The MAX1940EEE triple current-limited switch with auto-reset supplies a guaranteed 500mA load per channel in accordance with USB specifications. The MAX1940EEE operates from a 4V to 5.5V input supply and consumes only 60μA of quiescent current when operating and only 3μA in standby. Selectable active-high/active-low control logic and independent shutdown controls for each channel provide additional flexibility. An autoreset feature latches the switch off in the event of a short circuit, saving system power. The switch reactivates upon removal of the shorted condition. The MAX1940EEE provides several safety features to protect the USB port. Built-in thermal-overload protection turns off the switch when the die temperature exceeds +160°C. Accurate internal current-limiting circuitry protects the input supply against both overload and short-circuit conditions. Independent open-drain fault signals (active-low FAULTA, active-low FAULTB, and active-low FAULTC) notify the microprocessor when a thermal-overload, current-limit, undervoltage lockout (UVLO), or short-circuit fault occurs. A 20ms fault-blanking feature enables the circuit to ignore momentary faults, such as those caused when hot-swapping a capacitive load, preventing false alarms to the host system. The fault-blanking feature also prevents fault signals from being issued when the device powers up the load. The MAX1940EEE is available in a space-saving 16-pin QSOP package and operates over the extended (-40°C to +85°C) temperature range.
Feature
- Triple USB Switch in Tiny 16-Pin QSOP Package
- Autoreset Feature Saves System Power
- Guaranteed 500mA Load Current per Channel
- Built-In 20ms Fault-Blanking Circuitry
- Active-High/Active-Low Control Logic
- Fully Compliant to USB Specifications
- 4V to 5.5V Input Voltage Range
- Independent Shutdown Control
- Independent Fault Indicator Outputs
- Thermal-Overload Protection
- 3μA Standby Current
Applications
- Computers: Desktop, Workstation, Server
- Docking Stations
- Notebook Computers
- PDAs and Palmtop Computers
- USB Hubs
- USB Ports