Datasheet AD7170 (Analog Devices)

12-Bit Low Power Sigma-Delta ADC Data Sheet AD7170 FEATURES FUNCTIONAL BLOCK DIAGRAM Output data rate: 125 Hz GND VDD REFIN(+) REFIN(–) Pin-programmable power-down and reset Status function AIN(+) DOUT/RDY Internal clock oscillator 12-BIT Σ-Δ ADC AIN(–) SCLK Current: 135 µA Power supply: 2.7 V to 5.25 V PDRST AD7170 INTERNAL
001
−40°C to +105°C temperature range CLOCK
08416-
Package: 10-lead, 3 mm × 3 mm LFCSP
Figure 1.
INTERFACE Table 1. 2-wire serial (read-only device) P-P SPI compatible VREF = VDD RMS Noise P-P Noise Resolution ENOB Schmitt trigger on SCLK
5 V 11.5 μV 76 μV 12 bits 12 bits
APPLICATIONS
3 V 6.9 μV 45 μV 12 bits 12 bits
Pressure measurement Industrial process control Portable instrumentation GENERAL DESCRIPTION
The AD7170 is a very low power 12-bit analog-to-digital converter The output data rate of the AD7170 is 125 Hz, whereas the (ADC). It contains a precision 12-bit sigma-delta (Σ-Δ) ADC settling time is 24 ms. The AD7170 has one differential input and an on-chip oscillator. Consuming only 135 μA, the AD7170 and a gain of 1. This is useful in applications where the user is particularly suitable for portable or battery operated products needs to use an external amplifier to implement system-specific where very low power is a requirement. The AD7170 also has a filtering or gain requirements. power-down mode in which the device consumes 5 μA, thus The AD7170 operates with a power supply from 2.7 V to 5.25 V. increasing the battery life of the product. It is available in a 10-lead LFCSP package. For ease-of-use, all the features of the AD7170 are control ed by The AD7171 is a 16-bit version of the AD7170. It has the same dedicated pins. Each time a data read occurs, eight status bits feature set as the AD7170 and is pin-for-pin compatible. are appended to the 12-bit conversion. These status bits contain a pattern sequence that can be used to confirm the validity of the serial transfer.
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Document Outline FEATURES INTERFACE APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING CHARACTERISTICS TIMING DIAGRAMS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS OUTPUT NOISE AND RESOLUTION SPECIFICATIONS ADC CIRCUIT INFORMATION OVERVIEW FILTER, DATA RATE, AND SETTLING TIME GAIN POWER-DOWN/RESET (PDRST\) ANALOG INPUT CHANNEL BIPOLAR CONFIGURATION DATA OUTPUT CODING REFERENCE DIGITAL INTERFACE GROUNDING AND LAYOUT APPLICATIONS INFORMATION TEMPERATURE SYSTEM SIGNAL CONDITIONING CIRCUIT OUTLINE DIMENSIONS ORDERING GUIDE