LTC1069-1IN8#PBF

Overview

The LTC1069-1IN8#PBF is a monolithic 8th order progressive elliptic lowpass filter in an 8-lead plastic DIP package. It features a clock-tunable cutoff frequency defined as fCLK divided by 100, with a maximum of 12kHz using ±5V supplies or 8kHz on a single 5V supply. The device operates from single 3.3V to ±5V power rails, drawing 2mA at 3.3V and 3.8mA at ±5V. Electrical performance includes a typical passband ripple of ±0.15dB up to 0.9fCUTOFF, stopband attenuation reaching 70dB at 2fCUTOFF, and a wideband noise of 110μV RMS.

Feature Summary

• Monolithic 8th order elliptic filter topology
• Clock-tunable cutoff frequency capability
• Wide dynamic range with low wideband noise
• Single 3.3V to dual ±5V supply operation

Applications

• Telecommunication filters
• Antialiasing filters

Procurement Notes

Verify the ordering suffix #PBF indicates lead-free finish and standard tube packaging. Confirm the IN8 designation corresponds to the industrial temperature range of –40°C to 85°C and the 8-lead PDIP package type. Ensure compatibility with the required clock signal levels for the specific supply voltage configuration.

Selection Notes

Select this component when an 8th order elliptic response is required with precise clock-defined cutoff frequencies. Consider the 100:1 clock-to-cutoff ratio for timing constraints. Evaluate the 110μV RMS wideband noise against system sensitivity requirements. Verify that the available clock source meets the TTL/CMOS threshold specifications for the chosen supply voltage.

Part Context

This part belongs to the LTC1069 family of switch-capacitor filters. It shares the core 8th order elliptic architecture with variants like the LTC1069-6 but offers broader supply flexibility including 3.3V operation. The IN8 variant specifically targets industrial environments requiring extended temperature stability compared to commercial grade parts.

Replacement Considerations

LTC1069-1CN8#PBF (Commercial Grade)

FAQ

How is the cutoff frequency determined?

The cutoff frequency equals the external clock frequency divided by 100.

What is the maximum clock frequency allowed?

The maximum clock frequency is 1.2MHz with ±5V supplies, 0.8MHz with a single 5V supply, and 0.5MHz with a single 3.3V supply.

Can the device operate with a single 3.3V supply?

Yes, it supports single 3.3V operation with a maximum cutoff frequency of 5kHz and a supply current of 2mA.