参数资料
型号: AP2142AFGEG-7
厂商: Diodes Inc
文件页数: 11/16页
文件大小: 0K
描述: IC PWR SW USB 2CH 0.5A 8-DFN
产品变化通告: Copper Bond Wire Change 13/Jan/2012
标准包装: 1
类型: USB 开关
输出数: 2
Rds(开): 105 毫欧
内部开关:
电流限制: 700mA
输入电压: 2.7 V ~ 5.5 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 8-DFN 裸露焊盘
供应商设备封装: 8-DFN3030E(3x3)
包装: 标准包装
其它名称: AP2142AFGEG-7DIDKR
P D = R DS(ON) × I
AP2142A/ AP2152A
Application Information
Power Supply Considerations
A 0.1 μ F to 1 μ F X7R or X5R ceramic bypass capacitor between IN and GND, close to the device, is recommended. Placing a high-value electrolytic
capacitor on the input and output pin(s) is recommended when the output load is heavy. This precaution reduces power-supply transients that may
cause ringing on the input. Additionally, bypassing the output with a 1 μ F ceramic capacitor improves the immunity of the device to short-circuit
transients.
Over-Current and Short Circuit Protection
An internal sensing FET is employed to check for over-current conditions. Unlike current-sense resistors, sense FETs do not increase the series
resistance of the current path. When an overcurrent condition is detected, the device maintains a constant output current and reduces the output
voltage accordingly. Complete shutdown occurs only if the fault stays long enough to activate thermal limiting.
Three possible overload conditions can occur. In the first condition, the output has been shorted to GND before the device is enabled or before V IN
has been applied. The AP2142A/AP2152A senses the short circuit and immediately clamps output current to a certain safe level namely I LIMIT .
In the second condition, an output short or an overload occurs while the device is enabled. At the instance the overload occurs, higher inrush
current may flow for a very short period of time before the current limit function can react. The input capacitor(s) rapidly discharge through the
device, activating current limit circuitry. Protection is achieved by momentarily opening the P-MOS high-side power switch and then gradually
turning it on. After the current limit function has tripped (reached the over-current trip threshold), the device switches into current limiting mode and
the current is clamped at I LIMIT . The threshold for activating current limiting is 0.7A typical per channel.
In the third condition, the load has been gradually increased beyond the recommended operating current. The current is permitted to rise until the
current-limit threshold (I TRIG ) is reached or until the thermal limit of the device is exceeded. The AP2142A/AP2152A is capable of delivering current
up to the current-limit threshold without damaging the device. Once the threshold has been reached, the device switches into its current limiting
mode and is set at I LIMIT .
FLG Response
When an over-current or over-temperature shutdown condition is encountered, the FLG open-drain output goes active low after a nominal 7-ms
deglitch timeout. The FLG output remains low until both over-current and over-temperature conditions are removed. Connecting a heavy capacitive
load to the output of the device can cause a momentary over-current condition, which does not trigger the FLG due to the 7-ms deglitch timeout.
The AP2142A/AP2152A is designed to eliminate false over-current reporting without the need of external components to remove unwanted pulses.
Power Dissipation and Junction Temperature
The low on-resistance of the internal MOSFET allows the small surface-mount packages to pass large current. Using the maximum operating
ambient temperature (T A ) and R DS(ON) , the power dissipation can be calculated by:
2
Finally, calculate the junction temperature:
T J = P D x R ? JA + T A
Where:
T A = Ambient temperature ? C
R ? JA = Thermal resistance
P D = Total power dissipation
Thermal Protection
Thermal protection prevents the IC from damage when heavy-overload or short-circuit faults are present for extended periods of time. The
AP2142A/AP2152A implements a thermal sensing to monitor the operating junction temperature of the power distribution switch. Once the die
temperature rises to approximately 140°C due to excessive power dissipation in an over-current or short-circuit condition the internal thermal sense
circuitry turns the power switch off, thus preventing the power switch from damage. Hysteresis is built into the thermal sense circuit allowing the
device to cool down approximately 25°C before the switch turns back on. The switch continues to cycle in this manner until the load fault or input
power is removed. The FLG open-drain output is asserted when an over-temperature shutdown or over-current occurs with 7-ms deglitch.
AP2142A/ AP2152A
Document number: DS32191 Rev. 3 - 2
11 of 16
March 2013
? Diodes Incorporated
相关PDF资料
PDF描述
RMC05DREF-S13 CONN EDGECARD 10POS .100 EXTEND
101-1157 KIT DEVELOPMENT USA RCM4100
SC53LC-100 INDUCTOR SMD 10UH 1.33A 100KHZ
GEC12DRTS-S734 CONN EDGECARD 24POS DIP .100 SLD
RBC19DREH CONN EDGECARD 38POS .100 EYELET
相关代理商/技术参数
参数描述
AP2142AMPG-13 功能描述:电源开关 IC - USB DUAL SWITCH 125mOhms 0.5A 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
AP2142ASG-13 功能描述:电源开关 IC - USB DUAL SWITCH 130mOhms 0.5A 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
AP2142MPG-13 功能描述:电源开关 IC - USB 0.5A 2.7V-5.5V 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
AP2142SG-13 功能描述:电源开关 IC - USB 0.5A 2.7V-5.5V 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
AP2145 制造商:DIODES 制造商全称:Diodes Incorporated 功能描述:0.5A SINGLE CHANNEL CURRENT-LIMITED POWER SWITCH