SC91710A Datasheet, PDF (6/18 Pages) List of Unclassifed Manufacturers – TONE / PULSE SWITCHABLE DIALER WITH HANDFREE FUNCTION

Silan
Semiconductors
SC91710A/B
( continued )
Pin No.
SC91710
Pin Name
SC91710B
A
Description
*Mute output pins.
*NMOS open drain output structure.
7
XMUTE *The output is in “LOW” state during dialing sequence (both Pulse and
7
Tone
mode) otherwise this pin is “high-impedance”.
*Long (continue) Mute.
8
8
VSS *Negative power supply pin.
9
11
VDD *Positive power supply pin.
*Hook switch input pin.
*When the handset is in ON-HOOK state, this pin must be pulled “high” in
order to disable the dialing operation and decrease the power
10
12
HKS
consumption.
*When in OFF-HOOK state, the HKS pin must be pulled “low” state for
all function operation.
*Pulse output signal pin.
*NMOS open drain output structure.
11
13
PO
*The output is “LOW” during pulse dialing and Flash operation, otherwise
this output is “floating”.
*Dual Tone Multi-frequency output pin.
*In TONE mode, when an entry of digit key (include *, # key), this pin will
send out a corresponding DTMF signal.
12
14
TONE *The TONE pin provides minimum tone duration and minimum intertone
pause time to support rapid key-in. If key-in time is less than 100ms,
DTMF signal will last for 100ms; otherwise the tone duration will last as
long as the key is pressed.
* Handfree input control pin.
* Toggle input structure, falling edge trigger.
* It is used to enable and disable Handfree function.
9
HFI
* With waveshaped by a built-in Schmit trigger, the bounce of input can be
eliminated by external R, C debounce circuit.
* A built-in pull down resistor is 200k typical.
* Handfree output control pin.
* Inverter output structure (normally ‘low’, active ‘high’).
* When a HFI pin is active, Handfree function will be enabled (HFO=1) or
10
HFO
disable (HFO=0).
* When the Handfree function is enable (HFO=1), after OFF-HOOK action,
it can reset Handfree function and HFO pin return to ‘low’ state.
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
2001-11-13
6