CTST571QG

Specialized ICS Overview

The CTST571 is a digitally programmable capacitor IC designed for tuning filters and crystal/SAW-based oscillators to a desired center frequency. It features a capacitance range of 6.6pF to 37.553pF with a minimum step size of 0.063pF. The device operates on a 2.5V to 5.0V supply voltage and includes an internal nonvolatile EEPROM for permanent data storage. It utilizes an 11-bit serial shift register for control word input, allowing real-time adjustment or factory-set programming.

Specialized ICS Feature Summary

• Capacitive tuning range from 6.6pF to 37.553pF
• Minimum capacitance step size of 0.063pF
• Nonvolatile EEPROM memory for permanent control word storage
• Serial interface via DA and CLK pins for programming

Specialized ICS Applications

• Oscillator tuning
• Tunable filter banks
• Crystal oscillator calibration

Specialized ICS Procurement Notes

Verify the specific package variant required, as the CTST571 is available in both SON8 (CTST571QG) and MLP6 (CTST571MG) configurations. Confirm that the manufacturing environment supports the necessary programming voltage requirements, specifically the PV pin operation up to 6.1V during EEPROM write cycles. Ensure compatibility with the 11-bit serial control word protocol before integration.

Specialized ICS Selection Notes

Select the CTST571 when precise digital capacitance adjustment is needed for RF applications. The SON8 package offers a small form factor suitable for space-constrained designs. Consider parallel usage of multiple devices if higher total capacitance values are required beyond the single-device maximum of 37.553pF. Verify temperature stability requirements against the specified ppm/°C variations.

Specialized ICS Part Context

The CTST571 belongs to CTS-Frequency Controls' specialized integrated circuit lineup focused on frequency control solutions. It serves as a direct replacement for discrete variable capacitor networks in production environments, reducing labor costs associated with manual trimming. The device is part of a family including similar programmable tuning components.

Specialized ICS Replacement Considerations

Publicly confirmed substitute part numbers are not provided in the source documentation. Designers should verify pinout compatibility and electrical characteristics carefully when considering alternative programmable capacitors from other manufacturers.