Integrated Silicon Solution, Inc. -- 1-800-379-4774
1
Rev. D
02/25/00
ISSI reserves the right to make changes to its products at any time without notice in order to improve design and supply the best possible product. We assume no responsibility for any
errors which may appear in this publication. Copyright 2000, Integrated Silicon Solution, Inc.
IS22C040
ISSI
32 to 40 SEC INSTANT VOICE ROM
FEATURES
Voice length at
8 KHz sampling is 32 seconds
6 KHz sampling is 40 seconds
Silence compression to save memory
Eight trigger pins, S1 to S8 for 32 sections
SBT pin play-all or sequential play-all
15 ms debounce time suitable for CDS
IRP interrupt pin stops playback at once
STP stop pulse generated at end of playback
BUSY signal for CPU control
Two LEDs flash at 3 Hz interval
3.0V to 6V single power supply operation
Low standby current (<5 A at 3V)
Auto-power down
Built-in oscillator, D/A converter, EPROM
ADPCM data compression
Optional pop noise elimination function
C
OUT
pin drives speaker with a transistor
Development tools support
V
OUT
1 and V
OUT
2 drives buzzer directly
Sampling rate determined by external resistor
Holdable and unholdable triggering option
Industrial temperature available
GENERAL DESCRIPTION
IS22C040 is a high-quality voice synthesizer with a
capacity of 32 to 40 seconds. A proprietary ADPCM
algorithm is used. The audio message is stored in a 1024-
Kbit on-chip EPROM.
The IS22C040 eliminates the need of complicated circuitry
in voice playback (Figure 1) but still achieves high voice
quality. Sounds such as human speech, animal sounds,
musical sounds, and even special sound effects can be
synthesized. Devices can be cascaded to achieve longer
voice duration (Figure 3). Two devices can be configured
in parallel (Figure 4) in order to achieve signal mixing
without an external mixer allowing speeches to be mixed
with background music synthesis from two different chips.
The instant programming nature of the IS22C040 allows a
very short production turnaround time. There are no NRE
charges that are usually required with conventional voice
ROMs. Users now can apply a voice synthesis function as
an additional feature to their products even when production
volume is relatively small. It is also ideal for trial or
engineering prototyping. As a result, the initial investment
is minimal and the risk in the product development phase
is reduced.
The IS22C040 provides a wide voltage operating range
from 3.0V to 6.0V. A pair of PWM output pins, V
OUT
1 and
V
OUT
2 provide direct drive to a buzzer (Figure 2). Voice
quality from a buzzer is comparable to speaker output and
power consumption is much lower.
A current output pin, C
OUT
, enables the device to drive a
speaker with a low cost NPN transistor. No complex
filtering or amplifier circuit is needed. An automatic ramp
up/down function eliminates the undesired noise at the
end of playback.
Up to 32 sections are accessible through S1 to S8. The
SBT trigger pin can be programmed to playback all 32
sections or sequentially from section 1 to 32. An interrupt
pin (IRP) and stop pulse (STP) or BUSY signals provide
handshaking with microprocessors or other IS22C040
devices. All trigger pins give 15 ms debounce time and is
ideal for CDS applications as in Figure 6. Two LED drivers
are available, flashing on and off at approximately 3Hz
intervals (Figure 5). The internal voltage compensation
oscillator requires only one external resistor. Different
sampling frequencies are determined by the external
oscillator resistor value.
FEBRUARY 2000
2
Integrated Silicon Solution, Inc. -- 1-800-379-4774
Rev. D
02/25/00
IS22C040
ISSI
Programmable Options
The IS22C040 provides different control functions for
user specified applications. They include:
Non-sequential or Sequential Play-all
Unholdable or Holdable trigger
STOP or BUSY signal selection
Automatic ramp-up/ramp-down or no ramp-up/ramp-down
OSCILLATOR
OSC
CLOCK
GENERATOR
CONTROL
LOGIC
S1
S8
SBT
IRP
LED
DRIVER
LED2
LED1
STP
POP NOISE
REDUCTION
ADDRESS
SEQUENCER
VOICE
EPROM
ADPCM
DECODER
BUZZER
BUFFER
D/A
C
OUT
V
OUT1
V
OUT2
GND
Vcc
BLOCK DIAGRAM
Silence Compression
If a particular sound sequence includes periods of silence,
the IS22C040 will automatically compress the silence to
save memory space. This compression will not affect
playback of the sound sequence.
4
Integrated Silicon Solution, Inc. -- 1-800-379-4774
Rev. D
02/25/00
IS22C040
ISSI
PIN DESCRIPTIONS
Name
I/O
Function
S8
I
Trigger Switch 8, Internal Pull
LOW, Active HIGH
LED1
O
Drives First LED Flash at 3 Hz,
Active LOW
V
OUT1
O
PWM Audio Signal Output for
Buzzer
V
OUT2
O
Compliment PWM Audio Signal
Output for Buzzer
GND
--
Power Ground
STP/BUSY
O
Generate 30 ms Pulse or Busy
Signal After Voice Playback
LED2
O
Drives Second LED Flash at 3 Hz,
Active LOW
C
OUT
O
Current Output from Internal
DAC for Speaker Playback
OSC
I
Oscillator Resistor Pin to
Control Sampling Frequency
S5
I
Trigger Switch 5, Internal Pull
LOW, Active HIGH
Note:
1. The following pins are used to program data into the memory on the chip: pins 5, 6, 7, 9, 12, 15, 18 and 19.
PIN CONFIGURATION
20-Pin 300-mil PDIP
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
S8
LED1
V
OUT1
V
OUT2
GND
STP
LED2
C
OUT
OSC
S5
S7
IRP
SBT
S4
S3
V
CC
S2
S1
V
PP
S6
Name
I/O
Function
S6
I
Trigger Switch 6, Internal Pull
LOW, Active HIGH
V
PP
--
Program Power Supply, No
Connect When Voice Playback
S1
I
Trigger Switch 1, Internal Pull
LOW, Active HIGH
S2
I
Trigger Switch 2, Internal Pull
LOW, Active HIGH
V
CC
--
Positive Power Supply
S3
I
Trigger Switch 3, Internal Pull
LOW, Active HIGH
S4
I
Trigger Switch 4, Internal Pull
LOW, Active HIGH
SBT
I
One Key or Sequential Trigger,
Internal Pull LOW, Active HIGH
IRP
I
Interrupt to Stop Playback, Internal
Pull LOW, Active HIGH
S7
I
Trigger Switch 7, Internal Pull
LOW, Active HIGH