LTC6603CUF#PBF

Overview

The LTC6603CUF#PBF is a dual, matched, programmable lowpass filter designed for communications receivers and transmitters. It operates from a single supply voltage ranging from 2.7V to 3.6V on analog and digital rails, with an input supply up to 5.5V. The device features a 9th-order linear phase response and supports programmable bandwidths up to 2.5MHz. Filter gain can be set to 0dB, 6dB, 12dB, or 24dB via pin programming or SPI interface. Cutoff frequency accuracy is guaranteed within ±3.5% using an external resistor. The component is housed in a 24-lead, 4mm × 4mm QFN package.

Feature Summary

• Dual matched channels with 1.5° phase matching suitable for I/Q applications
• Differential rail-to-rail inputs and outputs for simple system interfacing
• Programmable cutoff frequency over six octaves using a single external resistor
• Low power shutdown mode accessible through the serial interface

Applications

• Small and low cost basestations including IDEN, PHS, TD-SCDMA, CDMA2000, WCDMA, and UMTS
• Low cost repeaters, radio links, and modems
• 802.11x receivers
• JTRS systems

Procurement Notes

Verify the specific suffix #PBF indicates lead-free finish and tube packaging when sourcing. Confirm the 'C' grade designation corresponds to the specified temperature range of 0°C to 70°C for your application requirements. Ensure the ordering information matches the exact part number to avoid functional discrepancies related to temperature grades or packaging types.

Selection Notes

Select this component when precise phase matching between two filter channels is required for quadrature signal processing. The internal oscillator simplifies design by removing the need for an external clock source, though an external clock input is available. Verify that the RBIAS resistor value falls within the 30.9kΩ to 200kΩ range to maintain accurate cutoff frequency specifications.

Part Context

This part belongs to the LTC6603 family of dual programmable lowpass filters. The 'CUF' designation identifies the commercial temperature grade variant packaged in a 24-lead QFN. Other variants include the 'IUF' for industrial temperature ranges. The device integrates matched filter networks and control logic into a compact form factor.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.