M74HC161 SYNCHRONOUS PRESETTABLE 4-BIT COUNTER HIGH SPEED : f = 62 MHz (TYP.) at V = 6V MAX CC LOW POWER DISSIPATION: I =4A(MAX.) at T =25C CC A HIGH NOISE IMMUNITY: V = V = 28 % V (MIN.) NIH NIL CC DIP SOP TSSOP SYMMETRICAL OUTPUT IMPEDANCE: I = I = 4mA (MIN) OH OL BALANCED PROPAGATION DELAYS: t t PLH PHL ORDER CODES WIDE OPERATING VOLTAGE RANGE: PACKAGE TUBE T & R V (OPR) = 2V to 6V CC DIP M74HC161B1R PIN AND FUNCTION COMPATIBLE WITH SOP M74HC161M1R M74HC161RM13TR 74 SERIES 161 TSSOP M74HC161TTR DESCRIPTION The M74HC161 is an high speed CMOS Two enable inputs (TE and PE) and CARRY SYNCHRONOUS 4-BIT BINARY output are provided to enable easy cascading of PRESETTABLE COUNTER fabricated with silicon counters, which facilities easy implementation of 2 gate C MOS technology. N-bit counters without using external gates. The CLOCK input is active on the rising edge. All inputs are equipped with protection circuits Both LOAD and CLEAR inputs are active LOW. against static discharge and transient excess Presetting is synchronous on the rising edge of voltage. the clock, the function is cleared asynchronously. PIN CONNECTION AND IEC LOGIC SYMBOLS July 2001 1/12 Obsolete Product(s) - Obsolete Product(s)M74HC161 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION PIN No SYMBOL NAME AND FUNCTION Asynchronous Master 1 CLEAR Reset Clock Input (LOW to 2 CLOCK HIGH, Edge-triggered) 3, 4, 5, 6 A, B, C, D Data Inputs 7 PE Count Enable Input 10 TE Count Enable Carry Input 9LOAD Parallel Enable Input 14, 13, 12, QA to QD Flip Flop Outputs 11 15 CARRY Terminal Count Output 8 GND Ground (0V) 16 Vcc Positive Supply Voltage TRUTH TABLE INPUTS OUTPUTS FUNCTION CLEAR LOAD PE TE CLOCK QA QB QC QD L X X X X L L L L RESET TO0 H L X X A B C D PRESET DATA H H X L NO CHANGE NO COUNT H H L X NO CHANGE NO COUNT H H H H COUNT UP COUNT H X X X NO CHANGE NO COUNT X : Dont Care A, B, C, D : Logic level of data inputs Carry : CARRY = TEQ Q Q Q A B C D LOGIC DIAGRAM This logic diagram has not be used to estimate propagation delays 2/12 Obsolete Product(s) - Obsolete Product(s)