CALIFORNIA MICRO DEVICES
CM8888/8888-2
CMOS INTEGRATED DTMF TRANSCEIVER
Features
Advanced CMOS technology for low power
consumption and increased noise immunity
Complete DTMF
Transmitter/Receiver
Standard 8051, 8086/8 microprocessor port
Central office quality and performance
Adjustable guard time
Automatic tone burst mode
Call progress mode
Single +5 volt power supply
20-pin DIP, 20-pin DIP EIAJ, 20-pin SOIC,
28-pin PLCC packages
2 MHz microprocessor port operation
Applications
Paging systems
Repeater systems/mobile radio
Interconnect dialers
PABX systems
Computer systems
Fax machines
Pay telephones
Credit card verification
Contact factory for complete data sheet.
Product Description
The CMD CM8888/8888-2 is a fully integrated DTMF Transceiver, featuring adjustable guard time, automatic tone burst
mode, call progress mode, and a fully compatible 8051, 8086/8 microprocessor interface. The CM8888/8888-2 is
manufactured using state-of-the-art advanced CMOS technology for low power consumption and precise data
handling. The CM8888/8888-2 is based on the industry standard CM8870 DTMF Receiver, while the transmitter utilizes
a switched-capacitor D/A converter for low distortion, highly accurate DTMF signaling. Internal counters provide an
automatic tone burst mode which allows tone bursts to be transmitted with precise timing. A call progress filter can
be selected by an external microprocessor for analyzing call progress tones. The CM8888-2 is electrically equivalent to
the CM8888 but does not include the call progress function.
Block Diagram
© 1987, 1996 CMD Corp. All rights reserved.
8/96
215 Topaz Street, Milpitas, California 95035
Tel: (408) 263-3214
Fax: (408) 263-7846
CALIFORNIA MICRO DEVICES
CM8888/8888-2
Pin Assignments
StGT
27
VDD
ESt
26
IN+
1
GS
NC
3
CM8888
IN+
IN-
GS
VREF
VSS
OSC1
OSC2
TONE
WR
CS
1
2
3
4
5
6
7
8
9
10
20
19
18
VDD
StGT
ESt
D3
D2
D1
D0
IRQ/CP
RD
RS0
VSS
OSC1
OSC2
NC
NC
7
8
9
10
11
NC
VREF
5
6
4
2
IN-
28
25
24
23
NC
NC
NC
D3
D2
D1
D0
CM8888/8888-2
17
16
15
14
13
12
11
CM8888
CM8888/8888-2
22
21
20
19
12
13
14
15
16
17
RD
TONE
WR
CS
RS0
NC
Ordering Information
Example:
CM8888/-2
P
I
Product Identification Number
CM8888 Call Progress Mode
CM8888-2 Without Call Progress Mode
Package
P Plastic DIP (20)
F Plastic DIP EIAJ (20)
PE PLCC (28)
S SOIC (20)
Temperature/Processing
I
-40
O
C to +85
O
C, ±5% P.S. Tol.
© 1987, 1996 CMD Corp. All rights reserved.
215 Topaz Street, Milpitas, California 95035
Tel: (408) 263-3214
Fax: (408) 263-7846
IRQ/CP
18
8/96
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