LTC1061ACN#PBF

Overview

The LTC1061ACN#PBF is a high-performance triple universal filter building block housed in a 20-lead plastic DIP package. It integrates three independent second-order filter sections capable of producing lowpass, bandpass, highpass, notch, and allpass functions using only two to five external resistors per section. The device operates from single or dual supplies ranging from 4.7V to 16V (or -2.37V to -8V). Center frequencies are clock-tunable, typically ranging from 0.1Hz to 35kHz depending on the Q factor and supply voltage. Key electrical specifications include a guaranteed signal-to-noise ratio of 90dB, a maximum clock frequency of 2.5MHz at -5V supplies, and a power supply current of approximately 6mA at -5V.

Feature Summary

• Integrates three universal filter building blocks within a single package for compact circuit design
• Supports multiple filter topologies including Butterworth, Chebyshev, and Elliptic responses through cascading
• Features clock-tunable center frequencies with internal ratios of 50:1 or 100:1 selectable via pin configuration
• Compatible with T2L and CMOS logic levels for clock input synchronization

Applications

• Tracking filters requiring precise center frequency adjustment
• Antialiasing filters for data acquisition systems
• High-order bandpass and lowpass filter implementations
• Notch filters for interference rejection

Procurement Notes

Verify that the component matches the specific ACN suffix for the 20-lead plastic DIP package and lead-free construction. Confirm the manufacturer designation as Analog Devices Inc. Ensure the datasheet revision aligns with the required operating temperature range of -40°C to +85°C. Cross-reference the part number against official distributor catalogs to confirm availability status and compliance with RoHS directives.

Selection Notes

Select this component when a design requires three synchronized filter sections sharing a common clock source. Consider the available modes of operation; Mode 1 offers higher speed for lower Q applications, while Mode 3 provides greater flexibility for higher Q designs. Evaluate the external resistor count and tolerance requirements, as filter accuracy depends heavily on these passive components. Ensure the system supply voltage supports the desired clock-to-center frequency ratio and input frequency range.

Part Context

The LTC1061 belongs to a family of switched-capacitor universal filters that includes the LTC1059 and LTC1060. While the LTC1059 contains one section and the LTC1060 contains two, the LTC1061 consolidates three sections into one package. This allows designers to construct complex higher-order filters without requiring multiple discrete ICs, simplifying board layout and reducing component count for applications like audio processing or instrumentation.

Replacement Considerations

The N20 package is noted as an alternate source option. Direct functional replacements within the same series include the LTC1059 and LTC1060, though these contain fewer filter sections and require different circuit topologies to achieve equivalent performance.