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ADS7884
ADS7885
SLAS567–MARCH 2008
10-/8-BIT, 3-MSPS, MICRO-POWER, MINIATURE
SAR ANALOG-TO-DIGITAL CONVERTERS
1
FEATURES
APPLICATIONS
•
•
•
Base Band Converters in Radio
Communication
Motor Current/Bus Voltage Sensors in Digital
Drives
Optical Networking (DWDM, MEMS Based
Switching)
Optical Sensors
Battery Powered Systems
Medical Instrumentations
High-Speed Data Acquisition Systems
High-Speed Closed-Loop Systems
•
•
•
•
•
•
•
3-MHz Sample Rate Serial Device
10-Bit Resolution – ADS7884
8-Bit Resolution – ADS7885
Zero Latency
48-MHz Serial Interface
Supply Range: 2.7 V to 5.5 V
Low Power Dissipation:
•
•
•
•
•
–
–
6.8 mW at 3-V VDD, 2.5 MSPS
15 mw at 5-V VDD, 3 MSPS
•
•
•
•
•
•
•
•
±0.3 LSB INL, ±0.3 LSB DNL – ADS7884
±0.15 LSB INL, ±0.1 LSB DNL – ADS7885
61.7 dB SINAD, –81 dB THD – ADS7884
49.8 dB SINAD, –68 dB THD – ADS7885
Unipolar Input Range: 0 V to VDD
Powerdown Current: 1 µA
Wide Input Bandwidth: 30 MHz at 3 dB
6-Pin SOT23 Package
DESCRIPTION
The ADS7884 is a 10-bit, 3-MSPS analog-to-digital converter (ADC), and the ADS7885 is a 8-bit, 3-MSPS ADC.
The devices include a capacitor based SAR A/D converter with inherent sample and hold. The serial interface in
each device is controlled by the CS and SCLK signals for glueless connections with microprocessors and DSPs.
The input signal is sampled with the falling edge of CS, and SCLK is used for conversion and serial data output.
The devices operate from a wide supply range from 2.7 V to 5.5 V. The low power consumption of the devices
make them suitable for battery-powered applications. The devices also include a power saving powerdown
feature for when the devices are operated at lower conversion speeds.
The high level of the digital input to the device is not limited to device VDD. This means the digital input can go as
high as 5.5 V when device supply is 2.7 V. This feature is useful when digital signals are coming from other
circuit with different supply levels. Also this relaxes restriction on power up sequencing.
The ADS7884 and ADS7885 are available in a 6-pin SOT23 package and are specified for operation from –40°C
to 125°C.
Micro-Power Miniature SAR Converter Family
BIT
12-Bit
< 300 KSPS
ADS7866 (1.2 VDD to 3.6 VDD
ADS7867 (1.2 VDD to 3.6 VDD
ADS7868 (1.2 VDD to 3.6 VDD
300 KSPS – 1.25 MSPS
3 MSPS
)
)
)
ADS7886 (2.35 VDD to 5.25 VDD
ADS7887 (2.35 VDD to 5.25 VDD
ADS7888 (2.35 VDD to 5.25 VDD
)
)
)
—
10-Bit
8-Bit
ADS7884 (2.7 VDD to 5.5 VDD
)
)
ADS7885 (2.7 VDD to 5.5 VDD
1
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 © 2008, Texas Instruments Incorporated