TPS2340A Datasheet, PDF (1/27 Pages) Texas Instruments – DUAL-SLOT PCI HOT-PLUG POWER CONTROLLER

TPS2340A
SLUS528A – MARCH 2002 – REVISED AUGUST 2002
DUALĆSLOT PCI HOTĆPLUG
POWER CONTROLLER
FEATURES
D 12-V, –12-V, 3.3-V, 5-V Main Power Switching
and Auxiliary 3.3-V Power Switching
D 12-V, –12-V And Auxiliary 3.3-V Power FETs
D Hot-Swap Protection and Control of All
Supplies
D Overcurrent Protection for All Supplies
D Isolation of Any Load Fault in One Slot from
Any Other Slot
D Undervoltage Monitoring for the Main 12-V,
3.3-V, 5-V and Auxiliary 3.3-V Supplies
D Power Fault Latching
D Overtemperature Shutdown
D Slot Status Readout with Open-Drain LED
Drivers
D Mechanical Switch Inputs for Attention
Request and Electrical Interlock
D Serial Interface for Power Control, Power
Status, Slot Control and Slot Status
D Compatible With 33-MHz, 66-MHz, and
133-MHz Bus Speeds
D Compliant To PCI And PCI-X Hot Plug
Specifications
D One TPS2340A Supports Two Slots
DESCRIPTION
The TPS2340A contains main supply power
control, auxiliary supply power control, power
FETs for 12 V, –12 V and auxiliary 3.3 V supplies,
and a serial interface for communications with and
control of slots. Each TPS2340A contains supply
control and switching for two slots.
The main power control circuits start with all
supplies off and hold all supplies off until power to
the TPS2340A is valid on all positive supplies.
When power is requested via the serial interface,
the control circuit applies constant current to the
gates of the power FETs, allowing each FET to
ramp load voltage linearly. Each supply can be
programmed for a desired ramp rate by selecting
a gate capacitor for the power FET for that supply.
The power control circuits also monitor load
current and latch off that slot if the load current
exceeds a programmed maximum value. In
addition, once the 12-V, the 5-V, and the 3.3-V
FETs are fully enhanced, the load voltage is
monitored. If load voltage drops out of
specification after these FETs are fully enhanced,
the slot latches off. This provides another level of
protection from load fault.
The auxiliary power control circuit switches,
ramps, and monitors 3.3-V auxiliary power to each
slot. The auxiliary control circuit also controls data
switches that connect slot interrupts (power
management event [PME] outputs) to the main
interrupt PME bus after 3.3-V auxiliary supply is
connected. PME is disconnected when a board is
turned off or faulted.
Each TPS2340A contains power FETs for 12 V at
500 mA, –12 V at 100 mA, and auxiliary 3.3 V at
375 mA for each slot. These power FETs are
short-circuit protected, slew rate controlled, and
over-temperature protected.
The serial interface communicates with a slot
controller using a synchronous serial protocol.
The interface communicates with the slot, status
LEDs, and mechanical switches with individual,
dedicated lines. The interface operates from 3.3-V
power but inputs are 5-V tolerant. Status LED
drivers are capable of driving 24-mA LEDs via
integrated open-drain MOSFETs. Mechanical
switch inputs have internal pull-up and hysteresis
buffers. The serial interface controls slot power,
bus connection, and LED outputs, and monitors
board capability, power fault, and switch input
status.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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Copyright  2002, Texas Instruments Incorporated
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