-Allows any commercial microcontroller to control
the device
•Programmable Sampling Clock
-Allows user to choose quality and duration levels
•Single 3V power supply
•Low power consumption
-Playback operating current: 15 mA typical
-Standby current: 1 uA maximum
-Automatic power-down
•Multiple package options available
-CSP, PDIP, Bare Die
•On-board clock prescaler
-Eliminates the need for external clock dividers
•Automatic squelch circuit
Reduces background noise during quiet passages
-
General Description
Figure 1 APR6016 Pinout Diagrams
The APR6016 offers non-volatile storage of voice and/or data
in advanced Multi-Level Flash memory. Up to 16 minutes of
audio recordin
imum of 30K bits of di
devices can be cascaded for lon
g and playback can be accommodated. A max-
gital data can be stored.
APR6016
ger duration recording or
greater digital storage. Device control is accomplished
throu
gh an industry standard SPI interface that allows a
microcontroller to mana
This flexible arran
messa
ging options. The APR6016 is ideal for use in cellular
and cordless phones, telephone answerin
di
gital assistants, personal voice recorders, and voice pag-
ers.
APLUS Integrated
lity
by usin
i mplemented in an advanced non-volatile Flash memory
logy
g a proprietary analog multi-level storage te
process. Each memory cell can typically store 256 volta
levels. This allows the
si
gnals in their natural form, eliminating the need for en
The EXTCLK pin allows the use of an external samplin
clock. This input can accept a wide range of frequencies
dependin
that follows the clock. Alternativel
nal oscillator can be used to suppl
Mux followin
si
nal if a clock is present, otherwise the internal oscillator
source is chosen. Detailed information on how to pro
divider and internal oscillator can be found in the explanation
of the
Command Description
the appropriate sample clock fre
Sampling Rate & Voice Quality
The audio si
should be fed into the differential inputs ANAIN-, and
ANAIN+. After pre-amplification the si
anti-aliasin
its response based on the sample rate bein
nal anti-aliasin
After passin
the sample and hold circuit which works in con
the Analo
flash memor
on the divider ratio programmed into the divider
, the programmable inter-
the sampling clock. The
both signals automatically selects the EXTCLK
PWRUP
command, which appears in the
section. Guidance on how to choose
uency can be found in the
section.
nal containing the content you wish to record
nal is routed into the
filter. The anti-aliasing filter automatically adapts
used. No exter-
filter is therefore required.
through the anti-alias filter, the signal is fed into
Write Circuit to store each analog sample in a
cell.
OpCode
unction with
ram the
When a read operation is desired the Analog Read Circuit
extracts the analo
the si
nal to the Internal Low Pass Filter. The low pass filter
converts the individual samples into a continuous output. The
output si
ferential output driver. The differential output driver feeds the
ANAOUT+ and ANAOUT- pins. Both differential output pins
swin
The s
si
control si
reducin
mation, refer to the
After passin
oes to the output amplifier. The output amplifier drives a sinle ended output on the AUDOUT pin. The single ended out-
put swin
All SPI control and hand shakin
Master Control Circuit. This circuit decodes all the SPI si
and
the status re
the APR6016.
nal then goes to the squelch control circuit and dif-
around a 1.23V potential.
uelch control circuit automatically reduces the output
nal by 6 dB during quiet passages. A copy of the squelch
nal is present on the /SQLOUT pin to facilitate
ain in the external amplifier as well. For more infor-
s around a 1.23V potential.
enerates all the internal control signals. It also contains
data from the memory array and feeds
Squelch
through the squelch circuit the output signal
ister used for examining the current status of
section.
signals are routed to the
nals
Figure 2APR6016 Block Diagram
/RESET
/BUSY
SAC
/INT
DO
DI
/CS
SCLK
EXTCLK
Row
Address
Master Control Circuit
3.84 Mcell Memory Array
Row Decoder
Column Address
Programmable Internal
Oscillator
Programmable
Divider
Single Analog
Memory Cell
Column Decoder
Analog input/output
to Memory array
Mux
Low Pass
Write Circuit
Read Circuit
Low Pass
Squelch
Pre-
Amp
Amp
Amp
ANAIN+
ANAIN-
ANAOUT+
ANAOUT-
AUDOUT
SQLCAP
/SQLOUT
Page 2Voice Recording & Playback Device
Revision 1.0
Preliminary
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APR6016 Data Sheet
Memory Organization
The APR6016 memory array is organized to allow the greatest flexibilit
The smallest addressable memor
The APR6016 contains 1280 sectors.
in message management and digital storage.
unit is called a “sector”.
