74F533

OCTAL TRANSPARENT LATCH (3-STATE OUTPUTS)


Family
Fairchild FAST (Advanced Schottky TTL)
Source
1980 Fairchild FAST Data Book, pages 4-108 ... 4-109
Status
PRELIMINARY -- page 4-108 carries a "Preliminary" watermark.
Ratings
Vcc = +5.0 V +/-5%, TA = 0 to +70 deg C

DESCRIPTION | CONNECTION DIAGRAM (20-pin DIP) | INPUT LOADING / FAN-OUT | DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE | AC CHARACTERISTICS | AC OPERATING REQUIREMENTS | VERILOG MODEL

DESCRIPTION

The 'F533 consists of eight latches with 3-state outputs for bus
organized system applications. The flip-flops appear transparent to the
data when Latch Enable (LE) is HIGH. When LE is LOW, the data that meets
the setup times is latched. Data appears on the bus when the Output
Enable (/OE) is LOW. When /OE is HIGH the bus output is in the high
impedance state. The 'F533 is the same as the 'F373, except that the
outputs are inverted. For description and logic diagram please see the
'F373 data sheet.

  o EIGHT LATCHES IN A SINGLE PACKAGE
  o 3-STATE OUTPUTS FOR BUS INTERFACING

CONNECTION DIAGRAM (20-pin DIP)

Pin  Function                           Pin  Function
---  ---------------------------------  ---  ---------------------------------
  1  /OE  Output Enable (active LOW)     20  Vcc
  2  /O0  Complementary latch output 0   19  /O7  Complementary latch output 7
  3  D0   Data input 0                   18  D7   Data input 7
  4  D1   Data input 1                   17  D6   Data input 6
  5  /O1  Complementary latch output 1   16  /O6  Complementary latch output 6
  6  /O2  Complementary latch output 2   15  /O5  Complementary latch output 5
  7  D2   Data input 2                   14  D5   Data input 5
  8  D3   Data input 3                   13  D4   Data input 4
  9  /O3  Complementary latch output 3   12  /O4  Complementary latch output 4
 10  GND                                 11  LE   Latch Enable (active HIGH)

INPUT LOADING / FAN-OUT

Pin Names    Description                       U.L. HIGH/LOW
-----------  --------------------------------  -------------
D0 - D7      Data Inputs                       0.5 / 0.375
LE           Latch Enable Input (Active HIGH)  0.5 / 0.375
/OE          Output Enable Input (Active LOW)  0.5 / 0.375
/O0 - /O7    Complementary 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)        35       mA

Conditions:  Vcc = Max, /OE = 4.5 V;  Dn, LE = Gnd.

AC CHARACTERISTICS

Symbol      Parameter                    Min  Typ  Max  Units
----------  ---------------------------  ---  ---  ---  -----
tPLH        Propagation Delay Dn to /On   --  5.3   --  ns
tPHL        Propagation Delay Dn to /On   --  3.7   --  ns
tPLH        Propagation Delay LE to /On   --  9.2   --  ns
tPHL        Propagation Delay LE to /On   --  4.2   --  ns
tPZH, tPZL  Output Enable Time            --   --   --  ns
tPHZ, tPLZ  Output Disable Time (1)       --   --   --  ns

(1) Disable times measured with CL = 5.0 pF.

AC OPERATING REQUIREMENTS

Symbol  Parameter                     Min  Typ  Max  Units
------  ----------------------------  ---  ---  ---  -----
ts (H)  Setup Time, HIGH -- Dn to LE  3.0   --   --  ns
ts (L)  Setup Time, LOW -- Dn to LE   3.0   --   --  ns
th (H)  Hold Time, HIGH -- Dn to LE   2.0   --   --  ns
th (L)  Hold Time, LOW -- Dn to LE    2.0   --   --  ns
tw (H)  LE Pulse Width HIGH           6.0   --   --  ns

Data sheet transcription as plain text

VERILOG MODEL

// ============================================================================
// f533.v — 54F/74F533 Octal Transparent Latch, Inverting
//          (With 3-State Outputs)
//
// Fairchild FAST (Advanced Schottky TTL)
// Source: docs/devices/54F74F533.txt (1980 Fairchild FAST Data Book,
//         pages 4-108 ... 4-109) — PRELIMINARY data sheet.
//
// Eight D-type latches with inverting 3-state outputs: the same as the
// 'F373 except the outputs are inverted. While Latch Enable (LE) is HIGH
// the latches are transparent: O_n follows the complement of D_n. When LE
// is LOW the latches hold the data present a setup time before the
// HIGH-to-LOW LE transition. Output Enable (OE_n) LOW drives the outputs;
// OE_n HIGH forces the high-impedance state without disturbing the latches.
//
// Timing values from the data sheet AC Characteristics table
// (T_A = +25 C, V_CC = +5.0 V, C_L = 15 pF). The preliminary sheet gives
// TYP ONLY for D_n->O_n and LE->O_n (min/max columns blank), and leaves
// the enable/disable rows entirely blank; the sheet itself gives the 'F373
// enable/disable figures as an order-of-magnitude guide, so those
// (min:typ:max) are used for the OE_n path and marked as such below.
//
// Ports are scalar and named after the data sheet pin names: Icarus Verilog
// does not fully support multi-bit (parallel) specify path connections, so
// vector ports would get incorrect per-bit delays. The complementary
// outputs O_n-bar are named o0_n ... o7_n (cf. q_n in f74).
// ============================================================================
`timescale 1ns/100ps

module f533 (
    input  wire oe_n,                           // output enable (active LOW)
    input  wire le,                             // latch enable (active HIGH)
    input  wire d0, d1, d2, d3,                 // data inputs 0-3
    input  wire d4, d5, d6, d7,                 // data inputs 4-7
    output wire o0_n, o1_n, o2_n, o3_n,         // complementary 3-state
    output wire o4_n, o5_n, o6_n, o7_n          //   latch outputs 0-7
);

