LE57D122BTCT

Telecom Overview

The LE57D122BTCT is a dual-channel Subscriber Line Interface Circuit (SLIC) from the Le5712 family, manufactured by Microchip Technology. It operates with a +5 V logic supply and a negative battery supply ranging from -39 V to -60 V. The device supports loop start and ground start configurations, providing over 20 mA into a 2000 Ω load from -48 V. It features on-chip thermal management, per-channel fault detection, and programmable thresholds for off-hook and ring-trip states. Packaged in a 44-pin eTQFP with a 12 x 12 mm footprint, it enables high-density line card designs.

Telecom Feature Summary

• Dual-channel integration supporting both loop start and ground start subscriber lines within a single compact package.
• On-chip thermal management capability that off-loads power dissipation to external resistors during active states.
• Comprehensive supervision including per-channel fault detection, thermal shutdown protection, and programmable off-hook and ring-trip thresholds.

Telecom Applications

• High-density POTS line cards for central offices and digital loop carriers
• Subscriber line interfaces for markets requiring specific loop start or ground start protocols
• Telecommunications equipment designed for low-power operation with reduced component counts

Telecom Procurement Notes

Verify the manufacturer origin as Zarlink Semiconductor devices are now managed by Microchip Technology. Confirm the ordering suffix 'T' indicates tape and reel packing. Ensure the specific variant matches the required reverse polarity performance level (-63 dB) for the target application market.

Telecom Selection Notes

Select this device when high channel density is required due to its small 44-pin eTQFP footprint. Consider the integrated thermal management if operating near maximum current limits. Verify compatibility with the system's logic voltage levels, as inputs are compatible with 3.3 V controllers.

Telecom Part Context

This component belongs to the Le5712 series of dual SLICs. It is functionally similar to the Le57D121BTC but offers different transmission characteristics (-63 dB vs -53 dB). It is designed to work in conjunction with QLSLAC codec devices for complete line circuit solutions.

Telecom Replacement Considerations

The LE57D121BTC is a direct pin-compatible alternative within the same family, differing primarily in transmission specifications. Designers should verify if the specific attenuation requirements of their application align with either model before substitution.