ADC122S051
2 Channel, 500 kSPS 12-Bit A/D Converter
General Description
The ADC122S051 is a low-power, two-channel CMOS 12-bit
analog-to-digital converter with a high-speed serial interface.
Unlike the conventional practice of specifying performance
at a single sample rate only, the ADC122S051 is fully speci-
fied over a sample rate range of 200 kSPS to 500 kSPS. The
converter is based on a successive-approximation register
architecture with an internal track-and-hold circuit. It can be
configured to accept one or two input signals at inputs IN1
and IN2.
The output serial data is straight binary, and is compatible
with several standards, such as SPI™, QSPI™, MICROW-
IRE, and many common DSP serial interfaces.
The ADC122S051 operates with a single supply that can
range from +2.7V to +5.25V. Normal power consumption
using a +3V or +5V supply is 3.0 mW and 10 mW, respec-
tively. The power-down feature reduces the power consump-
tion to just 0.14 µW using a +3V supply, or 0.32 µW using a
+5V supply.
The ADC122S051 is packaged in an 8-lead MSOP package.
Operation over the industrial temperature range of −40˚C to
+85˚C is guaranteed.
Features
n Specified over a range of sample rates.
n Two input channels
n Variable power management
n Single power supply with 2.7V - 5.25V range
Key Specifications
n DNL +0.7 / −0.4 LSB (typ)
n INL ± 0.50 LSB (typ)
n SNR 72.5 dB (typ)
n Power Consumption
— 3V Supply 3.0 mW (typ)
— 5V Supply 10 mW (typ)
Applications
n Portable Systems
n Remote Data Acquisition
n Instrumentation and Control Systems
Pin-Compatible Alternatives by Resolution and Speed
All devices are fully pin and function compatible.
Resolution Specified for Sample Rate Range of:
50 to 200 kSPS 200 to 500 kSPS 500 kSPS to 1 MSPS
12-bit ADC122S021 ADC122S051 ADC122S101
10-bit ADC102S021 ADC102S051 ADC102S101
8-bit ADC082S021 ADC082S051 ADC082S101
Connection Diagram
20106405
Ordering Information
Order Code Temperature Range Description Top Mark
ADC122S051CIMM −40˚C to +85˚C 8-Lead MSOP Package X06C
ADC122S051CIMMX −40˚C to +85˚C 8-Lead MSOP Package, Tape & Reel X06C
ADC122S051EVAL Evaluation Board
TRI-STATE
®
is a trademark of National Semiconductor Corporation
QSPI™ and SPI™ are trademarks of Motorola, Inc.
April 2005
ADC122S051
2
Channel,
500
kSPS
12-Bit
A/D
Converter
© 2005 National Semiconductor Corporation DS201064 www.national.com