Description
The ST7540 is a Half Duplex synchronous/asynchronous FSK Modem designed for power line communication network applications. It operates from a single supply voltage and integrates a line driver and two linear regulators for 5V and 3.3V. The device operation is controlled by means of an internal register, programmable through the synchronous serial interface. Additional functions as watchdog, clock output, output voltage and current control, preamble detection, time-out and band in use are included. Realized in Multipower BCD5 technology that allows to integrate DMOS, Bipolar and CMOS structures in the same chip.

General features
■ Half-duplex frequency shift keying (FSK) transceiver
■ Integrated power line driver with programmable voltage and current control
■ Programmable mains access:
   – Synchronous
   – Asynchronous
■ Single supply voltage (from 7.5V up to 13.5V)
■ Very low power consumption (Iq = 5mA)
■ Integrates 5V voltage regulator (up to 50mA) with short circuit protection
■ Integrated 3.3V voltage regulator (up to 50mA) with short circuit protection
■ 3.3V or 5V digital supply
■ 8 Programmable transmission frequencies
■ Programmable baud rate up to 4800BPS
■ Receiving sensitivity up to 250µVRMS
■ Suitable for applications in accordance with EN 50065 Cenelec specification
■ Carrier or preamble detection
■ Band in use detection
■ Programmable control register
■ Watchdog timer
■ 8 or 16 Bit header recognition
■ ST7537 and ST7538 compatible
■ UART/SPI host interface