The MAX4826–MAX4831 family of switches has internal current limiting to prevent host devices from being damaged due to faulty load conditions. These analog switches have a low 0.7Ω on-resistance and operate from a +2.3V to +5.5V input voltage range. These devices are available with guaranteed 50mA and 100mA current limits, making them ideal for load-switching applications. In addition to the current-limit fault flag (active-low FFLG), an open-drain no-load flag indicator (active-low NOLD) notifies the system when the current through the switch is less than 10mA (MAX4826–MAX4829), or 5mA (MAX4830/MAX4831).
When the switch is on and a load is connected to the port, a guaranteed blanking time of 14ms ensures that the transient voltages settle down. If, after this blanking time, the load current is greater than the current limit, the MAX4826/MAX4828/MAX4830 enter a latchoff state where the switch is turned off, and FFLG is issued to the microprocessor. The switch can be turned on again by cycling the power or ON.
The MAX4827/MAX4829/MAX4831 have an autoretry feature where the switch turns off after the blanking time, and then continuously checks to see if the overload condition is present. The current-limit fault flag (active-low FFLG) is issued and remains low until after the fault condition is removed. The switch remains on after the overload condition disappears.
The MAX4826–MAX4831 operate over the extended -40°C to +85°C temperature range, and are available in tiny space-saving, 1mm x 1.5mm, 6-pin µDFN package.
Applications
- Cell Phones
- Digital Still Cameras
- Global Positioning Systems (GPS)
- MP3 Players
- PDAs and Palmtop Devices
