AD AD4003BRMZ Precision, differential sar adc Datasheet

18-Bit, 2 MSPS/1 MSPS/500 kSPS,
Precision, Differential SAR ADCs
AD4003/AD4007/AD4011
Data Sheet
FEATURES
GENERAL DESCRIPTION
Throughput: 2 MSPS/1 MSPS/500 kSPS options
INL: ±1.0 LSB (±3.8 ppm) maximum
Guaranteed 18-bit no missing codes
Low power
9.5 mW at 2 MSPS, 4.9 mW at 1 MSPS, 2.4 mW at 500 kSPS
(VDD only)
80 μW at 10 kSPS, 16 mW at 2 MSPS (total)
SNR: 100.5 dB typical at 1 kHz, VREF = 5 V; 99 dB typical at
100 kHz
THD: −123 dB typical at 1 kHz, VREF = 5 V; −100 dB typical at
100 kHz
Ease of use features reduce system power and complexity
Input overvoltage clamp circuit
Reduced nonlinear input charge kickback
High-Z mode
Long acquisition phase
Input span compression
Fast conversion time allows low SPI clock rates
SPI-programmable modes, read/write capability, status word
Differential analog input range: ±VREF
0 V to VREF with VREF from 2.4 V to 5.1 V
Single 1.8 V supply operation with 1.71 V to 5.5 V logic interface
SAR architecture: no latency/pipeline delay, valid first
conversion
First conversion accurate
Guaranteed operation: −40°C to +125°C
SPI-/QSPI-/MICROWIRE-/DSP-compatible serial interface
Ability to daisy-chain multiple ADCs and busy indicator
10-lead packages: 3 mm × 3 mm LFCSP, 3 mm × 4.90 mm MSOP
The AD4003/AD4007/AD4011 are low noise, low power, high
speed, 18-bit, precision successive approximation register (SAR)
analog-to-digital converters (ADCs). The AD4003, AD4007, and
AD4011 offer 2 MSPS, 1 MSPS, and 500 kSPS throughputs,
respectively. They incorporate ease of use features that reduce
signal chain power consumption, reduce signal chain complexity,
and enable higher channel density. The high-Z mode, coupled with
a long acquisition phase, eliminates the need for a dedicated high
power, high speed ADC driver, thus broadening the range of low
power precision amplifiers that can drive these ADCs directly while
still achieving optimum performance. The input span compression
feature enables the ADC driver amplifier and the ADC to operate
off common supply rails without the need for a negative supply
while preserving the full ADC code range. The low serial
peripheral interface (SPI) clock rate requirement reduces the digital
input/output power consumption, broadens processor options, and
simplifies the task of sending data across digital isolation.
Operating from a 1.8 V supply, the AD4003/AD4007/AD4011 have
a ±VREF fully differential input range with VREF ranging from 2.4 V
to 5.1 V. The AD4003 consumes only 16 mW at 2 MSPS with a
minimum SCK rate of 75 MHz in turbo mode, the AD4007
consumes only 8 mW at 1 MSPS, and the AD4011 consumes only 4
mW at 500 kSPS. The AD4003/AD4007/AD4011 all achieve ±1.0
LSB integral nonlinearty error (INL) maximum, guaranteed no
missing codes at 18 bits with 100.5 dB typical signal-to-noise ratio
(SNR) for 1 kHz inputs. The reference voltage is applied externally
and can be set independently of the supply voltage.
The SPI-compatible versatile serial interface features seven different
modes including the ability, using the SDI input, to daisy-chain
several ADCs on a single 3-wire bus and provides an optional busy
indicator. The AD4003/AD4007/AD4011 are compatible with 1.8
V, 2.5 V, 3 V, and 5 V logic, using the separate VIO supply.
The AD4003/AD4007 are available in a 10-lead MSOP and LFCSP,
and the AD4011 is available in a 10-lead LFCSP, with operation
specified from −40°C to +125°C. The devices are pin compatible
with the 16-bit, 2 MSPS AD4000 (see Table 8).
