DESCRIPTION
The LTC®1068 product family consists of four monolithic clock-tunable filter building blocks. Each product contains four matched, low noise, high accuracy 2nd order switched-capacitor filter sections. An external clock tunes the center frequency of each 2nd order filter section. The LTC1068 products differ only in their clock-to-center frequency ratio. The clock-to-center frequency ratio is set to 200:1 (LTC1068-200), 100:1 (LTC1068), 50:1 (LTC1068-50) or 25:1 (LTC1068-25). External resistors can modify the clock-to-center frequency ratio. High performance, quad 2nd order, dual 4th order or 8th order filters can be designed with an LTC1068 family product. Designing filters with an LTC1068 product is fully supported by FilterCAD™ filter design software for Windows.

FEATURES
■ Four Identical 2nd Order Filter Sections in an SSOP Package
■ 2nd Order Section Center Frequency Error: ±0.3% Typical and ±0.8% Maximum
■ Low Noise per 2nd Order Section, Q ≤ 5:
   LTC1068-200 50µVRMS, LTC1068 50µVRMS
   LTC1068-50 75µVRMS, LTC1068-25 90µVRMS
■ Low Power Supply Current: 4.5mA, Single 5V, LTC1068-50
■ Operation with ±5V Power Supply, Single 5V Supply or Single 3.3V Supply

APPLICATIONS
■ Lowpass or Highpass Filters:
   LTC1068-200, 0.5Hz to 25kHz; LTC1068, 1Hz to
   50kHz; LTC1068-50, 2Hz to 50kHz; LTC1068-25,
   4Hz to 200kHz
■ Bandpass or Bandreject (Notch) Filters:
   LTC1068-200, 0.5Hz to 15kHz; LTC1068, 1Hz to
   30kHz; LTC1068-50, 2Hz to 30kHz; LTC1068-25,
   4Hz to 140kHz