- 您现在的位置：买卖IC网 > PDF目录1841 > MAX1980ETP+ (Maxim Integrated Products)IC REG CTRLR BUCK PWM 20-TQFN PDF资料下载
参数资料
| 型号： | MAX1980ETP+ |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 21/33页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM 20-TQFN |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 60 |
| 系列： | Quick-PWM™ |
| PWM 型： | 控制器 |
| 输出数： | 1 |
| 频率 - 最大： | 550kHz |
| 占空比： | 50% |
| 电源电压： | 4.5 V ~ 5.5 V |
| 降压： | 是 |
| 升压： | 无 |
| 回扫： | 无 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 无 |
| Cuk： | 无 |
| 隔离： | 无 |
| 工作温度： | 0°C ~ 85°C |
| 封装/外壳： | 20-WQFN 裸露焊盘 |
| 包装： | 管件 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页当前第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页
Quick-PWM Slave Controller with
Driver Disable for Multiphase DC-DC Converter
R C = ?
- 1 ? x 30 . 1 k ? ≈ 113 k ?
1 . 3 V x ( )
? I INDUCTOR =
= 6 . 4 A
R LIMIT ≤ ( 53 . 6 k ? // 100 k ? ) x 3 m ? ≈ 35 k ?
Current Limit Design Example
For the typical application circuit shown in Figure 1 V IN
= 12V, V OUT = 1.3V, f SW = 300kHz, η = 2, I LOAD(MAX)
= 50A, L = 0.6μH, R DS(ON)(MAX) = 6m ? , R DS(ON)(MIN )
= 3m ? .
1) Determine the peak-to-peak inductor current and
the valley current limit:
12 V - 1 . 3 V
12 V x 300 kHz x 0 . 6 μ H
? 2 V ?
? 10 x 42 mV ?
4) Determine R LIMIT (Figure 5) from the above equation:
6 m ? - 3 m ?
5) Finally, verify that that the total bias currents do not
exceed the 50μA maximum load of the master ’ s ref-
I LIMIT ( VALLEY ) = ?
? - ?
x 6 . 4 A ? = 21 . 8 A
? 54 k ? + ( 100 k ? // 34 . 8 k ? ) ?
? 50 A ? ? 1
? 2 ? ? 2
?
?
erence:
? 2 V ?
I BIAS ( TOTAL ) = ? ?+
? = 36 μ A
?
Unadjusted ? I LIMIT = V ITHM ( HIGH ) ? ?
R B = ?
? = 65 k ? to 130 k ?
? to ?
2) Determine the master ’ s current-limit threshold from
the valley current limit and low-side MOSFETs ’ max-
imum on-resistance over temperature:
V ITH(MASTER) ≥ 21.8A ? 6m ? = 130mV
Now select the resistive-divider values (R A and R B
in Figure 5) to set the appropriate voltage at the
master ’ s ILIM input:
? 10 x 130 mV ? ? 10 x 130 mV ?
? 20 μ A ? ? 10 μ A ?
Selecting R B = 100k ? ±1% provides the following
value for R A :
? 2 V ?
? 30 . 1 k ? + 113 k ? ?
When unadjusted, the on-resistance variation of the
low-side MOSFETs results in a maximum current-limit
variation ( ? I LIMIT ) determined by the following equation:
? A RDS ? 1 ?
? R DS ( ON )( MAX ) ?
where A RDS = R DS(ON)(MAX) /R DS(ON)(MIN) . Using the
MAX1980 to adjust the master ’ s current-limit threshold
results in a maximum current-limit variation less than
the peak-to-peak inductor current:
R A = ?
? 1 ? x 100 k ? ≈ 54 k ?
? 2 V
? 10 x 130 mV
?
?
Adjusted ? I LIMIT ≤ ? I INDUCTOR
As shown in Figure 6, the resulting current-limit varia-
tion of the master is dramatically reduced. For the
3) Determine the slave ’ s current-limit threshold:
above example, this control scheme reduces the cur-
rent-limit variation from 21.7A (unadjusted) to less than
V ITHS ≥ 1 . 5 m ? x ?
+ 6 . 4 A ? ≈ 42 mV
? 130mV
? 6 m ?
?
?
6.4A (adjusted).
Output Capacitor Selection
The output filter capacitor must have low enough ESR to
R D = ?
? = 21 k ? to 42 k ?
? to ?
Select the resistive-divider values (R C and R D in
Figure 5) to set the appropriate voltage at the
slave ’ s ILIM input:
? 10 x 42 mV ? ? 10 x 42 mV ?
? 20 μ A ? ? 10 μ A ?
Selecting R D = 30.1k ? ±1% provides the following
meet output ripple and load-transient requirements, yet
have high enough ESR to satisfy stability requirements.
In CPU V CORE converters and other applications where
the output is subject to large load transients, the output
capacitor selection typically depends on how much
ESR is needed to prevent the output from dipping too
low under a load transient. Ignoring the sag due to
finite capacitance:
value for R A :
R ESR ≤
V STEP
? I LOAD ( MAX )
______________________________________________________________________________________
21
相关PDF资料 |
PDF描述 |
|---|---|
| MAX1983EUT+T | IC REG LDO ADJ .3A SOT23-6 |
| MAX1992ETG+T | IC REG CTRLR BUCK PWM CM 24-TQFN |
| MAX1997ETJ+T | IC PWR SUPPLY TFT LCD 32TQFN |
| MAX256ASA+T | IC DRVR H-BRIDGE 8-SOIC |
| MAX3273ETG+T | IC LASR DRVR 2.7GBPS 3.6V 24TQFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX1980ETP+ | 功能描述:DC/DC 开关控制器 PWM Slave Controller w/Driver Disable RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1980ETP+T | 功能描述:DC/DC 开关控制器 PWM Slave Controller w/Driver Disable RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1980ETP+TG075 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX1980ETP-T | 功能描述:DC/DC 开关控制器 RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1980ETP-TG075 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
发布紧急采购，3分钟左右您将得到回复。