CSP1027 Datasheet, PDF (1/64 Pages) Agere Systems – CSP1027 Voice Band Codec for Cellular Handset and Modem Applications

Data Sheet
December 1999
CSP1027 Voice Band Codec for
Cellular Handset and Modem Applications
1 Features
s ∆-Σ (delta-sigma) A/D and D/A converters with stan-
dard 16-bit serial I/O interface.
s On-chip filters meet ITU-T G.712 voice band fre-
quency response and signal to distortion plus noise
specifications. Suitable for IS-54, GSM, and JDC dig-
ital cellular applications.
s Low-profile package (<1.5 mm) 48-pin thin quad flat
pack (TQFP) available or 44-pin EIAJ quad flat pack
(QFP).
s Operates in systems with a 3.0 V to 5.0 V digital
power supply and a 5.0 V analog supply.
s Low-power 0.9 µm CMOS technology, fully static
design, typical power of 68 mW when active and
0.05 mW in standby with a 3.3 V digital supply and a
5.0 V analog supply.
s A low-power inactive (standby) state without stopping
clock or removing power supply.
s Sampling rates up to 24 kHz.
s On-chip programmable sampling clock generator
allows input clock to be an integer multiple of
125 times the sampling rate or an integer multiple of
the sampling rate.
s Programmable phase adjust of both codec sampling
clock and baseband codec clock.
s Two on-chip clock dividers for generating the output
clock for the baseband codec and the output clock
for other processors.
s Regulated microphone power supply.
s Microphone preamplifier, with programmable input
ranges of 0.16 Vp and 0.5 Vp.
s Output amplifier, with programmable gain settings,
0 dB to –45 dB in –3 dB steps.
s High-pass filters selectable via control registers.
s Power-on reset pulse generator.
s Standard 16-bit serial I/O interface.
s Serial I/O multiprocessor mode compatible with the
Lucent Technologies Microelectronics Group’s
DSP16A and DSP1610/1616/1617/1618 Digital Sig-
nal Processors.
2 Description
The Lucent CSP1027 is a high-precision linear voice-
band ∆-Σ (delta-sigma) codec designed for cellular
handset and modem applications. The device is fabri-
cated in low-power CMOS technology and designed for
low-voltage (3.0 V to 5.0 V) digital systems. The
CSP1027 is packaged in a 44-pin EIAJ quad flat pack
(QFP) or a 48-pin EIAJ thin quad flat pack (TQFP). In
the 48-pin TQFP, the CSP1027 occupies a total volume
of 0.0784 cm³.
The CSP1027 has a variety of significant programma-
ble features not found in standard voice band codecs.
The analog interface includes a microphone preampli-
fier with programmable gain settings, an output ampli-
fier with gain programmable in 3 dB steps over a 45 dB
range, and a regulated microphone power supply. An
inactive mode allows a low-power standby state, and a
mute function provides suppression of the analog out-
put. On-chip antialiasing and anti-imaging filtering
includes a selectable high-pass filter. The CSP1027
meets ITU-T G.712 voice band specifications.
The programmable features of the CSP1027 are set by
writing four on-chip control registers through the serial
I/O interface. The codec’s digital input/output uses a
linear 16-bit two’s complement data format that is also
transferred through the serial I/O interface. The
CSP1027 interfaces easily to the 16-bit serial ports of
digital signal processors and other devices. The serial
interface supports the Lucent fixed-point DSP family
serial multiprocessor mode. This allows up to eight
compatible devices, including two CSP1027s, to inter-
face to each other on a common 4-wire bus using a
time-division-multiplexing scheme.