Figure 3 Memory Map.
SAC Trigger Point
Sector 0
Sector 1
Sector 1279
Sectors 0 through 1279 can be used for analog storage. Durin
audio recording one memory cell is used per sample
clock c
bit is programed into the memory. This prevents playback of
silence when partial sectors are used. Unused memor
exists between the EOD bit and the end of the sector can not
be used.
Sectors 0 throu
stora
store data but have not been tested, and are thus not
teed to provide 100%
error correction or forward check-before-store methods.
Once a write c
chosen sector is lost.
Mixin
not possible.
cle. When recording is stopped an end of data (EOD
e. Other sectors, with the exception of sector 1279, can
audio signals and digital data within the same sector is
Note: There are a total of 15bits reserved for addressing. The
APR6016 only requires 11 bits. The additional 4 bits are used
for larger device within the APR60XX family.
Can Not be Used for Digital Data
that
h 9 are tested and guaranteed for digital
uaran-
ood bits. This can be managed with
cle is initiated all previously written data in the
SPI Interface
All memory management is handled by an external host processor. The host processor communicates with the APR6016
throu
h a simple Serial Peripheral Interface (SPI) Port. The
SPI port can run on as little as three wires or as man
seven dependin
section will describe how to mana
APR6016's SPI Port and associated OpCode commands.
This topic is broken down into the followin
• Sendin
• OpCode Command Description
• Receivin
• Current Device Status
• Reading the Silicon Identification (SID)
•Writin
• Readin
• Recordin
•Pla
• Handshakin
Sending Commands to the Device
This section describes the process of sendin
the APR6016. All Opcodes are sent in the same wa
exception of the
The
in the
that follow. The minimum SPI confi
commands uses the DI, /CS, and SCLK pins. The device will
accept inputs on the DI pin whenever the /CS pin is low.
OpCode commands are clocked in on the risin
SPI clock. Fi
OpCode commands into the device. Figure 5 is a description
of the OpCode stream.
You must wait for a command to finish executin
in
/BUSY pin. You can substitute monitorin
inserting a fixed delay between commands. The required
dela
shows the timin
mands. Table 1 describes which
Digital Data
Back Audio Data
DIG_WRITE and DIG_READ
Writing Digital Data
a new command. This is accomplished by monitoring the
is measured from the extra clock low that follows the 8K sampling rate: 376m SEC
next3
OpCode Command Description
Designers have access to a total of 14 OpCodes. These
OpCodes are listed in Table 2. The name of the Opcode
appears in the left hand column. The followin
represent the actual binar
information contained in the 20 bit
data stream. Some commands have limits on which com-
two columns
next1 5u SEC
next2 5m SEC
T
next2 5m SEC
Within SAC Low Time
T
next3
4K sampling rate: 752m SEC
next4 470m SEC
mand can follow them. These limits are shown in the “
able Follow on Commands
” column. The last column
Allow-
summarizes each command.
Combinations of OpCodes can be used to accommodate
almost an
All CommandsErases all data contained in specified sec-
All CommandsThis command reads data bits D0 - D3003
STOP,
STOP_PWDN,
SET_FWD, FWD,
SET_PLAY,PLAY,
NOP
STOP_PWDN,
SET_FWD, FWD,
SET_PLAY,PLAY,
NOP
Starts a record operation from the sector
address specified.
Starts a record operation from the current
sector address.
tor. You must not erase a sector before
recording voice signals into it. You must
erase a sector before storing digital data in
it.
starting at the specified address. All 3004
bits must be written.
starting at the specified address.
Starts a play operation from the sector
address specified.
Starts a play operation from the current
sector address.
NOP
The
most often used when readin
more information on readin
Device Status
THE
of its silicon ID re
ing the SID
The
from the be
command performs no operation in the device. It is
the current device status. For
device status see the
section.
SID
operation instructs the device to return the contents
ister. For more information see the
section.
SET_FWD
command instructs the device to fast forward
inning of the sector specified in the OpCode
Current
Read-
parameter field. The device will fast forward until either an
EOD bit, or the end of the sector is reached. If no EOD bit or
forthcomin
command has been received when the end of
the sector is reached, the device will loop back to the be
nin
of the same sector and begin the same process again. If
an EOD bit is found the device will stop and
enerate an
interrupt on the /INT pin. The output amplifiers are muted durin
this operation.
