LTC1068-25IG

Overview

The LTC1068-25IG is a clock-tunable, quad second-order switched-capacitor filter building block from Analog Devices. It integrates four matched, low-noise sections within a 28-lead SSOP package. The device features an internal clock-to-center frequency ratio of 25:1. It operates on supply voltages ranging from 3.14V to ±5.5V and supports industrial temperature ranges from -40°C to +85°C. Key electrical parameters include a typical power supply current of 6.5mA at 4.75V, a GBW product of 6MHz, and a slew rate of 10V/µs. The center frequency error is typically ±0.3% with a maximum of ±0.8%.

Feature Summary

• Contains four identical second-order filter sections in a single surface mount package.
• Clock-tunable architecture allows external adjustment of the center frequency via an external clock source.
• Supports multiple operating modes including Mode 1 for notch filters and Mode 3 for state-variable configurations.
• Low noise performance optimized for Q factors up to 5.

Applications

• Dual matched fourth-order Butterworth lowpass filters
• High-speed eighth-order linear phase bandpass filters
• Tunable instrumentation signal conditioning

Procurement Notes

Verify the specific suffix 'IG' confirms the industrial temperature range (-40°C to +85°C) and lead-free finish. Confirm the package type matches the required 28-lead SSOP footprint. Ensure the design utilizes the correct clock-to-center frequency ratio of 25:1 for the intended application bandwidth.

Selection Notes

Select this component when a fixed 25:1 clock-to-center frequency ratio is required. Compare against LTC1068 (100:1), LTC1068-50 (50:1), and LTC1068-200 (200:1) if different tuning ratios are needed. Consider the noise specifications relative to the target Q factor and supply voltage configuration.

Part Context

This part belongs to the LTC1068 family of universal switched-capacitor filters. The family members differ primarily by their nominal clock-to-center frequency ratios. The IG suffix denotes the industrial temperature grade variant housed in a standard plastic SSOP package.

Replacement Considerations

LTC1068-25CG#PBF serves as the commercial temperature version of this component. Other family members like LTC1068-25IG#TRPBF offer tape and reel packaging options instead of tube packaging.