XR-558
XR-558 is Quad Timing Circuits manufactured by Exar.
DESCRIPTION
The XR-558 and the XR-559 quad timing circuits contain four independent timer sections on a single monolithic chip. Each of the timer sections on the chip are entirely independent, and each one can produce a time delay from microseconds to minutes, as set by an external R-C network. Each timer has its separate trigger terminal, but all four timers in the IC package share a mon reset control.
Both the XR-558 and the XR-559 quad timer circuits are "edge-triggered" devices, so that each timer section can be cascaded, or connected in tandem, with other timer sections, without requiring coupling capacitors.
The XR-558 is designed with open-collector outputs; each output can sink up to 100 m A. The XR-559 is designed with emitter-follower outputs. Each output can source up to 100 m A of load current. The outputs are normally at "low" state, and go to "high" state during the timing interval.
FEATURES
Four Independent Timer Sections High...