FWD
The
command instructs the device to fast forward from
the start of the current sector to the next EOD marker. If no
EOD marker is found within the current sector the device will
increment to the next se
Page 6Voice Recording & Playback Device
uential sector and continue looking.
The device will continue to fast forward in this manner until
either an EOD is reached, a new command is sent, or the end
of the memor
the device will stop and
The output amplifiers are muted durin
PWRUP
The
mode and set the internal clock fre
array is reached. When an EOD is reached
enerate an interrupt on the /INT pin.
this operation.
command causes the device to enter power up
uency and EXTCLK
divider ratio. The PWRUP command must be used to force
the device into power up mode before an
commands can be
executed. To select an Internal oscillator fre
[A1 - A0] bits accordin
in-
A1A0Sample rate
to the following binary values:
006.4 kHz
014.0 kHz
108.0 kHz
115.3 kHz
If
ou are using an external sample clock signal you must
also set the EXTCLK divider ratio. This divider ratio is e
uency set the
ual
Revision 1.0
Preliminary
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APR6016 Data Sheet
to N:1 where N is an integer between 1 and 256, excluding 2.
The N value should be selected to satisf
tion as closel
EXTCLK fre
Example:
Suppose that 8.0 KHz samplin
the fre
N
Roundin
The Op Code Parameter bit stream, composed of bits
[A9 - A2][A1 - A0], therefore becomes binar
[00001000][10].
STOP
The
operation.
STOP_PWDN
The
current command and enter power down mode. Durin
down the device consumes si
PWRUP command must be used to force the device into
power up mode before an
SET_REC
The
recordin
continue to record until the end of the current sector is
reached. If no forthcomin
when the end of the sector is reached the device will loop
back to the be
previousl
SET_REC
mand immediatel
that no audio information is lost. For more information see the
section entitled
REC
The
the current sector. If no new command is received before the
device reaches the end of the sector the device will automaticall
increment to the next sequential sector and continue
recordin
until the memor
command is received. For more information see the section
entitled
DIG_ERASE
The
sector specified. Erase should not be done before recordin
voice signals into a sector. Erase must be done before storin
digital data in a sector.
DIG_WRITE
The
the specified sector. All 3K bits must be written, no partial
usa
e of the sector is possible. The memory acts as a FIFO,
the first data bit shifted in will be the first data bit shifted out. A
sector must be erased usin
BEFORE
tion on storin
Digital Data
as possible:
= (N) * (128) * (selected sampling frequenc
uency of the signal present on EXTCLK = 8MHz.
8000000
---------- ------------- --128 8000()
up, N = 8
Command causes the device to stop the current
at the sector address specified. The device will
recorded material. If the next command is another
REC
or
7.8125==
command causes the device to stop the
nificantly less power. The
commands can be executed.
command instructs the device to begin
command has been received
inning of the same sector and overwrite the
command the device will execute the com following the end of the current sector so
Recording Audio Data
command instructs the device to begin recording in
. The device will continue to record in this manner
is exhausted or a
Recording Audio Data
command erases all data contained in the
command stores 3K bits of digital data in
data can be written to the sector. For more informa-
digital data, see the section entitled
.
.
the
the following equa-
is desired. Assume that
power
.
STOP
DIG_ERASE
STOP_PWDN
or
command
Writing
DIG_READ
The
di
ital data that was previously written to the specified sector.
The first bit shifted out is the first bit that was written. The last
bit shifted out is the last bit that was written. For more information on readin
command instructs the device to retrieve
digital data see the section entitled
Read-
ing Digital Data.
SET_PLAY
The
back at the specified sector. If no forthcomin
received, or EOD bit encountered, before the end of the sector is reached the device will loop back to the be
same sector and continue pla
the audio output. If the next command is another
PLAY
or
immediatel
ap in playback is present. For more information see the sec-
tion entitled
PLAY
The
the current sector. If no forthcomin
EOD bit encountered, before the device reaches the end of
the sector the device will automaticall
se
uential sector and continue playing. The device will con-
tinue to pla
STOP
a
information see the section entitled
or
command instructs the device to begin play-
command is
inning of the
back with no noticeable gap in
SET_PLAY
command the device will execute the command
following the end of the current sector so that no
The device communicates data to the user by shifting out
data on the DO pin. The device will shift out data accordin
the timin
Figure 7 Data Out Timing
parameters given in figure 7. The device can shift
/CS
SCLK
DI
DO
Op4
Op3
D0
Op2Op1
D1 D2 D18 D17 D19 D16
D3
to
~
~
~
~
~
~
~
~
out three different t
con ID, and user stored di
ID are described in the next two sections. Retrieval of user
data is described in the
A3
D15
A2
pes of data streams: Device status, Sili-
ital data. Device status and silicon
Reading Digital Data
A1
A0
section.
