GA3219 Datasheet, PDF (11/14 Pages) Gennum Corporation – Venture-TM Digital DSP System

VENTURE GA3219
(if enabled), and after switching to the next memory, the
audio signal is faded back in. The memory switch fader is
also used when turning the Tone Generator on or off, and
during SDA programming.
Power−On/Power−Off Behaviour and Low Battery
Indicator
During power−on, the Venture GA3219 hybrid is held in
a reset state until the supply voltage (V_b) reaches a turn−ON
threshold. A small portion of the hybrid’s internal control
logic turns on and monitors the voltage to determine if the
supply is stable. Once the supply is stable, the entire hybrid
is activated and loads its configuration. Finally, the audio
output turns on by smoothly transitioning to the expected
output level.
During normal operation, when a low battery condition is
detected, the Venture GA3219 hybrid sends out a series of
one to seven beeps (each beep is 512 ms ON and 512 ms
OFF) to indicate the battery is low. This is repeated every
five minutes until the device reaches the turn−OFF
threshold. The low battery threshold is programmable in
IDS between 1.0 V and 1.2 V in 10 mV increments.
If V_b drops below the turn−OFF threshold, then the
Venture GA3219 hybrid is returned to its reset state and the
audio output is muted. After a reset due to a low battery or
a sudden supply transient, the recovery behaviour of the
Venture GA3219 is determined by the selectable reset mode
through ARKonline.
There are four selectable reset modes as follows:
• Shallow−reset mode − After a low battery shutdown or
transient shutdown, it allows the Venture GA3219
hybrid to immediately restart when the supply voltage
rises above the turn−ON threshold. The device restarts
in the memory that was last active when the shut down
occurred. In summary, the device functions until the
supply voltage drops below the turn−OFF threshold,
and recovers when the device rises above the turn−ON
threshold again.
• Deep−reset mode − After a low battery shutdown or
transient shutdown, it does not allow the Venture
GA3219 hybrid to restart. When a shutdown occurs
(i.e., the supply voltage drops below the turn−OFF
threshold), the device remains off until the supply
voltage drops below approximately 0.3 V and
subsequently rises above the turn−ON threshold. For
the supply to drop below 0.3 V, the battery should be
disconnected. Upon reconnecting the battery
(preferably a new battery) the supply voltage rises
above the turn−ON threshold, and depending if the
supply is stable, the device restarts.
• Mixed mode − A combination of the first two modes.
The device starts up in shallow−reset mode initially,
then transitions to deep reset mode after five minutes.
• Advanced reset mode (recommended) − A more
advanced combination of the first two modes, plus
some additional intelligence. The device starts up in
shallow−reset mode initially, so that after a low battery
shutdown or a transient shutdown, the device
immediately restarts when the supply voltage rises
above the turn−ON threshold. When the device restarts,
deep−reset mode is applied and the device operates in
the memory that was last active when the shut down
occurred. Additionally, the maximum output level is
reduced through a 2 dB reduction of the AGC−O and
peak clipper. This operating condition is defined as
transient reboot mode. The device operates in transient
reboot mode (i.e., deep−reset mode and maximum
output reduction are applied) while monitoring the
supply voltage. If the supply voltage remains above the
turn−ON threshold for at least 30 secs, the device is
allowed to exit transient reboot mode. The device
returns to shallow−reset mode and the maximum output
is restored.
Generally, any low battery shutdown or transient
shutdown that occurs while in shallow−reset mode (or while
in the shallow−reset mode component of mixed mode or
advanced reset mode) results in the Venture GA3219 hybrid
restarting into the memory that was last active when the shut
down occurred. The Venture GA3219 hybrid has this
memory restart capability for up to three memories. A restart
in any memory beyond the first three memories causes the
device to restart in the initial memory, similar to the
behaviour when a battery is first connected. The transient
reboot mode described above also applies to up to three
memories. Any additional memories would use the
shallow−reset mode behaviour, and would restart in the
initial memory after a shutdown.
In any of the above reset modes, the Venture GA3219
hybrid can be configured through ARKonline to reduce the
gain as the battery voltage drops. When the supply voltage
falls below the low battery threshold, low battery tones are
emitted and the wideband gain is reduced by 3 dB. As the
battery voltage continues to drop, the low battery tones
continue and the wideband gain continues to be reduced.
Once the turn−OFF threshold is reached, the device shuts
down.
Software and Security
Venture GA3219 incorporates the following security
features to protect the device from cloning and against
software piracy:
• DLL protection by password − prevents a third party
from using IDS to reconfigure parts.
• Hybrid authentication by 128−bit fingerprint to identify
parts in application software − prevents a third party
from cloning a device’s EEPROM because the
fingerprint cannot be overwritten. Special functions can
be used in fitting software to reject parts that do not
match the expected fingerprint. This would prevent the
piracy of fitting software.
• DLL to hybrid pairing by using a software key in ARK
to match product libraries with client software − a part
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