LTC1569IS8-7

Overview

The Analog Devices LTC1569IS8-7 is a 10th-order linear phase lowpass filter housed in an 8-lead SOIC package. It features a root raised cosine amplitude response and operates from single 3V to dual ±5V supplies. The cutoff frequency is programmable via a single external resistor or an external clock, with internal dividers of 1, 4, or 16 allowing seven octaves of tuning. Key electrical specifications include a maximum DC offset of 5mV, 80dB common-mode rejection ratio at DC, and 80dB signal-to-noise ratio at 5V supply. The device supports differential or single-ended inputs and includes power-saving modes.

Feature Summary

• Linear phase response combined with root raised cosine amplitude characteristics for optimal pulse shaping.
• Cutoff frequency set by one external resistor or external clock using internal dividers of 1, 4, or 16.
• High DC accuracy with a maximum output DC offset of 5mV.
• Supports both differential and single-ended input configurations.

Applications

• Data communication filters for 3V operation
• Linear phase and phase matched filters for I/Q signal processing
• Pin programmable cutoff frequency lowpass filters

Procurement Notes

Verify the specific suffix 'I' indicates the industrial temperature range (-40°C to 85°C) compared to the commercial grade. Confirm the 'S8' designation matches the required 8-lead plastic small outline package dimensions. Ensure the component source provides valid traceability documentation as this is a specialized analog filter IC.

Selection Notes

Select the LTC1569IS8-7 when a high-order linear phase response is required for data acquisition or communications. Use this part if the design necessitates a cutoff frequency tunable over seven octaves using only a single resistor. Consider the -40°C to 85°C operating range defined by the 'I' suffix for industrial environments.

Part Context

This component belongs to the LTC1569 family of sampled data filters. It is distinct from other members like the LTC1569CS8-7 by its extended temperature rating. The series is characterized by its ability to function without an external clock while maintaining precise frequency control through internal oscillators driven by external resistors.

Replacement Considerations

LTC1569CS8-7#PBF

FAQ

How is the cutoff frequency determined?

The cutoff frequency is set by a single external resistor connected between Pin 6 (RX) and Pin 7 (V+). Alternatively, it can be controlled by an external clock signal applied to Pin 5 (DIV/CLK).

What are the power supply options?

The device operates from single supplies ranging from 3V to 5V, or dual supplies up to ±5V. The total supply voltage must not exceed 11V.

Does the filter require an external clock?

No, the LTC1569-7 features an internal oscillator that sets the cutoff frequency using a single external resistor. An external clock is optional.