T
fcsDO
Current Device Status (CDS)
As described in the previous section, three different types of
data streams are shifted out on the DO pin as data is shifted
in on the DI pin. One of these streams is the current device
status. The CDS will be shifted out unless the previous command is SID command. Fi
CDS bit stream. The first bit shifted out, D0, is the Overflow
fla
. The Overflow flag is set to a binary 1 if an attempt was
made to record be
fla
is set to a 0 if an overflow has not occurred. This flag is
Figure 8 Format for CDS Bit Stream
D19
Sector Address MSBSector Addr
ond the available memory. The Overflow
~
T
fSCLK
ure 8 shows the format of the
}
~
Sector Address
ess LSB
T
hzD0
cleared after it has been read. The D1 bit is the End of Data
. The EOD flag is set when the device stops playing, or
fla
fast forwardin
fla
is cleared after it has been read. The D2 bit is the Illegal
Address fla
al address is sent to the device. The D3 bit is the Lbat flag.
This fla
below specification. The D4 bit is not used and should be
i
nored. The last fifteen bits represent the address of the cur-
rent or last active sector.
as a result of an EOD bit in memory. The EOD
. The Illegal Address flag is set whenever an ille-
is set when the device senses a supply voltage
First bit shifted outLast bit shifted out
D0 D1 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D2
OVF
EOD
al Address
Ille
Lbat
Page 8Voice Recording & Playback Device
Revision 1.0
Preliminary
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APR6016 Data Sheet
Reading the SID
Each device in the APR60XX series family contains an
embedded Silicon Identification
b
the host processor to identify which family / family member
is bein
Figure 9 SID Timing
used. Reading the device SID requires issuing two
SCLK
/CS
DI
DO
SID CommandNext Command
CDS Output Data
SID). The SID can be read
OpCode commands; a SID command followed b
command, usuall
the SID data out on the DO pin as the command that follows
the SID command is clocked in. Fi
describes the process necessar
a NOP command. The device will clock
ure 9 is a diagram that
for reading SID information.
SID Output Data
any other
The SID information follows the format given in Figure 10.
The first bit shifted out, D0, is the Overflow bit. The Overflow
bit is set to a binar
be
ond the available memory. The Overflow bit is set to a 0 if
an overflow has not occurred. This bit is cleared after it has
been read. The D1 bit is the End Of Data
bit is set when the device stops pla
a result of EOD bit in memor
has been read. The D2 bit is the Ille
al Address Bit is set whenever an illegal address is sent to
Figure 10 SID Bit Stream
~
D19
}
Ignore These
Bits
1 if an attempt was made to record
EOD) bit. The EOD
or fast forwarding as
. The EOD bit is cleared after it
al Address Bit. The Ille-
~
}
Device
Code
00
0
}
APR6016 Device
Code (Binar
1
the device. The D3 bit is the Lbat bit. This bit is set when the
device senses a suppl
lowin
five bits represent the product family. The APR60XX
product famil
The next four bits represent the device code. The APR6016
device code is binar
seven bits are random data and should be i
Digital data is written into the device using the
command. No mixing of analog data and digital data within a
sector is possible. Sectors 0 throu
anteed for di
ital storage. Other sectors, with the exception of
h 9 are tested and guar-
sector 1279, can store data but have not been tested, and
are thus not
be mana
store methods. Issuin
1279 will cause data throu
A sector must be erased, usin
before di
necessar
uaranteed to provide 100% good bits. This can
ed with error correction or forward check-before-
DIG_ERASE
a
command on sector
hout all sectors to be lost.
DIG_ERASE
the
ital data can be written to it. This requirement is
whether analog data or digital data was previousl
stored in the sector. A sector should not be erased more than
once between analo
or digital write operations. Executin
multiple erase operations on a sector will permanently dama
e the sector. A sector can be reallocated to either analo
storage or digital storage at any time.
