IMP2527

The IMP2524 and IMP2527 are complete power management solutions for bus-powered and self-powered USB hubs. Each device contains four independent power switches and fault detection logic. The IMP2524 channel resistance is a low 140mΩ maximum and the IMP2527 channel resistance is 300Ω maximum. Both device operate with voltage inputs from 2.7V to 5.5V

The IMP2524/2527 conform to the new USB 1.1 standard. Fault current is limited to 750mA typically, and a flag output for each switch conveys fault information to the local USB controller. The IMP252x "Soft-Start" function of IMP2527 ramps the ON-current to eliminate any excessive voltage drop on the input side that could occur when capacitive loads are charged. Self-monitoring features of IMP2527 include thermal shutdown to prevent catastrophic switch failure from high-current loads and undervoltage lockout (UVLO) that insures that the device remains OFF unless there is sufficient supply voltage present.

The switch Enable input logic can interface with both 3.3V and 5V logic. Both active-HIGH (-1 devices) and active-LOW (-2 devices) enable logic versions are available. Supply current is a low 0.75µAwhen disabled and just 110µA when enabled

The quad IMP2524/7 devices are available in 16-pin DIP and 16-pin SO packages and are pin compatible replacements for the Micrel MIC2524-1/-2 and MIC2527-1/2 devices. IMP offers a complete family of USB power management products. For single-switch applications see the IMP2525 and IMP2525A data sheets. The single-switch IMP2525A features a 0.07Ω switch resistance. For dual-switch applications, refer to the IMP2526 data sheet.