APPLICATIONS
Automatic test equipment
Machine automation
Medical equipment
Battery-powered equipment
Precision data acquisition systems
FUNCTIONAL BLOCK DIAGRAM
2.5V TO 5V
10µF
1.8V
VREF
VREF /2
0
IN+
IN–
AD4003/
AD4007/
AD4011
HIGH-Z
MODE
TURBO
MODE
18-BIT
SAR ADC
CLAMP
VDD
SERIAL
INTERFACE
STATUS
BITS
SPAN
COMPRESSION
GND
VIO 1.8V TO 5V
SDI
SCK
SDO
CNV
3-WIRE OR 4-WIRE
SPI INTERFACE
(DAISY CHAIN, CS)
14957-001
REF
VREF
VREF/2
0
Figure 1.
Rev. B
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AD4003/AD4007/AD4011
Data Sheet
TABLE OF CONTENTS
Features ............................................................................................... 1
Driver Amplifier Choice ........................................................... 22
Applications ........................................................................................ 1
Ease of Drive Features ............................................................... 23
General Description ........................................................................... 1
Voltage Reference Input ............................................................ 24
Functional Block Diagram .............................................................. 1
Power Supply............................................................................... 25
Revision History ............................................................................... 3
Digital Interface .......................................................................... 25
Specifications..................................................................................... 4
Register Read/Write Functionality........................................... 26
Timing Specifications .................................................................. 7
Status Word ................................................................................. 28
Absolute Maximum Ratings............................................................ 9
CS Mode, 3-Wire Turbo Mode ................................................. 29
Thermal Resistance ...................................................................... 9
CS Mode, 3-Wire Without Busy Indicator ............................. 30
ESD Caution .................................................................................. 9
CS Mode, 3-Wire with Busy Indicator .................................... 31
Pin Configurations and Function Descriptions ......................... 10
CS Mode, 4-Wire Turbo Mode ................................................. 32
Typical Performance Characteristics ........................................... 11
CS Mode, 4-Wire Without Busy Indicator ............................. 33
Terminology .................................................................................... 16
Theory of Operation ...................................................................... 17
Circuit Information .................................................................... 17
Converter Operation .................................................................. 18
Transfer Functions...................................................................... 18
Applications Information .............................................................. 19
CS Mode, 4-Wire with Busy Indicator .................................... 34
Daisy-Chain Mode ..................................................................... 35
Layout Guidelines....................................................................... 36
Evaluating the AD4003/AD4007/AD4011 Performance ...... 36
Outline Dimensions ....................................................................... 37
Ordering Guide .......................................................................... 38
Typical Application Diagrams .................................................. 19
Analog Inputs .............................................................................. 20
Rev. B | Page 2 of 38
Data Sheet
AD4003/AD4007/AD4011
REVISION HISTORY
10/2017—Rev. A to Rev. B
Changes to Features and General Description .............................. 1
Moved Figure 1 .................................................................................. 1
Changes to Specifications Section and Table 1.............................. 4
Changes to Endnote 1 and Endnote 2, Table 1 .............................. 6
Changes to Timing Specifications Section, CNV or SDI Low to
SDO D17 (MSB) Valid Delay (CS Mode) Parameter, Table 2 .... 7
Changes to Endnote 3, Table 2 ........................................................ 7
Changes to Analog Input Parameter, Table 5 ................................ 9
Added Endnote 2, Table 5 ................................................................ 9
Changes to Figure 4 and Table 7 ...................................................10
Changes to Typical Performance Characteristics Section .........11
Reorganized Typical Performance Characteristics Section .......11
Changes to Figure 19 and Figure 19 Caption ..............................13
Changes to Figure 25 Caption through Figure 27 Caption and
Changes to Figure 28 ......................................................................14