The process of storin
DIG_WRITE
command. The
lowed immediatel
stored in the arra
digital data begins by sending a
DIG_WRITE
four buffer bits. These bits will not be
and must be considered don’t care bits.
DIG_WRITE
command,
command is fol-
Figure 11 Writing Digital Data
Immediatel
that
following the four buffer bits should be the data
ou wish to store. All 3004 bits must be stored. Four
additional buffer bits must be clocked into the device followin
the stored data. These bits will not be stored in the arra
and must be considered don’t care bits. Ending a digital write
command earl
will permanently damage the sector.
The DO pin will clock out the normal 20 bit CDS followed b
five don’t care bits, a copy of the 3004 data bits, and finall
three don’t care bits.
ure 11 shows a timing diagram which describes the digital
Fi
stora
e process. All timing with the exception of T
pSCLK
should adhere to the specifications given in Figure 4 and Figure 7. The T
specification is replaced by the DT
pSCLK
pSCLK
when storing digital data. The /BUSY pin indicates when a
DIG_WRITE
is taking place.
Note: The DIG_ERASE command should not be used before
storing analog data. The device will perform its own internal
erase before analog storage.
Figure 11 does not show the DIG_ERASE command which
must be executed on a sector before digital data can be
stored.
SCLK
/CS
D I
DO
/BUSY
DIG_WRITECOMMAND
CDS
X
X
X
X
XXX
Total 3032 clock c
X
X
cles
3004 bits of data to be stored
Four Don’t Care Bits
Copy of the input data (delayed one clock cycle)
X
XXX
X
X
X
Page 10Voice Recording & Playback Device
Revision 1.0
Preliminary
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APR6016 Data Sheet
Reading Digital Data
Digital data is read from the device using the
command. To read data you must send a
mand immediatel
same /CS c
sector will be
followed by 3012 don’t care bits during the
cle. The data previously stored in the specified
in to appear on the DO pin after the current
device status or SID and four buffer bits. The next 3004 bits
are the previousl
stored data. The first bit shifted out is the
first bit that was written. The last bit shifted out is the last bit
that was written. There are four random don’t care bits followin
the 3004 bits of user data.
DIG_READ
DIG_READ
com-
Figure 12 Reading Digital Data
SCLK
Total 3032 clock cycles
/CS
DI
DIG_READ COMMAND
An incomplete read of the sector is allowed. An incomplete
read is defined a a read with less than 3032 clock c
incomplete read c
the /CS si
ure 12 shows a timing diagram which describes the entire
Fi
nal returns high.
process for a complete sector read. All timin
tion of T
Fi
b
When a
be
ANAIN- to the specified sector. After half the sector is used
the SAC pin will drop low to indicate that a new command can
be accepted. The device will accept commands as lon
the SAC pin remains low. An
SAC returns hi
next SAC c
Fi
se
SET_REC
or
SET_REC
in sampling and storing the data present on ANAIN+ and
cle.
ure 13 shows a typical timing diagram and OpCode
uence for a recording operation. In this example the
command begins recording at the specified mem-
location after T
Figure 13 Typical Recording Sequence
SCLK
/CS
REC
or
h will be queued up and executed during the
arec
command is issued the device will
as
command received after the
time has passed. Some time later the
low
oing edge on the SAC pin alerts the host processor that
the first sector is nearl
issuing a
The
recordin
tor. When the first sector is full the device automaticall
to the next sector and returns the SAC si
to indicate that the second sector is now bein
point the host processor decides to issue a
durin
command and terminates recording after TS
pin indicates when actual recordin
REC
command before the SAC pin returns high.
REC
command instructs the APR6016 to continue
in the sector immediately following the current sec-
the next SAC cycle. The device follows the
full. The host processor responds b
nal to a high state
used. At this
STOP
command
.The /BUSY
is taking place.
arec
umps
STOP
DI
SAC
ANAIN+
ANAIN-
/BUSY
SET_REC
T
arec
REC
STOP
TS
arec
Page 12Voice Recording & Playback Device
Revision 1.0
Playing Back Audio Data
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When a
will be
duce a resultant output on the AUDOUT, ANAOUT-, and
ANAOUT+ pins. After half the sector is used the SAC pin will
drop low to indicate that a new command can be accepted.
