The TPS20xxB power-distribution switches are intended forapplications where heavy capacitive loads and short circuits are likely to be encountered. Thesedevices incorporates 70-mΩ N-channel MOSFET power switches for power-distribution systems thatrequire multiple power switches in a single package. Each switch is controlled by a logic enableinput. Gate drive is provided by an internal charge pump designed to control the power-switch risetimes and fall times to minimize current surges during switching. The charge pump requires noexternal components and allows operation from supplies as low as 2.7 V.
When the output load exceeds the current-limit threshold or a short is present, thedevice limits the output current to a safe level by switching into a constant-current mode, pullingthe overcurrent (OCx) logic output low. When continuous heavy overloads andshort circuits increase the power dissipation in the switch, causing the junction temperature torise, a thermal protection circuit shuts off the switch to prevent damage. Recovery from a thermalshutdown is automatic once the device has cooled sufficiently. Internal circuitry ensures that theswitch remains off until valid input voltage is present. This power-distribution switch is designedto set current limit at 1 A (typical).