    // Transparent latch bank: Q follows D while LE is HIGH, holds while LOW.
    reg [7:0] q_int;

    always @(*) begin
        if (le) q_int <= {d7, d6, d5, d4, d3, d2, d1, d0};
    end

    // Inverting 3-state output buffers (OE_n HIGH -> high impedance)
    assign o0_n = oe_n ? 1'bz : ~q_int[0];
    assign o1_n = oe_n ? 1'bz : ~q_int[1];
    assign o2_n = oe_n ? 1'bz : ~q_int[2];
    assign o3_n = oe_n ? 1'bz : ~q_int[3];
    assign o4_n = oe_n ? 1'bz : ~q_int[4];
    assign o5_n = oe_n ? 1'bz : ~q_int[5];
    assign o6_n = oe_n ? 1'bz : ~q_int[6];
    assign o7_n = oe_n ? 1'bz : ~q_int[7];

    specify
        // Propagation delay D_n to O_n (data sheet, TYP ONLY — preliminary
        // sheet, min/max blank: tPLH 5.3, tPHL 3.7 ns)
        specparam tlh_d_o  = 5.3;
        specparam thl_d_o  = 3.7;

        // Propagation delay LE to O_n (data sheet, TYP ONLY: tPLH 9.2,
        // tPHL 4.2 ns)
        specparam tlh_le_o = 9.2;
        specparam thl_le_o = 4.2;

        // Output enable/disable time OE_n to O_n: the F533 sheet leaves
        // these rows blank; values below are from the F373 data sheet,
        // which the F533 doc gives as an order-of-magnitude guide
        // (tPZH 3.0/6.8/11, tPZL 3.0/6.0/10, tPHZ 3.0/5.7/9.0,
        // tPLZ 3.0/6.2/9.0 ns; disable times measured with C_L = 5 pF).
        specparam tzh_oe_o = 3.0:6.8:11;
        specparam tzl_oe_o = 3.0:6.0:10;
        specparam thz_oe_o = 3.0:5.7:9.0;
        specparam tlz_oe_o = 3.0:6.2:9.0;

        // 6-delay form, IEEE order (0->1, 1->0, 0->Z, Z->1, 1->Z, Z->0):
        // D_n causes only 0->1/1->0 transitions, OE_n only Z transitions.
        (oe_n, d0 => o0_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d1 => o1_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d2 => o2_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d3 => o3_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d4 => o4_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d5 => o5_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d6 => o6_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);
        (oe_n, d7 => o7_n) = (tlh_d_o, thl_d_o, tlz_oe_o, tzh_oe_o, thz_oe_o, tzl_oe_o);

        (le => o0_n) = (tlh_le_o, thl_le_o);
        (le => o1_n) = (tlh_le_o, thl_le_o);
        (le => o2_n) = (tlh_le_o, thl_le_o);
        (le => o3_n) = (tlh_le_o, thl_le_o);
        (le => o4_n) = (tlh_le_o, thl_le_o);
        (le => o5_n) = (tlh_le_o, thl_le_o);
        (le => o6_n) = (tlh_le_o, thl_le_o);
        (le => o7_n) = (tlh_le_o, thl_le_o);

        // AC operating requirements (data sheet, +25 C 5.0 V minima):
        // ts(H) 3.0, ts(L) 3.0, th(H) 2.0, th(L) 2.0, tw(H) LE 6.0 ns.
        // Setup/hold are relative to the HIGH-to-LOW LE edge that closes
        // the latch. Icarus Verilog does not support timing checks; kept
        // (guarded) for simulators that do.
`ifndef __ICARUS__
        specparam ts_h = 3.0;
        specparam ts_l = 3.0;
        specparam th_h = 2.0;
        specparam th_l = 2.0;
        specparam tw_le_h = 6.0;

        $setup(d0, negedge le, ts_h);
        $setup(d1, negedge le, ts_h);
        $setup(d2, negedge le, ts_h);
        $setup(d3, negedge le, ts_h);
        $setup(d4, negedge le, ts_h);
        $setup(d5, negedge le, ts_h);
        $setup(d6, negedge le, ts_h);
        $setup(d7, negedge le, ts_h);
        $hold(negedge le, d0, th_h);
        $hold(negedge le, d1, th_h);
        $hold(negedge le, d2, th_h);
        $hold(negedge le, d3, th_h);
        $hold(negedge le, d4, th_h);
        $hold(negedge le, d5, th_h);
        $hold(negedge le, d6, th_h);
        $hold(negedge le, d7, th_h);
        $width(posedge le, tw_le_h);
`endif
    endspecify

endmodule

f533.v as plain text


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