®
ADS
7808
ADS7808
ADS
7808
12-Bit 10
µ
s Serial CMOS Sampling
ANALOG-to-DIGITAL CONVERTER
FEATURES
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100kHz SAMPLING RATE
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72dB SINAD WITH 45kHz INPUT
±
1/2 LSB INL AND DNL
SIX SPECIFIED INPUT RANGES
SERIAL OUTPUT
SINGLE +5V SUPPLY OPERATION
PIN-COMPATIBLE WITH 16-BIT ADS7809
DESCRIPTION
The ADS7808 is a complete 12-bit sampling analog-
to-digital using state-of-the-art CMOS structures. It
contains a 12-bit capacitor-based SAR A/D with S/H,
reference, clock, and a serial data interface. Data can
be output using the internal clock, or can be synchro-
nized to an external data clock. The ADS7808 also
provides an output synchronization pulse for ease of
use with standard DSP processors.
The ADS7808 is specified at a 100kHz sampling rate,
and guaranteed over the full temperature range. Laser-
trimmed scaling resistors provide various input ranges
including
±10V
and 0V to 5V, while an innovative
design operates from a single +5V supply, with power
dissipation under 100mW.
The 20-pin ADS7808 is available in a plastic 0.3" DIP
and in an SOIC, both fully specified for operation over
the industrial –40°C to +85°C range.
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USES INTERNAL OR EXTERNAL
REFERENCE
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100mW MAX POWER DISSIPATION
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20-PIN 0.3" PLASTIC DIP AND SOIC
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SIMPLE DSP INTERFACE
R/C
CS
Power Down
Successive Approximation Register and Control Logic
Clock
20kΩ
R1
IN
10kΩ
R2
IN
20kΩ
5kΩ
R3
IN
CAP
Buffer
4kΩ
REF
Internal
+2.5V Ref
Comparator
Serial
Data
Out
Serial Data
Data Clock
BUSY
CDAC
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111
Internet: http://www.burr-brown.com/ • FAXLine: (800) 548-6133 (US/Canada Only) • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
®
©
1992 Burr-Brown Corporation
PDS-1155B
1
ADS7808
Printed in U.S.A. January 1997