SI2457-C-FT Silicon Laboratories Inc, SI2457-C-FT Datasheet - Page 16

• Manufacturer Part Number: SI2457-C-FT
• Description: IC ISOMODEM SYSTEM-SIDE 24TSSOP
• Manufacturer: Silicon Laboratories Inc

Specifications of SI2457-C-FT

• Package / Case: 24-TSSOP
• Mfg Application Notes: SI2493/57/34/15/04, Appl Note AN93
• Data Format: V.21, V.22, V.23, V.32, V.34, V.90, Bell 103, Bell 212A
• Baud Rates: 56k
• Interface: Parallel, UART
• Voltage - Supply: 3 V ~ 3.6 V
• Mounting Type: Surface Mount
• Operating Frequency: 4.92 MHz
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 3 V
• Supply Current: 26 mA
• Operating Temperature Range: 0 C to + 70 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

Si2457/34/15/04-Si3008
4. Functional Description
The Si2457/34/15/04 ISOmodem® utilizing the Si3008
line-side device is a complete embedded modem
chipset with integrated direct access arrangement
(DAA). Available in two small packages, this solution
includes a DSP data pump, modem controller, on-chip
RAM and ROM, codec, DAA, analog output, and 27
MHz clock input.
The Si2457/34/15/04 accepts standard modem AT
commands and provides connect rates up to 56/33.6/
14.4/2.4 kbps full-duplex over the Public Switched
Telephone Network (PSTN). The Si2457/34/15/04
features a complete set of modem protocols including all
ITU-T standard formats up to 56 kbps.
To provide the most flexibility, the Si2457/34/15/04
ISOmodem system-side device is offered in either a 24-
pin TSSOP or a 16-pin SOIC package. The 16-pin
version
ISOmodem and is recommended for most applications.
The 16-pin version does not support the parallel,
EEPROM or voice codec interface. If these features are
required, customers should use the 24-pin version.
The ISOmodem provides numerous additional features
for embedded modem applications. The modem includes
full type I and type II caller ID detection and decoding, call
progress monitoring through standard result codes, error
correction, data compression, an optional EEPROM or
parallel interface, autobaud, and fast connect modes. In
addition, because the Si2457/34/15/04 ISOmodem
integrates the DAA, analog features, such as parallel
phone, line-in-use, and overcurrent detection are
included.
This device is ideal for embedded modem applications
due to its simple host interface, small board space, and
low power consumption. The Si2457/34/15/04 solution
utilizing Silicon Laboratories’ Si3008 proprietary DAA can
be programmed to meet international requirements and
is compliant with FCC, JATE, and numerous other
country-specific PTT specifications as shown in Table 8.
Also, the Si3008 meets the most stringent global
requirements
immunity, lightning surges, and safety.
The Si2457/34/15/04 allows for rapid integration into
existing modem applications by providing a serial
interface that can directly communicate to either a
microcontroller via a UART interface or a PC via an RS-
232 port. This interface allows for PC evaluation of the
modem
commands using standard terminal software. The
Si2457/34/15/04 also provides an 8-bit parallel port.
16
is
immediately
footprint-compatible
for
out-of-band
upon
powerup
energy,
with
via
the
emissions,
Preliminary Rev. 0.7
the
Si2401
AT
4.1. Serial Interface
The Si2457/34/15/04 supports asynchronous serial
communication with data terminal equipment (DTE) at
rates up to 307.2 kbps with the standard serial UART
format. Upon powerup, the UART baud rate is
automatically detected using the autobaud feature.
The serial interface also provides a hardware pin, DCD
(data carrier detect), which remains low as long as the
ISOmodem is connected.
The INT interrupt pin can be programmed to alert the
host of changes to the interrupts listed in I/O Control 0
(U70).
To ensure backward compatability when using a 24-pin
system side option, if a pulldown resistor ≤10 kΩ is
placed between D2 (Si2457/34/15/04, pin 18) and GND
(Si2457/34/15/04, pin 6), the DTE rate is set to a
19.2 kbps baud rate (see Table 9).
4.1.1. Autobaud
The Si2457/34/15/04 includes an automatic baud rate
detection feature that allows the host to start
transmitting data at any standard DTE rate from
300 bps to 307.2 kbps. This feature is enabled by
default.
4.2. Parallel Interface (24-Pin Version Only)
The Si2457/34/15/04 digital I/O can communicate via a
Argentina
Brazil
Canada
Chile
China
Colombia
Ecuador
Egypt
El Salvador
Guam
Hong Kong
Hungary
India
Indonesia
Japan
Jordan
Kazakhstan
*Note: Supported for loop currents > 20 mA.
Table 8. Country-Specific PTT Specifications
Country
Kuwait
Macao
Malaysia*
Mexico
Oman
Pakistan
Peru
Romania
Russia
Saudi Arabia
Singapore
Slovakia
Syria
Taiwan
UAE
USA
Yemen