Datasheet

December 1990 4
Philips Semiconductors Product specification
Dual 4-bit synchronous binary counter 74HC/HCT4520
Fig.4 Functional diagram.
FUNCTION TABLE
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
↑ = LOW-to-HIGH clock transition
↓ = HIGH-to-LOW clock transition
nCP
0
nCP
1
MR MODE
↑ H L counter advances
L ↓ L counter advances
↓ X L no change
X ↑ L no change
↑ L L no change
H ↓ L no change
XXHQ
0
to Q
3
= LOW
Fig.5 Logic diagram (one counter).
Fig.6 Timing diagram.