ISD5008 Datasheet, PDF (9/47 Pages) List of Unclassifed Manufacturers – SINGLE CHIP VOICE RECORD PLAYBACK DEVICE 4-, 5-, 6-, AND 8- MINUTE DURATIONS

ISD5008 Product
ANAOUT+/– (Analog Outputs)
This differential output is designed to go to the mi-
crophone input of the telephone chip set. It is de-
signed to drive a minimum of 5 kΩ between the
“+” and “–” pins to a nominal voltage level of
700 mVp-p. Both pins have DC bias of approxi-
mately 1.2 VDC. The AC signal is superimposed
upon this analog ground voltage. These pins can
be used single-ended, getting only half the volt-
age. Do NOT ground the unused pin.
2.3 POWER AND GROUND PINS
V_CCA, V_CCD (Voltage Inputs)
To minimize noise, the analog and digital circuits
in the ISD5008 device uses separate power bus-
ses. These +3 V busses lead to separate pins. Tie
the V_CCD pins together as close as possible and
decouple both supplies as near to the package
as possible.
AUX OUT (Auxiliary Output)
The AUXOUT is an additional audio output pin, to
be used, for example, to drive the speaker circuit
in a “car kit.” It drives a minimum load of 5 kΩ and
up to a maximum of 1 Vp-p. The AC signal is su-
perimposed on approximately 1.2 VDC bias and
must be capacitively coupled to the load.
SP+, SP– (Speaker+/–)
This is the speaker differential output circuit. It is de-
signed to drive an 8 Ω speaker connected across
the speaker pins up to a maximum of 23.5 mW
power. This stage has two selectable gains, 1.32
and 1.6, which can be chosen through the con-
figuration registers. These pins are biased to ap-
proximately 1.2 VDC and, if used single-ended,
must be capacitively coupled to their load. Do
NOT ground the unused pin.
V_SSA, V_SSD (Ground Inputs)
The ISD5008 series utilizes separate analog and
digital ground busses. The analog ground (V_SSA)
pins should be tied together as close to the pack-
age as possible and connected through a low-
impedance path to power supply ground. The
digital ground (V_SSD) pin should be connected
through a separate low-impedance path to pow-
er supply ground. These ground paths should be
large enough to ensure that the impedance be-
tween the V_SSA pins and the V_SSD pin is less than
3 Ω. The backside of the die is connected to V_SSD
through the substrate resistance. In a chip-on-
board design, the die attach area must be con-
nected to V_SSD.
ACAP
(AGC Capacitor)
This pin provides the capacitor connection for
setting the parameters of the microphone AGC
circuit. It should have a 4.7 µF capacitor con-
nected to ground. It cannot be left floating. This is
because the capacitor is also used in the
playback mode for the AutoMute circuit. This
circuit reduces the amount of noise present in the
output during quiet pauses. Tying this pin to
ground gives maximum gain; to V_CCA gives
minimum gain for the AGC amplifier but will
cancel the AutoMute function.
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