74148.yaml

---
description:  8-to-3 line priority encoder
package:      DIP
pincount:     16
family:       "7400"
datasheet:    "http://www.ti.com/lit/ds/scls109g/scls109g.pdf"
pins:
  - num:  1
    sym:  4
    desc: decimal data input (active low)
  - num:  2
    sym:  5
    desc: decimal data input (active low)
  - num:  3
    sym:  6
    desc: decimal data input (active low)
  - num:  4
    sym:  7
    desc: decimal data input (active low)
  - num:  5
    sym:  EI
    desc: enable input (active low)
  - num:  6
    sym:  A2
    desc: binary address output (active low)
  - num:  7
    sym:  A1
    desc: BCD address output (active low)
  - num:  8
    sym:  GND
    desc: ground
  - num:  9
    sym:  A0
    desc: binary address output (active low)
  - num:  10
    sym:  0 
    desc: decimal data input (active low)
  - num:  11
    sym:  1 
    desc: decimal data input (active low)
  - num:  12
    sym:  2
    desc: decimal data input (active low)
  - num:  13
    sym:  3 
    desc: decimal data input (active low)
  - num:  14
    sym:  GS
    desc: goes low when EI is low and any input is low
  - num:  15
    sym:  EO
    desc: goes high when EI is low and any input is low (EO = ~GS~)
  - num:  16
    sym:  Vcc
    desc: supply voltage
specs:
  - param:  Propagation delay, n to An 
    val:    [16 (74HC)]
    unit:   ns
notes:
  - When two or more inputs are simultaneously active, the input with the highest priority is represented on the output.
  - Input 7 has the highest priority.
  - When all eight data inputs are high, all three outputs are high.
  - Multiple 74148s can be cascaded by connecting EO of the high priority chip to EI of the low priority chip (see datasheet).
...