W91440N Datasheet, PDF (2/14 Pages) Winbond – 10-MEMORY TONE/PULSE DIALER WITH SAVE FUNCTION

PIN CONFIGURATION
W91440N SERIES
C1 1
C2 2
C3 3
C4 4
C5 5
VSS
6
XT 7
XT
8
T/P MUTE
9
18 R4
17 R3
16 R2
15 R1
14 VDD
13 MODE
12 DTMF
11 _DP
10 _HKS
PIN DESCRIPTION
SYMBOL PIN I/O
FUNCTION
Column-
Row
Inputs
1−5
&
15−18
The keyboard inputs may be used with either a standard 5 × 5
I ^{keyboard or an inexpensive single contact (Form A) keyboard.}
Electronic input from a µC can also be used.
A valid key in is defined as a single row being connected to a single
column.
XT, XT
7, 8 I, O A built-in inverter provides oscillation with an inexpensive 3.579545
MHz crystal or ceramic resonator.
T/P
MUTE
9
O _{The T/P MUTE is a conventional CMOS N-channel open drain output.}
The output transistor is switched on during dialing sequence and flash
break time. Otherwise, it is switched off.
MODE
13
I Pulling mode pin to VSS places the dialer in tone mode.
Pulling mode pin to VDD places the dialer in pulse mode with M/B ratio
40:60 (10 ppS only for W91442N and 20 ppS for W91443N).
Floating mode pin places the dialer in pulse mode with M/B ratio 33:67
(10 ppS only for W91442N and 20 ppS for W91443N).
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