AD5678 Analog Devices, AD5678 Datasheet
AD5678
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AD5678 Summary of contents
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... The AD5678 has an on-chip reference with an internal gain of 2. The AD5678-1 has a 1. ppm/°C reference, giving a full- scale output of 2.5 V; the AD5678-2 has a 2 ppm/°C reference, giving a full-scale output The on-board reference is off at power-up, allowing the use of an external reference ...
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... AD5678 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 AC Characteristics........................................................................ 7 Timing Characteristics ................................................................ 8 Absolute Maximum Ratings............................................................ 9 ESD Caution.................................................................................. 9 Pin Configuration and Function Descriptions........................... 10 Typical Performance Characteristics ........................................... 11 Terminology .................................................................................... 18 Theory of Operation ...................................................................... 20 REVISION HISTORY 2/11—Rev Rev. C Changes to Zero-Code Error Parameter and Offset Error Parameter, Table 1 ...
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... SPECIFICATIONS kΩ to GND Table 1. Parameter Min 2 STATIC PERFORMANCE AD5678 (DAC Resolution 12 Relative Accuracy Differential Nonlinearity AD5678 (DAC Resolution 16 Relative Accuracy Differential Nonlinearity Zero-Code Error Zero-Code Error Drift Full-Scale Error Gain Error Gain Temperature ...
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... Temperature range is −40°C to +105°C, typical at 25°C. 2 Linearity calculated using a reduced code range of AD5678 12-bit DACs (Code 32 to Code 4,064) and AD5678 16-bit DACs (Code 512 to Code 65,024). Output unloaded. 3 Guaranteed by design and characterization; not production tested. 4 Interface inactive ...
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... kΩ to GND Table 2. Parameter Min STATIC PERFORMANCE 2 AD5678 (DAC Resolution 12 Relative Accuracy Differential Nonlinearity AD5678 (DAC Resolution 16 Relative Accuracy Differential Nonlinearity Zero-Code Error Zero-Code Error Drift Full-Scale Error Gain Error Gain Temperature Coefficient ...
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... Temperature range is −40°C to +105°C, typical at 25°C. 2 Linearity calculated using a reduced code range of AD5678 12-bit DACs (Code 32 to Code 4,064) and AD5678 16-bit DACs (Code 512 to Code 65,024). Output unloaded. 3 Guaranteed by design and characterization; not production tested. 4 Interface inactive ...
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... V ± 0.1 V p-p, frequency = MHz REF 0.5 nV-s 2.5 nV-s 3 nV-s 340 kHz ± 0.2 V p-p REF − ± 0.1 V p-p, frequency = 10 kHz REF 120 nV/√Hz DAC code = 0x8400, 1 kHz 100 nV/√Hz DAC code = 0x8400, 10 kHz 15 μV p-p 0 Rev Page AD5678 unless otherwise noted. MIN MAX 3 ...
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... AD5678 TIMING CHARACTERISTICS All input signals are specified with ns/V (10 5.5 V. All specifications T DD Table 4. Limit MIN MAX Parameter ...
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... DD + 0.3 V other conditions above those indicated in the operational DD section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. − T )/θ J MAX A JA Rev Page AD5678 ...
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... Analog Output Voltage from DAC C. The output amplifier has rail-to-rail operation. Analog Output Voltage from DAC D. The output amplifier has rail-to-rail operation. The AD5678 has a common pin for reference input and reference output. When using the internal reference, this is the reference output pin. When using an external reference, this is the reference input pin ...
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... Figure 10. DNL—16-Bit DAC, 1.25 V Internal Reference Rev Page 2.5V REFOUT T = 25°C A CODE Figure 8. DNL 16-Bit DAC, 2.5 V Internal Reference 1.25V REFOUT T = 25°C A CODE 1.25V REFOUT T = 25°C A CODE AD5678 ...
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... AD5678 1 REF T = 25°C 0.8 A 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 500 1000 1500 2000 2500 CODE Figure 11. INL—12-Bit DAC 0. REF T = 25°C A 0.15 0.10 0.05 0 –0.05 –0.10 –0.15 –0.20 0 500 1000 1500 2000 2500 CODE Figure 12. DNL—12-Bit DAC 1 ...
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... 1.20 1.22 1.24 1.26 1.28 1.30 1.32 1.34 1.36 1.38 1.40 1.42 1.44 80 100 Figure 21 REFOUT 5.2 2.02 2.04 2.06 2.08 2.10 2.12 2.14 2.16 2.18 2.20 2.22 2.24 2.26 2.28 Figure 22. I Rev Page AD5678 ZERO-SCALE ERROR OFFSET ERROR 3.2 3.7 4.2 4.7 5 (mA) DD Histogram with External Reference 1.25V V = 2.5V REFOUT I (mA) DD Histogram with Internal Reference ...
