AD5781ARUZ-REEL7 Analog Devices Inc, AD5781ARUZ-REEL7 Datasheet
AD5781ARUZ-REEL7
Specifications of AD5781ARUZ-REEL7
Related parts for AD5781ARUZ-REEL7
AD5781ARUZ-REEL7 Summary of contents
Page 1
FEATURES Single 18-bit DAC, ±0.5 LSB INL 7.5 nV/√Hz noise spectral density 0.05 LSB long term linearity stability <0.05 ppm/°C temperature drift 1 μs settling time 1 nV-sec glitch impulse Operating temperature range: −40°C to +125°C 20-lead TSSOP package Wide ...
Page 2
AD5781 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Timing Characteristics ................................................................ 5 Absolute Maximum Ratings ............................................................ 8 ESD ...
Page 3
SPECIFICATIONS V = +12 +16 −16 −12 unloaded unloaded MIN Table 3. Parameter 2 STATIC PERFORMANCE Resolution Integral Nonlinearity Error ...
Page 4
AD5781 Parameter Digital Feedthrough DC Output Impedance (Normal Mode) DC Output Impedance (Output Clamped to Ground) Spurious Free Dynamic Range Total Harmonic Distortion 5 REFERENCE INPUTS V Input Range REFP V Input Range REFN DC Input Impedance Input Capacitance 5 ...
Page 5
TIMING CHARACTERISTICS 5.5 V; all specifications T CC Table 4. Limit Parameter IOV = 1. 3 ...
Page 6
AD5781 SCLK SYNC t 8 SDIN DB23 t 10 LDAC V OUT V OUT CLR V OUT RESET V OUT t 18 SCLK SYNC t 8 SDIN DB23 INPUT ...
Page 7
SCLK SYNC SDIN DB23 INPUT WORD FOR DAC N DB23 SDO UNDEFINED DB0 DB23 INPUT WORD FOR DAC N ...
Page 8
AD5781 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 −34 ...
Page 9
PIN CONFIGURATION AND FUNCTION DESCRIPTION Table 6. Pin Function Descriptions Pin No. Mnemonic Description 1 INV Connection to Inverting Input of External Amplifier. See the AD5781 Features section for further details Analog Output Voltage. OUT 3 V Positive ...
Page 10
AD5781 TYPICAL PERFORMANCE CHARACTERISTICS 0.5 0.4 0.3 0.2 0.1 0 –0.1 AD8676 REFERENCE BUFFERS –0.2 AD8675 OUTPUT BUFFER V = +10V –0.3 REFP V = –10V REFN V = +15V –0 –15V SS –0.5 0 50000 100000 ...
Page 11
AD8676 REFERENCE BUFFERS T T AD8675 OUTPUT BUFFER 0 +5V REFP 0.3 REFN 0.2 0.1 0 –0.1 –0.2 –0 +15V –0 –15V SS –0.5 0 50000 100000 150000 ...
Page 12
AD5781 0.08 0.06 DNL MAX 0.04 0. 25° +10V REFP –10V REFN AD8676 REFERENCE BUFFERS AD8675 OUTPUT BUFFER –0.02 –0.04 –0.06 DNL MIN –0.08 12.5 13.0 13.5 14.0 14.5 V /|V | ...
Page 13
T = 25° +10V REFP V = –10V –0.040 REFN AD8676 REFERENCE BUFFERS AD8675 OUTPUT BUFFER –0.045 12.5 13.0 13.5 14.0 14.5 15.0 V /| Figure 24. Full-Scale ...
Page 14
AD5781 0.16 0.14 0.12 0. 25° +15V –15V SS AD8676 REFERENCE BUFFERS 0.06 AD8675 OUTPUT BUFFER 0.04 0.02 0 5.0 5.5 6.0 6.5 7.0 7.5 8.0 V /|V | (V) REFP ...
Page 15
AD8676 REFERENCE BUFFERS AD8675 OUTPUT BUFFER –0 +15V –15V SS –0 +10V REFP V = –15V –0.8 REFN –1.0 –55 –35 – ...
Page 16
AD5781 35 T AD797 OUTPUT BUFFER 30 WITH 25pF GAIN MODE 20 0x2013A 15 10 0x2007D 5 0 –0.5 0 0.5 1.0 TIME (µs) Figure 42. 125 Code Step Settling Time 50 V ...
Page 17
TERMINOLOGY Relative Accuracy Relative accuracy, or integral nonlinearity (INL measure of the maximum deviation, in LSB, from a straight line passing through the endpoints of the DAC transfer function. A typical INL error vs. code plot is shown ...
Page 18
AD5781 DC Power Supply Rejection Ratio. DC power supply rejection ratio is a measure of the rejection of the output voltage to dc changes in the power supplies applied to the DAC measured for a given dc change ...
Page 19
THEORY OF OPERATION The AD5781 is a high accuracy, fast settling, single, 18-bit, serial input, voltage output DAC. It operates from a V voltage of 7 16.5 V and a V supply of −16 −2.5 V. ...
Page 20
AD5781 Standalone Operation The serial interface works with both a continuous and noncon- tinuous serial clock. A continuous SCLK source can be used only if SYNC is held low for the correct number of clock cycles. In gated clock mode, ...
Page 21
Asynchronous DAC Update In this mode, LDAC is held high while data is being clocked into the input shift register. The DAC output is asynchronously updated by taking LDAC low after SYNC has been taken high. The update now occurs ...
Page 22
AD5781 Control Register The control register controls the mode of operation of the AD5781. Table 11. Control Register MSB DB23 DB22 DB21 DB20 DB19...DB11 W R/ Register address Reserved Table 12. Control Register Functions Function ...
Page 23
Software Control Register This is a write only register in which writing particular bit has the same effect as pulsing the corresponding pin low. Table 14. Software Control Register MSB DB23 DB22 DB21 R/ W Register ...
Page 24
AD5781 AD5781 FEATURES POWER- The AD5781 contains a power-on reset circuit that, as well as resetting all registers to their default values, controls the output voltage during power-up. Upon power-on, the DAC is placed in tristate (its ...
Page 25
Gain of Two Configuration Figure 50 shows an output amplifier configured for a gain of two. The gain is set by the internal matched 6.8 kΩresistors, which are exactly twice the DAC resistance, having the effect of removing an offset ...
Page 26
AD5781 APPLICATIONS INFORMATION TYPICAL OPERATING CIRCUIT Figure 51 shows a typical operating circuit for the AD5781 using an AD8676 for reference buffers and an output buffer. To meet the specified linearity, force sense buffers must be used on the reference ...
Page 27
... OUTLINE DIMENSIONS PIN 1 0.15 0.05 COPLANARITY ORDERING GUIDE Model 1 Temperature Range AD5781BRUZ −40°C to +125°C AD5781BRUZ-REEL7 −40°C to +125°C AD5781ARUZ −40°C to +125°C AD5781ARUZ-REEL7 −40°C to +125° RoHS Compliant Part. 6.60 6.50 6. 4.50 4.40 4.30 6.40 BSC 1 10 ...
Page 28
AD5781 NOTES ©2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D09092-0-7/10(0) Rev Page ...