Usb Current-limited Switches With Fault Blanking Integrated Products

The MAX1693 MAX1694 are current-limited, 60m switches with built-in fault blanking. Their accurate pre- set current limit of 0.7A to 1.0A makes them ideally suit- ed for USB applications. Their low quiescent supply current (14A) and shutdown current (1A) conserve battery power in portable applications. The MAX1693 MAX1694 operate with inputs from +2.7V to +5.5V, making them ideal for both +3V and +5V systems. A fault signal notifies the Microprocessor that the inter- nal current limit has been reached. A 10ms fault-blank- ing feature allows momentary faults (such as those caused when hot-swapping into a capacitive load) to be ignored, thus preventing false alarms to the host system. This fault blanking also prevents a fault signal from being issued when the device is powering up. In the MAX1693 an output overcurrent condition caus- es the Switch to current limit at 0.7A to 1.0A and FAULT to go low after the 10ms blanking period. When the overcurrent condition is removed, FAULT returns to its high-impedance state. In the MAX1694 any overcur- rent longer than 10ms will latch the Switch open and set FAULT low. The latch is cleared by cycling the ON input or by powering up the device again. This feature saves power by preventing the device from thermally cycling on and off in case of a persistent short-circuit condition. The MAX1693 MAX1694 have several safety features to ensure that the USB port is protected. Built-in thermal- overload protection limits power dissipation and junc- tion temperatures. Both devices have accurate internal current-limiting circuitry to protect the input supply against overload. They are available in space-saving 10-pin MAX packages. By Maxim Integrated Products