Silicon Laboratories SI2494/39, SI2493/57/34/15/04 manual Introduction, Functional Block Diagram

AN93

Si2493/57/34/15/04 (Revision D) and Si2494/39 Modem Designer’s Guide

1. Introduction

The Si2494/93/57/39/34/15/04 ISOmodem chipset family consists of a 38-pin QFN (Si2494/39) or 24-pin TSSOP (Si2493/57/34/15/04) or 16-pin SOIC (Si2493/57/34/15/04) low-voltage modem device, and a 16-pin SOIC line- side DAA device (Si3018/10) connecting directly with the telephone local loop (Tip and Ring). This modem solution is a complete hardware (controller-based) modem that connects to a host processor through a UART, parallel or SPI interface. Parallel and EEPROM interfaces are available only on the 38-pin QFN or 24-pin TSSOP package option. Refer to Table 4, “ISOmodem Capabilities,” on page 10 for available part number, capability and package combinations. Isolation is provided by Silicon Laboratories’ isolation capacitor technology, which uses high-voltage capacitors instead of a transformer. This isolation technology complies with global telecommunications standards including FCC, ETSI ES 203 021, JATE, and all known country-specific requirements.

Additional features include programmable ac/dc termination and ring impedance, on-hook and off-hook intrusion detection, Caller ID, loop voltage/loop current monitoring, overcurrent detection, ring detection, and the hook- switch function. All required program and data memory is included in the modem device. When the modem receives a software or hardware reset, all register settings revert to the default values stored in the on-chip program memory. The host processor interacts with the modem controller through AT commands used to change register settings and control modem operation. Country, EMI/EMC, and safety test reports are available from Silicon Laboratories representatives and distributors.

This application note is intended to supplement the Si2494/39 Revision A, Si2493 Revision D, and the Si2457/34/ 15/04 Revision D data sheets. It provides all the hardware and software information necessary to implement a variety of modem applications, including reference schematics, sample PCB layouts, AT command and register reference, country configuration tables, programming examples and more. Particular topics of interest can be easily located through the table of contents or the comprehensive index located at the back of this document.

	XTI	XTO
CLKOUT	PLL
	Clocking
EESD	EEPROM	Data Bus
EECLK
	Interface
EECS
					C1	Si3018/10
RXD
TXD
CTS	UART	Controller					To Phone
RTS			DSP	DAA
	Interface				C2		Line
DCD				Interface
ESC						AOUT
RI						AOUTb
CS
WR	Parallel
RD				ROM
	Interface
A0
D0-D7				RAM
SDI		Program Bus
	SPI
SDO
SCLK	Interface					FSYNC
SS				Si3000		SDO
INT				Interface		SDI
						MCLK
RESET

Figure 1. Functional Block Diagram

Rev. 1.3 8/11 Copyright © 2011 by Silicon Laboratories AN93

This information applies to a product under development. Its characteristics and specifications are subject to change without notice.