AAT4674 Datasheet, PDF (1/13 Pages) Advanced Analogic Technologies – Power Supply Selector Switch

General Description
The AAT4674/4674-1 are members of Analogic-
Tech’s Application Specific Power Management
SmartSwitch™ family. These devices are dual
input single output power supply selector switches
designed to operate from batteries, or any other
power supply with an input voltage up to 6V.
The AAT4674/4674-1 connects the supply voltage
on IN1 to OUT, or IN2 to OUT, through a very low
R_DS(ON) power MOSFET that minimizes voltage
drops and power dissipation. The enable (EN) and
select (SEL) pin voltages control the operational
state of the internal power MOSFET switches.
Once enabled, the SEL pin will switch between the
IN1 and IN2 inputs. If both input voltages are below
the UVLO, then the AAT4674 output floats. In the
case of the AAT4674-1, if one of the input voltages
is above the UVLO threshold then that input volt-
age that is above the UVLO threshold is passed
through to the output.
The two power switches are current limited and the
current limit thresholds can be programmed through
the resistors on IIN1 and IIN2 pins respectively.
The AAT4674/4674-1 are available in thermally
enhanced, space-saving Pb-free 12-pin TSOPJW
packages. The AAT4674/4674-1 are specified for
operation over the -40°C to +85°C temperature
range.
AAT4674
Power Supply Selector Switch
Features
SmartSwitch^™
• Input Voltage Supply Range: 2.5V to 6V
• High Level of Integration:
— Reverse Blocking Diode
— Current Sensing
— Programmable Current Limit
— Single Control Pin Switching
• Break-Before-Make Switch-Over
— Minimum Output Voltage Drop During
Change-Over
• Shutdown Current < 1µA
• Thermal Protection
• TSOPJW-12 Package
Applications
• Bluetooth™ Headsets
• Cell Phones
• Digital Still Cameras
• MP3 Players
• Personal Data Assistants (PDAs)
• Set Top Boxes
Typical Application
+5V
IN1
+3.3V
IN2
IN1/IN2 Select
SEL
Enable
EN
OUT
IIN1
IIN2
GND
System Load
R_IIN2
R_IIN1
4674.2007.09.1.0
1