MAX261BCWG

Overview

The MAX261BCWG is a microprocessor-programmable universal active filter manufactured by Analog Devices Inc./Maxim Integrated. It features two second-order switched-capacitor sections housed in a 24-pin Wide SO package. The device supports center frequencies up to 57kHz and operates with single +5V or ±5V supplies. Key electrical parameters include a typical power supply current of 20mA at ±5V, a gain bandwidth product of 2.5MHz, and a slew rate of 6V/µs. It provides 64-step center frequency control and 128-step Q control via a digital interface.

Feature Summary

• Microprocessor-controlled programming for independent center frequency and Q adjustment
• Dual second-order switched-capacitor filter sections with universal configuration capabilities
• Internal oscillator support using crystal, RC network, or external clock generator

Applications

• Microprocessor-tuned filters
• Anti-aliasing filters
• Digital signal processing systems
• Adaptive filters
• Phase-locked loops

Procurement Notes

Verify the specific suffix BCWG corresponds to the commercial temperature range (0°C to +70°C) and Wide SO package as documented in the ordering information. Confirm that the component meets the required accuracy grade for the intended application, noting that B-grade devices have a guaranteed clock-to-f0 ratio error of 2%. Ensure compatibility with existing PCB footprints for the 24-pin wide small outline package.

Selection Notes

Select the MAX261BCWG when center frequencies up to 57kHz are required, distinguishing it from the MAX260 which has lower bandwidth but superior DC specifications. Choose this part over the MAX262 if operation below 140kHz is sufficient and higher clock-to-f0 ratios are preferred for better continuous filter approximation. Verify that the system can provide the necessary clock frequencies and digital interface signals for programming.

Part Context

The MAX261 is part of the MAX260/MAX261/MAX262 family of microprocessor-programmable universal active filters. This series allows for precise filter function realization without external components. The MAX261 specifically bridges the gap between the low-frequency, high-DC-accuracy MAX260 and the high-frequency MAX262, offering a center frequency range extending to 57kHz.

Replacement Considerations

Direct substitutes within the same package and pinout include the MAX260BCWG and MAX262BCWG, though their frequency ranges and DC characteristics differ. Other Maxim integrated filters such as the MAX263 or MAX264 offer similar functionality but may require different programming approaches or lack the microprocessor interface.