8th-Order, Lowpass, Elliptic, Switched-Capacitor Filters

The MAX7400/MAX7403/MAX7404/MAX7407 8th-order, lowpass, elliptic, switched-capacitor filters (SCFs) operate from a single +5V (MAX7400/MAX7403) or +3V (MAX7404/MAX7407) supply. These devices draw 2mA of supply current and allow corner frequencies from 1Hz to 10kHz, making them ideal for low-power anti-aliasing and post-DAC filtering applications. They feature a shutdown mode that reduces the supply current to 0.2µA.

Two clocking options are available: self-clocking (through the use of an external capacitor) or external clocking for tighter cutoff-frequency control. In addition, an offset adjustment pin (OS) allows for the adjustment of the DC output level.

The MAX7400/MAX7404 provide 82dB of stopband rejection and a sharp rolloff with a transition ratio of 1.5. The MAX7403/MAX7407 provide a sharper rolloff with a transition ratio of 1.2, while still delivering 60dB of stopband rejection. The fixed response of these devices simplifies the design task to corner-frequency selection by setting a clock frequency. The MAX7400/MAX7403/MAX7404/MAX7407 are available in 8-pin SO and DIP packages.

Applications

* ADC Anti-Aliasing * Air-Bag Electronics * CT2 Base Stations * Post-DAC Filtering * Speech Processing

* 8th-Order Lowpass Elliptic Filter

* Low Noise and Distortion -82dB THD + Noise (MAX7400)

* Clock-Tunable Corner Frequency (1Hz to 10kHz)

* 100:1 Clock-to-Corner Ratio

* Single-Supply Operation

* +5V (MAX7400/MAX7403)

* +3V (MAX7404/MAX7407)

* Low Power

* 2mA (Operating Mode)

* 0.2µA (Shutdown Mode)

* Available in 8-Pin SO and DIP Packages

* Low Output Offset: ±5mV