AC139 ACT139 54AC/74AC139 54ACT/74ACT139 Dual 1-of-4 Decoder/Demultiplexer Description Connection Diagrams The AC/ACT139 is a high-speed, dual 1-of-4 decoder/demultiplexer. The device has two independent decoders, each accepting two inputs [ ~ 6] Vec and providing four mutually-exclusive active-LOW - outputs. Each decoder has an active-LOW Enable Aoa [2 15] input which can be used as a data input fora AB] [74] Aco 4-output demultiplexer. Each half of the "AC/"ACT139 can be used as a function generator Oras fa] Ae providing all four minterms of two variables. 6: [5] [12] Bo. Ozal 6 11151, Multifunction Capability . B pale * Two Completely independent 1-of-4 Decoders Os [7] [19] Oz, * Active LOW Mutually Exclusive Outputs ano [8 19] Gap Outputs Source/Sink 24 mA "ACT139 has TTL-Compatible Inputs Pin Assignment . for DIP, Flatpak and SOIC Ordering Code: See Section 6 Oza Os NC Dos Ara @a@aes & Logic Symbol a, [3] [3] Aoa i {| dt ovo we E Ao A E Ao A: Nc [13] (yj ne Oe [12] faa ve: DECODER a DECODER b ix BB me Oo O1 O2 03 Oo 01 02 O23 (16) [17} te Ars Boo o d o O o o o og} el z oO Pin Assignment for LCC Pin Names Ao, A1 Address Inputs E Enable inputs Oo - Os Outputs 5-39AC139 ACT139 Logic Diagram Ea Ata E> Ach An: Ooa Ora Oza O22 Ocn O1n O2e Op Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays. Functional Description The AC/'ACT139 is a high-speed dual 1-of-4 decoder/demultiplexer. The device has two independent decoders, each of which accepts two binary weighted inputs (Ao - A1) and provides four mutually exclusive active-LOW outputs (Go - Os). Each decoder has an active-LOW enable (E). When E is HIGH all outputs are forced HIGH. The enable can be used as the data input for a 4-output demultiplexer application. Each half of the ACIACT139 generates ali four minterms of two variables. These four minterms are useful in some applications, replacing multiple gate functions as shown in Figure a, and thereby reducing the number of packages required in a logic network. Truth Table inputs Outputs Ao {| A1 | Oo | G1 | O2 | Os Crererl|m Irirx rmrirmrrex xrtiret Ziririre tiIritre Crigrs H=HIGH Voltage Level L=LOW Voltage Level X= Immaterial Figure a: Gate Functions (each half) E E Ao =p>- Oo Ao =D A At E Ee =D O1 Ao =>- 01 Al AY E A Ai E E = = AY AyAC139 ACT139 DC Characteristics (unless otherwise specified) Symbol Parameter 54AC/ACT 74ACIACT Units Conditions VIN = Vcc or Maximum Quiescent Ground, lec Supply Current 160 80 HA Veco =5.5 V, Ta = Worst Case Vin = Voc or Maximum Quiescent Ground, lec Supply Current 8.0 8.0 HA Vec =5.5 V, Ta = 25C : tgs VIN=Vec-2.1V Maximum Additional lect ; 1.6 1.5 mA Voc = 5.5 V, Icc/Input (ACT139) Ta =Worst Case AC Characteristics 74AC 54AC 74AC Ta= +25C Ta= 55C | Ta= 40C : Symbol Parameter Vec* CL= 50 oF to + 125C to +85C | Units | Fig. a) =e C.=50 pF | CL=50 pF No. Min Typ Max | Min Max | Min Max Propagation Delay 3.3 1.0 8.0 11.5 1.0 14.5 1.0 13.0 tPLH An to On 50} 140 65 85/10 1140/10 os | 8 | 36 Propagation Delay 3.3 1.0 7.0 10.0 1.0 12.5 1.0 11.0 trHe An to On 50/10 55 75|10 100|10 35} | 36 teLy Propagation Delay 3.3 1.0 9.5 12.0 1.0 14.5 1.0 13.0 ns 36 En to Gn 5.0] 1.0 7.0 8.5 1.0 11.0 1.0 10.0 Propagation Delay 3.3 1.0 8.0 10.0 1.0 12.5 1.0 11.0 . tPHL En to On 50/10 60 75]10 10] 10 #85] | 36 *Voltage Range 3.3 is 3.3 V+0.3 V Voltage Range 5.0 is 5.0 V+0.5 V Military parameters given herein are for general references only. For current military specifications and subgroup testing information please request Falrchilds Table | data sheet from your Fairchild sales engineer or account representative.AC139 ACT139 AC Characteristics T4ACT 54ACT 74ACT ; Tax 425C Ta= 55C | Ta= 40C Symbol Parameter Vee CL=80 pF to +125C | to +85C | Units | Fig. (V) =ouP CL=50 pF | CL=50 pF No. Min Typ Max | Min Max | Min Max teu Propagation Delay 50} 10 60 85|10 120/110 95] ns | 36 An to On tPHL Propagation Delay 50/10 60 95] 10 110] 10 105] ns | 36 An to On tL Propagation Delay 50 | 10 7.0 100| 10 125] 10 110] ns | 36 En to On tPHL Propagation Delay 50] 10 70 95|10 120] 10 105} ns | 36 En to On *Voltage Range 5.0 is 5.0 V+0.5 V Military parameters given herein are for general references only. For current military specifications and subgroup testing information please request Fairchilds Table | data sheet from your Fairchild sales engineer or account representative. Capacitance 54/74AC/IACT Symbol Parameter Units Conditions Typ Cin Input Capacitance 45 pF Vcc =5.5 V Power Dissipation 7 Cpp Capacitance 40.0 pF Vec=5.5V 5-42