Changes to Circuit Information Section and Table 8 .................17
Changes to Converter Operations Section and Table 9 .............18
Changes to Endnote 1 and Endnote 2, Table 9 ............................18
Changes to Applications Information Section ............................19
Moves Figure 38; Renumbered Sequentially ...............................20
Change to Analog Input Section ...................................................20
Changes to Input Overvoltage Clamp Section................................... 21
Changes to High Frequency Input Signals Section, Multiplexed
Applications Section, Driver Amplifier Choice Section, RC Filter
Values Section, Figure 39, and Figure 40 Caption ............................. 22
Changes to High-Z Mode Section, Figure 42, Figure 43, and
Figure 43 Caption ............................................................................23
Changes to Voltage Reference Input Section, Figure 44 Caption,
Figure 45, Figure 46 Caption, and Figure 47 ...............................24
Changes to Digital Interface Section, Power Supply Section, and
Figure 48 Caption ............................................................................25
Changes to Read/Write Functionality Section, Table 12, and
Table 14 .............................................................................................26
Changes to Figure 49 ......................................................................27
Changes to Status Word Section and Table 15 ............................28
Changes to CS Mode, 4-Wire Turbo Mode Section .......................32
Changes to CS Mode, 4-Wire Without Busy Indicator Section .....33
Changes to CS Mode, 4-Wire With Busy Indicator Section......34
Change to Daisy-Chain Mode Section .........................................35
Changes to Evaluating the AD4003/AD4007/AD4011
Performance Section .......................................................................36
Changes to Ordering Guide ...........................................................38
7/2017—Rev. 0 to Rev. A
Added AD4007 and AD4011............................................ Universal
Changes to Features Section and General Description................ 1
Moved Figure 1 .................................................................................. 3
Changes to Specifications Section .................................................. 4
Changes to Table 1 ............................................................................ 4
Changes to Timing Specifications Section .................................... 7
Changes to Table 2 ............................................................................ 7
Changes to Absolute Maximum Ratings Section ......................... 9
Added Endnote 2 and Endnote 3, Table 6 ..................................... 9
Changes to Typical Performance Characteristics Section ......... 11
Changes to Figure 11 and Figure 14 ............................................. 12
Changes to Figure 19 and Figure 21 ............................................. 13
Added Figure 25 and Figure 26; Renumbered Sequentially ...... 14
Moved Terminology Section ......................................................... 16
Changes to Terminology Section .................................................. 16
Changes to Circuit Information Section and Table 8 ................. 17
Moved Figure 38 .............................................................................. 22
Changes to High Frequency Input Signals Section .................... 22
Added Multiplexed Applications Section .................................... 22
Added Figure 41 .............................................................................. 23
Moved Figure 42 .............................................................................. 23
Changes to High-Z Mode Section and Figure 43 ....................... 23
Changes to Voltage Reference Input Section ............................... 24
Changes to Figure 48, Digital Interface Section, and Table 11 ....... 25
Changes to CS Mode, 3-Wire Turbo Mode Section ................... 29
Added Figure 53 .............................................................................. 29
Changes to CS Mode, 4-Wire Turbo Mode Section ................... 32
Added Figure 59 .............................................................................. 32
Change to CS Mode, 4-Wire with Busy Signal Indicator
Section .............................................................................................. 34
Changes to Layout Guidelines Section and Evaluating the
AD4003/AD4007/AD4011 Performance Section ....................... 36
Updated Outline Dimensions........................................................ 37
Changes to Ordering Guide ........................................................... 38
10/2016—Revision 0: Initial Version
Rev. B | Page 3 of 38
AD4003/AD4007/AD4011
Data Sheet
SPECIFICATIONS
VDD = 1.71 V to 1.89 V; VIO = 1.71 V to 5.5 V; VREF = 5 V; all specifications TMIN to TMAX, high-Z mode disabled, span compression
disabled, turbo mode enabled, and sampling frequency fS = 2 MSPS for the AD4003, fS = 1 MSPS for the AD4007, and fS = 500 kSPS for
the AD4011, unless otherwise noted.
Table 1.
