ht9320b Holtek Semiconductor Inc., ht9320b Datasheet - Page 4

• Manufacturer Part Number: ht9320b
• Description: 22-memory Tone/pulse Dialer
• Manufacturer: Holtek Semiconductor Inc.

Memory dialing vs. keyboard form table
Pin Description
Rev. 1.10
Pin Name
C1~C8
R1~R5
X1
X2
XMUTE
HKS
PO
MODE
DTMF
Dialing Output
M11~M20
M1~M10
I/O
I/O
I/O
O
O
O
O
I
I
CMOS IN/OUT
OSCILLATOR
Connection
NMOS OUT
CMOS OUT
CMOS OUT
CMOS IN
Internal
IN/OUT
CMOS
M1 ~ M10
M11 ~ M20
Memory Keyboard
One-Touch
These pins form a 5 8 keyboard matrix which can perform keyboard input de-
tection and dialing specification setting functions. When on-hook (HKS=high)
all the pins are set high. While off-hook the column group (C1~C8) remains
low and the row group (R1~R5) is set high for key input detection.
For the HT9320L-X, the column group remains high and the row group is set
low for key input detection.
An inexpensive single contact 5 8 keyboard can be used as an input device.
Pressing a key connects a single column to a single row, and actuates the sys-
tem oscillator that results in a dialing signal output. If more than two keys are
pressed at the same time, no response occurs. The key-in debounce time is
20ms. Refer to the keyboard information for keyboard arrangement and to the
functional description for dialing specification selection.
The system oscillator consists of an inverter, a bias resistor and the necessary
load capacitor on chip. Connecting a standard 3.579545MHz crystal or ce-
ramic resonator to the X1 and X2 terminals can implement the oscillator func-
tion. The oscillator is turned off in the standby mode, and is actuated
whenever a keyboard entry is detected.
XMUTE is an NMOS open drain structure pulled to VSS during dialing signal
transmission. Otherwise, it is an open circuit. XMUTE is used to mute the
speech circuit when transmitting the dial signal.
This pin is used to monitor the status of the hook-switch and its combination
with HFI/HDI can control the PO pin output to make or break the line.
HKS=VDD: On-hook state (PO=low). Except for HFI/HDI (hand-free/hold-line
control input), other functions are all disabled.
HKS=VSS: Off-hook state (PO=high). The chip is in the stand-by mode and
ready to receive the key input.
This pin is a CMOS output structure which by receiving the HKS and
HFO/HDO signals, control the dialer to connect or disconnect the telephone
line.
PO outputs a low to break line when HKS is high (on-hook) and HFO/HDO is
low. PO outputs a high to make line when HKS is low (off-hook) or HFO is high
or HDO is high.
During the off-hook state, this pin also outputs the dialing pulse train in pulse
mode dialing. While in the tone mode, this pin is always high.
This is a three-state input/output pin, used for dialing mode selection, either
Tone mode or Pulse mode, 10pps/20pps
MODE=VDD: Pulse mode, 10pps
MODE=OPEN: Pulse mode, 20pps
MODE=VSS: Tone mode
During the pulse mode dialing, switching this pin to the tone mode changes
the subsequent digit entry to the tone mode. When the chips are in tone mode,
switching to the pulse mode will also be recognized.
This pin is active only when the chip transmits tone dialing signals. Otherwise,
it always outputs a low. The pin outputs tone signals to drive the external
transmitter amplifier circuit. The load resistor should not be less than 5k .
4
PAGE Ma (Ma=M1~M10)
Memory Keyboard
A
Two-Touch
a (a=1~9, 0)
Description
A PAGE a (a=1~9, 0)
Memory Keyboard
HT9320 Series
Three-Touch
October 1, 2002