参数资料
型号: MAX1940EEE+
厂商: Maxim Integrated Products
文件页数: 11/13页
文件大小: 0K
描述: IC SW USB TRPL 16-QSOP
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 100
应用: USB,外设
电流 - 电源: 60µA
电源电压: 4 V ~ 5.5 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 16-SSOP(0.154",3.90mm 宽)
供应商设备封装: 16-QSOP
包装: 管件
Triple USB Switch with Autoreset and
Fault Blanking
An active switch dissipates little power with minimal
change in package temperature. Calculate the power
dissipation for this condition as follows:
INPUT
4V TO 5.5V
IN1
IN2
MAX1940
FAULTA
FAULTB
100k ?
100k ?
100k ?
P = (I OUT_ ) 2 x R ON
At the normal operating current (I OUT_ = 0.5A) and the
maximum on-resistance of the switch (135m ? ), the
power dissipation is:
P = (0.5A) 2 x 0.135 ? = 34mW per switch.
O.1 μ F
IN3
IN4
FAULTC
The worst-case power dissipation occurs when the output
current is just below the current-limit threshold (1.2A max)
with an output voltage greater than 1V. In this case, the
IN5
OUTA
USB
PORT A
power dissipated in each switch is the voltage drop
across the switch multiplied by the current limit:
ON
OFF
ONA
ONB
OUTB
1 μ F*
USB
PORT B
1 μ F*
P = I LIM x (V IN - V OUT )
For a 5V input and 1V output, the maximum power dis-
sipation per switch is:
P = 1.2A x (5V - 1V) = 4.8W
ONC
Because the package power dissipation is 667mW, the
SEL
GND
OUTC
USB
PORT C
1 μ F*
MAX1940 die temperature exceeds the +160°C thermal
shutdown threshold, and the switch output shuts down
until the junction temperature cools by +15°C. The duty
cycle and period are strong functions of the ambient
temperature and the PC board layout (see the Thermal
*USB APPLICATIONS MAY REQUIRE
ADDITIONAL BULK CAPACITANCE
Figure 2. Typical Application Circuit
power bus with short traces. Wide power bus planes at
IN_ and OUT provide superior heat dissipation as well.
Shutdown section).
If the output current exceeds the current-limit threshold,
or the output voltage is pulled below the short-circuit
detect threshold, the MAX1940 enters a fault state after
20ms, at which point autoreset mode is enabled and
25mA is sourced by the output. For a 5V input, OUT_
short-circuited to GND, and autoreset mode active, the
power dissipation is as follows:
P = 0.025A x 5V = 0.125W
______________________________________________________________________________________
11
相关PDF资料
PDF描述
MAX1945REUI+T IC REG BUCK 6A 28TSSOP
MAX1946ETA+T IC USB SW SGL AUTORESET 8TDFN
MAX1947ETA25+T IC REG BST SYNC 2.5V 0.25A 8TDFN
MAX1951AESA+T IC REG BUCK SYNC ADJ 2A 8SOIC
MAX1951ESA+W IC REG BUCK SYNC ADJ 2A 8SOIC
相关代理商/技术参数
参数描述
MAX1940EEE+ 功能描述:电源开关 IC - USB Triple USB Switch w/Autoreset RoHS:否 制造商:Micrel 电源电压-最小:2.7 V 电源电压-最大:5.5 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:SOIC-8 封装:Tube
MAX1940EEE+T 功能描述:电源开关 IC - USB Triple USB Switch w/Autoreset RoHS:否 制造商:Micrel 电源电压-最小:2.7 V 电源电压-最大:5.5 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:SOIC-8 封装:Tube
MAX1940EEE-T 功能描述:电源开关 IC - USB Triple USB Switch w/Autoreset RoHS:否 制造商:Micrel 电源电压-最小:2.7 V 电源电压-最大:5.5 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:SOIC-8 封装:Tube
MAX1945EVKIT 制造商:Maxim Integrated Products 功能描述:1MHZ, 1% ACCURATE, 6A INTERNAL SWITCH STEP-DO - Bulk
MAX1945REUI 功能描述:直流/直流开关调节器 RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5