ADC121S655 Datasheet, PDF (1/31 Pages) National Semiconductor (TI) – 12-Bit, 200 kSPS to 500 kSPS, Differential Input, Micro Power A/D Converter

ADC121S655
www.ti.com
SNAS402A – MAY 2007 – REVISED MARCH 2013
ADC121S655 12-Bit, 200 kSPS to 500 kSPS, Differential Input, Micro Power A/D Converter
Check for Samples: ADC121S655
FEATURES
1
•23 True Differential Inputs
• Specified Performance from 200 kSPS to 500
kSPS
• External Reference
• Wide Input Common-Mode Voltage Range
• SPI™/ QSPI™/MICROWIRE/DSP Compatible
Serial Interface
APPLICATIONS
• Automotive Navigation
• Portable Systems
• Medical Instruments
• Instrumentation and Control Systems
• Motor Control
• Direct Sensor Interface
KEY SPECIFICATIONS
• Conversion Rate: 200 kSPS to 500 kSPS
• INL: ± 0.95 LSB (max)
• DNL: ± 0.85 LSB (max)
• Offset Error: ± 3.0 LSB (max)
• Gain Error: ± 5.5 LSB (max)
• SINAD: 70 dB (min)
• Power Consumption at V_A = 5 V
– Active, 500 kSPS: 9 mW (typ)
– Active, 200 kSPS: 7 mW (typ)
– Power-Down: 1.5 µW (typ)
DESCRIPTION
The ADC121S655 is a 12-bit, 200 kSPS to 500 kSPS
sampling Analog-to-Digital (A/D) converter that
features a fully differential, high impedance analog
input and an external reference. The reference
voltage can be varied from 1.0V to V_A, with a
corresponding resolution between 244µV and V_A
divided by 4096.
The output serial data is binary 2's complement and
is compatible with several standards, such as SPI,
QSPI, MICROWIRE, and many common DSP serial
interfaces. The differential input, low power
consumption, and small size make the ADC121S655
ideal for direct connection to transducers in battery
operated systems or remote data acquisition
applications.
Operating from a single 5V supply, the supply current
when operating at 500 kSPS is typically 1.8 mA. The
supply current drops down to 0.3 µA typically when
the ADC121S655 enters power-down mode. The
ADC121S655 is available in the VSSOP-8 package.
Operation is specified over the industrial temperature
range of −40°C to +105°C and clock rates of 3.2 MHz
to 8 MHz.
Table 1. Pin-Compatible Alternatives by Speed⁽¹⁾
Resolution
12-bit
Specified for Sample Rate Range of:
50 to 200
ksps
200 to 500
ksps
500 ksps to
1 Msps
ADC121S625 ADC121S655 ADC121S705
(1) All devices are pin compatible.
Connection Diagram
V_REF
+IN
- IN
GND
1
8
2
7
ADC121S655
3
6
4
5
V_A
SCLK
D_OUT
CS
1
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SPI, QSPI are trademarks of Motorola, Incorporated.
2
All other trademarks are the property of their respective owners.
3
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007–2013, Texas Instruments Incorporated