USB Transceiver 1TR 16-Pin SOIC

TSS721A is a single chip transceiver developed for Meter-Bus standard (EN1434-3) applications.The TSS721A interface circuit adjusts the different potentials between a slave system and the Meter- Bus master. The connection to the bus is polarity independent and supports full galvanic slave isolation with optocouplers. The circuit is supplied by the master via the bus. Therefore, this circuit offers no additional load for the slave battery. A power-fail function is integrated. The receiver has dynamic level recognition, and the transmitter has a programmable current sink. A 3.3-V voltage regulator, with power reserve for a delayed switch off at bus fault, is integrated.

Meter-Bus Transceiver (for Slave) Meets Standard EN1434-3

Receiver Logic With Dynamic Level Recognition

Adjustable Constant-Current Sink via Resistor

Polarity Independent

Power-Fail Function

Module Supply Voltage Switch

3.3-V Constant Voltage Source

Remote Powering

Up to 9600 Baud in Half Duplex for UART Protocol

Slave Power Support

• Supply From Meter-Bus via Output VDD
• Supply From Meter-Bus via Output VDD or From Backup Battery
• Supply From Battery – Meter-Bus Active for Data
  Transmission Only