ISD1964SYI Datasheet, PDF (16/29 Pages) List of Unclassifed Manufacturers – SINGLE-CHIP, MULTIPLE-MESSAGE VOICE RECORD/PLAYBACK DEVICE

ISD1900
Addr/Drct
<S3:S0>
<E3:E0>
T_ASet
REC
LED
T_Deb
T_AHold
Mic+/-
T_Ers
or AnaIn
PlayE
SP+
SP-
T_Settle1 T_Settle3
T_Deb
Figure 6-7 An example of Playback supersedes Record
T_EOM
6.1.5 XCLK Feature
25
• When precision sampling frequency is required, external clock mode can be activated by setting ¯X¯C¯L¯K¯
to Low. Under such condition, the resistor at Rosc pin must be removed and the external clock signal
must be applied to the Rosc pin. These conditions must be satisfied prior to any operations.
• However, when internal clock is used, ¯X¯C¯L¯K¯ must be linked to High.
• The external clock frequencies required for various sampling frequencies are listed in below table.
Sampling Freq [kHz]
12
8
6.4
5.3
4
¯X¯C¯L¯K¯ [MHz]
3.072
2.048
1.638
1.356
1.024
6.2. DIRECT MODE
15
• The Direct Mode is selected by the ¯D¯r¯c¯t pin. Once chosen, the supply voltage must be reset to allow
the device to construct itself to the appropriate configuration by re-defining the function on the related
control pins. Also, the mode change is only allowed while the device is in power down state and is
inhibited when an operation is in progress.
• Once Direct Mode is activated, FMC1, FMC2 & FMC3 are utilized to select various (1 to 8) fixed
message configurations ^[1]. Pending upon the arrangement on FMC1, FMC2 & FMC3, each divided
message has approximate equal length of duration, which is related to the number of rows assigned as
in tables below.
• The record or playback operation is pre-defined by the ¯R¯/P pin. Setting this pin to Low allows record
operation while setting it to High enables playback operation.
• Each message can be randomly accessed via its message control pin (M¯¯1 ~ M¯¯8) and the desired
operations are facilitated accordingly. Non-configured pins are automatically disabled and must be
floated.
Publication Release Date: Jan 5, 2009
16
Revision 0.51