SC91710A Datasheet, PDF (6/17 Pages) List of Unclassifed Manufacturers – TONE / PULSE SWITCHABLE DIALER WITH HANDFREE FUNCTION

SC91710A/B
(Continued)
Pin No.
Pin Name
SC91710A SC91710B
Description
* 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
10
12
HKS
power 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)
10
HFO
or 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 CO.,LTD
Http: www.silan.com.cn
REV:2.2 2007.03.07
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