LE9540CUQC

Telecom Overview

The LE9540CUQC is a dual-channel Subscriber Line Interface Circuit (SLIC) from Microchip Technology, designed for short-loop VoIP applications. It operates on a single 3.3V supply and supports up to -100V ringing battery voltage. The device integrates two independent channels with serial interface control, providing battery feed, power ringing, and supervision functions. Key electrical parameters include a maximum VBAT of -100V, operating temperature range of -40°C to 85°C, and a 40-pin QFN package.

Telecom Feature Summary

• Dual architecture integrating two independent SLIC channels for voice loop supervision
• Serial interface with reset for operational control and status reporting
• Common protection reference output for shared or per-channel protection devices
• Eight channel-independent operating states including scan, active, and ringing

Telecom Applications

• Optimized design for Broadcom BCM3383/85 SoCs
• Short loop residential gateways
• Wide-band POTS loop applications

Telecom Procurement Notes

Verify the specific suffix 'CUQC' against the manufacturer's current datasheet DS00003645A to confirm package type and environmental rating. Ensure compatibility with the required -100V battery supply specification. Check for any recent Product Change Notifications regarding marking or assembly changes before finalizing procurement.

Telecom Selection Notes

Select this component when interfacing with Broadcom SoCs requiring dual-channel SLIC functionality. Ensure the design accommodates the 40-QFN package thermal requirements by connecting the exposed pad to a ground plane. Verify that the application requires a maximum -100V battery supply; if -145V is needed, consider the LE9540D variant.

Telecom Part Context

The LE9540CUQC belongs to the VE950 Series of Subscriber Line Interface Circuits. It is part of a family optimized for cable modem and residential gateway applications. The 'C' suffix typically denotes the -100V battery rating, distinguishing it from the 'D' variant which supports higher voltages.

Telecom Replacement Considerations

LE9540DUQC: Same package but supports up to -145V battery voltage.

Telecom FAQ

What is the default power-up state of the LE9540CUQC?

The default power-up state is Active Forward with low DC current limit (ILL) and the test switch turned off.

How is thermal management handled in the LE9540CUQC?

The device features thermal shutdown protection with hysteresis. The exposed pad must be connected to a ground plane on the PCB for thermal conduction and electrical grounding.

What types of signals can be used for the RINGP and RN inputs?

The RINGP and RN inputs can accept sine waves or filtered square waves to produce sine or trapezoidal output signals for power ringing.