Parameter
RESOLUTION
ANALOG INPUT
Voltage Range
Operating Input Voltage
Common-Mode Input Range
Common-Mode Rejection Ratio (CMRR)
Analog Input Current
Test Conditions/Comments
Min
18
IN+ voltage (VIN+) − IN− voltage
(VIN−)
Span compression enabled
VIN+, VIN− to GND
Span compression enabled
THROUGHPUT
Complete Cycle
AD4003
AD4007
AD4011
Conversion Time
Acquisition Phase1
AD4003
AD4007
AD4011
Throughput Rate2
AD4003
AD4007
AD4011
Transient Response3
DC ACCURACY
No Missing Codes
Integral Nonlinearity Error (INL)
Differential Nonlinearity Error (DNL)
Transition Noise
Zero Error
Zero Error Drift4
Gain Error
Gain Error Drift4
Power Supply Sensitivity
1/f Noise5
Max
Unit
Bits
−VREF
+VREF
V
−VREF × 0.8
−0.1
0.1 × VREF
VREF/2 − 0.125
+VREF × 0.8
VREF + 0.1
0.9 × VREF
VREF/2 + 0.125
V
V
V
V
dB
nA
μA
fIN = 500 kHz
Acquisition phase, T = 25°C
High-Z mode enabled, converting
dc input at 2 MSPS
500
1000
2000
270
Typ
VREF/2
68
0.3
1
290
320
290
790
1790
ns
ns
ns
0
0
0
2
1
500
250
18
−1.0
−3.8
−0.75
−7
−0.21
−26
−1.23
VDD = 1.8 V ± 5%
Bandwidth = 0.1 Hz to 10 Hz
Rev. B | Page 4 of 38
ns
ns
ns
ns
±0.4
±1.52
±0.3
0.8
±3
1.5
6
+1.0
+3.8
+0.75
+7
+0.21
+26
+1.23
MSPS
MSPS
kSPS
ns
Bits
LSB
ppm
LSB
LSB
LSB
ppm/°C
LSB
ppm/°C
LSB
μV p-p
Data Sheet
Parameter
AC ACCURACY
Dynamic Range
Total RMS Noise
fIN = 1 kHz, −0.5 dBFS, VREF = 5 V
Signal-to-Noise Ratio (SNR)
Spurious-Free Dynamic Range (SFDR)
Total Harmonic Distortion (THD)
Signal-to-Noise-and-Distortion Ratio
(SINAD)
Oversampled Dynamic Range
fIN = 1 kHz, −0.5 dBFS, VREF = 2.5 V
SNR
SFDR
THD
SINAD
fIN = 100 kHz, −0.5 dBFS, VREF = 5 V
SNR
THD
SINAD
fIN = 400 kHz, −0.5 dBFS, VREF = 5 V
SNR
THD
SINAD
−3 dB Input Bandwidth
Aperture Delay
Aperture Jitter
REFERENCE
Voltage Range, VREF
Current
AD4003
AD4007
AD4011
INPUT OVERVOLTAGE CLAMP
IN+/IN− Current, IIN+/IIN−
VIN+/VIN− at Maximum IIN+/IIN−
VIN+/VIN− Clamp On/Off Threshold
Deactivation Time
REF Current at Maximum IIN+/IIN−
DIGITAL INPUTS
Logic Levels
Input Low Voltage, VIL
Input High Voltage, VIH
AD4003/AD4007/AD4011
Test Conditions/Comments
Min
99
98.5
Oversampling ratio (OSR) = 256,
VREF = 5 V
93.5
93
Typ
dB
μV rms
100.5
122
−123
100
dB
dB
dB
dB
122
dB
94.5
122
−119
94
dB
dB
dB
dB
99
−100
96.5
dB
dB
dB
91.5
−94
90
10
1
1
dB
dB
dB
MHz
ns
ps rms
5.1
1.1
0.5
0.26
VREF = 5 V
VREF = 2.5 V
VREF = 5 V
VREF = 2.5 V
VREF = 5 V
VREF = 2.5 V
5.25
2.68
VIN+/VIN− > VREF
VIO > 2.7 V
VIO ≤ 2.7 V
VIO > 2.7 V
VIO ≤ 2.7 V
6
Rev. B | Page 5 of 38
V
mA
mA
mA
50
50
mA
mA
V
V
V
V
ns
μA
+0.3 × VIO
+0.2 × VIO
VIO + 0.3