The device will accept commands as lon
remains low. An
hi
c
Fi
se
mand be
SET_PLAY
in sampling the data in the specified sector and pro-
h will be queued up and executed during the next SAC
cle.
ure 14 shows a typical timing diagram and OpCode
uence for a playback operation. The
ins playback at the specified memory location after
PLAY
or
command received after the SAC returns
command is issued the device
as the SAC pin
SET_PLAY
com-
Figure 14 Typical Playback Sequence
SCLK
/CS
Preliminary
APR6016 Data Sheet
T
time has passed. Some time later the low going edge
aplay
on the SAC pin alerts the host processor that half of the first
sector has been pla
b
issuing a
PLAY
command instructs the APR6016 to continue playback
of the sector immediatel
the first sector has been pla
next sector and returns the SAC si
cate that the second sector is now bein
the host processor decides to issue a
the next available SAC low time. The device follows the
STOP
/BUSY pin indicates when actual pla
PLAY
command and terminates playback after TS
ed back. The host processor responds
command during the SAC low time. The
following the current sector. When
ed back the device jumps to the
nal to a high state to indi-
played. At this point
STOP
command durin
. The
back is taking place.
aplay
DI
SAC
ANAOUT+
ANAOUTANAOUT
/BUSY
Note: Command timing is not to scale
SET_PLAY
T
aplay
PLAY
Handshaking signals
Several signals are included in the device that allow for handshakin
si
scheme used.
The /INT si
cessor when attention is re
normall
An interrupt is
. These signals can simplify message management
nificantly depending on the message management
nal can be used to generate interrupts to the pro-
uired by the APR6016 This pin is
high and goes low when an interrupt is requested.
enerated whenever a EOD or Overflow
STOP
TS
aplay
occurs.
The SAC si
nearin
a record, pla
normall
rentl
active segment has been played or recorded. The signal returns to a hi
pla
ed or recorded. The microprocessor should sense the
low ed
nal is used to determine when the device is
the end of the current memory segment during either
or forward operation. The SAC signal is in a
high state. The signal goes low after half the cur-
h state after the entire segment has been
e of the SAC signal as an indicator that the next seg-
ment needs to be selected, and do so before the SAC signal
returns hi
current se
pla
recordin
The /BUSY pin indicates when the device is performin
a pla
tion. The host microprocessor can monitor the bus
confirm the status of these commands. The /BUSY pin is normall
time is
ified b
h. Failing to specify the next command before the
ment is exhausted (either during recording or
back) will result in a noticeable gap during playback or
.
either
, record, DIG_WRITE, DIG_READ or fast forward func-
pin to
high and goes low while the device is busy. The low
overned by the length of recording or playback spec-
the user.
Sampling Rate and Voice Quality
The Nyquist Sampling Theorem requires that the highest fre-
uency component a sampling system can accommodate
without the introduction of aliasin
samplin
input, based on the selected samplin
re
Hi
hence voice
same amount of recordin
dates samplin
Lower samplin
increase the duration capabilities of the device, but also
reduce recordin
rates as low as 4 kHz.
Desi
controlling the sampling frequency. Sampling frequency can
be controlled b
can chan
internal oscillator is used or an external clock is used.
frequency. The APR6016 automatically filters its
uirement.
her sampling rates increase recording bandwidth, and
uality, but also use more memory cells for the
rates as high as 8kHz.
rates use less memory cells and effectivel
bandwidth. The APR6016 allows samplin
ners can thus control the quality/duration trade-off b
using the PWRUP command. This command
e sampling frequency regardless of whether the
errors is equal to half the
frequency, to meet this
time. The APR6016 ccommo-
Storage Technology
The APR6016 stores voice signals by sampling incomin
voice data and storing the sampled signals directly into
FLASH memor
ran
es from 1 to 256 levels. These 256 discrete voltage levels are the e
values. Durin
memor
amplified before being fed to an external speaker amplifier.
, smoothed to form a continuous signal and finall
cells. Each FLASH cell can support voltage
uivalent of eight (28=256) bit binary encoded
playback the stored signals are retrieved from
Squelch
The APR6016 is equipped with an internal squelch feature.
The S
uelch circuit automatically attenuates the output signal
b
6 dB during quiet passages in the playback material. Mut-
in
the output signal during quiet passages helps eliminate
back
round noise. Background noise may enter the system
in a number of wa
natural noise present in some power amplifier desi
induced throu
The response time of the s
time constant of the capacitor connected to the SQLCAP pin.
