AD5791 Analog Devices, AD5791 Datasheet
AD5791
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AD5791 Summary of contents
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... GENERAL DESCRIPTION 1 The AD5791 is a single 20-bit, unbuffered voltage-output DAC that operates from a bipolar supply The AD5791 accepts a positive reference input in the range and a negative reference input in the range V The AD5791 offers a relative accuracy specification of ±1 LSB max, and operation is guaranteed monotonic with a ± ...
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... DAC Architecture....................................................................... 20 Serial Interface ............................................................................ 20 Hardware Control Pins.............................................................. 21 On-Chip Registers...................................................................... 22 AD5791 Features ............................................................................ 25 Power- V......................................................................... 25 Configuring the AD5791 .......................................................... 25 DAC Output State ...................................................................... 25 Linearity Compensation............................................................ 25 Output Amplifier Configuration.............................................. 25 Applications Information .............................................................. 27 Typical Operating Circuit ......................................................... 27 ...
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... REFN REFP 50 V/μs 1 μs 1 μs 7.5 nV/√Hz 7.5 nV/√Hz 7.5 nV/√Hz 1.1 μV p-p Rev Page AD5791 = 1. 5 Test Conditions/Comments B version + −10 V, REFP REFN T = 0°C to 105° version + −10 V REFP REFN 3 B version ...
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... X2 gain mode compensation capacitor on AD797. 7 Includes noise contribution from AD8676BRZ voltage reference buffers. 8 The AD5791 is configured in bias compensation mode with a low-pass RC filter on the output 300 Ω 143 pF.(total capacitance seen by the output buffer, lead capacitance, and so forth). 9 Current flowing in an individual logic pin. 10 Includes PSRR of AD8676BRZ voltage reference buffers ...
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... SCLK rising edge to SDO valid ( min SYNC rising edge to SCLK rising edge ignore 35 ns typ RESET pulse width low 150 ns typ RESET pulse activation time ) and timed from a voltage level Rev Page AD5791 = ...
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... AD5791 SCLK SYNC t 8 SDIN DB23 t 10 LDAC V OUT V OUT CLR V OUT RESET V OUT t 17 SCLK SYNC t 8 SDIN DB23 INPUT WORD SPECIFIES REGISTER TO BE READ SDO DB0 t 15 ...
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... DB23 INPUT WORD FOR DAC N DB23 SDO DB0 DB23 INPUT WORD FOR DAC N – 1 DB0 DB23 INPUT WORD FOR DAC N UNDEFINED Figure 4. Daisy-Chain Mode Timing Diagram Rev Page AD5791 DB0 DB0 ...
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... AD5791 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. Transient currents 100 mA do not cause SCR latch-up. Table 5. Parameter Rating V to AGND −0 + AGND − +0 −0 + DGND −0 ...
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... PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions Pin No. Mnemonic Description 1 INV Connection to Inverting Input of External Amplifier. See the AD5791 Features section for further details Analog Output Voltage. OUT 3 V Positive Reference Sense Voltage Input. A voltage range ...
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... AD5791 TYPICAL PERFORMANCE CHARACTERISTICS 1.0 AD8676 REFERENCE BUFFERS 0.8 AD8675 OUTPUT BUFFER 0.6 0.4 0.2 0 –0.2 –0 +10V –0.6 REFP V = –10V REFN V = +15V –0 –15V SS –1.0 0 200000 400000 600000 DAC CODE Figure 6. Integral Nonlinearity Error vs. DAC Code, ±10 V Span 1 +125°C AD8676 REFERENCE BUFFERS +25°C ...
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... AD8675 OUTPUT BUFFER 0 INL MIN –0.1 –0.2 –0.3 12.5 13.0 13.5 14.0 14.5 15.0 15.5 V /| 1.5 INL MAX 1 25° +5V REFP REFN AD8676 REFERENCE BUFFERS 0 AD8675 OUTPUT BUFFER INL MIN 7.5 8.5 9.5 10.5 11.5 12.5 13.5 14.5 V (V) DD –2.5 –3.9 –5.3 –6.7 –9.1 –10.5 –12.9 –14.2 –15.5 –16.5 V (V) SS AD5791 85 105 125 16.0 16.5 15.5 16.5 ...
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... AD5791 0.4 DNL MAX 0.3 0.2 0 25° +10V REFP –10V REFN AD8676 REFERENCE BUFFERS AD8675 OUTPUT BUFFER –0.1 –0.2 –0.3 DNL MIN –0.4 12.5 13.0 13.5 14.0 14.5 15.0 V /| Figure 18. Differential Nonlinearity Error vs. Supply Voltage, ±10 V Span 0.4 DNL MAX 0 25° +5V –0.2 REFP ...
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... REFP REFN Figure 28. Integral Nonlinearity Error vs. Reference Voltage 0.4 DNL MAX 0.3 0.2 0 25° +15V –15V –0.1 SS AD8676 REFERENCE BUFFERS –0.2 AD8675 OUTPUT BUFFER –0.3 –0.4 –0.5 DNL MIN –0.6 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 V /|V | (V) REFP REFN Figure 29. Differential Nonlinearity Error vs. Reference Voltage AD5791 14.5 15.5 16.5 9.0 9.5 10.0 9.0 9.5 10.0 ...
