a
FEATURES
Monolithic 14-Bit, 10 MSPS A/D Converter
Low Power Dissipation: 285 mW
Single +5 V Supply
Integral Nonlinearity Error: 2.5 LSB
Differential Nonlinearity Error: 0.6 LSB
Input Referred Noise: 0.36 LSB
Complete: On-Chip Sample-and-Hold Amplifier and
Voltage Reference
Signal-to-Noise and Distortion Ratio: 77.5 dB
Spurious-Free Dynamic Range: 90 dB
Out-of-Range Indicator
Straight Binary Output Data
44-Lead MQFP
VINA
VINB
CML
CAPT
CAPB
VREF
SENSE
Complete 14-Bit, 10 MSPS
Monolithic A/D Converter
AD9240
FUNCTIONAL BLOCK DIAGRAM
CLK
SHA
MDAC1
GAIN = 16
MDAC2
GAIN = 8
A/D
MDAC3
GAIN = 8
A/D
AVDD
DVDD
DRVDD
BIAS
A/D
5
A/D
4
4
5
4
4
4
DIGITAL CORRECTION LOGIC
14
OUTPUT BUFFERS
MODE
SELECT
1V
OTR
BIT 1
(MSB)
AD9240
REFCOM
AVSS
DVSS
DRVSS
BIT 14
(LSB)
PRODUCT DESCRIPTION
PRODUCT HIGHLIGHTS
The AD9240 is a 10 MSPS, single supply, 14-bit analog-to-
digital converter (ADC). It combines a low cost, high speed
CMOS process and a novel architecture to achieve the resolution
and speed of existing hybrid implementations at a fraction of the
power consumption and cost. It is a complete, monolithic ADC
with an on-chip, high performance, low noise sample-and-hold
amplifier and programmable voltage reference. An external refer-
ence can also be chosen to suit the dc accuracy and temperature
drift requirements of the application. The device uses a multistage
differential pipelined architecture with digital output error correc-
tion logic to guarantee no missing codes over the full operating
temperature range.
The input of the AD9240 is highly flexible, allowing for easy
interfacing to imaging, communications, medical and data-
acquisition systems. A truly differential input structure allows
for both single-ended and differential input interfaces of varying
input spans. The sample-and-hold amplifier (SHA) is equally
suited for multiplexed systems that switch full-scale voltage
levels in successive channels as well as sampling single-channel
inputs at frequencies up to and beyond the Nyquist rate. The
AD9240 also performs well in communication systems employ-
ing Direct-IF Down Conversion, since the SHA in the differen-
tial input mode can achieve excellent dynamic performance well
beyond its specified Nyquist frequency of 5 MHz.
A single clock input is used to control all internal conversion
cycles. The digital output data is presented in straight binary
output format. An out-of-range (OTR) signal indicates an
overflow condition which can be used with the most significant
bit to determine low or high overflow.
The AD9240 offers a complete single-chip sampling 14-bit,
analog-to-digital conversion function in a 44-lead Metric Quad
Flatpack.
Low Power and Single Supply
The AD9240 consumes only 280 mW on a single +5 V power
supply.
Excellent DC Performance Over Temperature
The AD9240 provides no missing codes, and excellent tempera-
ture drift performance over the full operating temperature range.
Excellent AC Performance and Low Noise
The AD9240 provides nearly 13 ENOB performance and has an
input referred noise of 0.36 LSB rms.
Flexible Analog Input Range
The versatile onboard sample-and-hold (SHA) can be configured
for either single ended or differential inputs of varying input spans.
Flexible Digital Outputs
The digital outputs can be configured to interface with +3 V and
+5 V CMOS logic families.
Excellent Undersampling Performance
The full power bandwidth and dynamic range of the AD9240
make it well suited for Direct-IF Down Conversion extending to
45 MHz.
REV. A
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 1998
AD [ ANALOG DEVICES ]
