AD9238

Features:

Integrated Dual 12-Bit Analog-to-Digital Converters
Single 3 V Supply Operation (2.7 V to 3.6 V)
SNR = 70 dBc (to Nyquist, AD9238-65)
SFDR = 85 dBc (to Nyquist, AD9238-65)
Low Power: 600 mW at 65 MSPS
Differential Input with 500 MHz 3 dB Bandwidth
On-Chip Reference and SHA
Flexible Analog Input: 1 V p-p to 2 V p-p Range
Offset Binary or Twos Complement Data Format
Clock Duty Cycle Stabilizer




Application

Ultrasound Equipment
IF Sampling in Communications Receivers: IS-95, CDMA One, IMT-2000
Battery-Powered Instruments
Hand-Held Scopemeters
Low Cost Digital Oscilloscopes




Pinout








Specifications



AVDD AGND 0.3 +3.9 V
DRVDDDRGND 0.3 +3.9 V
AGND DRGND 0.3+0.3V
AVDD DRVDD 3.9 +3.9 V








Description

The AD9238 is a dual, 3 V, 12-bit, 20 MSPS/40 MSPS/65 MSPS analog-to-digital converter. It features dual high performance sample-and-hold amplifi ers and an integrated voltage reference. The AD9238 uses a multistage differential pipelined architecture with output error correction logic to provide 12-bit accuracy and guarantee no missing codes over the full operating temperature range at data rates up to 65 MSPS.

The wide bandwidth, differential SHA allows for a variety of user selectable input ranges and offsets including single-ended applications. It is suitable for various applications including multiplexed systems that switch full-scale voltage levels in successive channels and for sampling inputs at frequencies well beyond the Nyquist rate. The AD9238 is suitable for applications in communications, imaging, and medical ultrasound.Dual single-ended clock inputs are used to control all internal conversion cycles. A duty cycle stabilizer is available on the AD9238-65 and can compensate for wide variations in the clock duty cycle, allowing the converters to maintain excellent performance. The digital output data is presented in either straight binary or twos complement format. Out-of-range signals indicate an overfl ow condition, which can be used with the most signifi cant bit to determine low or high overfl ow.Fabricated on an advanced CMOS process, the AD9238 is available in a space saving 64-lead LQFP and is specifi ed over the industrial temperature range (40°C to +85°C).