LTC1067CS#TRPBF

Overview

The LTC1067CS#TRPBF is a dual, rail-to-rail, very low noise universal switched-capacitor building block. It integrates two identical second-order filter sections capable of realizing bandpass, highpass, lowpass, notch, and allpass functions using three to five external resistors. The center frequency is tuned by an external clock with a nominal 100:1 ratio for the LTC1067 variant. It operates from a single 3V supply or dual supplies up to ±5V, consuming approximately 4.5mA at 250kHz. The device provides over 80dB dynamic range on a 3.3V supply with less than 40mVRMS noise for Q ≤ 5.

Feature Summary

• Dual second-order switched-capacitor filter sections in a single package
• Rail-to-rail input and output operation for wide dynamic range
• Low power consumption suitable for battery-operated applications
• Programmable center frequency via external clock signal

Applications

• Notch filters for interference rejection
• Narrowband bandpass filters for tone detection
• Noise reduction systems requiring precise filtering

Procurement Notes

Verify the specific suffix #TRPBF indicates tape and reel packaging when sourcing. Confirm the 'C' grade corresponds to the commercial temperature range of 0°C to 70°C. Ensure the clock source meets the specified logic level thresholds for the chosen supply voltage to prevent improper switching behavior.

Selection Notes

Select this component when a dual filter solution is required within a limited footprint. The LTC1067-50 variant offers lower power consumption if current efficiency is prioritized over maximum clock speed. Verify that the required center frequency range falls within the 0.001 to 20 kHz limit for optimal performance.

Part Context

This part belongs to the LTC1067 family of universal switched-capacitor filters. It serves as a building block for higher-order filter designs. The CS designation identifies the plastic SOIC-16 package variant. It complements other Linear Technology analog signal processing components.

Replacement Considerations

The LTC1067-50 is a lower-power alternative within the same family. Mask programmable versions are available for custom clock-to-cutoff ratios in an SO-8 package. Direct pin-compatible replacements require matching the 16-lead SSOP/SO form factor and switched-capacitor architecture.

FAQ

What is the internal clock-to-center frequency ratio?

The LTC1067 has a fixed internal clock-to-center frequency ratio of 100:1.

How is the clock feedthrough minimized?

Clock feedthrough can be reduced by adding a simple RC lowpass network at the final filter output and ensuring proper PCB layout with isolated analog ground planes.

Can the device operate with a single supply?

Yes, the device operates from a single 3V supply or dual supplies up to ±5V, with rail-to-rail input and output capabilities.