AD7741 Analog Devices, AD7741 Datasheet
AD7741
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AD7741 Summary of contents
Page 1
... The AD7741 has a single-ended voltage input range from REFIN. The AD7742 has a differential voltage input range from –V REF supply consuming typically 6 mA, and also contain a power- down feature that reduces the current consumption to less than 35 A. ...
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... AD7741–SPECIFICATIONS 2 Parameter DC PERFORMANCE Integral Nonlinearity 200 kHz CLKIN MHz CLKIN f = 6.144 MHz CLKIN Offset Error Gain Error 3 Offset Error Drift 3 Gain Error Drift 3 Power Supply Rejection Ratio 5 ANALOG INPUT Input Current Input Voltage Range +2.5 V REFERENCE (REFIN/OUT) REFIN Nominal Input Voltage ...
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... V or more negative than +0 –3– AD7741/AD7742 = +2 6.144 MHz; all specifications T CLKIN Max Units Conditions/Comments 5 0.015 % of Span 0.015 % of Span 0.015 % of Span 40 mV Unipolar Mode 40 mV Bipolar Mode +2 Span Unipolar Mode +2 ...
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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 AD7741/AD7742 features proprietary ESD protection circuitry, permanent dam- age 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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... Active Low Power-Down pin. When this input is low, the part enters power-down mode where it typically consumes current Frequency Output. This pin provides the output of the synchronous VFC. OUT REV. 0 AD7741 PIN FUNCTION DESCRIPTION PIN CONFIGURATION OUT AD7741 ...
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... AD7741/AD7742 Pin No. Mnemonic Function 1 f Frequency Output. This pin provides the output of the synchronous VFC. OUT 2 V Power Supply Input. These parts can be operated from +4. +5.25 V and the supply should be DD adequately decoupled to GND. 3 GND Ground reference point for all circuitry on the part. ...
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... It is expressed in dBs. REV. 0 GENERAL DESCRIPTION The AD7741/AD7742 are a new generation of CMOS synchro- nous Voltage-to-Frequency Converters (VFCs) that use a charge-balance conversion technique. The AD7741 is a single- channel version and the AD7742 is a multichannel version. The ...
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... can be seen from Table II, the AD7741 has one input range configuration whereas the AD7742 has unipolar/bipolar as well as gain options depending on the status of the GAIN and UNI/BIP pins. The transfer function for the AD7741 is shown in Figure 3. Figure 4 shows the AD7742 transfer function for unipolar input range configuration while the AD7742 transfer function for bipolar input range configuration is shown in Figure 5 ...
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... REFIN/OUT unconnected. For the AD7742, REFIN is tied to REFOUT. Alternatively, an external reference, e.g., /7 CLKIN REF192 or AD780, may be used. For the AD7741, this is con- nected to REFIN/OUT and will overdrive the internal refer- ence. For the AD7742 connected directly to the REFIN pin. While the internal reference will be adequate for most applica- tions, power supply rejection and overall regulation may be improved through the use of an external precision reference ...
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... A counter counts the rising edges of f signal is high. Since the gate interval is not synchronized with f , there is a possibility of a counting inaccuracy. Depending OUT error of one count may occur. OUT Figure 10. A/D Conversion Using the AD7741 VFC f CLKIN PD REFOUT f OUT REFIN f OUT ...
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... The input LED of the isolator is driven from the output of the AD7741/AD7742. At the receiver side, the output transistor is operated in the photo-transistor mode. The pulse train can be reconverted to an analog voltage using a frequency-to-voltage converter ...
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... AD7741/AD7742 8-Lead Plastic DIP (N-8) 0.430 (10.92) 0.348 (8.84 0.280 (7.11) 0.240 (6.10 0.325 (8.25) PIN 1 0.100 (2.54) 0.300 (7.62) BSC 0.060 (1.52) 0.210 0.015 (0.38) (5.33) MAX 0.130 0.160 (4.06) (3.30) MIN 0.115 (2.93) 0.022 (0.558) 0.070 (1.77) SEATING PLANE 0.014 (0.356) 0.045 (1.15) 16-Lead Plastic DIP (N-16) 0.840 (21.34) 0.745 (18.92 0.280 (7.11) 0.240 (6.10 PIN 1 ...