ADC122S706_14 Datasheet, PDF (1/31 Pages) Texas Instruments – Dual 12-Bit, 500 kSPS to 1 MSPS, Simultaneous Sampling A/D Converter

ADC122S706
www.ti.com
SNAS408 – NOVEMBER 2007
ADC122S706 Dual 12-Bit, 500 kSPS to 1 MSPS, Simultaneous Sampling A/D Converter
Check for Samples: ADC122S706
FEATURES
1
•2 True Simultaneous Sampling Differential
Inputs
• Guaranteed performance from 500 kSPS to 1
MSPS
• External Reference
• Wide Input Common-Mode Voltage Range
• Single or Dual High-Speed Serial Data Outputs
• Operating Temperature Range of −40°C to
+105°C
• SPI™/QSPI™/MICROWIRE™/DSP compatible
Serial Interface
APPLICATIONS
• Motor Control
• Power Meters/Monitors
• Multi-Axis Positioning Systems
• Instrumentation and Control Systems
• Data Acquisition Systems
• Medical Instruments
• Direct Sensor Interface
DESCRIPTION
The ADC122S706 is a dual 12-bit, 500 kSPS to 1 MSPS simultaneous sampling Analog-to-Digital (A/D)
converter. The analog inputs on both channels are sampled simultaneously to preserve their relative phase
information to each other. The converter is based on a successive-approximation register architecture where the
differential nature of the analog inputs is maintained from the internal track-and-hold circuits throughout the A/D
converter to provide excellent common-mode signal rejection. The ADC122S706 features an external reference
that can be varied from 1.0V to V_A.
The ADC122S706 offers dual high-speed serial data outputs that are binary 2's complement and are compatible
with several standards, such as SPI™, QSPI™, MICROWIRE™, and many common DSP serial interfaces.
Channel A's conversion result is outputted on D_OUTA while Channel B's conversion result is outputted on D_OUTB.
This feature makes the ADC122S706 an excellent replacement for systems using two distinct ADCs in a
simultaneous sampling application. The serial clock (SCLK) and chip select bar (CS) are shared by both
channels. For lower power consumption, a single serial data output mode is externally selectable.
The ADC122S706 may be operated with independent analog (V_A) and digital (V_D) supplies. V_A can range from
4.5V to 5.5V and V_D can range from 2.7V to V_A. With the ADC122S706 operating with a V_A of 5V and a V_D of 3V,
the power consumption at 1 MSPS is typically 25 mW. Operating in power-down mode, the power consumption
of the ADC122S706 decreases to 3 µW. The differential input, low power consumption, and small size make the
ADC122S706 ideal for direct connection to sensors in motor control applications.
Operation is guaranteed over the industrial temperature range of −40°C to +105°C and clock rates of 8 MHz to
16 MHz. The ADC122S706 is available in a 14-lead TSSOP package.
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
Table 1. Key Specifications
VALUE
UNIT
Conversion Rate
500 kSPS to
1 MSPS
INL
±1
LSB (max)
DNL
±0.95
LSB (max)
SNR
71
dBc (min)
THD
-72
dBc (min)
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.
All trademarks are the property of their respective owners.
2
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 © 2007, Texas Instruments Incorporated