SI2494-A-FM - 56 kbps V.92/V.34 ISOMODEM | Skyworks Solutions
MPN: SI2494-A-FM ✓ ActiveSI2494-A-FM Overview
An ISOMODEM is an integrated modem chipset solution that combines modem signal processing with telephone-interface functions and associated digital control. Within the broader semiconductor hierarchy, the SI2494-A-FM belongs to the modem controller and network-interface controller class, rather than to a conventional general-purpose microprocessor or standalone analog line transceiver. Its V.34/V.92 support is intended for interoperable data transmission over switched telephone-network and compatible access lines.
The SI2494-A-FM is identified as a system-side ISOmodem product and is associated with a 56 kbps data rate. The device family is described in the product documentation as a V.92 and V.34 ISOMODEM with Global DAA, while the 38-pin QFN package is specified as 5 x 7 mm. The exposed-pad package provides a direct thermal path to the PCB and should be connected according to the package land pattern and thermal design guidance.
Typical communications uses include centralized modem modules, customer-premises equipment, telephone-line data products, industrial data links, and legacy serial-access systems that require V.92/V.34 interoperability. The controller should be paired with the appropriate line-side interface, isolation barrier, power regulation, crystal or clock network, and host controller required by the end product. Its 56 kbps class is substantially higher than V.34 operation while retaining compatibility with the older modem standard.
Design work should begin with the manufacturer’s SI2494/93/57/39/34/15/04 ISOmodem chipset-family guidance. Verify clock, supply sequencing, line-side signaling, exposed-pad soldering, and DAA implementation against the final modem architecture. For an existing board, confirm the 38-QFN 5 x 7 mm footprint, pin functions, thermal pad arrangement, and software compatibility before assigning a replacement role.
This page combines package, protocol, compliance, and application information with practical design guidance and a structured comparison framework. It is intended to help engineers identify whether the SI2494-A-FM fits a telephone-data product, understand its integration constraints, and plan a qualified sourcing or replacement review.
Drop-in alternatives for SI2494-A-FM — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
No drop-in alternatives available for this product.
Request AlternativesSI2494-A-FM Specifications
| Product Type | ISOMODEM controller and processor IC |
| Modem Standards | V.92 and V.34 |
| Data Rate | 56 kbps |
| Product Role | System-side ISOmodem |
| Telephone Interface | Global DAA support |
| Package | 38-pin QFN (5 x 7 mm) |
| Package Construction | QFN with exposed pad |
| Mounting Type | Surface mount |
| Lead-Free Status | Lead free |
| RoHS Status | RoHS compliant |
SI2494-A-FM qfn with exposed pad Pin Configuration Guide
Pin configuration for SI2494-A-FM (qfn with exposed pad package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for SI2494-A-FM.
Refer to the datasheet for full pin configuration.
Typical Applications
SI2494-A-FM is suitable for 6 applications: System-Side Telephone Modems, Customer Premises Equipment, Industrial Telephone-Line Links, Remote Diagnostics Terminals, Legacy Serial-Access Products, Telecommunications Support Equipment.
System-Side Telephone Modems
The SI2494-A-FM is designed for the system-side role in a V.92 and V.34 modem arrangement operating at 56 kbps. It can serve as the central modem controller in equipment that must retain V.34 interoperability while supporting the higher V.92 rate. Integration requires the correct line-side interface, Global DAA implementation, clocking, power rails, and host-control arrangement. Because the controller is packaged in a 38-QFN 5 x 7 mm footprint, it supports compact equipment layouts while requiring careful exposed-pad assembly and thermal design.
Recommended
Customer Premises Equipment
The SI2494-A-FM fits customer-premises equipment that transfers data over a telephone access line while supporting V.92 and V.34 sessions. Its 56 kbps modem class is appropriate for embedded access products that must communicate with both newer V.92 equipment and legacy V.34 modems. The board designer must provide the selected DAA, isolation barrier, line-side circuitry, host interface, and clock source required by the product architecture. Confirm operating-temperature and regulatory requirements before deploying it outside controlled indoor environments.
