CD4541BM (TEXAS INSTRUMENTS)

The CD4541BM is a CMOS Programmable Timer consists of a 16-stage binary counter, an oscillator that is controlled by external R-C components, an automatic power-on reset circuit and output control logic. The counter increments on positive-edge clock transitions and can also be reset via the MASTER RESET input. The output from this timer is the Q or Q output from the 8th, 10th, 13th or 16th counter stage. The desired stage is chosen using time-select inputs A and B. The output is available in either of two modes selectable via the MODE input, pin 10. When this MODE input is a logic 1, the output will be a continuous square wave having a frequency equal to the oscillator frequency divided by 2N. With the MODE input set to logic 0 and after a MASTER RESET is initiated, the output (assuming Q output has been selected) changes from a low to a high state after 2N-1 counts and remains in that state until another MASTER RESET pulse is applied or the MODE input is set to a logic 1.