The recommended value of this capacitor is 1.0 uF. The
s
uelch feature can be disabled by connecting the SQLCAP
pin to VCC.
The active low output /SQLOUT
nal s
uelch activates. This signal can be used to squelch the
output power amplifier. S
results in further reduction of noise; especiall
power amplifier is runnin
s including: present in the original signal,
ns, or
h a poorly filtered power supply.
uelch circuit is controlled by the
oes low whenever the inter-
uelching the output amplifier
when the
at high gain & loud volumes.
The APR6016 derives its samplin
sources: internal or external. If a clockin
the EXTCLK input the device will automaticall
as the samplin
EXTCLK input the device automaticall
nal clock source. When the EXTCLK pin is not used it should
be tied to GND.
An internal clock divider is provided so that external clock si
nals can be divided down to a desired samplin
allows hi
the EXTCLK pin. Usin
allowing use of a clock already present in the system, as
opposed to havin
custom clock. Details for pro
described in the SPI interface section under the PWRUP
para
raph.
The default power up condition for the APR6016 is to use the
internal oscillator at a samplin
Page 14Voice Recording & Playback Device
clock source. If no input is present on the
h frequency signals of up to 10 MHz to be fed into
this feature simplifies designs b
to generate or externally divide down a
clock from one of two
signal is present on
use this signal
defaults to the inter-
-
rate. This
raming the clock divider are
frequency of 6.4 kHz.
Revision 1.0
Sample Application
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Figure 15 shows a sample application utilizing a generic
microcontroller and SPI interface for messa
e management.
APR6016 Data Sheet
speaker. Several vendors suppl
ers that can be used for this purpose.
integrated speaker amplifi-
Preliminary
The microcontroller uses three
pla
, record and skip buttons. Five general purpose I/O sig-
eneral purpose inputs for the
nals are utilized in the SPI interface. The /RESET and /BUSY
si
nal are not used in this design.
The output si
nal must be amplified in order to drive a
Figure 15 Sample Schematic using DIP package
Vcc
Generic
I/O _1
I/O_2
I/O_3
I/O_4
I/O_5
Microcontroller
F
0.1
I/O _6
/IR Q
I/O _7
I/O _8
/CS
DI
DO
VSSD
NC
NC
NC
ANAOUT-
ANAOUT+
NC
/RESET
VSSA
AUDOUT
SQLCAP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
All resistors 2.2 K
Pla
Record
Skip
A microphone amplifier and AGC are recommended. Both
blocks are optional. Several vendors suppl
integrated micro-
phone/AGC amplifiers that can be used for this purpose.
Note that the AGC circuit can be simplified by using the SQLCAP signal as a
peak detector signal.
Table three shows pin descriptions for the APR6016 device.
All pins are listed in numerical order with the exception of
Table 3 APR6016 28 Pin Number & Description
Pin Name
SAC 24 27
/INT 25 28
EXTCLK 26 29
SCLK 28 33
/CS 1 2
DI 2 3
DO 3 4
ANAOUT- 8 9
ANAOUT+ 9 10
/RESET 11 11
AUDOUT 13 15
SQLCAP 14 16
/SQLOUT 15 17
ANAIN- 16 18
Pin No.
28 pin
DIP
Pad No. (Die)
Reference Figure
18
Sector Address Control Output: Th
device is nearing the end of the current segment.
Interrupt Output: T
device reaches the end of a message or the device overflows. When connected
to the interrupt input of the host microcontroller this output can be used to implement powerful message management options.
External Clock Input: T
sample clock instead of using the internal sampling clock. This pin should be connected to VSSA when not in use.
SPI Clock Input: D
ing edge of this clock. Data is clocked out of the part through the DO pin on the
falling edge.
Chip Select Input: T
slave on the SPI interface. When this pin is high the device tri-states the DO pin
and ignores data on the DI pin.
Data Input:
Data is clocked on the rising edge of the SCLK input.
Data Output: D
Negative Audio Output:
recorded messages. This output is usually fed to the negative input of a differential input power amplifier. The power amplifier drives an external speaker.
Positive Audio Output:
recorded messages. This output is usually fed to the positive input of a differential
input power amplifier. The power amplifier drives an external speaker.
Reset Input: T
restores the device to its power up defaults.
