MOSEL VITELIC INC.
Preliminary
MSS0271
Signals
SP+ and SP-
They are tristate during standby.
They are not at standby current when the data is in the
middle.
These two pins can drive buzzer or speaker, 8 ohm or
16 ohm, directly. The speaker used should have its
band width (BW) at the center of your sound frequency
domain or you are unable to play your sound good by
this speaker.
For instance, you have your sound spans over
frequency from 100 Hz through 10 KHz. A speaker with
BW meets requirement will play this sound good. A
speaker with BW narrower than requirement (either has
higher low-cut or lower high-cutoff) will distort the sound
very much because that most of the energy of the
playback sound is unable to be played by this speaker.
This pair has zero output when sound data is zero. This
pair has full output when sound data is the highest.
This pair has half of full output when sound is silence at
middle data value. This pair has half of full output when
playing sound at appended memory-less mute.
The output depends on Vdd bias very much.
Herein zero output does not mean zero potential,
neither ground.
It is recommended to select voltage source carefully
and do not supply this chip with a voltage potential
source in poor flatness or in poor drive capability.
What the poor source means either its potential drops
as the load varies or its potential drops as its capacity
exhausted.
The speaker characeristics and housing impacts the
loudness very much.
TG
This is a high true activating signal input pin.
internal pull low R TG is built in.
There is no schmit trigger circuit implemented.
An
Ramp up and Ramp down
See the explanation of Audio.
Sample Rate
All the AC parameters depend on sample rate except
three - t PUD, t P and t R. The numbers mentioned in this
data sheet are based on 6 KHz sample rate if not
specified. Higher SR has quicker LED flasher, quicker
response. Lower SR has slower LED flasher, slower
response.
Retriggerable TG
Retriggerable TG means the sound played could be
terminated immediately while further TG activated and
play the sound from the very beginning.
Holdable and retriggerable
This combination allows user controlling both the output
and the input. Its output is holdable and the input could
retrigger the former. This is an exquisite feature. It is not
provided on this single trigger voice chip.
Fix flash LED
Fix 3 Hz flash means this pin turns LED lamp on for T
LED3 and then turns it off for T LED3 alternately. Fix 6 Hz
flash means quicker, it turns on T LED6 and then turns off
T LED6.
The 3 Hz as well as 6 Hz is sample rate dependent.
When repeatedly playing a word, interesting LED flash
may happen in concatenation. The word length may not
be the multiples of T LED3 (or T LED6), a new flash cycle
will start before the last flash cycle terminates.
Dymanic Flash LED
The LED turns on whenever the sound amplitude (the
current from SPs) is over a certain threshold potential (I
LEDT). The sound potential could be measured in data
value as an alternative.
Debounce time
Either Fast or Slow debounce are provided by mask
options. The Fast debounce acknowledges very short
trigger. So, the sound will play "sensitively". User should
be very carefully to choose trigger switch while "Fast
debounce" is specified.
IN0 and IN1
They should be bonded to ground both regularly.
While abnormal lot (pitch shifted) is encountered,
special bonding could be done herein.
LB
This pin could be optionally masked as either high true
Busy signal or LED flasher which is turned on in sink
way by I LED. Refers to paragrahps "Mask option" and
"terms". Up to 3 types of LED flasher could be chosen.
Application Notes
Speaker
The typical application speaker is 8 ohm, 1/4 watt. Refers
to above paragraph SP+ and SP- for more description on
required speaker.
Buzzer
The recommended resonant frequency should be 1 KHz
to get the best sound response. The response BW also
should be fit to the required sound band width. Refer to
above paragraph SP+ and SP- for more description.
PID257*** 05/97
Terms
Audio
Audio means the signal from the pin pair SP+ and SP-.
Due to a sophisticated architecture, there demands no
ramp up (or ramp down) to eliminate the pop noise at
the sound starting and ending.
Specifications subject to change without notice, contact your sales representatives for the most recent information.
4/12
MOSEL [ MOSEL VITELIC, CORP ]
