MIC2545A/2549A Programmable Current-Limit High-Side Switch General Description Features The MIC2545A and MIC2549A are integrated high-side 2.7V to 5.5V input power switches optimized for low-loss DC power switching Adjustable current-limit up to 3A and other power-management applications, including Reverse current flow blocking advanced configuration and power interface (ACPI). The 90A typical on-state supply current MIC2545A/49A is a cost-effective, highly-integrated solution that requires few external components to satisfy 1A typical off-state supply current USB and ACPI requirements. 50m maximum on-resistance Load current management features include a precision, Open-drain fault flag resistor-programmable output current-limit and a soft-start Thermal shutdown circuit, which minimizes inrush current when the switch is Thermal-shutdown output latch (MIC2549A) enabled. Thermal shutdown, along with adjustable current- 2ms (slow) soft-start turn-on, fast turnoff limit, protects the switch and the attached device. Available with active-high or active-low enable The MIC2545A/49As open-drain flag output is used to indicate current-limiting or thermal shutdown to a local controller. The MIC2549A has an additional internal latch Applications which turns the output off upon thermal shutdown, providing robust fault control. The enable signal is USB power distribution compatible with both 3V and 5V logic, and is also used as PCI Bus Power Switching the thermal shutdown latch reset for the MIC2549A. Notebook PC The MIC2545A and MIC2549A are available in active-high ACPI power distribution and active-low enable versions in 8-pin DIP, SOIC, and PC card hot swap applications TSSOP packages. Inrush current-limiting Data sheets and support documentation can be found on Micrels web site at: www.micrel.com. Typical Application Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC2545A/2549A Ordering Information Part Number Enable Temperature Range Latch Pb-Free Package MIC2545A-1BM Active HIGH 40C to +85C No No 8-Pin SOP MIC2545A-1BN Active HIGH No No 8-Pin DIP 40C to +85C MIC2545A-1BTS Active HIGH 40C to +85C No No 14-Pin TSSOP MIC2545A-2BM Active LOW No No 8-Pin SOP 40C to +85C MIC2545A-2BN Active LOW 40C to +85C No No 8-Pin DIP MIC2545A-2BTS Active LOW No No 14-Pin TSSOP 40C to +85C MIC2545A-1YM Active HIGH 40C to +85C No Yes 8-Pin SOP MIC2545A-1YN Active HIGH No Yes 8-Pin DIP 40C to +85C MIC2545A-1YTS Active HIGH 40C to +85C No Yes 14-Pin TSSOP MIC2545A-2YM Active LOW 40C to +85C No Yes 8-Pin SOP MIC2545A-2YN Active LOW 40C to +85C No Yes 8-Pin DIP MIC2545A-2YTS Active LOW 40C to +85C No Yes 14-Pin TSSOP MIC2549A-1BM Active HIGH 40C to +85C Yes No 8-Pin SOP MIC2549A-1BN Active HIGH 40C to +85C Yes No 8-Pin DIP MIC2549A-1BTS Active HIGH 40C to +85C Yes No 14-Pin TSSOP MIC2549A-2BM Active LOW 40C to +85C Yes No 8-Pin SOP MIC2549A-2BN Active LOW 40C to +85C Yes No 8-Pin DIP MIC2549A-2BTS Active LOW 40C to +85C Yes No 14-Pin TSSOP MIC2549A-1YM Active HIGH Yes Yes 8-Pin SOP 40C to +85C MIC2549A-1YN Active HIGH 40C to +85C Yes Yes 8-Pin DIP MIC2549A-1YTS Active HIGH Yes Yes 14-Pin TSSOP 40C to +85C MIC2549A-2YM Active LOW 40C to +85C Yes Yes 8-Pin SOP MIC2549A-2YN Active LOW Yes Yes 8-Pin DIP 40C to +85C MIC2549A-2YTS Active LOW 40C to +85C Yes Yes 14-Pin TSSOP M9999-062711-A June 2011 2