Features
12-V - 12-V, 3.3-V, 5-V main power switch and auxiliary 3.3-V power switch
12 V, 12 V and auxiliary 3.3-V power FETs
Hot-swap protection and control of all supplies Overcurrent protection of all power supplies One of the main 12 V, 3.3 V, 5 V and auxiliary 3.3-V power supplies under voltage monitoring from any load fault in any other slot Fault Latch Thermal Shutdown Open Drain LED Driver Slot Status Readout Attention Request and Electrical Interlock Mechanical Switch Input Serial Interface Power Control, Power Status, Time Slot Control and Slot Status Compatible with 33 MHz, 66 MHz, and 133- MHz bus speed compliant with PCI and PCI-X hot-plug specifications One TPS2340A supports two slots

describe
The TPS2340A contains main power supply control, auxiliary power supply power control, power field effect transistors (FETs) for 12 V, 12 V and auxiliary 3.3 V power supplies, and a control slot for communication and serial interface. Each TPS2340A contains controls and switches that supply two slots. Begin with all major power supply control circuit supplies turned off, and hold until the power supply shuts down the TPS2340A is active with all active supplies. When power is required via the serial interface, the control circuit employs gates of constant current power FETs, allowing each FET to ramp with a linear relationship to the voltage applied. The desired ramp rate for each power supply can be programmed to supply the gate capacitance of the power FET. The power control circuit monitors the load current and latches off the slot if the load current exceeds the set maximum value. In addition, 12-V, 5-V, 3.3-V FETs are fully enhanced, and the load voltage is monitored. If the load voltage drops after the specifications of these FETs are fully boosted, the slot latches off. This provides another level of protection from load failures. The auxiliary power control circuit switches, ramps, and monitors each 3.3 V auxiliary power slot. The auxiliary control circuit also controls the data switch connection slot to be interrupted (power management event [PME] main output) to interrupt the PME bus connection after the 3.3 V auxiliary supply. The circuit board of the motorized equipment is disconnected when it shuts down or malfunctions. Each TPS2340A contains 12 V power FETs for 500 mA, -12 V for 100 mA, and a 3.3 V secondary for 375 mA per slot. These power FETs are short circuit protected, slew rate controlled, and over temperature protected. The serial interface uses a synchronous serial protocol with a slot controller. Interfaces with slots, status LEDs, and dedicated lines with individual mechanical switches. The interface powers from 3.3 V, but the input is 5 V tolerant. The status LED driver drives a 24mA LED through an integrated open-drain MOSFET. Mechanical switch inputs have internal pull-ups and hysteresis buffers. The serial interface controls slot power, bus connections, and LED outputs, and monitors the board's ability to power down, and toggle input states.