View s8081bf-s datasheet:

S8081BF-S (1/2) IL08 C-MOS CR TIMER —TOP VIEW— 7 CR 1 GND VDD 8 6 DISCHARGE 5 3 TRIGGER OUT SET 2 7 CR 2 SET 4 RESET OUT 3 6 DISCHARGE RESET 4 5 TRIGGER 7 OUTPUT CR FF20 3 20-STAGE TOUT CONTROL OSC LEVEL OUT 6 DISCHARGE DIVIDER SELECT LOGIC SHIFTER INPUT 5 TRIGGER CHATTERING KILLER 2 INPUT SET CIRCUIT 4 INPUT RESET CIRCUIT POWER-ON VOLTAGE CLEAR REGULATOR CIRCUIT S8081BF-S (2/2) 1) TRIGGER OPERATION TRIGGER OUT TOUT TOUT RESET 2) SET OPERATION SET OUT TOUT TOUT RESET TOUT = TOSC x 219 TOSC = 1.45 x RT x CT