By Michael A. Wyatt, May 30, 1994
Most op amps have a low output impedance at frequencies well below their closed-loop bandwidth, but as frequency increases, so does the output impedance. When the op amp is used in a Sallen-Key low-pass filter, this increase in output impedance
By Michael A. Wyatt, January 23, 1992
This simple circuit automatically chooses between an external clock, if present, or an internal clock if not. The circuit, which requires no selector switch, has proven useful in laboraty test equipment.
By Michael A. Wyatt, January 31, 1991
Four shift registers and four DIP switches form the basis of a simple 32-bit pattern generator that can operate at over 10 Mbits/s.