ADS8508_14 Datasheet, PDF (1/28 Pages) Texas Instruments – 12-BIT 250-KSPS SERIAL CMOS SAMPLING ANALOG-TO-DIGITAL CONVERTER

BurrĆBrown Products
from Texas Instruments
ADS8508
SLAS433 – SEPTEMBER 2005
12-BIT 250-KSPS SERIAL CMOS SAMPLING ANALOG-TO-DIGITAL CONVERTER
FEATURES
• 250-kHz Sampling Rate
• 4-V, 5-V, 10-V, ±3.33-V, ±5-V, and ±10-V Input
Ranges
• 73-dB SINAD With 45-kHz Input
• ±0.45 LSB Max INL
• ±0.45 LSB Max DNL, 12-Bits No Missing
Codes
• ±1 LSB Bipolar Zero Errors
• ±0.4 PPM/°C Bipolar Zero Error Drift
• Six Specified Input Ranges
• SPI Compatible Serial Output with
Daisy-Chain (TAG) Feature
• 5-V Supply
• Pin-Compatible With ADS7808 (Low Speed)
and 16-Bit ADS8509/7809
• Uses Internal or External Reference
• 70-mW Typ Power Dissipation at 250 KSPS
• 20-Pin SO Package
• Simple DSP Interface
APPLICATIONS
• Industrial Process Control
• Data Acquisition Systems
• Digital Signal Processing
• Medical Equipment
• Instrumentation
DESCRIPTION
The ADS8508 is a complete 12-bit sampling
analog-to-digital (A/D) converter using state-of-the-art
CMOS structures. It contains a complete 12-bit,
capacitor-based, successive approximation register
(SAR) A/D converter with sample-and-hold, refer-
ence, clock, and a serial data interface. Data can be
output using the internal clock or can be
synchronized to an external data clock. The ADS8508
also provides an output synchronization pulse for
ease of use with standard DSP processors.
The ADS8508 is specified at a 250-kHz sampling rate
over the full temperature range. Precision resistors
provide various input ranges including ±10 V and 0 V
to 5 V, while the innovative design allows operation
from a single +5-V supply with power dissipation
under 100 mW.
The ADS8508 is available in a 20-pin SO package,
fully specified for operation over the industrial -40°C
to 85°C temperature range.
Successive Approximation Register
Clock EXT/INT
R1_IN
R2_IN
R3_IN
9.8 kΩ
4.9 kΩ
2.5 kΩ
CAP
REF
CDAC
10 kΩ
Buffer
4 kΩ
Internal
+2.5 V Ref
Comparator
Serial
Data
Out
&
Control
BUSY
DATACLK
DATA
R/C
SB/BTC
CS
PWRD
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005, Texas Instruments Incorporated