Document
AAT4618
Current Limited Load Switch General Description
The AAT4618 SmartSwitch™ is a member of AnalogicTech's Application Specific Power MOSFET™ (ASPM™) product family. It is a Current Limited P-channel MOSFET power switch designed for high-side load-switching applications operating with inputs ranging from 2.4V to 5.5V which makes it ideal for 2.5V, 3V and 5V systems. An integrated current-limiting circuit protects the input supply from large currents which potentially cause the supply to fall out of regulation. In addition, the AAT4618 thermal overload protection limits power dissipation and junction temperatures associated with prolonged periods of operation in current limit. Due to its low RDS(ON), the AAT4618 can be used to control loads that require up to 500mA even while operating at high ambient temperatures. The ultra fast current-limit response to a sudden short circuit is a mere 400ns which reduces the requirements of local supply bypassing. An open drain FAULT flag signals an over current or over temperature condition after a 4ms timeout. Quiescent current is a low 10µA and in shutdown mode, the supply current decreases to less than 1µA. The AAT4618 is available in a 5 pin SOT-23, and an 8 pin SC70JW specified over a -40 to 85°C temperature range. The AAT4600 Series is a family of adjustable and fixed SmartSwitch™ products with a range of current handling capabilities. Available are single versions with adjustable current limit (AAT4610, AAT4601) as well as fixed current limit (AAT4625), and dual versions with fixed current limit (AAT4626, AAT4670).
Features
• • • •
SmartSwitch™
• • • • • • • •
2.4V to 5.5V Input voltage range 500mA min current limit trip threshold Fast transient response: • 400ns response to short circuit Low quiescent current • 10µA typical • < 1µA with Switch off 125mΩ typical R DS(ON) FAULT flag with 4ms blanking Undervoltage Lockout Thermal shutdown Temp range -40 to 85°C 4kV ESD Rating 5 pin SOT23 package 8 pin SC70JW package
Preliminary Information
Applications
• • • • • Peripheral ports USB Ports Notebook computers Personal communication devices Hot swap supplies
Typical Application
INPUT IN OUT OUTPUT
AAT4618
100k FAULT CIN 1µF ON (ON) ON (ON) GND COUT 0.47µF FAULT
GND
GND
4618.2002.2.0.9
1
AAT4618
Current Limited Load Switch Pin Descriptions
Pin #
SOT23-5 SC70JW-8
Symbol
OUT GND FAULT ON (ON) IN
Function
P-channel MOSFET drain Ground connection Open-drain FAULT output Enable Input: 4618 active low, 4618-1 active high P-channel MOSFET source
1 2 3 4 5
5 6, 7, 8 1 2 3, 4
Pin Configuration
SOT23-5 SC70JW-8
OUT GND FAULT
1 2 3
5
IN ON (ON)
4
FAULT ON (ON) IN IN
1 2
8 7
3 4
6 5
GND GND GND OUT
1 2
2
4618.2002.2.0.9
AAT4618
Current Limited Load Switch Absolute Maximum Ratings
Symbol
VIN, FAULT VON VOUT IOUT TJ VESD TLEAD
(TA=25°C unless otherwise noted) Value
-0.3 to 6 -0.3 to VIN+1 -0.3 to VIN+0.3 Internally Limited -40 to 150 4000 300
Description
IN, FAULT to GND ON (ON) to GN.