DS2165Q
16/24/32kbps ADPCM Processor
www.maxim-ic.com
FEATURES
PIN ASSIGNMENT (Top View)
C Compresses/expands 64kbps PCM voice
to/from either 32kbps, 24kbps, or 16kbps
C Dual fully independent channel architecture;
device can be programmed to perform either:
ꢀ two expansions
4
3
2
1
28 27 26
25
5
6
7
8
NC
A0
A1
FSY
YOUT
CS
24
23
ꢀ two compressions
22
21
20
19
DS2165Q
A2
A3
A4
A5
SDI
9
SCLK
XOUT
NC
ꢀ one expansion and one compression
C Interconnects directly to combo-codec
devices
10
11
12 13 14 15 16 17 18
C Input to output delay is less than 375ꢁs
C Simple serial port used to configure the
device
28-Pin PLCC
C On-board time-slot assigner-circuit (TSAC)
function allows data to be input/output at
various time slots
C Supports Channel Associated Signaling
C Each channel can be independently idled or
placed into bypass
C Available hardware mode requires no host
processor; ideal for voice storage
applications
C Single +5V supply; low-power CMOS
technology
C Available in 28-pin PLCC
C 3V operation version is available
(DS2165QL)
DESCRIPTION
The DS2165Q ADPCM processor chip is a dedicated digital-signal-processing (DSP) chip that has been
optimized to perform adaptive-differential pulse-code modulation (ADPCM) speech compression at three
different rates. The chip can be programmed to compress (expand) 64kbps voice data down to (up from)
either 32kbps, 24kbps, or 16kbps. The compression to 32kbps follows the algorithm specified by CCITT
Recommendation G.721 (July 1986) and ANSI document T1.301 (April 1987). The compression to
24kbps follows ANSI document T1.303. The compression to 16kbps follows a proprietary algorithm
developed by Dallas Semiconductor. The DS2165Q can switch compression algorithms on-the-fly. This
allows the user to make maximum use of the available bandwidth on a dynamic basis.
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple
revisions of any device may be simultaneously available through various sales channels. For information about device errata,
click here: http://www.maxim-ic.com/errata.
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