adc122s625eb National Semiconductor Corporation, adc122s625eb Datasheet

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adc122s625eb

Manufacturer Part Number
adc122s625eb
Description
Adc122s625 Dual 12-bit, 50 Ksps To 200 Ksps, Simultaneous Sampling A/d Converter
Manufacturer
National Semiconductor Corporation
Datasheet
© 2008 National Semiconductor Corporation
ADC122S625
Dual 12-Bit, 50 kSPS to 200 kSPS, Simultaneous Sampling
A/D Converter
General Description
The ADC122S625 is a dual 12-bit, 50 kSPS to 200 kSPS si-
multaneous 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 ADC122S625 features an external
reference that can be varied from 1.0V to V
The ADC122S625's serial data output is binary 2's comple-
ment and is compatible with several standards, such as
SPI™, QSPI™, MICROWIRE™, and many common DSP se-
rial interfaces. The serial clock (SCLK) and chip select bar
(CS) are shared by both channels.
Operating from a single 5V analog supply and a reference
voltage of 2.5V, the total power consumption while operating
at 200 kSPS is typically 8.6 mW. With the ADC122S625 op-
erating in power-down mode, the power consumption re-
duces to 2.6 µW. The differential input, low power consump-
tion, and small size make the ADC122S625 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 1.6 MHz to 6.4
MHz. The ADC122S625 is available in a 10-lead MSOP pack-
age.
Connection Diagram
TRI-STATE® is a trademark of National Semiconductor Corporation.
MICROWIRE™ is a trademark of National Semiconductor Corporation.
QSPI™ and SPI™ are trademarks of Motorola, Inc.
300553
A
.
Features
Key Specifications
Applications
True Simultaneous Sampling Differential Inputs
Guaranteed performance from 50 kSPS to 200 kSPS
External Reference
Wide Input Common-Mode Voltage Range
Single High-Speed Serial Data Output
Operating Temperature Range of −40°C to +105°C
SPI™/QSPI™/MICROWIRE™/DSP compatible Serial
Interface
Conversion Rate
INL
DNL
SNR
THD
ENOB
Power Consumption at 200 kSPS
Motor Control
Power Meters/Monitors
Multi-Axis Positioning Systems
Instrumentation and Control Systems
Data Acquisition Systems
Medical Instruments
Direct Sensor Interface
Converting, V
Power-Down, V
30055305
A
= 5V, V
A
= 5V, V
REF
REF
= 2.5V
= 2.5V
50 kSPS to 200 kSPS
February 25, 2008
±0.95 LSB (max)
11.25 bits (min)
www.national.com
±1 LSB (max)
-72 dBc (min)
8.6 mW (typ)
71 dBc (min)
2.6 µW (typ)

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adc122s625eb Summary of contents

Page 1

... MHz to 6.4 MHz. The ADC122S625 is available in a 10-lead MSOP pack- age. Connection Diagram TRI-STATE® trademark of National Semiconductor Corporation. MICROWIRE™ trademark of National Semiconductor Corporation. QSPI™ and SPI™ are trademarks of Motorola, Inc. © 2008 National Semiconductor Corporation Features ■ ...

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... Ordering Information Order Code Temperature Range ADC122S625CIMM −40°C to +105°C ADC122S625CIMMX −40°C to +105°C ADC122S625EB Block Diagram www.national.com Description 10-Lead MSOP Package, 1000 Units Tape & Reel 10-Lead MSOP Package, 3500 Units Tape & Reel Evaluation Board 2 Top Mark ...

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Pin Descriptions and Equivalent Circuits Pin No. Symbol V 1 REF 2 CHA+ 3 CHA− 4 CHB− 5 CHB+ 6 GND OUT 9 SCLK 10 CS Description Voltage Reference Input. A voltage reference between 1V ...

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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Analog Supply Voltage V A Voltage on Any Pin to GND Input Current at Any Pin (Note 3) Package ...

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Symbol Parameter V Reference Voltage Range REF DIGITAL INPUT CHARACTERISTICS V Input High Voltage IH V Input Low Voltage IL I Input Current IN C Input Capacitance IND DIGITAL OUTPUT CHARACTERISTICS V Output High Voltage OH V Output Low Voltage ...

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ADC122S625 Timing Specifications The following specifications apply for V noted. Boldface limits apply for T A Symbol Parameter t CS Setup Time prior to an SCLK rising edge CSSU t D Enable Time after the falling edge ...

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Timing Diagrams FIGURE 1. ADC122S625 Single Conversion Timing Diagram FIGURE 2. ADC122S625 Continuous Conversion Timing Diagram FIGURE 3. D Rise and Fall Times OUT FIGURE 4. D Hold and Access Times OUT 30055306 FIGURE 5. Valid CS Assertion Times 30055311 ...

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Specification Definitions APERTURE DELAY is the time between the fourth falling edge of SCLK and the time when the input signal is acquired or held for conversion. COMMON MODE REJECTION RATIO (CMRR measure of how well in-phase signals ...

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Typical Performance Characteristics 6.4 MHz kHz unless otherwise stated. IN DNL - 200 kSPS DNL vs DNL vs. V REF V = 5.0V 2.5V REF INL - 200 kSPS 30055321 30055323 ...

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Typical Performance Characteristics 6.4 MHz kHz unless otherwise stated. IN DNL vs. SCLK FREQUENCY DNL vs. TEMPERATURE SINAD vs. V www.national.com V = 5.0V REF 30055325 30055329 A 30055333 10 = 2.5V +25°C, ...

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Typical Performance Characteristics 6.4 MHz kHz unless otherwise stated. IN SINAD vs. V REF SINAD vs. SCLK FREQUENCY SINAD vs. INPUT FREQUENCY V = 5.0V 2.5V REF 30055337 THD vs. SCLK FREQUENCY 30055341 ...

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Typical Performance Characteristics 6.4 MHz kHz unless otherwise stated. IN SINAD vs. TEMPERATURE V CURRENT vs CURRENT vs. TEMPERATURE A www.national.com V = 5.0V 2.5V REF 30055372 V A 30055374 ...

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Typical Performance Characteristics 6.4 MHz kHz unless otherwise stated CURRENT vs. TEMP REF SPECTRAL RESPONSE - 200 kSPS V = 5.0V 2.5V REF CMRR vs. CM RIPPLE FREQ 30055351 30055314 13 ...

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Functional Description The ADC122S625 is a dual 12-bit, simultaneous sampling Analog-to-Digital (A/D) converter. The converter is based on a successive-approximation register (SAR) architecture where the differential nature of the analog inputs is main- tained from the internal track-and-hold circuits throughout ...

Page 15

Single-Ended Input Operation For single-ended operation, the non-inverting inputs of the ADC122S625 can be driven with a signal that has a maximum to minimum value range that is equal to or less than twice the reference voltage. The inverting ...

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SCLK. In the third condition, CS and SCLK go low simultaneously and the ADC122S625 immediately enters acquisition mode. While there is no timing restriction with respect to the falling edges of CS and ...

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POWER SUPPLY CONSIDERATIONS AND PCB LAYOUT For best performance, care should be taken with the physical layout of the printed circuit board. This is especially true with a low reference voltage or when the conversion rate is high. At ...

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FIGURE 12. Interfacing the ADC122S625 to a Current Transducer 6.3 Bridge Sensor Application Figure 13 shows an example of interfacing the ADC122S625 ...

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Physical Dimensions inches (millimeters) unless otherwise noted 10-Lead MSOP Order Number ADC122S625CIMM NS Package Number MUB10A 19 www.national.com ...

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... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...

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