74F350

4-BIT SHIFTER WITH 3-STATE OUTPUTS


Family
Fairchild FAST (Advanced Schottky TTL)
Source
1985 Fairchild FAST Data Book, pages 4-213 ... 4-217. The 1980 data book carries the 'F350 in its Section 3 selection guide only (page 3-33, description and logic symbol).
Status
Released data sheet
Ratings
Vcc = +5.0 V +/-5%, TA = 0 to +70 deg C

DESCRIPTION | FUNCTIONAL DESCRIPTION | CONNECTION DIAGRAM (16-pin DIP) | TRUTH TABLE | INPUT LOADING / FAN-OUT | DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE | AC CHARACTERISTICS

DESCRIPTION

The 'F350 is a specialized multiplexer that accepts a 4-bit word and
shifts it 0, 1, 2 or 3 places, as determined by two Select (S0, S1)
inputs. For expansion to longer words, three linking inputs are provided
for lower-order bits; thus two packages can shift an 8-bit word, four
packages a 16-bit word, etc. Shifting by more than three places is
accomplished by paralleling the 3-state outputs of different packages
and using the Output Enable (/OE) inputs as a third Select level. With
appropriate interconnections, the 'F350 can perform zero-backfill,
sign-extend or end-around (barrel) shift functions.

  o Linking Inputs for Word Expansion
  o 3-State Outputs for Extending Shift Range

FUNCTIONAL DESCRIPTION

The 'F350 is operationally equivalent to a 4-input multiplexer with the
inputs connected so that the select code causes successive one-bit
shifts of the data word. This internal connection makes it possible to
perform shifts of 0, 1, 2 or 3 places on words of any length.

A 7-bit data word is introduced at the In inputs and is shifted
according to the code applied to the select inputs S0, S1. Outputs
O0-O3 are 3-state, controlled by an active LOW output enable (/OE). When
/OE is LOW, data outputs will follow selected data inputs; when HIGH,
the data outputs will be forced to the high impedance state. This
feature allows shifters to be cascaded on the same output lines or to a
common bus. The shift function can be logical, with zeros pulled in at
either or both ends of the shifting field; arithmetic, where the sign
bit is repeated during a shift down; or end around, where the data word
forms a continuous loop.

Logic equations
~~~~~~~~~~~~~~~
    O0 = /S0*/S1*I0 + S0*/S1*I-1 + /S0*S1*I-2 + S0*S1*I-3
    O1 = /S0*/S1*I1 + S0*/S1*I0  + /S0*S1*I-1 + S0*S1*I-2
    O2 = /S0*/S1*I2 + S0*/S1*I1  + /S0*S1*I0  + S0*S1*I-1
    O3 = /S0*/S1*I3 + S0*/S1*I2  + /S0*S1*I1  + S0*S1*I0

CONNECTION DIAGRAM (16-pin DIP)

Pin  Function                 Pin  Function
---  -----------------------  ---  -----------------------
  1  I-3  Linking input -3     16  Vcc
  2  I-2  Linking input -2     15  O0   Output 0
  3  I-1  Linking input -1     14  O1   Output 1
  4  I0   Data input 0         13  /OE  Output Enable
  5  I1   Data input 1         12  O2   Output 2
  6  I2   Data input 2         11  O3   Output 3
  7  I3   Data input 3         10  S0   Select input 0
  8  GND                        9  S1   Select input 1

I-3, I-2 and I-1 are the linking inputs that carry the three
lower-order bits from the next package down when shifters are cascaded.

TRUTH TABLE

  Inputs           Outputs
------------  ------------------
/OE  S1   S0   O0   O1   O2   O3
---  ---  ---  ---  ---  ---  ---
 H    X    X    Z    Z    Z    Z
 L    L    L   I0   I1   I2   I3
 L    L    H   I-1  I0   I1   I2
 L    H    L   I-2  I-1  I0   I1
 L    H    H   I-3  I-2  I-1  I0

H = HIGH voltage level;  L = LOW voltage level;  X = immaterial;
Z = high impedance.

INPUT LOADING / FAN-OUT

Pin Names   Description                       U.L. HIGH/LOW
----------  --------------------------------  -------------
S0, S1      Select Inputs                     0.5 / 0.75
I-3 - I3    Data Inputs                       0.5 / 0.75
/OE         Output Enable Input (Active LOW)  0.5 / 0.75
O0 - O3     3-State Outputs                   75 / 15

DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE

Symbol  Parameter             Min  Typ  Max  Units  Conditions
------  --------------------  ---  ---  ---  -----  -------------------------
ICCH    Power Supply Current        22   35  mA     Outputs HIGH, Vcc = Max
ICCL    Power Supply Current        27   41  mA     Outputs LOW,  Vcc = Max
ICCZ    Power Supply Current        26   42  mA     Outputs OFF,  Vcc = Max

AC CHARACTERISTICS

                                              TA = +25 C      74F
                                              Vcc = +5.0V     TA/Vcc = Com
Symbol  Parameter                      CL     Min  Typ   Max  Min  Max   Units
------  -----------------------------  -----  ---  ----  ---  ---  ----  -----
tPLH    Prop Delay In to On            50 pF  3.0   4.5  6.0  3.0   7.0  ns
tPHL    Prop Delay In to On            50 pF  2.5   4.0  5.5  2.5   6.5  ns
tPLH    Prop Delay Sn to On            50 pF  4.0   7.8 10.0  4.0  11.0  ns
tPHL    Prop Delay Sn to On            50 pF  3.0   6.5  8.5  3.0   9.5  ns
tPZH    Output Enable Time             50 pF  2.5   5.0  7.0  2.5   8.0  ns
tPZL    Output Enable Time             50 pF  4.0   7.0  9.0  4.0  10.0  ns
tPHZ    Output Disable Time            50 pF  2.0   3.9  5.5  2.0   6.5  ns
tPLZ    Output Disable Time            50 pF  2.0   4.0  5.5  2.0   6.5  ns

Data sheet transcription as plain text

VERILOG MODEL

No model for this device yet — only the data sheet transcription above.


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