The resistor programmable universal active filter is a CMOS chip that can be configured for Lowpass, Highpass, Elliptic, Notch or Allpass filters using external resistors. The filters come in one (8 pin) or two (16 pin) section versions. The device is a switched-capacitor filter using a topology that requires fewer pins and less power consumption than other switched-capacitor universal active filters. The clock to corner ratio as well as the Q are set by external resistors.

Depending on the filter type and response, from zero to nice external resistors are needed for each section. The sections may be cascaded to realize higher order filters.

The devices have a selectable nominal sample to corner ratio of either 50 to 1 or 100 to 1 and come in either a low power version (fo < 3kHz) or a higher power version (fo < 20 kHz). With device current as low as 50 ua per section, the chip is ideal for low power and portable application. The devices are double sampled to reduce the clock frequency by a factor or two.

• Low Power Consumption
• Low Voltage Operation
• Low Cost
• Input Multiplexor
• Adjustable Gain
• Small Package Size 8 or 16 DIP or SOIC 0.5 to over 200
• Wide Q Range
• Wide Clock to Center/Corner Frequency
• Range 25:1 to over 200:1
• Accurate Switched-Capacitor Technology

• General Purpose Filtering
• Portable Equipment
• Instrumentation