Burr Brown Products
from Texas Instruments
ADS1208
SBAS348A – MARCH 2005 – REVISED MARCH 2005
2nd-Order Delta-Sigma Modulator
with Excitation for Hall Elements
FEATURES
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±100mV Specified Input Range
±125mV Full-Scale Range
95dB typ. CMR, 82dB typ. SNR
Adjustable Current Output for Sensor Biasing
Digital Output Compatible to ADS1202/03
Differential Digital Outputs
Separate 2.7V to 5.5V Digital Supply Pin
DESCRIPTION
The ADS1208 is a 2nd-order
∆Σ
(delta-sigma) modu-
lator operating at a 10MHz clock rate. The specified
input range is ±100mV, optimized for current
measurement with a Hall sensor, especially in motor
control applications. The ADS1208 contains a
programmable current source for sensor biasing and
has integrated input buffers for fast settling of the
sample capacitors; it also requires only a minimum of
external components. The differential analog input
offers low noise and excellent common-mode rejec-
tion.
APPLICATIONS
Motor Control
Current Measurement
Hall Sensors
Bridge Sensors
Instrumentation
AVDD
AVDD
BVDD
ADS1208
IADJ
IOUT
Buffer
Internal 2.5V
Reference
REFOUT
REFIN
Buffer
V
IN+
Buffer
2nd−
Order
∆Σ
Modulator
MDATA
MDATA
MCLK
MCLK
V
IN−
Buffer
Interface
Circuit
RC Oscillator
20MHz
M0
M1
BGND
AGND
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
BURR-BROWN [ BURR-BROWN CORPORATION ]
