MIC2580A-1.0YTS

MIC2580A Micrel, Inc. MIC2580A Hot-Swap PCI Power Controller General Description Features The MIC2580A is a hot-swap controller that provides for safe PCI hot-plug and CompactPCI hot-swap support and orderly insertion and removal of PCI based adapter cards +12V, +5V, +3.3V, and 12V power supply control from a PCI hot-plug compliant system backplane or Circuit breaker function to protect system CompactPCI system. Programmable slew rate control for all supplies Foldback current-limiting The MIC2580A incorporates a circuit breaker function that +5V and +3.3V programmable current-limit thresholds protects all four supplies (+12V, +5V, +3.3V, and 12V) upon Undervoltage and overcurrent diagnostic outputs an overcurrent fault condition. Current foldback limiting pre- Deglitch filters on diagnostic fault outputs vents large transient currents caused by plugging adapter Integrated +12V and 12V MOSFET switches cards into live backplanes, such as in a CompactPCI system. Integrated high-side drivers for 3.3V and 5V external A programmable slew-rate control limits high inrush currents switches to all loads that occur when power is applied to large capaci- Precharge supply for CompatPCI I/O termination tive loads. Applications Voltage supervisory functions for all four power supplies are provided by power good (/PWRGD) and overcurrent fault PCI hot-plug systems (/FAULT) diagnostic outputs. Power good and overcurrent CompactPCI hot-swap systems fault include deglitch filters to prevent nuisance tripping. Power good is active when all four supplies are within tolerance. Fault (/FAULT) goes active upon overcurrent or overtemperature conditions. The on-off control input (/ON) is used to cycle power to the adapter card. Typical Application 10m IRF7413 1F 10m IRF7413 MIC2580A +12V +12V/1A +12V 12VIN 12VOUT +5V +5V/8A 5VSENSE +3.3V +3.3V/8A 5VGATE GND GND +5V 5VIN 5VOUT 12V 12V/1A 3VSENSE 1F 3VGATE +3.3V V IO 3VIN 3VOUT VIO 1F VPCHG V = +1V 20% V PCH 1.2k /POR IO (PRECHARGE SUPPLY) /PCI RST /PCIRST CRST /PCIRST /BD SEL /ON Overcurrent /ON /LPCIRST Fault CSLEW /FAULT /EPWRGD CSTART /HEALTHY /PGD /PWRGD GND 12V M12VIN M12VOUT 1F /LPCIRST /ENUM D0 D0 PCI D1 D1 Controller D2 D2 Dn Dn CompactPCI Adapter with Early Power CompactPCI is a trademark of the PCI Industrial Computer Manufacturers Group. Micrel, Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 MIC2580A Micrel, Inc. Ordering Information Part Number Precharge Temperature Standard Pb-Free Voltage Range Package MIC2580A-1.0BTS MIC2580A-1.0YTS 1V 40C to +85C 24-lead TSSOP MIC2580A-1.6BTS MIC2580A-1.6YTS 1.6V 40C to +85C 24-lead TSSOP Pin Configuration 12VOUT 1 24 12VIN 3VGATE 2 23 5VGATE 3VOUT 3 22 5VOUT 3VSENSE 4 21 5VSENSE 3VIN 5 20 5VIN /PCIRST 6 19 /FAULT /LPCIRST 7 18 CSTART /EPWRGD 8 17 CSLEW /PWRGD 9 16 /POR VPCHG 10 15 CRST GND 11 14 /ON M12VIN 12 13 M12VOUT 24-lead TSSOP (TS) Pin Description Pin Number Pin Name Pin Function 1 12VOUT +12V Switched Supply (Output): Load carrying output. 2 3VGATE 3.3V Gate Drive (Output): Drives gate of external N-channel MOSFET +3V switch. Adding capacitance will slow the slew rate of the external MOSFET switch turn-on. (The external MOSFETs gate is charged by an internal current source.) 3 3VOUT +3.3V Output Voltage Sense (Input): Connect to source of external N-channel MOSFET (+3V switched output) to monitor for output undervolt- age conditions. 4 3VSENSE +3.3V Current Sense (Input): Measures voltage drop across an external sense resistor with respect to 3VIN for overcurrent detection through the +3.3V switch. 5 3VIN 3V Supply (Input): +3.3V-supply input for current monitoring (reference input for 3VSENSE). Not a load-current carrying input. 6 /PCIRST PCI-Bus Reset (Input): Input from PCI bus that resets the internal logic. MIC2580A 2 February 2005