USB transceiver touts 7500-V isolation

A USB reinforced isolator, Linear Technology’s LTM2894 guards against ground-to-ground voltage differentials and large common-mode transients. It separates grounds by isolating a pair of USB signal transceivers using internal signal isolation, providing 7500 VRMS isolation for 1 minute, plus common-mode rejection of greater than 50 kV/µs.

In addition, the LTM2894 µModule transceiver withstands up to 1000 VRMS continuously, and its 17.4-mm creepage distance allows medical equipment to operate from mains voltages greater than 250 VRMS, while achieving a 2-MOPP rating. ESD protection permits the part to withstand up to ±20 kV HBM on the USB transceiver interface pins to local supplies and ±20 kV through the isolation barrier to supplies without latchup or damage.

Useful for a variety of USB hub, host, and bus isolation applications, the LTM2894 operates at USB 2.0 full speed (12 Mbps) and low speed (1.5 Mbps). Suspend mode monitors for inactivity and reduces VBUS current to under 2.0 mA. Integrated downstream-facing pull-down resistors and upstream-facing pull-up resistors are automatically configured to match the speed of the downstream device, enabling the LTM2894 to monitor and report bus speeds to the host.