|MSHN1-6 - Selectable Highpass/Notch Filter|
The selectable highpass/notch filter IC Is a CMOS chip that can be configured for either a highpass or a notch filter. The highpass response can be an 8 pole Butterworth, a 7 pole Elliptic or an 8 pole Bessel filter. The notch response can be narrow, wide or deep.The device uses switched-capacitor filters and no external components (except for decoupling capacitors) are required, Only an external CMOS level clock is needed. An onchip lowpass filter is included to reduce output noise. The -3dB point is at approximately 0.2 of the clock frequency.
A four input multiplexor and externally selectable gain setting pin, along with a power down and clock to corner ratio select pin are included in the 16 pin version. An 8 pin version is also available for PC board area savings. Typical current consumption is as low as 200 uA and the minimum operating voltage is 2.7 volts, making the device ideal for portable applications. MSHN3, MSHN4 and MSHN6 are low current, lower frequency versions.