W91810N Datasheet, PDF (5/26 Pages) Winbond – 23-MEMORY TONE/PULSE DIALER WITH HANDFREE, LOCK AND HOLD FUNCTIONS

W91810N SERIES
Pin Description, continued
SYMBOL 22-PIN 24-PIN 28-PIN I/O
FUNCTION
DTMF
14
16
19 O During pulse dialing, this pin remains in a low state
regardless of the keypad input. In tone mode, it will
output a dual or single tone.
A detailed timing diagram for tone mode is shown in
Figure 2(a, b).
OUTPUT FREQUENCY
Specified Actual Error %
R1
697
699 +0.28
R2
770
766
-0.52
R3
852
848
-0.47
R4
941
948 +0.74
C1
1209
1216
+0.57
C2
1336
1332
-0.30
C3
1477
1472
-0.34
VDD, VSS
V1, V2
HFI , HFO
16, 8
-
-
18, 8
-
12, 13
21, 9
14, 15
13, 16
I Power input pins for the dialer chip. V^DD is the power
and VSS is the ground.
O Volume control output pins. These two pins can be
toggled by the volume control keys (Vup, Vdown).
These two pins output is a conventional CMOS N-
channel open drain output.
I, O Handfree control pins.
A low pulse on the HFI input pin toggles the handfree
control state. The status of the handfree control state
is listed in the following table:
CURRENT STATE
NEXT STATE
HOOK SW. HFO INPUT
HFO DIALING
-
Low _HFI
High Yes
On Hook High _HFI
Low
No
Off Hook High _HFI
Low Yes
On Hook
- Off Hook Low Yes
Off Hook Low On Hook Low
No
Off Hook High On Hook High Yes
The ^HFI pin is pulled to V^DD by an internal resistor.
A detailed timing diagram is shown in Figure 3.
Publication Release Date: March 2000
-5-
Revision A5