FPF2109: Full Function Load Switch with Reverse Current Blocking

The FPF2108-FPF2110 is a series of load switches which provides full protection to systems and loads which may encounter large current conditions. This devices contain a 0.125W current-limited P-channel MOSFET which can operate over an input voltage range of 1.8-5.5V. Internally, reverse current blocking prevents current 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 part operates in a constant-current mode to prohibit excessive currents from causing damage. For the FPF2108, if the constant current condition still persists after 10ms, the part will shut off the switch and pull the fault signal pin (FLAGB) low. The switch will remain off until the ON pin is cycled. For the FPF2109 and FPF2110, a current limit condition will immediately pull the fault signal pin low and the part will remain in the constant-current mode until the switch current falls below the current limit. The minimum current limit is 200mA for the FPF2109 while that for the FPF2108 and FPF2110 is 400mA. These parts are available in a space-saving 5 pin SOT23 package

Features

• 1.8 to 5.5V Input Voltage Range
• Controlled Turn-On
• 200mA Current Limit Options
• Undervoltage Lockout
• Thermal Shutdown
• <2uA Shutdown Current
• Fast Current limit Response Time
• 3us to Moderate Over Currents
• 20ns to Hard Shorts
• Reverse Current Blocking
• Fault Blanking
• RoHS Compliant

Application Notes