Single Ended Audio Output: T
recorded messages. This output is usually fed to the input of a power amplifier for
driving an external speaker.
Squelch Capacitor I/O:
Connect this pin to GND through a 1.0 uf capacitor to enable the squelch feature.
The capacitor’s time constant will affect how quickly the squelch circuitry reacts.
Connect this pin to VCCA to disable the squelch feature.
Squelch Output:
squelch circuitry has activated. This signal can be used to automatically squelch
the external power amplifier. Squelching the external power amplifier can result in
an even greater reduction of background noise.
Inverting Analog Input: T
the user wishes to record. When the device is used in a differential input configuration this pin should receive a 16 mV peak to peak input coupled through a
0.1uF capacitor. When the device is used in a single ended input configuration
this input should be tied to VSSA through a 0.1 uF capacitor.
VCC, VSS and NC pins which are listed at the end of the
table.
Functionality
is active low output indicates when the
his active low open drain output goes low whenever the
his input can be used to feed the device an external
ata is clocked into the device through the DI pin upon the ris-
his active low input selects the device as the currently active
The DI input pin receives the digital data input from the SPI bus.
ata is available after the falling edge of the SCLK input.
This is the negative audio output for playback of pre-
This is the positive audio output for playback of pre-
his active low input clears all internal address registers and
his is the audio output for playback of pre-
This pin controls the attack time of the squelch circuitry.
This active low open drain output indicates when the internal
his input is the inverting input for the analog signal that
Page 16Voice Recording & Playback Device
Revision 1.0
Preliminary
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APR6016 Data Sheet
Pin NamePin No.
28 pin
TSOP
ANAIN+ 17 19
/BUSY 21 23
VCCD 27 30, 31, 32
VCCA 18 20, 21
VSSA 12,23 12, 13, 14, 24,
VSSD 4 5, 6
NC 5, 6, 7,
Pin No.
28 pin
DIP
10, 19,
20, 22
Pad No. (Die)
Reference Figure
18
25, 26
1, 7, 8, 22
Functionality
Non-Inverting Analog Input: T
signal that the user wishes to record. When the device is used in a differential
input configuration this pin should receive a 16 mV peak to peak input coupled
through a 0.1 uF capacitor. When the device is used in a single ended input configuration this pin should receive a 32 mV peak to peak input coupled through a
0.1 uF capacitor.
Busy Output: T
DIG_WRITE, DIG_READ or fast forward operation. The pin is tri-stated otherwise. This pin can be connected to an LED to indicate playback/record operation
to the user. This pin can also be connected to an external microcontroller as an
indication of the status of playback, record, forward, or digital operation.
Digital Power Supply: T
cuitry. This pin should be connected to the 3.0 V power plane through a via. This
pin should also be connected to a 0.1 uF bypass cap as close to the pin as possible.
Analog Power Supply: T
circuitry. This pin should be connected to the 3.0 V power plane through a via.
This pin should also be connected to a 0.1 uF bypass cap as close to the pin as
possible.
Analog Ground:
via. The connection should be made as close to the pin as possible.
Digital Ground: Th
The connection should be made as close to the pin as possible.
No Connect:
nection of these pins to any signal, GND or VCC may result in incorrect device
behavior or cause damage to the device.
his active low output is low during either a record, playback,
These pins should be connected to the ground plane through a
is pin should be connected to the ground plane through a via.
These pins should not be connected to anything on the board. Con-
his input is the non-inverting input for the analog
his connection supplies power for all on-chip digital cir-
his connection supplies power for all on-chip analog
Electrical Characteristics
The following tables list Absolute Maximum Ratings, Recom-
Absolute Maximum Ratings
Stresses greater than those listed in Table 4 may cause permanent dama
sent a stress ratin
an
other conditions above those specified in the recom-
e to the device. These specifications repre-
only. Operation of the device at these or
Table 4Absolute Maximum Ratings.
ItemSymbolConditionMinMaxUnit
Power Supply voltage
Input Voltage
Storage Temperature
Temperature Under Bias
Lead Temperature
T
V
V
T
T
CC
IN
STG
BS
LD
TA = 25 C
TA = 25 C
Device VCC = 3.0 V-0.35.5V
mended DC Characteristics, and recommended AC Characteristics for the APR6016 device.
mended DC Characteristics or recommended AC Characteristics of this specification is not implied. Maximum conditions
for extended periods ma