VIO + 0.3
+1
+1
V
V
V
V
μA
μA
pF
5.4
3.1
5.4
2.8
360
100
−0.3
−0.3
0.7 × VIO
0.8 × VIO
−1
−1
Input Low Current, IIL
Input High Current, IIH
Input Pin Capacitance
Unit
101
31.5
2.4
2 MSPS
1 MSPS
500 kSPS
Max
AD4003/AD4007/AD4011
Data Sheet
Parameter
DIGITAL OUTPUTS
Data Format
Pipeline Delay
Test Conditions/Comments
Min
Output Low Voltage, VOL
Output High Voltage, VOH
POWER SUPPLIES
VDD
VIO
Standby Current
Power Dissipation
ISINK = 500 μA
ISOURCE = −500 μA
Serial 18 bits, twos complement
Conversion results available immediately
after completed conversion
0.4
VIO − 0.3
VDD Only
REF Only
VIO Only
Energy per Conversion
TEMPERATURE RANGE
Specified Performance
1.71
1.71
VDD = 1.8 V, VIO = 1.8 V, T = 25°C
VDD = 1.8 V, VIO = 1.8 V, VREF = 5 V
10 kSPS, high-Z mode disabled
500 kSPS, high-Z mode disabled
1 MSPS, high-Z mode disabled
2 MSPS, high-Z mode disabled
500 kSPS, high-Z mode enabled
1 MSPS, high-Z mode enabled
2 MSPS, high-Z mode enabled
500 kSPS, high-Z mode disabled
1 MSPS, high-Z mode disabled
2 MSPS, high-Z mode disabled
500 kSPS, high-Z mode disabled
1 MSPS, high-Z mode disabled
2 MSPS, high-Z mode disabled
500 kSPS, high-Z mode disabled
1 MSPS, high-Z mode disabled
2 MSPS, high-Z mode disabled
Typ
1.8
Max
1.89
5.5
1.6
80
4
8
16
5
10
20
2.4
4.9
9.5
1.4
2.8
5.5
0.1
0.4
1.0
4.7
9.3
18.5
6.2
12.3
24.5
8
TMIN to TMAX
−40
1
Unit
V
V
V
V
μA
μW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
mW
nJ/sample
+125
°C
The acquisition phase is the time available for the input sampling capacitors to acquire a new input with the ADC running at a throughput rate of 2 MSPS for the
AD4003, 1 MSPS for the AD4007, and 500 kSPS for the AD4011.
2
A throughput rate of 2 MSPS can only be achieved with turbo mode enabled and a minimum SCK rate of 75 MHz. Refer to Table 4 for the maximum achievable
throughput for different modes of operation.
3
Transient response is the time required for the ADC to acquire a full-scale input step to ±1 LSB accuracy.
4
The minimum and maximum values are guaranteed by characterization, but not production tested.
5
See the 1/f noise plot in Figure 23.
Rev. B | Page 6 of 38
Data Sheet
AD4003/AD4007/AD4011
TIMING SPECIFICATIONS
VDD = 1.71 V to 1.89 V; VIO = 1.71 V to 5.5 V; VREF = 5 V; all specifications TMIN to TMAX, high-Z mode disabled, span compression
disabled, turbo mode enabled, and sampling frequency fS = 2 MSPS for the AD4003, fS = 1 MSPS for the AD4007, and fS = 500 kSPS for
the AD4011, unless otherwise noted. See Figure 2 for the timing voltage levels.
