LE9551CMQCT

Telecom Overview

The LE9551CMQCT is a single-channel high-voltage ringing Subscriber Line Interface Circuit (SLIC) manufactured by Microchip Technology. It operates with a –100 V ringing battery and is functionally equivalent to one channel of the LE9540 device. The component is housed in a 4x5 mm 28-pin QFN package, optimized for single-channel applications. It supports serial interface control and status reporting, including reset functionality. Electrical specifications include a power consumption of up to 236 mW in ring state at no load, a longitudinal-to-metallic balance of 52 dB, and a Power Supply Rejection Ratio (PSRR) of 40 dB across the 500 Hz to 3000 Hz range.

Telecom Feature Summary

• Optimized for integration with Broadcom BCM338x/BCM339x SoCs in short-loop residential gateways
• Supports 7-kHz wideband applications and GR909 testing standards
• Includes thermal shutdown protection with hysteresis and integrated test load switch
• Provides DC loop closure, ring trip, and ring-ground detection capabilities

Telecom Applications

• Short-loop Cable voice loops
• Residential gateways
• Voice line circuits

Telecom Procurement Notes

Verify the specific ordering suffix 'CMQCT' against the manufacturer's current documentation to confirm the tape and reel packaging format and commercial temperature grade. Ensure compatibility with the intended PCB footprint, as this part utilizes a 28-pin QFN package distinct from other variants in the series.

Telecom Selection Notes

Select the LE9551CMQCT when a compact single-channel solution is required for short-loop applications. This variant provides a –100 V ringing battery capability, distinguishing it from the –145 V rated LE9551DMQCT. Consider the 28-pin QFN form factor for space-constrained designs compared to the larger 40-pin packages available for dual-channel implementations.

Telecom Part Context

This component belongs to the VE950 Series of Ringing Subscriber Line Interface Circuits produced by Microsemi Corporation, now part of Microchip Technology. The LE9551 series serves as a functional equivalent to individual channels within the LE9540 family, offering specialized optimization for residential gateway architectures.

Telecom Replacement Considerations

The LE9541CUQCT is documented as a similar replacement option. Note that the LE9541 utilizes a 40-pin QFN package, requiring significant PCB layout adjustments compared to the 28-pin LE9551CMQCT.

Telecom FAQ

What is the maximum ringing battery voltage supported by the LE9551CMQCT?

The LE9551CMQCT supports an up to –100 V ringing battery.

How does the LE9551 relate to the LE9540 device?

The LE9551 is functionally equivalent to one channel of the LE9540 device.

Does the LE9551CMQCT support wideband audio applications?

Yes, the high voltage high bandwidth design supports 7-kHz wideband applications.