
1
Copyright
(All Rights Reserved)
Cirrus Logic, Inc.
Crystal Semiconductor Products Division
P.O. Box 17847, Austin, Texas 78760
(512) 445 7222 FAX: (512) 445 7581
http://www.crystal.com
CS5520
16-Bit/20-Bit Bridge Transducer A/D Converter
16-bit & 20-bit Bridge Transducer A/D Converters
Features
l
On-chip Instrumentation Amplifier
l
On-chip Programmable Gain Amplifier
l
On-Chip 4-Bit D/A For Offset Removal
l
Dynamic Excitation Options
l
Linearity Error: ±0.0015% FS
-
20-
b
it
,
No Missing Codes
l
CMRR at 50/60 Hz > 200 dB
l
System Calibration Capability with calibration
read/write option
l
3
-
, 4
-,
or 5
-
wire Serial Communications Port
l
Low Power Consumption: 40 mW
-
10 μW Standby Mode for Portable applications
Description
The CS5516 and CS5520 are complete solutions for dig-
itizing low level signals from strain gauges, load cells,
and pressure transducers. Any family of mV output
transducers, including those requiring bridge excitation,
can be interfaced directly to the CS5516 or CS5520. The
devices offer an on-chip software programmable instru-
mentation amplifier block, choice of DC or AC bridge
excitation, and software selectable reference and signal
demodulation.
The CS5516 uses delta-sigma modulation to achieve
16-bit resolution at output word rates up to 60
Sps
.
The
CS5520 achieves 20-bit resolution at
output
word rates
up to
60
Sps
.
The CS5516 and CS5520 sample at a rate set by the
user in the form of either an external CMOS clock or a
crystal. On-chip digital filtering provides rejection of all
frequencies above 12 Hz for a 4.096 MHz clock.
The CS5516 and CS5520 include system calibration to
null offset and gain errors in the input channel. The digi-
tal values associated with the system calibration can be
written to, or read from, the calibration RAM locations at
any time via the serial communications port. The 4-bit
DC offset D/A converter, in conjunction with digital cor-
rection, is initially used to zero the input offset value.
See page 29
.
I
$,1
$,1
95()
95()
%ULGJH
6\QF
%;
;
;
*DLQ
%ORFN
ELW'$
&RQYHUWHU
Σ
%;
9$
9$
$*1'
$*1'
&KDQQHO
'HOWD6LJPD
0RGXODWRU
,1
287
,1
287
&KDQQHO
),5
)LOWHU
&DOLEUDWLRQ
0'59
0'59
9'
9'
'*1'
;,1
;287
602'( 6&/. '5'<
&6
567
6HULDO,QWHUIDFH
÷
62'
6,'
MAR ‘95
DS74F1
DS74F2
Copyright
Cirrus Logic, Inc. 2005
CS5516
SEP ‘05