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Details, datasheet, quote on part number:74HC/HCT161
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| Part: | 74HC/HCT161 |
| Category: | Logic => Counters => Synchronous Counters-> CMOS/BiCMOS->HC/HCT Family |
| Description: | Presettable Synchronous 4-bit Binary Counter; Asynchronous Reset |
| Company: | Philips Semiconductors |
| Datasheet: | Download 74HC/HCT161 datasheet File size : 82 kB |
| Request For quote: | Find where to buy 74HC/HCT161
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Datasheet text preview:
INTEGRATED CIRCUITS
DATA SHEET
For a complete data sheet, please also download:
· The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications · The IC06 74HC/HCT/HCU/HCMOS Logic Package Information · The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
74HC/HCT161 Presettable synchronous 4-bit binary counter; asynchronous reset
Product specification File under Integrated Circuits, IC06 December 1990
Philips Semiconductors
Product specification
Presettable synchronous 4-bit binary counter; asynchronous reset
FEATURES · Synchronous counting and loading · Two count enable inputs for n-bit cascading · Positive-edge triggered clock · Asynchronous reset · Output capability: standard · ICC category: MSI GENERAL DESCRIPTION The 74HC/HCT161 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A. The 74HC/HCT161 are synchronous presettable binary counters which feature 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 (CP). The outputs (Q0 to Q3) of the counters may be preset to a HIGH or LOW level. A LOW level at the parallel enable
74HC/HCT161
input (PE) disables the counting action and causes the data at the data inputs (D0 to D3) to be loaded into the counter on the positive-going edge of the clock (providing that the set-up and hold time requirements for PE are met). Preset takes place regardless of the levels at count enable inputs (CEP and CET). A LOW level at the master reset input (MR) sets all four outputs of the flip-flops (Q0 to Q3) to LOW level regardless of the levels at CP, PE, CET and CEP inputs (thus providing an asynchronous clear function). The look-ahead carry simplifies serial cascading of the counters. Both count enable inputs (CEP and CET) must be HIGH to count. The CET input is fed forward to enable the terminal count output (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 the CP to TC propagation delay and CEP to CP set-up time, according to the following formula: 1 fmax = -------------------------------------------------------------------------------------------------t P (max) (CP to TC) + t S U (CEP to CP)
QUICK REFERENCE DATA GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns TYPICAL SYMBOL PARAMETER tPHL/ tPLH propagation delay CP to Qn CP to TC MR to Qn MR to TC CET to TC maximum clock frequency input capacitance power dissipation capacitance per package notes 1 and 2 CONDITIONS HC CL = 15 pF; VCC = 5 V 19 21 20 20 10 44 3.5 33 HCT 20 24 25 26 14 45 3.5 35 ns ns ns ns ns MHz pF pF UNIT Notes 1. CPD is used to determine the dynamic power dissipation (PD in µW): PD = CPD × VCC2 × fi + (CL × VCC2 × fo) where: fi = input frequency in MHz fo = output frequency in MHz (CL × VCC2 × fo) = sum of outputs CL = output load capacitance in pF VCC = supply voltage in V 2. For HC the condition is VI = GND to VCC For HCT the condition is VI = GND to VCC - 1.5 V
fmax CI CPD
December 1990
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Philips Semiconductors
Product specification
Presettable synchronous 4-bit binary counter; asynchronous reset
ORDERING INFORMATION See "74HC/HCT/HCU/HCMOS Logic Package Information". PIN DESCRIPTION PIN NO. 1 2 3, 4, 5, 6 7 8 9 10 14, 13, 12, 11 15 16 SYMBOL MR CP D0 to D3 CEP GND PE CET Q0 to Q3 TC VCC NAME AND FUNCTION asynchronous master reset (active LOW) clock input (LOW-to-HIGH, edge-triggered) data inputs count enable input ground (0 V) parallel enable input (active LOW) count enable carry input flip-flop outputs terminal count output positive supply voltage
74HC/HCT161
Fig.1 Pin configuration.
Fig.2 Logic symbol.
Fig.3 IEC logic symbol.
December 1990
3
Philips Semiconductors
Product specification
Presettable synchronous 4-bit binary counter; asynchronous reset
74HC/HCT161
Fig.4 Functional diagram.
FUNCTION TABLE INPUTS OPERATING MODE MR reset (clear) parallel load count hold (do nothing) Note 1. The TC output is HIGH when CET is HIGH and the counter is at terminal count (HHHH). H = HIGH voltage level h = HIGH voltage level one set-up time prior to the LOW-to-HIGH CP transition L = LOW voltage level I = LOW voltage level one set-up time prior to the LOW-to-HIGH CP transition q = lower case letters indicate the state of the referenced output one set-up time prior to the LOW-to-HIGH CP transition X = don't care = LOW-to-HIGH CP transition L H H H H H X X X CP X X X h I X CEP X X X h X I CET X I I h h h PE X I h X X X Dn L L H count qn qn Qn L L
(1) (1) (1)
OUTPUTS TC
L
December 1990
4
Philips Semiconductors
Product specification
Presettable synchronous 4-bit binary counter; asynchronous reset
74HC/HCT161
Fig.5 State diagram.
Fig.6
Typical timing sequence: reset outputs to zero; preset to binary twelve; count to thirteen, fourteen, fifteen, zero, one and two; inhibit.
December 1990
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