FPF2125 Datasheet, PDF (1/13 Pages) Fairchild Semiconductor – IntelliMAX Advanced Load Management Products

August 2005
FPF2123-FPF2125
IntelliMAX™ Advanced Load Management Products
Features
„ 1.8 to 5.5V Input Voltage Range
„ Controlled Turn-On
„ 0.15-1.5A Adjustable Current Limit
„ Undervoltage Lockout
„ Thermal Shutdown
„ <2uA Shutdown Current
„ Auto Restart
„ Fast Current limit Response Time
„ 3us to Moderate Over Currents
„ 20ns to Hard Shorts
„ Fault Blanking
„ Reverse Current Blocking
Applications
„ PDAs
„ Cell Phones
„ GPS Devices
„ MP3 Players
„ Digital Cameras
„ Peripheral Ports
„ Hot Swap Supplies
Typical Application Circuit
General Description
The FPF2123, FPF2124, and FPF2125 are a series of load
switches which provides full protection to systems and loads
which may encounter large current conditions. These devices
contain a 0.125Ω current-limited P-channel MOSFET which can
operate over an input voltage range of 1.8-5.5V. The current
limit is settable using an external resistor. Internally, current is
prevented from flowing when the MOSFET is off and the output
voltage is higher than the input voltage. Switch control is by a
logic input (ON) capable of interfacing directly with low voltage
control signals. Each part contains thermal shutdown protection
which shuts off the switch to prevent damage to the part when a
continuous over-current condition causes excessive heating.
When the switch current reaches the current limit, the parts
operate in a constant-current mode to prohibit excessive
currents from causing damage. For the FPF2123 and FPF2124
if the constant current condition still persists after 10ms, these
parts will shut off the switch. The FPF2123 has an auto-restart
feature which will turn the switch on again after 160ms if the ON
pin is still active. The FPF2124 does not have this auto-restart
feature so the switch will remain off after a current limit fault until
the ON pin is cycled. The FPF2125 will not turn off after a
current limit fault, but will rather remain in the constant current
mode indefinitely. The minimum current limit is 150mA.
These parts are available in a space-saving 5 pin SOT23
package
OFF ON
V_IN
V_OUT
FPF2123 - FPF2125
ON
ISET
GND
TO LOAD
©2005 Fairchild Semiconductor Corporation
1
FPF2123-FPF2125 Rev. C
www.fairchildsemi.com