V

3.3 V

VDD

REF1

7 V

ECHO

CS2

TC1

CS1

BR

TC3

TC2

TC4

BAT

CS3

VF

RIDD

STC

VS

VDD

I

STC_use

I

CI1

I

STC

I

VDD

R

VS

I

CS3

VB

PF

BUSL1

TX

GND

RIS

BUSL2

TXI

RX

RXI

SC

REF2

1.3 V

I

MS

I

BUS

I

CI2

TSS521

www.ti.com

SLAS980 – SEPTEMBER 2013

Meter-Bus Transceiver

1

FEATURES

APPLICATIONS

•

Meter-Bus Transceiver (for Slave) Meets

•

E-metering

Standard EN1434-3

•

Advanced Metering Infrastructure (AMI)

•

Receiver Logic With Dynamic Level

•

Water Meters

Recognition

•

Gas Meters

•

Constant-Current Sink Adjustable By Resistor

•

Heat Meters

•

Polarity Independent

•

Power-Fail Function

DESCRIPTION

The TSS521 device is a single-chip transceiver

•

Module Supply Voltage Switch

developed

for

Meter-Bus

standard

(EN1434-3)

•

3.3-V Constant Voltage Source

applications.

•

Up to 9600 Baud in Half Duplex for UART

The TSS521 interface circuit adjusts the different

Protocol

potentials between a slave system and the Meter-Bus

•

Slave Power Support

master. The connection to the bus is polarity

–

Supply From Meter-Bus by Output VDD

independent and supports full galvanic slave isolation

with optocouplers.

–

Supply From Meter-Bus by Output VDD or

From Backup Battery

The circuit is supplied by the master through the bus.

Therefore, this circuit offers no additional load for the

–

Supply From Battery – Meter-Bus Active for

slave battery. A power-fail function is integrated.

Data Transmission Only

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.

Functional Schematic

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Copyright © 2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.