======================================================================== 74F539 DUAL 1-OF-4 DECODER (3-STATE OUTPUTS) ======================================================================== Family: Fairchild FAST (Advanced Schottky TTL) Source: 1980 Fairchild FAST Data Book, pages 4-118 ... 4-120 Status: PRELIMINARY -- page 4-118 carries a "Preliminary" watermark. Ratings: Vcc = +5.0 V +/-5%, TA = 0 to +70 deg C DESCRIPTION ----------- The 'F539 contains two independent decoders. Each accepts two Address (A0, A1) input signals and decodes them to select one of four mutually exclusive outputs. A polarity control input (P) determines whether the outputs are active-HIGH (P = L) or active-LOW (P = H). An active-LOW input Enable (/E) is available for data demultiplexing; data is routed to the selected output in non-inverted form in the active-LOW mode or in inverted form in the active-HIGH mode. A HIGH signal on the active-LOW Output Enable (/OE) input forces the 3-state outputs to the high impedance state. CONNECTION DIAGRAM (20-pin DIP) -------------------------------- Pin Function Pin Function --- ------------------------------- --- ------------------------------- 1 O2b Side B Output 2 20 Vcc 2 O1b Side B Output 1 19 O3b Side B Output 3 3 O0b Side B Output 0 18 A1b Side B Address input 1 4 Pb Side B Polarity Control 17 A0b Side B Address input 0 5 /OEb Side B Output Enable (LOW) 16 /Eb Side B Enable (active LOW) 6 A0a Side A Address input 0 15 /Ea Side A Enable (active LOW) 7 A1a Side A Address input 1 14 /OEa Side A Output Enable (LOW) 8 O3a Side A Output 3 13 Pa Side A Polarity Control 9 O2a Side A Output 2 12 O0a Side A Output 0 10 GND 11 O1a Side A Output 1 TRUTH TABLE (each half) ------------------------ H = HIGH voltage level; L = LOW voltage level; X = immaterial; Z = high impedance state. Function /OE /E A1 A0 O0 O1 O2 O3 -------------- --- -- -- -- -- -- -- -- High Impedance H X X X Z Z Z Z Disable L H X X On = P Active-HIGH L L L L H L L L Output L L L H L H L L (P = L) L L H L L L H L L L H H L L L H Active-LOW L L L L L H H H Output L L L H H L H H (P = H) L L H L H H L H L L H H H H H L INPUT LOADING / FAN-OUT ------------------------ Pin Names Description U.L. HIGH/LOW ----------- -------------------------------- ------------- A0a - A1a Side A Address Inputs 0.5 / 0.375 A0b - A1b Side B Address Inputs 0.5 / 0.375 /Ea, /Eb Enable Inputs (Active LOW) 0.5 / 0.375 /OEa, /OEb Output Enable Inputs (Active LOW) 0.5 / 0.375 Pa, Pb Polarity Control Inputs 0.5 / 0.375 O0a - O3a Side A 3-State Outputs 25 / 12.5 O0b - O3b Side B 3-State Outputs 25 / 12.5 DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE ----------------------------------------------------- Symbol Parameter Min Typ Max Units ------ -------------------------------------- --- --- --- ----- ICC Power Supply Current (All Outputs OFF) 42 mA Conditions: A0, A1, /E = Gnd; /OE, P = HIGH. (Printed as a single row; not broken out per side on the data sheet.) AC CHARACTERISTICS ------------------ Symbol Parameter Min Typ Max Units ------ --------------------------------- --- ---- --- ----- tPLH Propagation Delay An to On -- 12.5 -- ns tPHL Propagation Delay An to On -- 11.5 -- ns tPLH Propagation Delay /E to On -- 11.5 -- ns tPHL Propagation Delay /E to On -- 11 -- ns tPLH Propagation Delay P to On -- 13 -- ns tPHL Propagation Delay P to On -- 12 -- ns tPZH Output Enable Time /OE to On -- 5.0 -- ns tPZL Output Enable Time /OE to On -- 5.5 -- ns tPHZ Output Disable Time (1) /OE to On -- 5.0 -- ns tPLZ Output Disable Time (1) /OE to On -- 5.0 -- ns (1) Disable times measured with CL = 5.0 pF.