HD74HC149
HD74HC149 is 8-to-8-line Priority Encoder manufactured by Renesas.
8-to-8-line Priority Encoder
REJ03D0574-0200 (Previous ADE-205-448)
Rev.2.00 Oct 11, 2005
Description
The HD74HC149 is priority encoder which has 8 input lines (0
- 7) and 8 output lies (Y0
- Y7).
It is the logical bination of a HD74HC148 8-3 line priority encoder driving a HD74HC138 3-8 line decoder.
Only one request output can be low at a time. The output that is low is dependent on the highest priority request that is low. The order of priority is 7 highest and 0 lowest.
When E input is high, all outputs are high.
When a output (Y0
- Y7) is low, P output is low and this indicates active condition.
Features
- High Speed Operation: tpd (0
- 7 to Y) = 16 ns typ (CL = 50 pF)
-...