Table 2. Digital Interface Timing
Parameter
CONVERSION TIME—CNV RISING EDGE TO DATA AVAILABLE
ACQUISITION PHASE1
AD4003
AD4007
AD4011
TIME BETWEEN CONVERSIONS
AD4003
AD4007
AD4011
CNV PULSE WIDTH (CS MODE)2
Symbol
tCONV
tACQ
Min
270
Typ
290
Max
320
Unit
ns
290
790
1790
ns
ns
ns
500
1000
2000
10
ns
ns
ns
ns
9.8
12.3
ns
ns
20
25
3
3
1.5
ns
ns
ns
ns
ns
tCYC
tCNVH
SCK PERIOD (CS MODE)3
VIO > 2.7 V
VIO > 1.7 V
SCK PERIOD (DAISY-CHAIN MODE)4
VIO > 2.7 V
VIO > 1.7 V
SCK LOW TIME
SCK HIGH TIME
SCK FALLING EDGE TO DATA REMAINS VALID DELAY
SCK FALLING EDGE TO DATA VALID DELAY
VIO > 2.7 V
VIO > 1.7 V
CNV OR SDI LOW TO SDO D17 MOST SIGNIFICANT BIT (MSB) VALID DELAY (CS MODE)
VIO > 2.7 V
VIO > 1.7 V
CNV RISING EDGE TO FIRST SCK RISING EDGE DELAY
LAST SCK FALLING EDGE TO CNV RISING EDGE DELAY5
CNV OR SDI HIGH OR LAST SCK FALLING EDGE TO SDO HIGH IMPEDANCE (CS MODE)
tSCK
tSCK
tSCKL
tSCKH
tHSDO
tDSDO
7.5
10.5
ns
ns
10
13
ns
ns
ns
ns
ns
tEN
tQUIET1
tQUIET2
tDIS
190
60
SDI VALID SETUP TIME FROM CNV RISING EDGE
SDI VALID HOLD TIME FROM CNV RISING EDGE (CS MODE)
tSSDICNV
tHSDICNV
2
2
ns
ns
SCK VALID HOLD TIME FROM CNV RISING EDGE (DAISY-CHAIN MODE)
SDI VALID SETUP TIME FROM SCK RISING EDGE (DAISY-CHAIN MODE)
SDI VALID HOLD TIME FROM SCK RISING EDGE (DAISY-CHAIN MODE)
tHSCKCNV
tSSDISCK
tHSDISCK
12
2
2
ns
ns
ns
1
20
The acquisition phase is the time available for the input sampling capacitors to acquire a new input with the ADC running at a throughput rate of 2 MSPS for the
AD4003, 1 MSPS for the AD4007, and 500 kSPS for the AD4011.
2
For turbo mode, tCNVH must match the tQUIET1 minimum.
3
A throughput rate of 2 MSPS can only be achieved with turbo mode enabled and a minimum SCK rate of 75 MHz. Refer to Table 4 for the maximum achievable
throughput for different modes of operation.
4
A 50% duty cycle is assumed for SCK.
5
See Figure 22 for SINAD vs. tQUIET2.
Rev. B | Page 7 of 38
AD4003/AD4007/AD4011
Data Sheet
Table 3. Register Read/Write Timing
Parameter
READ/WRITE OPERATION
CNV Pulse Width1
SCK Period
VIO > 2.7 V
VIO > 1.7 V
SCK Low Time
SCK High Time
READ OPERATION
CNV Low to SDO D17 MSB Valid Delay
VIO > 2.7 V
VIO > 1.7 V
SCK Falling Edge to Data Remains Valid
SCK Falling Edge to Data Valid Delay
VIO > 2.7 V
VIO > 1.7 V
CNV Rising Edge to SDO High Impedance
WRITE OPERATION
SDI Valid Setup Time from SCK Rising Edge
SDI Valid Hold Time from SCK Rising Edge
CNV Rising Edge to SCK Edge Hold Time
CNV Falling Edge to SCK Active Edge Setup Time
Min
tCNVH
tSCK
10
ns
9.8
12.3
3
3
ns
ns
ns
ns
tSCKL
tSCKH
Typ
Max
Unit
tEN
tHSDO
tDSDO
ns
ns
ns
7.5
10.5
20
ns
ns
ns
1.5
tDIS
tSSDISCK
tHSDISCK
tHCNVSCK
tSCNVSCK
10
13
2
2
0
6
ns
ns
ns
ns
For turbo mode, tCNVH must match the tQUIET1 minimum.
Y% VIO1
X% VIO1
tDELAY
tDELAY
VIH2
VIL2
VIH2
VIL2
1FOR VIO ≤ 2.7V, X = 80, AND Y = 20; FOR VIO > 2.7V, X = 70, AND Y = 30.
2MINIMUM V AND MAXIMUM V USED. SEE DIGITAL INPUTS
IH
IL
SPECIFICATIONS IN TABLE 1.
