IW4541B

TECHNICAL DATA IW4541B Programmable Timer High-Performance Silicon-Gate CMOS The IW4541B programmable timer consists of a 16-stage binary counter, an oscillator that is controlled by external R-C components (2 resistors and a capacitor), an automatic power-on reset circuit, and output control logic. The counter increments on positive-edge clock transitons and can also be reset via the MASTER RESET input. The output from this timer is the Q or not 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” ORDERING INFORMATION and after a MASTER RESET is initiated, the output (assuming Q output IW4541BN Plastic has been selected) changes from a low to a high state after 2N-1 counts and IW4541BD SOIC remains in that state until another MASTER RESET pulse is applied or TA = -55° to 125° C for all packages the MODE input is set to a logic “1”. Timing is initialized by setting the AUTO RESET input (pin 5) to logic “0”and turning power on. If pin 5 is set to logic “1”, the AUTO RESET circuit is disabled and counting will not start untill after a positive MASTER RESET pulse is applied and returns to a low level. The AUTO RESET consumes an appreciable amoun...