4

Application Information

Decoder Timing

t

RESP

t

DE

V

DD

NOTONE

NOTONE

OUTPUTS

Q0 to Q3

DATA CHANGE

SIGNAL IN

Tone 1

Tone 2

Tone 3

Tone ’N’

’N’

HOLD

PURS

HOLD

t

NORM

t

PUL

t

V

DD

SIGNAL IN

OUTPUTS

Q0 - Q3

DATA OUT Q0 - Q3

(INTERNAL)

DATA CHANGE

IRQ

CS

NOTONE

TRI-STATE

TRI-STATE

VALID DATA

(READ DATA)

VALID DATA

(READ DATA)

Tone 1

RIRQ

t

IR

t

ACS

t

HIZ

t

EF

1

PURS

Fig.4 Timing with the HOLD Input Held “High”;

CS and IRQ are used

Fig.3 Timing with the Chip Select Input Held “Low”;

CS and IRQ are not used