25-08-2017, 09:32 PM
APR9600 multi-section sound recorder/replay IC
and experimental board
[attachment=45886]
APR9600 is a low-cost high performance sound record/replay IC incorporating flash analogue
storage technique. Recorded sound is retained even after power supply is removed from the
module. The replayed sound exhibits high quality with a low noise level. Sampling rate for a 60
second recording period is 4.2 kHz that gives a sound record/replay bandwidth of 20Hz to 2.1 kHz.
However, by changing an oscillation resistor, a sampling rate as high as 8.0 kHz can be achieved.
This shortens the total length of sound recording to 32 seconds.
Total sound recording time can be varied from 32 seconds to 60 seconds by changing the value of a
single resistor. The IC can operate in one of two modes: serial mode and parallel mode.
In serial access mode, sound can be recorded in 256 sections. In parallel access mode, sound can be
recorded in 2, 4 or 8 sections. The IC can be controlled simply using push button keys. It is also
possible to control the IC using external digital circuitry such as micro-controllers and computers.
The APR9600 has a 28 pin DIP package. Supply voltage is between 4.5V to 6.5V. During
recording and replaying, current consumption is 25 mA. In idle mode, the current drops to 1 mA.
The APR9600 experimental board is an assembled PCB board consisting of an APR9600 IC, an
electret microphone, support components and necessary switches to allow users to explore all
functions of the APR9600 chip. The oscillation resistor is chosen so that the total recording period
is 60 seconds with a sampling rate of 4.2 kHz. The board measures 80mm by 55mm.
APR9600
Pin-out of the APR9600 is given in Figure 1. A typical
connection of the chip is given in Figure 2 (This is the
circuit diagram of the module). Pin functions of the IC
are given in Table 1.
During sound recording, sound is picked up by the
microphone. A microphone pre-amplifier amplifies the
voltage signal from the microphone. An AGC circuit is
included in the pre-amplifier, the extent of which is
controlled by an external capacitor and resistor. If the
voltage level of a sound signal is around 100 mV peakto-
peak, the signal can be fed directly into the IC
through ANA IN pin (pin 20). The sound signal passes
through a filter and a sampling and hold circuit. The
analogue voltage is then written into non-volatile flash
analogue RAMs.
APR9600 module
The circuit diagram of the module is shown in Figure 2. The module consists of an APR9600 chip,
an electret microphone, support components, a mode selection switch (-RE,MSEL1, MSEL2 and –
M8) and 9 keys (-M1 to –M8 and CE). The oscillation resistor is chosen so that the total recording
period is 60 seconds with a sampling rate of 4.2 kHz. Users can change the value of the ROSC to
obtain other sampling frequencies. It should be noted that if the sampling rate is increased, the
length of recording time is decreased. Table 3 gives the details.
An 8-16 Ohm speaker is to be used with the module. Users can select different modes using the
mode selection switch. The module is measured 80mm´55mm.
and experimental board
[attachment=45886]
APR9600 is a low-cost high performance sound record/replay IC incorporating flash analogue
storage technique. Recorded sound is retained even after power supply is removed from the
module. The replayed sound exhibits high quality with a low noise level. Sampling rate for a 60
second recording period is 4.2 kHz that gives a sound record/replay bandwidth of 20Hz to 2.1 kHz.
However, by changing an oscillation resistor, a sampling rate as high as 8.0 kHz can be achieved.
This shortens the total length of sound recording to 32 seconds.
Total sound recording time can be varied from 32 seconds to 60 seconds by changing the value of a
single resistor. The IC can operate in one of two modes: serial mode and parallel mode.
In serial access mode, sound can be recorded in 256 sections. In parallel access mode, sound can be
recorded in 2, 4 or 8 sections. The IC can be controlled simply using push button keys. It is also
possible to control the IC using external digital circuitry such as micro-controllers and computers.
The APR9600 has a 28 pin DIP package. Supply voltage is between 4.5V to 6.5V. During
recording and replaying, current consumption is 25 mA. In idle mode, the current drops to 1 mA.
The APR9600 experimental board is an assembled PCB board consisting of an APR9600 IC, an
electret microphone, support components and necessary switches to allow users to explore all
functions of the APR9600 chip. The oscillation resistor is chosen so that the total recording period
is 60 seconds with a sampling rate of 4.2 kHz. The board measures 80mm by 55mm.
APR9600
Pin-out of the APR9600 is given in Figure 1. A typical
connection of the chip is given in Figure 2 (This is the
circuit diagram of the module). Pin functions of the IC
are given in Table 1.
During sound recording, sound is picked up by the
microphone. A microphone pre-amplifier amplifies the
voltage signal from the microphone. An AGC circuit is
included in the pre-amplifier, the extent of which is
controlled by an external capacitor and resistor. If the
voltage level of a sound signal is around 100 mV peakto-
peak, the signal can be fed directly into the IC
through ANA IN pin (pin 20). The sound signal passes
through a filter and a sampling and hold circuit. The
analogue voltage is then written into non-volatile flash
analogue RAMs.
APR9600 module
The circuit diagram of the module is shown in Figure 2. The module consists of an APR9600 chip,
an electret microphone, support components, a mode selection switch (-RE,MSEL1, MSEL2 and –
M8) and 9 keys (-M1 to –M8 and CE). The oscillation resistor is chosen so that the total recording
period is 60 seconds with a sampling rate of 4.2 kHz. Users can change the value of the ROSC to
obtain other sampling frequencies. It should be noted that if the sampling rate is increased, the
length of recording time is decreased. Table 3 gives the details.
An 8-16 Ohm speaker is to be used with the module. Users can select different modes using the
mode selection switch. The module is measured 80mm´55mm.