset to primary winding turns ratio.  
The MAX5019 uses an internal ramp generator for  
slope compensation. The internal ramp signal is reset  
at the beginning of each cycle and slews at 26mV/µs.  
5) Calculate the tertiary to primary winding turns  
ratio.  
6) Calculate the current-sense resistor value.  
7) Calculate the output inductor value.  
8) Select the output capacitor.  
The PWM comparator uses the instantaneous current,  
the error voltage, the internal reference, and the slope  
compensation (MAX5019 only) to determine when to  
The circuit in Figure 2 was designed as follows:  
10 ______________________________________________________________________________________  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
1) 36V V 72V, V  
= 5V, I  
= 10A, V ≤  
RIPPLE  
of a forward converter is not delivered to the load  
and must be returned back to the input; this is  
accomplished with the reset winding.  
IN  
OUT  
OUT  
50mV  
2) To set the output voltage calculate the values of  
resistors R1 and R2 according to the following  
equation:  
The transformer primary to secondary leakage  
inductance should be less than 1µH. Note that all  
leakage energy will be dissipated across the MOS-  
FET. Snubber circuits may be used to direct some or  
all of the leakage energy to be dissipated across a  
resistor.  
R1  
VOUT VREF 1+  
R
2   
R1//R2 << 50kΩ  
VREF = VSS_SHDN 2.4V  
To calculate the minimum duty cycle (D  
following equation:  
) use the  
MIN  
V
OUT  
D
=
where V  
is the reference voltage of the shunt  
MIN  
REF  
N
S
regulator, and R and R are the resistors shown in  
1
2
V
×
- V  
D1  
IN_MAX  
N
Figures 2 and 3.  
P
3) The turns ratio of the transformer is calculated based  
on the minimum input voltage and the lower limit of  
the maximum duty cycle for the MAX5020 (44%). To  
enable the use of MOSFETs with drain-source  
breakdown voltages of less than 200V use the  
MAX5020 with the 50% maximum duty cycle.  
Calculate the turns ratio according to the following  
equation:  
where V  
is the maximum input voltage (72V).  
IN_MAX  
4) The reset winding turns ratio (N /N ) needs to be  
R
P
low enough to guarantee that the entire energy in  
the transformer is returned to V+ within the off cycle  
at the maximum duty cycle. Use the following equa-  
tion to determine the reset winding turns ratio:  
1-DMAX  
NR NP ×  
VOUT + VD1 ×DMAX  
(
)
NS  
NP  
DMAX  
DMAX × V  
IN_MIN  
where:  
N /N = Reset winding turns ratio.  
where:  
N /N = Turns ratio (N is the number of secondary  
R
P
D = Maximum value of Maximum Duty Cycle.  
MAX  
S
P
S
turns and N is the number of primary turns).  
P
V
= Output voltage (5V).  
OUT  
1-0.5  
0.5  
NR 14×  
=14  
V
= Voltage drop across D1 (typically 0.5V for  
D1  
power Schottky diodes).  
D
= Minimum value of maximum operating duty  
MAX  
cycle (44%).  
Round N to the nearest smallest integer.  
R
The turns ratio of the reset winding (N /N ) will  
determine the peak voltage across the N-channel  
MOSFET.  
R
P
V
= Minimum Input voltage (36V).  
IN_MIN  
In this example:  
Use the following equation to determine the maxi-  
mum drain-source voltage across the N-channel  
MOSFET:  
5V+ 0.5V × 0.44  
(
)
NS  
= 0.330  
NP  
0.44× 36V  
NP  
N
R   
VDSMAX VIN_MAX × 1 +  
Choose N based on core losses and DC resis-  
P
tance. Use the turns ratio to calculate N , rounding  
S
up to the nearest integer. In this example N = 14  
P
V
V
= Maximum MOSFET drain-source voltage.  
= Maximum input voltage.  
DSMAX  
and N = 5.  
S
IN_MAX  
For a forward converter choose a transformer with a  
magnetizing inductance in the neighborhood of  
200µH. Energy stored in the magnetizing inductance  
______________________________________________________________________________________ 11  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
7) Choose the inductor value so that the peak ripple  
14  
14  
current (LIR) in the inductor is between 10% and  
20% of the maximum output current.  
VDSMAX 72V × 1 +  
=144V  
V
OUT + VD × 1-D  
(
)
(
)
MIN  
Choose MOSFETs with appropriate avalanche  
power ratings.  
L ≥  
2×LIR×275kHz×IOUTMAX  
5) Choose the tertiary winding turns ratio (N /N ) so  
T
P
where V is the output Schottky diode forward volt-  
D
age drop (0.5V).  
that the minimum input voltage provides the mini-  
mum operating voltage at V (13V). Use the follow-  
DD  
ing equation to calculate the tertiary winding turns  
ratio:  
5.5 × 1-0.198  
0.4×275kHz×10A  
(
)
(
)
L ≥  
= 4.01µH  
VDDMIN + 0.7  
× NP NT ≤  
8) The size and ESR of the output filter capacitor deter-  
mine the output ripple. Choose a capacitor with a  
low ESR to yield the required ripple voltage.  