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... AD5791 0.60 0.55 0.50 0. 25° +15V DD 0. –15V SS AD8676 REFERENCE BUFFERS AD8675 OUTPUT BUFFER 0.35 0.30 5.0 5.5 6.0 6.5 7.0 7.5 8.0 V /|V | (V) REFP REFN Figure 30. Zero-Scale Error vs. Reference Voltage 0.15 0.10 0. 25°C –0. +15V –15V SS –0.10 AD8676 REFERENCE BUFFERS AD8675 OUTPUT BUFFER –0.15 –0.20 5.0 5.5 6.0 6.5 7.0 7.5 8.0 V /|V | (V) REFP REFN Figure 31. Midscale Error vs. Reference Voltage ...
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... LOAD = 10MΩ||20pF 4 CH3 5V CH4 5V 200ns Figure 40. Rising Full-Scale Voltage Step V = +15V –15V +10V REFP V = –10V REFN AD8676 REFERENCE BUFFERS OUTPUT UNBUFFERED LOAD = 10MΩ||20pF 3 4 CH3 5V CH4 5V 200ns Figure 41. Falling Full-Scale Voltage Step AD5791 ...
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... AD5791 10.8 ±10V V REF OUTPUT GAIN OF 1 10.6 BIAS COMPENSATION MODE 20pF COMPENSATION CAPACITOR RC LOW-PASS FILTER 10.4 10.2 10.0 9.8 9.6 9 TIME (µs) Figure 42. 500 Code Step Settling Time REF 9 OUTPUT GAIN OF 1 BIAS COMPENSATION MODE 20pF COMPENSATION CAPACITOR 8 RC LOW-PASS FILTER POSITIVE CODE ...
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... REFP 250 V REFN AD8675 OUTPUT BUFFER 200 150 100 50 0 –50 – TIME (µs) Figure 49. Glitch Impulse on Removal of Output Clamp V = +15V –15V +10V REFP V = –10V REFN CODE = MIDSCALE 1k 10k 100k = +10V = –10V Rev Page AD5791 ...
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... For fast settling applications, a high speed buffer amplifier is required to buffer the load from the 3.4 kΩ output impedance of the AD5791, in which case it is the amplifier that determines the settling time. Digital-to-Analog Glitch Impulse ...
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... AC Power Supply Rejection Ratio (AC PSRR) AC power supply rejection ratio is a measure of the rejection of the output voltage to ac changes in the power supplies applied to the DAC measured for a given amplitude and frequency change in power supply voltage and is expressed in decibels. Rev Page AD5791 ...
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... AGND through a ~6 kΩ internal resistor. OUT DAC ARCHITECTURE The architecture of the AD5791 consists of two matched DAC sections. A simplified circuit diagram is shown in Figure 50. The six MSBs of the 20-bit data-word are decoded to drive 63 switches E62. Each of these switches connects one of 63 ...
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... DAC updating or asynchronous DAC updating Synchronous DAC Update In this mode, LDAC is held low while data is being clocked into the input shift register. The DAC output is updated on the rising edge of SYNC . Rev Page AD5791 AD5781* SDIN SCLK SYNC SDO SDIN ...
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... The AD5791 The AD5791 The DAC register is loaded with the clearcode register value and the output is set accordingly The output is set according to the DAC register value The DAC register is loaded with the clearcode register value and the output is set accordingly. ...
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... Data Sheet Control Register The control register controls the mode of operation of the AD5791. Table 11. Control Register MSB DB23 DB22 DB21 DB20 DB19…DB11 W Register address Reserved R/ Table 12. Control Register Functions Function Description Reserved These bits are reserved and should be programmed to zero. ...
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... DAC register coding that is being used, either binary or twos complement. RESET Setting this bit returns the DB20 DB19 DB3 Software control register data 0 Reserved AD5791 to its power-on state. Rev Page Data Sheet DB2 DB1 DB0 1 2 RESET ...
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... V and shown in Table 12. OUTPUT AMPLIFIER CONFIGURATION There are a number of different ways that an output amplifier can be connected to the AD5791, depending on the voltage references applied and the desired output voltage span. Unity Gain Configuration Figure 52 shows an output amplifier configured for unity gain, ...
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... Logic 0. V REFP 1/2 AD8676 V V REFPF REFPS A1 20-BIT DAC V V REFNF REFNS 1/2 AD8676 REFN Figure 54. Output Amplifier in Gain of Two Configuration Rev Page Data Sheet 6.8kΩ 6.8kΩ 10pF INV V OUT V OUT AD8675, ADA4898-1 AD5791 ...
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... To meet the specified linearity, force sense buffers Figure 55. Typical Operating Circuit must be used on the reference inputs. Because the output AD5791 impedance of the required for driving low resistive, high capacitance loads. Rev Page AD5791 AD5791 is 3.4 kΩ, an output buffer is ...
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... OUTLINE DIMENSIONS COPLANARITY ORDERING GUIDE 1 Model Temperature Range AD5791BRUZ −40°C to +125°C AD5791ARUZ −40°C to +125°C EVAL-AD5791SDZ RoHS Compliant Part. ©2010–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D08964-0-11/11(C) 6.60 6.50 6. ...