8T49N105ANLGI8

Overview

The IDT8T49N105I is a FemtoClock NG Universal Frequency Translator and Synthesizer designed for networking and communications applications. It generates output frequencies from 0.98MHz to 312.5MHz, with most frequencies supported up to 1,300MHz. The device features three operating modes: Frequency Synthesizer, High-Bandwidth Frequency Translator, and Low-Bandwidth Frequency Translator. It accepts differential inputs (LVPECL, LVDS, LVHSTL, HCSL) in the 8kHz–710MHz range or crystal inputs from 16MHz–40MHz. Key electrical parameters include an RMS phase jitter of 439fs at 155.52MHz (Low Bandwidth Mode) and 285fs at 400MHz (Synthesizer Mode). Power supplies support VCC/VCCA/VCCO configurations of 3.3V/3.3V/3.3V, 3.3V/3.3V/2.5V, or 2.5V/2.5V/2.5V.

Feature Summary

• Universal Frequency Translator / Synthesizer with zero ppm frequency translation capability
• Single differential output pair (Q, nQ) programmable as LVDS or LVPECL
• Two factory-programmed One-Time Programmable (OTP) default configurations selectable via CONFIG pin or I2C register
• Integrated alarm monitoring outputs for LOCK_IND, HOLDOVER, CLK_BAD, and XTAL_BAD conditions

Applications

• PCI Express and Computing systems requiring high-bandwidth frequency translation
• Networking and Communications equipment utilizing low-bandwidth jitter attenuation
• Line cards supporting multiple optional daughter cards with different clock requirements

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current datasheet to confirm package type and tape/reel specifications. Confirm RoHS compliance status and lead-free packaging details directly with Renesas Electronics or authorized distributors prior to procurement.

Selection Notes

Select this component when a single-output universal frequency translator is required with flexible input/output voltage levels. Ensure the application utilizes either the internal OTP configuration for fixed setups or implements I2C control for dynamic reconfiguration. Verify that the required output frequency falls within the supported divider ranges defined in Table 3 of the datasheet.

Part Context

This device belongs to the FemtoClock NG family of low phase noise clock generators. It serves as a general-purpose solution for translating and synthesizing clock signals in high-performance digital systems. The part integrates advanced PLL technology with delta-sigma fractional feedback division for precise frequency generation.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Evaluate alternative devices based on matching output frequency ranges, supply voltage compatibility, and package dimensions.

FAQ

How many factory-programmed configurations does the IDT8T49N105I support?

The device supports two factory-programmed default power-up configurations stored in One-Time Programmable (OTP) memory. These can be selected via the CONFIG pin or overwritten via the I2C interface.

What is the maximum output frequency supported by the IDT8T49N105I?

The device can generate any output frequency in the 0.98MHz to 312.5MHz range. Most output frequencies are supported up to a maximum of 1,300MHz, depending on the output divider setting.

Can the IDT8T49N105I track spread-spectrum clock modulation?

Yes, in the High-Bandwidth Frequency Translator mode, the device has a high PLL loop bandwidth designed to track input reference changes, such as Spread-Spectrum Clock modulation, without significantly attenuating jitter.