IL91350A
Pin Description
Pin No.
1-4
17 - 20
5
Designation
Column-Row
Inputs
H/P MUTE
Description
The Keyboard input may be used with the standard 4 x 5 keyboard.
A valid key entry is defined by a single row being connected to a single
column.
The H/P MUTE is a conventional inverter output.
In pulse dialing, flash and hold period, the output will be at active high,
otherwise, it will keep at low state.
Power supply pins.
This device is designed to operate from 2.0 V to 5.5 V.
A built in inverter provides oscillation with an inexpensive 3.579545 MHz
crystal or ceramic resonator.
The oscillator output pin.
The T/P MUTE is a conventional CMOS N-channel open drain output.
The output transistor is switched on during Pulse and Tone mode dialing
sequence and Flash break. Ohterwise, it is switched off.
Handfree control pins.
When HFI input pin has a low pulse, the handfree control state is toggled
on.
Status of the handfree control state is listed in the following table:
CURRENT STATE
Hook SW.
HFO
X
Low
On Hook
High
Off Hook
High
On Hook
X
Off Hook
Low
Off Hook
High
NEXT STATE
Input
HFO
Dialing?
HFI
High
Yes
HFI
Low
No
HFI
Low
Yes
Off Hook
Low
Yes
On Hook
Low
No
On Hook
High
Yes
6
16
7
8
9
GND
V
CC
XT
XT
T/P MUTE
10, 11
HFI, HF0
HFI pin is pulled to V
CC
by internal resistor.
X = don’t care.
12
HKS
This pin is the hook switch input.
HKS = H, ON HOOK state, chip in sleeping mode, no operation.
HKS = L, OFF HOOK state, enable chip on normal operation.
This pin must combine to HFI, HFO to perform the above function.
Please refer to HFI, HFO pin.
HKS pin is pulled to V
CC
by internal resistor.
Open drain dialing pulse output.
Flash key will cause DP active either in Tone mode or Pulse mode.
In pulse mode, it always keeps at low state.
In tone mode, it will output a dual or single tone.
Pull mode pin to GND; the dialer is in Tone mode.
Pull mode pin to V
CC
; the dialer is in Pulse mode - 10 pps, M/B=2/3.
Pull mode pin to floating; the dialer is in Pulse mode - 10 pps, M/B=1/2.
13
14
15
DP/C5
DTMF
MODE
INTEGRAL [ INTEGRAL CORP. ]