V
IN_MIN  
VDDMAX + 0.7  
× NP  
V
IN_MAX  
Use the following equations to calculate the peak-to-  
peak output ripple:  
where:  
VRIPPLE = VR2IPPLE,ESR + VR2IPPLE,C  
V
is the minimum V supply voltage (13V).  
DD  
DDMIN  
V
V
V
is the maximum V  
supply voltage (36V).  
DD  
DDMAX  
IN_MIN  
IN_MAX  
where:  
is the minimum input supply voltage (36V).  
is the maximum input supply voltage (72V  
in this design example).  
V
is the combined RMS output ripple due to  
RIPPLE  
VRIPPLE,ESR, the ESR ripple, and V  
, the  
RIPPLE,C  
capacitive ripple. Calculate the ESR ripple and  
capacitive ripple as follows:  
N is the number of turns of the primary winding.  
P
N is the number of turns of the tertiary winding.  
T
V
V
= I  
x ESR  
RIPPLE  
RIPPLE,ESR  
RIPPLE,C  
= I  
/(2 x π x 275kHz x C  
)
OUT  
13.7  
36  
36.7  
72  
RIPPLE  
×14NT ≤  
×14  
5.33NT 7.14  
Layout Recommendations  
Choose N = 6.  
T
All connections carrying pulsed currents must be very  
short, be as wide as possible, and have a ground plane  
as a return path. The inductance of these connections  
must be kept to a minimum due to the high di/dt of the  
currents in high-frequency switching power converters.  
6) Choose R  
according to the following equation:  
SENSE  
V
ILIM  
RSENSE  
NS  
NP  
×1.2×IOUTMAX  
Current loops must be analyzed in any layout pro-  
posed, and the internal area kept to a minimum to  
reduce radiated EMI. Ground planes must be kept as  
intact as possible.  
where:  
V
ILim  
is the current-sense comparator trip threshold  
voltage (0.465V).  
N /N is the secondary side turns ratio (5/14 in this  
Chip Information  
TRANSISTOR COUNT: 589  
S
P
example).  
I
is the maximum DC output current (10A in  
OUTMAX  
this example).  
PROCESS: BiCMOS  
0.465V  
RSENSE  
=109mΩ  
5
×1.2×10  
14  
12 ______________________________________________________________________________________  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
Table 1. Component Manufacturers  
International Rectifier  
Fairchild  
www.irf.com  
Power FETS  
www.fairchildsemi.com  
www.vishay.com/brands/siliconix/main.html  
www.vishay.com/brands/dale/main.html  
www.irctt.com/pages/index.cfm  
www.onsemi.com  
Vishay-Siliconix  
Dale-Vishay  
IRC  
Current-Sense Resistors  
Diodes  
On Semi  
General Semiconductor  
Central Semiconductor  
Sanyo  
www.gensemi.com  
www.centralsemi.com  
www.sanyo.com  
Capacitors  
Magnetics  
Taiyo Yuden  
AVX  
www.t-yuden.com  
www.avxcorp.com  
Coiltronics  
www.cooperet.com  
Coilcraft  
www.coilcraft.com  
Pulse Engineering  
www.pulseeng.com  
Selector Guide  
MAXIMUM  
DUTY CYCLE  
SLꢁPE  
CꢁMPENSATIꢁN  
PART  
MAX5019CSA  
MAX5019ESA  
MAX5020CSA  
MAX5020ESA  
85%  
85%  
50%  
50%  
Yes  
Yes  
No  
No  
______________________________________________________________________________________ 13  
Current-Mode PWM Controllers with Integrated  
Startup Circuit  
Package Information  
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are  
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.  
14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600  
© 2001 Maxim Integrated Products  
Printed USA  
is a registered trademark of Maxim Integrated Products.  
配单直通车
MAX5020ESA产品参数
型号:MAX5020ESA
是否无铅: 含铅
是否Rohs认证: 不符合
生命周期:Obsolete
IHS 制造商:MAXIM INTEGRATED PRODUCTS INC
零件包装代码:SOIC
包装说明:0.150 INCH, SOIC-8
针数:8
Reach Compliance Code:not_compliant
ECCN代码:EAR99
HTS代码:8542.31.00.01
Factory Lead Time:1 week
风险等级:5.16
模拟集成电路 - 其他类型:SWITCHING CONTROLLER
控制模式:CURRENT-MODE
控制技术:PULSE WIDTH MODULATION
最大输入电压:12 V
最小输入电压:7.5 V
标称输入电压:9.8 V
JESD-30 代码:R-PDSO-G8
JESD-609代码:e0
长度:4.9 mm
湿度敏感等级:1
功能数量:1
端子数量:8
最高工作温度:85 °C
最低工作温度:-40 °C
最大输出电流:1 A
封装主体材料:PLASTIC/EPOXY
封装代码:SOP
封装形状:RECTANGULAR
封装形式:SMALL OUTLINE
峰值回流温度(摄氏度):245
认证状态:Not Qualified
座面最大高度:1.75 mm
表面贴装:YES
切换器配置:SINGLE
最大切换频率:302 kHz
技术:BICMOS
温度等级:INDUSTRIAL
端子面层:TIN LEAD
端子形式:GULL WING
端子节距:1.27 mm
端子位置:DUAL
处于峰值回流温度下的最长时间:NOT SPECIFIED
宽度:3.9 mm
Base Number Matches:1
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