Silicon Laboratories Si2493 - User Manual

Rev. 1.4 11/13 Copyright © 2013 by Silicon Laboratories AN93
AN93
Si2493/57/34/15/04 (Revisions D and D1) and Si2494/39
(Revisions A and A1) 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/A1, Si2493 Revision D/D1, and the
Si2457/34/15/04 Revision D/D1 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.
Figure 1. Functional Block Diagram
UART
Interface
Parallel
Interface
DSP
DAA
Interface
ROM
PLL
Clocking
XTI XTO
CLKOUT
INT
RESET
C1
To Phone
Line
AOUT
Data Bus
Controller
Si3018/10
RXD
TXD
CTS
RTS
DCD
ESC
RI
CS
WR
RD
A0
D0-D7
Program Bus
RAM
EEPROM
Interface
EESD
EECLK
EECS
C2
Si3000
Interface
FSYNC
SDO
SDI
MCLK
SPI
Interface
SDI
SDO
SCLK
SS
AOUTb

Summary

1. Introduction

1.1. Selection Guide

Provides a guide to selecting the appropriate ISOmodem part number based on features.

2. Modem (System-Side) Device

2.1. Resetting the Device

Details the procedures for resetting the ISOmodem, including hardware and software resets.

2.2. System Interface

Describes the digital interface options: UART, parallel, and SPI.

2.4. Low-Power Modes

Explains the Power-Down, Wake-on-Ring, and Sleep modes for power conservation.

3. DAA (Line-Side) Device

3.1. Hookswitch and DC Termination

Covers programmable settings for DC impedance, current limiting, and loop current.

3.5. Line Voltage and Loop Current Sensing

Describes methods for measuring line voltage and loop current using U79 and U63 registers.

4. Hardware Design Reference

4.1. Component Functions

Details the functions of external support circuitry for the ISOmodem and Si3018/10.

4.4. Layout Guidelines

Provides critical recommendations for PCB layout to ensure proper performance and compliance.

5. Modem Reference Guide

5.4. AT Command Set

Presents the AT commands divided into control and configuration commands for modem operation.

5.7. U Registers

Describes the 16-bit user-access registers (U registers) for configuration and features.

6. Programming Examples

6.1. Quick Reference

Summarizes modem functions, features, hardware pins, AT commands, and registers.

6.2. Country-Dependent Setup

Explains how to configure the ISOmodem for different countries using AT commands.

7. Handset, TAM, and Speakerphone Operation

7.1. Software Reference

Covers V.253 AT Commands, <DLE> commands, and U registers for voice modes.

7.3. Si3000 Configuration

Details the configuration of the Si3000 codec for various system voice modes.

7.7. Speakerphone

Describes speakerphone functionality, including calibration and configuration.

8. Security Protocols

8.1. Implementing the SIA Protocol

Details the SIA protocol for alarm panel and central station communication.

8.2. Implementing the Ademco Contact ID Protocol

Explains the Ademco Contact ID protocol for security applications.

9. Chinese ePOS SMS

9.1. Introduction

Introduces SMS support in ePOS connections and the SMS message frame format.

9.2. SMS AT Command Set

Lists AT commands for controlling SMS transmission and reception.

10. Testing and Diagnostics

10.1. Prototype Bring-Up (Si3018;10)

Provides tips for debugging initial prototypes and isolating problems.

10.2. Self Test

Describes built-in self-test features for system functionality and loopback modes.

10.4. Compliance Testing

Details commands and configurations for regulatory compliance testing.

Appendix A-EPOS APPLICATIONS

5.13.1. EPOS Fast Connect

Describes fast connect modes for EPOS terminals to reduce transaction time.

Appendix B-Line Audio Recording

When to Use Audio Recording

Guidance on when audio recording is effective for debugging modem negotiation issues.

Hardware Setup

Details the hardware setup required for connecting to the phone line and PC audio input.

Appendix C-Parallel;SPI Interface Software Implementation

Software Description

Describes software interface requirements for parallel or SPI modes with a C8051F12x MCU.

Silicon Laboratories Si2493 Specifications

General

Category	Modem
Manufacturer	Silicon Laboratories
Model	Si2493
Interface	Serial
Data Rate	Up to 56 kbps
Operating Voltage	3.3 V
Temperature Range	-40°C to +85°C
Modulation	V.21