AFE1124E/1K

Analog Front End (AFE) Overview

The AFE1124E/1K is an obsolete HDSL/MDSL analog front end manufactured by Texas Instruments. It integrates transmit and receive sections to interface digital signal processors with telephone lines via a compromise hybrid and line transformer. The device operates on a single +5V analog supply and supports digital logic from 3.3V to 5V. It handles data rates from 64kbps to 1168kbps, generating 2B1Q symbols for transmission and digitizing received signals using a delta-sigma ADC. Key specifications include a typical power dissipation of 250mW at 3.3V digital supply, a 14-bit resolution, and operation within a temperature range of -40°C to +85°C.

Analog Front End (AFE) Feature Summary

• Integrated HDSL/MDSL analog front end supporting scalable data rates from 64kbps to 1168kbps
• Transmit section generates filtered 2B1Q analog symbols with a differential line driver outputting up to 13.5dBm
• Receive section features a fourth-order delta-sigma ADC with 14-bit resolution and programmable gain amplifier (0dB to +12dB)
• Six-wire serial digital interface for independent transmit and receive clock synchronization

Analog Front End (AFE) Applications

• HDSL (High bit rate Digital Subscriber Line) systems
• MDSL (Medium speed Digital Subscriber Line) applications
• RADSL (Rate Adaptive DSL) implementations
• E1 and T1 telecommunication interfaces

Analog Front End (AFE) Procurement Notes

The AFE1124E/1K is classified as NRND (Not Recommended for New Designs) and is obsolete. Verify current availability through authorized distributors or surplus suppliers. Designers should confirm lead times and authenticity, as the component is no longer recommended for new production designs by Texas Instruments.

Analog Front End (AFE) Selection Notes

Select this component only for maintenance or replacement of existing HDSL/MDSL equipment. Ensure the system design accommodates the specific timing requirements of the six-wire serial interface and the external compromise hybrid connection. Verify that the application does not require new design approval, as the device is obsolete.

Analog Front End (AFE) Part Context

The AFE1124 was originally developed by Burr-Brown Corporation before its acquisition by Texas Instruments. It is housed in a 28-pin SSOP package. The '/1K' suffix indicates a tape and reel packaging configuration. The device simplifies xDSL system design by consolidating active analog circuitry required for line interfacing.

Analog Front End (AFE) Replacement Considerations

No direct public substitute part numbers are documented for this obsolete component. Engineers must evaluate modern integrated transceivers or discrete solutions that meet E1/T1/HDSL specifications and pin compatibility requirements.

Analog Front End (AFE) FAQ

What is the input coding format for the receive channel?

The receive channel outputs 14-bit digital data coded in two's complement format.

How does the AFE1124 handle echo cancellation?

It performs first-order analog echo cancellation by subtracting the signal from the hybrid input (rxHYB) from the line input (rxLINE).

What are the power supply requirements?

The analog supply (AVDD) requires +5V (4.75V to 5.25V), while the digital supply (DVDD) accepts 3.3V to 5V.