MIC2536 Micrel MIC2536 Dual USB Power Distribution Switch Final Information General Description Features The MIC2536 is a cost-effective high-side power switch, with Compliant to USB specifications two independently controlled channels, optimized for bus- 2.7V to 5.5V operating range powered Universal Serial Bus (USB) applications. Few exter- 150mA minimum continuous load current per channel nal components are necessary to satisfy USB requirements. 400m typical on-resistance Fast-acting short circuit protection with Each switch channel of the MIC2536 will supply up to 100mA thermal shutdown as required for USB bus-powered downstream devices. Fault Integrated filter eliminates current is limited to typically 275mA by fast-acting current- false overcurrent flag assertions limit circuitry which minimizes voltage droop on the upstream Individual open-drain fault flag pins with transient filter port during fault conditions. A flag output with transient filter 3V/5V-compatible enable inputs indicates fault conditions to the local USB controller but will Active-high (-1) and active-low (-2) versions ignore short flag signals resulting from inrush current during Reverse-current blocking in off mode (no body diode) hot plug-in events. Soft-start circuit Soft start eliminates the momentary voltage droop on other 100 A maximum on-state supply current ports that may occur when the switch is enabled in bus- <1 A typical off-state supply current powered applications. Additional features include thermal 40C to 85C operation shutdown to prevent catastrophic switch failure from high- Applications current loads and 3.3V and 5V logic compatible enable inputs. USB keyboard bus-powered hubs The MIC2536 is available in active-high and active-low ver- USB bus-powered docking stations sions in 8-lead SOP and MSOP. Note Book PCs PDAs General purpose power distribution applications PC board hot swap Inrush current-limiting Typical Application Ferrite Beads 10k 4.50V to 5.25V V BUS 1.5k Upstream V 10k BUS D+ 100mA max. MIC5207-3.3 3.3V USB Controller MIC2536-2 USB .01F D V BUS Port 1 63F IN OUT VIN ON/OFF ENA OUTA GND D+ OVERCURRENT FLGA IN 1F 0.1F D GND OVERCURRENT FLGB GND V GND 4.7F BUS ON/OFF ENB OUTB D+ USB .01F D Port 2 63F GND Data Data (Two Pair) to USB Controller Typical Two-Port Bus-Powered Hub UL Recognized Component Micrel, Inc. 1849 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 944-0970 MIC2536 Micrel Ordering Information Part Number Enable Temperature Range Package MIC2536-1BM Active High 40C to +85C 8-Lead SOP MIC2536-2BM Active Low 40C to +85C 8-Lead SOP MIC2536-1BMM Active High 40C to +85C 8-Lead MSOP MIC2536-2BMM Active Low 40C to +85C 8-Lead MSOP Pin Configuration MIC2536-x ENA OUTA 1 8 FLGA IN 2 7 FLGB GND 3 6 ENB OUTB 4 5 8-Lead SOP (M) 8-Lead MSOP (MM) Pin Description Pin Number Pin Name Pin Function 1 ENA Enable A (Input): Channel A control input. Active high (1) or active low (2) input. 2 FLGA Flag A: (Output): Channel A open-drain fault flag output. Indicates overcurrent or thermal shutdown conditions. Overcurrent conditions must last longer than t in order to assert FLG. D 3 FLGB Flag B (Output): Channel B open-drain fault flag output. Indicates overcur- rent or thermal shutdown conditions. Overcurrent conditions must last longer than t in order to assert FLG. D 4 ENB Enable B (Input): Channel B control input. Active high (1) or active low (2) input. 5 OUTB Output B: Channel B switch output. 6 GND Ground 7 IN Positive Switch and Logic Supply Input 8 OUTA Output A: Channel A switch output. MIC2536 2 March 2000