The TPS2306 Hot Swap Power Manager (HSPM) IC provides hot-swap control, fault handling and power supply sequencing of two positive voltage supplies. The TPS2306 operates over a wide supply range allowing single part inventory for a variety of output voltages.
●During the transient period of a live insertion or hot-swap event, the TPS2306 actively limits the inrush current to the plug-in module. An on-chip linear current amplifier (LCA) provides closed-loop control of the current sourced to the load circuitry on the module. Subsequently, during normal steady-state loading conditions and in conjunction with an internal high-voltage charge pump, the LCA provides direct gate drive to fully enhance the external NMOS pass devices. In addition, the < 4-mV input offset voltage of the LCA allows for the use of low-value sense resistors. Together, these features minimize the insertion loss across the hot-swap interface.
●Control inputs allow the designer to program the maximum current level and the inrush current profile (slew rate) during start-up. Direct programming of the fault time-out also allows the user to establish how long the HSPM can operate in the current control mode prior to turning off the pass elements. The high degree of user programmability allows the TPS2306 to be configured for the specific load and bulk capacitance charging requirements of the target system.
●A second level of power bus protection is provided in the form of fast overcurrent comparators monitoring the load current levels of the two channels. Should a short-circuit event"s edge rate ever exceed the slew rate of the LCA, the overcurrent comparator immediately latches off the external NMOS devices, overriding the timeout period. The overcurrent threshold is also user-programmable.
●Supply sequencing control is provided via four comparator inputs to independently control the ramp-up and ramp-down of each supply output (see Figure 1). The TPS2306 also provides a TTL and CMOS compatible enable input for external control of the supply outputs, and a low-power sleep mode. Also, the open-drain FAULT output provides single-line fault reporting to the system host for the two monitored supplies.
● Wide Input Operating Range (2.75 V to 13.6 V)
● Controls Ramp-Up Sequence and Slope, and Ramp-Down Sequence
● Controls Inrush Current
● Precise Linear Current Amplifier for High Efficiency and Low Voltage Drop
● Programmable Overcurrent Threshold
● Programmable Soft-Start Capability and Fault Timer
● Internal Charge Pump Drives Low-Cost External NMOS Devices
● Cascadable for Three or More Supplies
● Fault Indicator Output
● Direct-drive of Bus Switch
● Shutdown Control with Low-Current Sleep Mode (40 uA)
● Input Undervoltage Lockout
● 16-pin SOIC package
●QuickSwitch® is a registered trademark of Integrated Device Technology, Inc.
●Widebus is a trademark of Texas Instruments Incorporated.