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... Figure 24. AD5678-2 Source and Sink Capability 4. 1.25V REFOUT T = 25°C A 3.00 3/4 SCALE 2.00 MIDSCALE 1.00 1/4 SCALE 0 –1.00 –30 –20 –10 0 CURRENT (mA) Figure 25. AD5678-1 Source and Sink Capability FULL SCALE ZERO SCALE FULL SCALE ZERO SCALE Rev Page 2 25° ...
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... MAX(C2)* 2.489 420.0mV 2.488 2.487 2.486 2.485 0 8.0ns/pt Figure 34. Digital-to-Analog Glitch Impulse (Negative) Rev Page AD5678 REF T = 25° OUT CH2 1.0V M100μs 125MS/s 8.0ns/pt A CH1 1.28V Fig ure 32 ...
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... AD5678 2.5000 2.4995 2.4990 2.4985 2.4980 2.4975 2.4970 2.4965 2.4960 2.4955 2.4950 0 64 128 192 256 SAMPLE Figure 35. Analog Crosstalk 2.4900 2.4895 2.4890 2.4885 2.4880 2.4875 2.4870 2.4865 2.4860 2.4855 0 64 128 192 256 SAMPLE Figure 36. DAC-to-DAC Crosstalk ...
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... Figure 42. Settling Time vs. Capacitive Load 10k CH3 5. –5 –10 –15 –20 5V –25 –30 –35 – 10k Rev Page AD5678 CLR V F OUT V B OUT CH2 1.0V M200ns A CH3 1.10V CH4 1.0V Figure 43. Hardware CLR 25°C A 100k 1M FREQUENCY (Hz) Figure 44. Multiplying Bandwidth ...
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... DAC register. Ideally, the output should The zero-code error is always positive in the AD5678, because the output of the DAC cannot go below due to a combination of the offset errors in the DAC and output amplifier. Zero-code error is expressed in millivolts. ...
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... Total harmonic distortion is the difference between an ideal sine wave and its attenuated version using the DAC. The sine wave is used as the reference for the DAC, and the THD is a measure of the harmonics present on the DAC output measured in decibels. Rev Page AD5678 ...
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... The AD5678 has an on-chip reference with an internal gain of 2. The AD5678-1 has a 1. ppm/°C reference, giving a full- scale output of 2.5 V. The AD5678-2 has a 2 ppm/°C reference, giving a full-scale output The on-board reference is off at power-up, allowing the use of an external reference ...
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... Figure 24 and Figure 25. The slew rate is 1.5 V/μs with a ¼ to ¾ scale settling time of 10 μs. SERIAL INTERFACE The AD5678 has a 3-wire serial interface ( SYNC , SCLK, and DIN) that is compatible with SPI, QSPI, and MICROWIRE interface standards as well as most DSPs. See timing diagram of a typical write sequence ...
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... Neither an update of the DAC register contents nor a change in the operating mode occurs—see Figure 49 D15 D14 D13 D12 D11 D10 D9 DATA BITS Figure 47. AD5678 Input Register Content for DAC D11 D10 ...
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... LDAC low the value in the DAC register before powering down ( LDAC high). CLEAR CODE REGISTER The AD5678 has a hardware CLR pin that is an asynchronous clear input. The CLR input is falling edge sensitive . Bringing the CLR line low clears the contents of the input register and the DAC registers to the data contained in the user-configurable CLR register and sets the analog outputs accordingly ...
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... AD5678 Table 9. Internal Reference Register Internal REF Register (DB0 Table 10. 32-Bit Input Shift Register Contents for Reference Set-Up Function MSB DB31 to DB28 DB27 DB26 Don’t cares Command bits (C3 to C0) Table 11. Power-Down Modes of Operation DB9 DB8 Operating Mode 0 0 Normal operation ...
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... Figure 2 . This ground point should be as close as possible to the AD5678. The power supply to the AD5678 should be bypassed with 10 μF and 0.1 μF capacitors. The capacitors should physically be as close as possible to the device, with the 0.1 μF capacitor ideally right up against the device. The 10 μF capacitors are the tantalum bead type important that the 0.1 μ ...
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... ORDERING GUIDE 1 Model Temperature Range AD5678BRUZ-1 −40°C to +105°C AD5678BRUZ-1REEL7 −40°C to +105°C AD5678BRUZ-2 −40°C to +105°C AD5678BRUZ-2REEL7 −40°C to +105°C AD5678ARUZ-2 −40°C to +105°C AD5678ARUZ-2REEL7 −40°C to +105° RoHS Compliant Part. 5.10 5.00 4. 6.40 BSC ...
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... NOTES Rev Page AD5678 ...
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... AD5678 NOTES ©2005–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05299–0–2/11(C) Rev Page ...