Datasheet

6
ICM7228
Timing Diagrams
FIGURE 1. ICM7228A/B WRITE CYCLE FIGURE 2. ICM7228A/B SEQUENTIAL 8-DIGIT RAM UPDATE
FIGURE 3. ICM7228C WRITE CYCLE
FIGURE 4. DISPLAY DIGITS MULTIPLEX (COMMON ANODE DISPLAY)
t
MS
t
WL
t
DS
t
MH
MODE
INPUT
VALID
DATA
t
DH
t
WH
WRITE
DECODE/NO DECODE? ID5
(D8)(D1)
MODE
CONTROL WORD
TYPE OF DECODER?ID6
DECODE/NO DECODE? ID5
SHUTDOWN?ID4
DATA COMING ID7
CONTROL WORD
TYPE OF DECODER?ID6
SHUTDOWN? ID4
DATA COMING ID7
DON’T CARE
WRITE DATA
8 PULSES
WRITE
VALID DATA
VALID
t
WL
t
WH
t
AS
t
AH
t
DH
t
DS
DATA
WRITE
DIGIT
ADDRESS
DAO-DAZ
INTERDIGIT BLANKING
INTERNAL SIGNAL
TYPICAL DIGITS
OUTPUT PULSES
10µs (TYP)
FREE RUNNING
320µs (TYP)
FREE RUNNING (PER DIGIT)
INTERDIGIT BLANKING
D2
D5
D1
D7
D8
D6
D4
D3