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74LVC161: Presettable synchronous 4-bit binary counter; asynchronous reset (Based on PIP 74LVC161)

The 74LVC161 is a synchronous presettable binary counter which features an internal look-ahead carry and can be used for high-speed counting. Synchronous operation is provided by having all flip-flops clocked simultaneously on the positive-going edge of the clock (pin CP). The outputs (pins Q0 to Q3) of the counters may be preset to a HIGH-level or LOW-level. A LOW-level at the parallel enable input (pin PE) disables the counting action and causes the data at the data inputs (pins D0 to D3) to be loaded into the counter on the positive-going edge of the clock (provided that the set-up and hold time requirements for PE are met). Preset takes place regardless of the levels at count enable inputs (pins CEP and CET). A LOW-level at the master reset input (pin MR) sets all four outputs of the flip-flops (pins Q0 to Q3) to LOW-level regardless of the levels at input pins CP, PE, CET and CEP (thus providing an asynchronous clear function).

The look-ahead carry simplifies serial cascading of the counters. Both count enable inputs (pin CEP and CET) must be HIGH to count. The CET input is fed forward to enable the terminal count output (pin TC). The TC output thus enabled will produce a HIGH output pulse of a duration approximately equal to a HIGH-level output of Q0. This pulse can be used to enable the next cascaded stage.

The maximum clock frequency for the cascaded counters is determined by tPHL (propagation delay CP to TC) and tsu (set-up time CEP to CP) according to the formula: fmax = 1/ (tPHL(max)+tsu)

It is a high-performance, low-power, low-voltage, Si-gate CMOS device and superior to most advanced CMOS compatible TTL families.

74LVC161: Product Block Diagram

Outline 3d SOT338-1

Data Sheets (1)

Application Notes (5)

Brochures (1)

Selector Guides (2)

Package Information (4)

Packing (3)

Supporting Information (4)

IBIS Model

• lvc161 IBIS model (REV 1.0) ibs LVC161 4/7/2013

SPICE model

• lvc Spice model (REV 1.0) ZIP LVC 5/7/2013

Ordering Information

Package Information

Product ID	Package Description	Outline Version	Reflow/Wave Soldering	Packing	Product Status	Part NumberOrdering code(12NC)	Marking	Chemical Content	RoHS / Pb Free / RHF	LeadFree Conversion Date	EFR	IFR(FIT)	MTBF(hour)	MSL	MSL LF
74LVC161BQ		SOT763-1		Reel 7" Q1/T1	Active	74LVC161BQ,115 (9352 756 12115)	LVC161	74LVC161BQ		Always Pb-free	123.8	3.87	2.58E8	1	1
74LVC161D		SOT109-1	SO-SOJ-REFLOW SO-SOJ-WAVE SO-SOJ-REFLOW SO-SOJ-WAVE	Reel 13" Q1/T1	Active	74LVC161D,118 (9352 105 10118)	74LVC161D	74LVC161D		Always Pb-free	123.8	3.87	2.58E8	1	1
				Bulk Pack	Active	74LVC161D,112 (9352 105 10112)	74LVC161D	74LVC161D		Always Pb-free	123.8	3.87	2.58E8	1	1
74LVC161DB		SOT338-1	SSOP-TSSOP-VSO-REFLOW SSOP-TSSOP-VSO-WAVE SSOP-TSSOP-VSO-REFLOW SSOP-TSSOP-VSO-WAVE	Reel 13" Q1/T1	Active	74LVC161DB,118 (9352 105 20118)	LVC161	74LVC161DB		week 13, 2005	123.8	3.87	2.58E8	1	1
				Bulk Pack	Active	74LVC161DB,112 (9352 105 20112)	LVC161	74LVC161DB		week 13, 2005	123.8	3.87	2.58E8	1	1
74LVC161PW		SOT403-1	SSOP-TSSOP-VSO-WAVE	Reel 13" Q1/T1	Active	74LVC161PW,118 (9352 105 30118)	LVC161	74LVC161PW		week 10, 2005	123.8	3.87	2.58E8	1	1
				Bulk Pack	Active	74LVC161PW,112 (9352 105 30112)	LVC161	74LVC161PW		week 10, 2005	123.8	3.87	2.58E8	1	1