Transceiver meets IEC 60601-1 medical standard with low EMI
An isolated RS485 uModule transceiver, the LTM885, is designed to guard again large ground-to-ground differentials. According to Linear Technology, many industrial, utility, medical, military, and intrinsic safety applications require isolation components with increased voltage and spatial separation for human safety. The LTM2885 provides 6500VRMS reinforced isolation between the logic level interface and the transceiver bus pins. This exceeds the IEC 60747 basic and reinforced isolation standards.
Creepage and clearance distances are greater than 14mm and distance through insulation (DTI) is greater than 0.2mm, enabling the transceiver to exceed many over-voltage category II and material group IIIA equipment requirements, including the provision of two means of patient protection (MOPP) for medical equipment (to IEC 60601-1).
The ±15kV ESD-protected RS485 transceiver operates at 20Mbit/s or low EMI 250kbit/s, with uninterrupted communication guaranteed for common mode transients up to 50kV/micro seconds. An internal, low EMI, DC/DC converter powers the transceiver and provides an isolated 1W supply output for powering external support components. Integrated selectable termination allows cables to be terminated, with the flexibility to add or remove termination anywhere on the bus via software control.
Operating from a 5V supply, the LTM2885 requires no additional external components, and is a self-contained μModule for isolated RS485 serial data communications.
The transceiver is offered in commercial, industrial and automotive versions, supporting operating temperature ranges from 0 to 70 degree C, –40 to +85 degree C, and –40 to +105 degree C, respectively. It is offered in a surface mount BGA, measuring 22 x 9.0 x 5.16mm. All ICs and passive components are housed in the RoHS-compliant package.