Abstract: A low pass filter includes a switchable resistor bank, a gain stage, and a capacitor bank. The resistors and capacitors switched into the circuit determine a cutoff frequency of the low pass filter. Frequency programmability may be obtained using the switchable resistor bank implemented as a parallel bank of binary weighted resistors. Further frequency programmability may be obtained using the switchable capacitor bank in conjunction with the switchable resistor bank. The resistor and capacitor processes in a semiconductor wafer are sufficiently accurate and repeatable so as to minimize any necessary calibration.

Abstract: A low pass filter includes a switchable resistor bank, a gain stage, and a capacitor bank. The resistors and capacitors switched into the circuit determine the cutoff frequency of the low pass filter. The frequency programmability may be obtained using the switchable resistor bank and may be implemented as a parallel bank of binary weighted resistors. Further programmability may be obtained using the switchable capacitor bank in conjunction with the switchable resistor bank. The resistor and capacitor processes in a semiconductor wafer are sufficiently accurate and repeatable so as to minimize any necessary calibration.