Recommended
Industrial Telephone-Line Links
The SI2494-A-FM can support legacy telephone-line data connectivity in industrial equipment that must interoperate with V.92 and V.34 modem services. The 56 kbps rate makes it relevant for supervisory data, configuration transfer, remote diagnostics, and low-bandwidth equipment control rather than high-throughput networking. Its use requires a complete modem circuit around the controller, including Global DAA implementation and appropriate line protection. Environmental limits, isolation, surge protection, and regulatory requirements should be reviewed for each installation environment.
Recommended
Remote Diagnostics Terminals
The SI2494-A-FM can form the modem section of a remote diagnostics terminal requiring compatibility with both V.92 and V.34 equipment. A 56 kbps V.92 session can reduce transfer time compared with a legacy-only terminal, while V.34 support preserves connection options across mixed infrastructure. The implementation must support the equipment’s required dialing, DAA, and telephone-line behavior. Firmware, host-driver, and line-interface validation are especially important when the same terminal must communicate with equipment produced during different modem generations.
Recommended
Legacy Serial-Access Products
The SI2494-A-FM is suitable for legacy serial-access products that require a standardized modem path rather than a general-purpose serial interface. Its V.34 and V.92 capabilities provide compatibility with established remote-access infrastructure at a 56 kbps modem rate. Designers should use the manufacturer’s chipset-family application information to select the required companion interfaces and confirm clock and signal timing. The package’s exposed pad should be tied to the recommended ground plane, and its assembly process should follow the stated QFN land-pattern and solder-reflow requirements.
Recommended
Telecommunications Support Equipment
The SI2494-A-FM can be incorporated into telecommunications support equipment used to test or maintain V.92 and V.34 modem connections. Dual-standard support helps service teams work across legacy and higher-rate access endpoints, while the 56 kbps rating defines the modem-session class rather than the physical data-port speed. A practical design must include the required Global DAA, line-side circuitry, isolation, clocking, and host interface. Validate interoperability using the actual line conditions and remote equipment expected in service.
Recommended
Engineering reference data for SI2494-A-FM — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product |
|---|---|
| Brand | Skyworks Solutions |
| Package | 38-pin QFN (5 x 7 mm) with exposed pad |
| Product Type | System-side ISOMODEM controller and processor IC |
| Modem Standards | V.92 and V.34 |
| Data Rate | 56 kbps |
| Telephone Interface | Global DAA support |
| Lead-Free Status | Lead free |
| RoHS Status | RoHS compliant |
Key Differentiators
- Combines V.92 and V.34 in one system-side modem controller (vs Generic 56 kbps modem controller)
- Provides Global DAA capability (vs Modem controller without Global DAA)
- Uses a compact 38-QFN footprint (vs Larger packaged modem implementation)
Design Notes
Use the exact 38-pin QFN 5 x 7 mm land pattern from the manufacturer datasheet. Place the exposed-pad connection and thermal vias directly beneath the device, keep high-current supply returns close to their pins, and avoid placing sensitive telephone-line routing beneath the modem package. Validate the stencil, paste volume, and reflow profile against the package construction.
Separate the modem processing section from sensitive line-side and isolation circuitry. Keep clock routing short and away from switching nodes and high-energy telephone-interface paths. Provide a low-impedance ground reference for the exposed pad and follow the recommended decoupling arrangement. Review signal returns to prevent the Global DAA and telephone-line subsystem from injecting noise back into the controller.
Do not select a replacement solely because it is labeled as a 56 kbps modem. Verify all 38 pin assignments, V.92 and V.34 support, Global DAA behavior, clocking, supply levels, exposed-pad connection, and host-driver expectations. A candidate with the same nominal rate but a different pinout or firmware architecture is not a drop-in replacement and requires board-level redesign.
Implement the manufacturer-specified supply rails and decoupling before tuning modem performance. The SI2494-A-FM is a controller within a larger telephone-access design, so power integrity depends on the regulator, DAA, isolation barrier, and line-side circuitry as a complete system. Confirm supply sequencing, startup behavior, and operating-current requirements against the relevant datasheet sections.
Compliance Information
Lead-free and RoHS-compliant construction are identified in the component documentation. Other environmental, automotive, and material-compliance classifications are not stated.
