MIC2012ZM Microchip

MIC2012 Micrel MIC2012/MIC2072 USB Power Controller General Description Features The MIC2012 is a dual channel USB power switch designed to Compliant to USB power distribution speci cations support the power distribution requirements for USB Wakeup UL Recognized Component from the ACPI S3 state. The MIC2012 will directly switch its Two completely independent switches two outputs between a 5V main supply and a 5V auxiliary Integrated switching matrix supports ACPI S0/S3 state supply normally provided in ATX style power supplies. transitions without external FET circuits Make-before-break switching ensures glitch-free The MIC2012 will adjust its current-limit threshold according transitions to the ACPI state it is in. In the normal active S0 state the cur- No back-feed of auxiliary supply onto main supply dur- rent-limit is set at 500mA minimum per channel satisfying the ing standby mode USB continuous output current speci cation. In the S3 state Bi-level current-limit preserves auxiliary supply voltage the current-limit can be reduced to only 100mA per channel regulation in standby mode to minimize the current that is supplied by the auxiliary supply Thermally isolated channels thereby ensuring that voltage regulation is maintained even Thermal shutdown protection during fault conditions. Fault status outputs with lter prevents false assertions The MIC2012 provides make-before-break switching to ensure during hot-plug events glitch-free transitions between the S3 and S0 states. Each Latched thermal shutdown options with auto-reset channel is also thermally isolated from the other so that a (MIC2072) fault in one channel does not effect the other. FAULT status Undervoltage lockout output signals are also provided indicating overcurrent and thermal shutdown conditions. Applications The MIC2072 option latches the output off upon detecting an overcurrent condition for more than 5ms minimum. The Desktop PCs output can be reset by either toggling the EN inputs of the Notebook PCs MIC2072-1, -2 or by removing the load. Latching the output Notebook Docking stations off provides a circuit breaker mode of operation which reduces LAN Servers power consumption during fault conditions. PC Motherboards Typical Application ATX Power Supply 5V MAIN V BUS 5V STANDBY Downstream D+ MIC2012P USB D Port 1 OUT1 MAIN GND 100F AUX OUT2 S3 Control S3 V FAULT1 BUS Downstream FAULT2 D+ USB GND D Port 2 100F GND 82801AA or Equivalent SLP S3 SLP S5 Overcurrent Port 1 OC0 Overcurrent Port 1 OC1 Figure 1. USB Wakeup with Control Input UL Recognized Component Micrel, Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 MIC2012 Micrel Ordering Information Part Number Circuit Breaker Temperature Enable Fault Output Range Range Package Standard Pb-Free (1) (1) MIC2012BM MIC2012YM n/a Open-Drain 0C to +70C 8-lead SOIC MIC2012CM MIC2012ZM n/a Open-Drain 0C to +70C 8-lead SOIC MIC2012PCM MIC2012PZM n/a Internal Pull-Up 0C to +70C 8-lead SOIC MIC2012-1PCQS MIC2012-1PZQS Active High Internal Pull-Up 0C to +70C 16-lead QSOP MIC2012-2PCQS MIC2012-2PZQS Active Low Internal Pull-Up 0C to +70C 16-lead QSOP MIC2072-1PCQS MIC2072-2PZQS Active High Internal Pull-Up 0C to +70C 16-lead QSOP MIC2072-2PCQS MIC2072-2PZQS Active Low Internal Pull-Up 0C to +70C 16-lead QSOP Note: 1. Contact factory for availablity Pin Con guration FAULT1 1 16 FAULT2 EN1 2 15 EN2 FAULT1 1 8 FAULT2 S3 3 14 OUT1 S3 2 7 OUT1 NC 4 13 OUT1 AUX 3 6 MAIN AUX 5 12 MAIN GND 4 5 OUT2 NC 6 11 MAIN 8-Pin SOIC (M) NC 7 10 OUT2 GND 8 9 OUT2 16-Pin QSOP (QS) MIC2012/2072 2 January 2005