LTC1065CN8#PBF

Overview

The LTC1065CN8#PBF is a monolithic, clock-tunable, linear phase 5th order Bessel lowpass filter with DC accuracy. It operates from ±2.375V to ±8V power supplies and features a typical output DC offset of 1mV. The cutoff frequency is controlled by an internal or external clock with a fixed 100:1 ratio. Key electrical parameters include a maximum cutoff frequency of 50kHz, wideband noise of 80µVRMS, and clock feedthrough of 50µVRMS. The device provides 80dB common mode rejection and maintains low distortion (0.004% THD at 2VRMS). It is housed in an 8-pin PDIP package.

Feature Summary

• Clock-tunable cutoff frequency using internal RC oscillator or external clock source
• Linear phase response approximating a 5th order Bessel polynomial
• High DC accuracy with typically 1mV output offset voltage
• Low clock feedthrough and wideband noise for precision signal conditioning

Applications

• Audio processing systems requiring linear phase characteristics
• Strain gauge amplifier signal conditioning
• Anti-aliasing filters for data acquisition systems
• Digital voltmeters and low-level filtering applications
• Smoothing and reconstruction filters in digital-to-analog conversion

Procurement Notes

Verify the specific suffix CN8 corresponds to the commercial temperature range (0°C to 70°C) and 8-pin DIP package configuration. Confirm lead-free compliance via the PBF designation. Cross-reference the manufacturer part number with official Analog Devices documentation to ensure compatibility with design specifications before procurement.

Selection Notes

Select this component when a precise Bessel response is required without external passive components. Ensure the application supports dual supply voltages between ±2.375V and ±8V. Consider the 100:1 clock-to-cutoff ratio when designing the clock generation circuitry. Verify that the input signal levels remain within the specified dynamic range to maintain low distortion performance.

Part Context

The LTC1065 belongs to a family of switch-capacitor filters designed for high-precision analog signal processing. It replaces traditional active RC filters by eliminating the need for external resistors and capacitors for the filter core. The CN8 variant specifically denotes the commercial grade version in an 8-pin plastic dual in-line package, suitable for general-purpose industrial and commercial applications.

Replacement Considerations

The LTC1063 offers a Butterworth response with pin compatibility. For higher-order filtering, consider the LTC1064 series. The LTC1164 provides lower power consumption but limited maximum clock frequency.