ADS7887_14 Datasheet, PDF (1/29 Pages) Texas Instruments – 10-/8-Bit, 1.25-MSPS, MICRO-POWER, MINIATURE SAR ANALOG-TO-DIGITAL CONVERTERS

BurrĆBrown Products
from Texas Instruments
10-/8-Bit, 1.25-MSPS, MICRO-POWER, MINIATURE
SAR ANALOG-TO-DIGITAL CONVERTERS
ADS7887
ADS7888
SLAS468 – JUNE 2005
FEATURES
• 1.25-MHz Sample Rate Serial Device
• 10-Bit Resolution – ADS7887
• 8-Bit Resolution – ADS7888
• Zero Latency
• 25-MHz Serial Interface
• Supply Range: 2.35 V to 5.25 V
• Typical Power Dissipation at 1.25 MSPS:
– 3.8 mW at 3-V V_DD
– 8 mw at 5-V V_DD
• ±0.35 LSB INL, DNL – ADS7887
• ±0.15 LSB INL, ±0.1 LSB DNL – ADS7888
• 61dB SINAD, -84 dB THD – ADSA7887
• 49.5 dB SINAD, -67.5 dB THD – ADS7888
• Unipolar Input Range: 0 V to V_DD
• Power Down Current: 1 µA
• Wide Input Bandwidth: 15 MHz at 3 dB
• 6-Pin SOT23 and SC70 Packages
APPLICATIONS
• Base Band Converters in Radio Communi-
cation
• 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
DESCRIPTION
The ADS7887 is a 10-bit, 1.25-MSPS analog-to-digital converter (ADC), and the ADS7888 is a 8-bit, 1.25-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 2.35 V to 5.25 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 V_DD. This means the digital input can go as
high as 5.25 V when device supply is 2.35 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 ADS7887 and ADS7888 are available in 6-pin SOT23 and SC70 packages and are specified for operation
from -40°C to 125°C.
BIT
12-Bit
10-Bit
8-Bit
Micro-Power Miniature SAR Converter Family
< 300 KSPS
ADS7866 (1.2 V_DD to 3.6 V_DD)
ADS7867 (1.2 V_DD to 3.6 V_DD)
ADS7868 (1.2 V_DD to 3.6 V_DD)
300 KSPS – 1.25 MSPS
ADS7886 (2.35 V_DD to 5.25 V_DD)
ADS7887 (2.35 V_DD to 5.25 V_DD)
ADS7888 (2.35 V_DD to 5.25 V_DD)
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