Document
ADC14L040 14-Bit, 40 MSPS, 235 mW A/D Converter
June 2005
ADC14L040 14-Bit, 40 MSPS, 235 mW A/D Converter
General Description
The ADC14L040 is a low power monolithic CMOS analogto-digital converter capable of converting analog input signals into 14-bit digital words at 40 Megasamples per second (MSPS). These converters use a differential, pipeline architecture with digital error correction and an on-chip sampleand-hold circuit to minimize power consumption while providing excellent dynamic performance and a 150 MHz Full Power Bandwidth. Operating on a single +3.3V power supply, the ADC14L040 achieves 11.9 effective bits at nyquist and consumes just 235 mW at 40 MSPS . The Power Down feature reduces power consumption to 15 mW. The differential inputs provide a full scale differential input swing equal to 2 times VREF with the possibility of a singleended input. Full use of the differential input is recommended for optimum performance. Duty cycle stabilization and output data format are selectable using a quad state function pin. The output data can be set for offset binary or two’s complement. To ease interfacing to lower voltage systems, the digital output driver power pins of the ADC14L040 can be connected to a separate supply voltage in the range of 2.4V to the analog supply voltage. This device is available in the 32-lead LQFP package and will operate over the industrial temperature range of −40˚C to +85˚C. An evaluation board is available to ease the evaluation process.
Features
n n n n n n Single +3.3V supply operation Internal sample-and-hold Internal reference Outputs 2.4V to 3.6V compatible Duty Cycle Stabilizer Power down mode
Key Specifications
n n n n n n n n Resolution DNL SNR (fIN = 10 MHz) SFDR (fIN = 10 MHz) Data Latency Power Consumption -- Operating -- Power Down Mode 14 Bits
± 0.5 LSB (typ)
74 dB (typ) 90 dB (typ) 7 Clock Cycles 235 mW (typ) 15 mW (typ)
Applications
n n n n Medical Imaging Instrumentation Communications Digital Video
w
w
w
.d
e e h s a t a
. u t4
m o c
20146501
© 2005 National Semiconductor Corporation
DS201465
www.national.com
www.DataSheet4U.com
Connection Diagram
ADC14L040
Ordering Information
Industrial (−40˚C ≤ TA ≤ +85˚C) ADC14L040CIVY ADC14L040EVAL Package 32 Pin LQFP Evaluation Board
Block Diagram
20146502
www.national.com
2
ADC14L040
Pin Descriptions and Equivalent Circuits
Pin No. ANALOG I/O Differential analog input pins. With a 1.0V reference voltage the differential full-scale input signal level is 2.0 VP-P with each input pin voltage centered on a common mode voltage, VCM. The negative input pins may be connected to VCM for single-ended operation, but a differential input signal is required for best performance. Symbol Equivalent Circuit Description
2
VIN+
3
VIN−
1
VREF
This pin is the reference select pin and the external reference input. If (VA - 0.3V) < VREF < VA, the internal 1.0V reference is selected. If AGND < VREF < (AGND + 0.3V), the internal 0.5V reference.