AD7817 AD [Analog Devices], AD7817 Datasheet
AD7817
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AD7817 Summary of contents
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... QSPI™ protocols and National Semiconductors MICROWIRE™ protocol. For more information refer to the Serial Interface section of this data sheet. The AD7817 is available in a narrow body 0.15" 16-lead small outline IC (SOIC 16-lead, thin shrink small outline pack- age (TSSOP), while the AD7816/AD7818 come in an 8-lead small outline IC (SOIC) and an 8-lead microsmall outline IC (MSOP) ...
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... AD7816/AD7817/AD7818 AD7817–SPECIFICATIONS Parameter DYNAMIC PERFORMANCE 2 Signal to (Noise + Distortion) Ratio 2 Total Harmonic Distortion 2 Peak Harmonic or Spurious Noise 2 Intermodulation Distortion Second Order Terms Third Order Terms 2 Channel-to-Channel Isolation DC ACCURACY Resolution Minimum Resolution for Which No Missing Codes are Guaranteed 10 2 Relative Accuracy ...
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... V External Reference Connected µA max 6 µA typ 10.75 µA max 2 µA typ 4 µW typ 6.4 See Power vs. Throughput Section for µW typ 48.8 Description of Power Dissipation in µW typ 434 Auto Power-Down Mode µW max Typically 6 µW 13.5 –3– AD7816/AD7817/AD7818 = 2.5 V unless IN = 2.5 V REF DD ...
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... High Impedance Capacitance NOTES *B and S Versions apply to AD7817 only. For operating temperature ranges, see Ordering Guide. 1 AD7816 and AD7817 temperature sensors specified with external 2.5 V reference, AD7818 specified with on-chip reference. All other specifications with external and on-chip reference (2.5 V). For See Terminology ...
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... RD/WR Rising Edge to OTI Rising Edge ns min SCLK Rising Edge to CONVST Falling Edge (Acquisition Time of T/H) ns min I 200 OUTPUT PIN C L 50pF 200 –5– AD7816/AD7817/AD7818 = 2.5 V. All specifications unless IN MIN MAX to cross 0 2.4 V for OUT DD 1.6V 10% and 0.4 V ...
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... If the Reference Input Voltage is likely to exceed V during power-up) and the reference is capable of supplying more recommended to use a clamping diode between the REF diagram below shows how the diode should be connected. –6– by more than 0.3 V (e.g., DD pin and V pin. The REF DD IN BAT81 AD7816/AD7817 REV. C ...
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... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD7816/AD7817/AD7818 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
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... Logic Input. Data is clocked into the AD7817 at this pin SCLK Clock Input for the Serial Port. The serial clock is used to clock data into and out of the AD7817. Data is clocked out on the falling edge and clocked in on the rising edge. 16 RD/WR Logic Input Signal. The read/write signal is used to indicate to the AD7817 whether the data transfer operation is a read or a write ...
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... Intermodulation terms are those for which neither m nor n are equal to zero. For example, the second /2), excluding dc. S order terms include (fa + fb) and (fa – fb), while the third order terms include (2fa + fb), (2fa – fb), (fa + 2fb) and (fa – 2fb). –9– AD7816/AD7817/AD7818 + ...
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... AD7816/AD7817/AD7818 The AD7816, AD7817, and AD7818 are tested using the CCIF standard where two input frequencies near the top end of the input bandwidth are used. In this case, the second and third order terms are of different significance. The second order terms are usually distanced in frequency from the original sine waves while the third order terms are usually at a frequency close to the input frequencies ...
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... ANALOG INPUTS Analog Input Figure 7 shows an equivalent circuit of the analog input struc- ture of the AD7817 and AD7818. The two diodes D1 and D2 provide ESD protection for the analog inputs. Care must be taken to ensure that the analog input signal never exceeds the supply rails by more than 200 mV. This will cause these diodes to become forward biased and start conducting current into the substrate ...
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... V BALANCE 1.2V ADC TRANSFER FUNCTION The output coding of the AD7816, AD7817, and AD7818 is straight binary. The designed code transitions occur at succes- sive integer LSB values (i.e., 1 LSB, 2 LSBs, etc.). The LSB size is = 2.5 V/1024 = 2.44 mV. The ideal transfer characteristic is shown in Figure 10 below. 111...111 111 ...
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... TEMPERATURE MEASUREMENT ERROR DUE TO REFERENCE ERROR The AD7816, AD7817, and AD7818 are trimmed using a pre- cision 2.5 V reference to give the transfer function described previously. To show the effect of the reference tolerance on a temperature reading, the temperature sensor transfer function can be rewritten as a function of the reference voltage and the temperature ...
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... The devices are powered up again on the rising edge of the CONVST signal. Superior power performance can be achieved in this mode of operation by powering up the AD7816, FLUID AD7817, and AD7818 only to carry out a conversion (see Power vs. Throughput section). In Figure 17 the CS line is applicable HEATSINK to the AD7817 only. ...
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... the power up time µs and the conversion time is 9 µs, the AD7817 can be said to dissipate 4.8 mW typically for 11 µs (worst case) during each conversion cycle. If the throughput rate is 10 kSPS, the cycle time is 100 µs and the power dissipated while powered up dur- ing each cycle is (11/100) × ...
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... Simplifying the Serial Interface To minimize the number of interconnect lines to the AD7817, the user can connect the CS line to DGND. This is possible if the AD7817 is not sharing the serial bus with another device also possible to tie the D and D IN OUT arrangement is compatible with the 8051 microcontroller ...
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... COMPLIANT TO JEDEC STANDARDS MO-187AA 16-Lead Thin Shrink Small Outline Package [TSSOP] 16 4.50 4.40 4.30 0.50 (0.0197 0.25 (0.0098) PIN 1.27 (0.0500) 0.15 0.40 (0.0157) 0.05 0.65 BSC COPLANARITY COMPLIANT TO JEDEC STANDARDS MO-153AB –17– AD7816/AD7817/AD7818 14a 13 DB7 DB1 DB0 (RM-8) Dimensions shown in millimeters 3.00 BSC 8 5 4.90 BSC 1 4 0.65 BSC 1 ...
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... AD7816/AD7817/AD7818 Revision History Location 9/04—Data Sheet changed from REV REV. C. Updated ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Changes to Operating Modes section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Changes to Figure Changes to Figure Changes to AD7817 Serial Interface, Read Operation section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Changes to Figure Changes to Figure –18– Page REV. C ...
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