74161 Synchronous Presettable 4-Bit Binary Counter with Async. Clear

Pin Arrangement

CLK Rising Edge Trigger CEP Count Enable Parallel CET Count Enable Trickle RCO Ripple Carry Out CLR' Asynchronous Clear LD' Synchronous Load

Truth Table

Input					Output			Operation
CLR'	LD'	CLK	Enable		Q(t-1)	Q(t)	RCO
			CEP	CET	Q3 - Q0	Q3 - Q0
H	H		H	H	< 15	Q(t-1) + 1	L	Count Up
H	H		H	H	H H H L	H H H H	H	Count Up & Carry Out
L	X	-	X	X	-	L L L L	L	Asynchronous Clear
H	L		X	X	-	D3 - D0	-	Load Data
H	H	-	L	H	H H H H	H H H H	H	Hold but Carry Out
H	H	-	X	L	-	-	L	Hold

Cascade Connection

Electrical Characteristics

Propagation Delay

	Input	Output	N	LS	ALS	ALS 1000	F	S	AS	AS 1000	HC	HCT	Unit [max]
fmax	CLK	-	25	25	30	-	90	70	75	-	21	-	MHz(min)
tw	CLK		25	25	16.5	-	5	10	6.7	-	20	-	nS(min)
	CLR		20	20	15	-	5	13	8	-	20	-	nS(min)
tsu	data	-	20	20	15	-	5	8	8	-	38	-	nS(min)
	Enable		20	20	20	-	11.5	12	8	-	-	-	nS(min)
tenable	Load	-	25	20	-	-	11.5	16	-	-	34	-	nS(min)
thold	data	-	0	0	0	-	2	0	0	-	13	-	nS(min)
tpd	CET	RCO	16	14	13	-	8.5	10	9	-	49	-	nS(max)
	CLK	RCO	35	35	26	-	15	18	12.5	-	54	-	nS(max)
		Q3 - Q0	29	27	17	-	11	13	13	-	52	-	nS(max)
	CLR	Q3 - Q0	38	28	24	-	13	20	13	-	53	-	nS(max)
ICC	-		101	32	21	-	55	127	53	-	0.08	-	mA(max)




Input Characteristics

		N	LS	ALS	ALS 1000	F	S	AS	AS 1000	Unit
CLK	High	80	40	40	-	20	125	20	-	uA
	Low	3.2	0.8	0.2	-	0.6	5	0.5	-	mA
CET	High	80	40	40	-	20	100	40	-	uA
	Low	3.2	0.8	0.2	-	1.2	4	1	-	mA
LD'	High	40	40	40	-	20	75	60	-	uA
	Low	1.6	0.8	0.2	-	1.2	3	1.5	-	mA
Others	High	40	20	20	-	20	50	20	-	uA
	Low	1.6	0.4	0.2	-	0.6	2	0.5	-	mA




Output Characteristics

		N	LS	ALS	ALS 1000	F	S	AS	AS 1000	HC	HCT	Unit
All Outputs	High	0.8	0.4	0.4	-	1	1	2	-	4	-	mA
	Low	16	8	8	-	20	20	20	-	4	-	mA

Reference

74160 : Synchronous Presettable 4-bit BCD Counter with Async. Clear.
74161 : Synchronous Presettable 4-bit Binary Counter with Async. Clear.
74162 : Synchronous Presettable 4-bit BCD Counter with Synchronous Clear.
74163 : Synchronous Presettable 4-bit Binary Counter with Synchronous Clear.