14957-002
1
Symbol
Figure 2. Voltage Levels for Timing
Table 4. Achievable Throughput for Different Modes of Operation
Parameter
THROUGHPUT, CS MODE
3-Wire and 4-Wire Turbo Mode
3-Wire and 4-Wire Turbo Mode and Six Status Bits
3-Wire and 4-Wire Mode
3-Wire and 4-Wire Mode and Six Status Bits
Test Conditions/Comments
fSCK = 100 MHz, VIO ≥ 2.7 V
fSCK = 80 MHz, VIO < 2.7 V
fSCK = 100 MHz, VIO ≥ 2.7 V
fSCK = 80 MHz, VIO < 2.7 V
fSCK = 100 MHz, VIO ≥ 2.7 V
fSCK = 80 MHz, VIO < 2.7 V
fSCK = 100 MHz, VIO ≥ 2.7 V
fSCK = 80 MHz, VIO < 2.7 V
Rev. B | Page 8 of 38
Min
Typ
Max
Unit
2
2
2
1.78
1.75
1.62
1.59
1.44
MSPS
MSPS
MSPS
MSPS
MSPS
MSPS
MSPS
MSPS
Data Sheet
AD4003/AD4007/AD4011
ABSOLUTE MAXIMUM RATINGS
Note that the input overvoltage clamp cannot sustain the
overvoltage condition for an indefinite amount of time.
THERMAL RESISTANCE
Thermal performance is directly linked to printed circuit board
(PCB) design and operating environment. Careful attention to
PCB thermal design is required.
Table 5.
Parameter
Analog Inputs
IN+, IN− to GND1
Supply Voltage
REF, VIO to GND
VDD to GND
VDD to VIO
Digital Inputs to GND
Digital Outputs to GND
Storage Temperature Range
Junction Temperature
Lead Temperature Soldering
Electrostatic Discharge (ESD) Ratings
Human Body Model (HBM)
Machine Model
Field Induced Charged Device Model
1
2
Rating
Table 6. Thermal Resistance
−0.3 V to VREF + 0.4 V
or ± 130 mA2
−0.3 V to +6.0 V
−0.3 V to +2.1 V
−6 V to +2.4 V
−0.3 V to VIO + 0.3 V
−0.3 V to VIO + 0.3 V
−65°C to +150°C
150°C
260°C reflow as per
JEDEC J-STD-020
Package Type1
RM-10
CP-10-9
1
θJA2
147
114
θJC3
38
33
Unit
°C/W
°C/W
Test Condition 1: thermal impedance simulated values are based upon use
of 2S2P JEDEC PCB. See the Ordering Guide.
2
θJA is the natural convection junction to ambient thermal resistance
measured in a one cubic foot sealed enclosure.
3
θJC is the junction to case thermal resistance.
ESD CAUTION
4 kV
200 V
1.25 kV
See the Analog Inputs section for an explanation of IN+ and IN−.
Current condition tested over a 10 ms time interval.
Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.
Rev. B | Page 9 of 38
AD4003/AD4007/AD4011
Data Sheet
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
REF 1
IN+ 3
10 VIO
IN+ 3
AD4003/
AD4007
IN– 4
TOP VIEW
(Not to Scale)
VDD 2
GND 5
9
SDI
8
SCK
7
SDO
6
CNV
GND 5
TOP VIEW
(Not to Scale)
9
SDI
8
SCK
7
SDO
6
CNV
NOTES
1. CONNECT THE EXPOSED PAD TO GND.
THIS CONNECTION IS NOT REQUIRED TO
MEET THE SPECIFIED PERFORMANCE.
14957-003
REF 1
IN– 4
10 VIO
AD4003/
AD4007/
AD4011
Figure 3. 10-Lead MSOP Pin Configuration
14957-004
VDD 2
Figure 4. 10-Lead LFCSP Pin Configuration
Table 7. Pin Function Descriptions
Pin No.
1
Mnemonic
REF
Type1
AI
2
VDD
P
3
4
5
6
IN+
IN−
GND
CNV
AI
AI
P
DI
7
8
9
SDO
SCK
SDI
DO
DI
DI
10
VIO
P
N/A2
EPAD
P
1
2
Description
Reference Input Voltage. The VREF range is 2.4 V to 5.1 V. This pin is referred to the GND pin and must be
decoupled closely to the GND pin with a 10 μF X7R ceramic capacitor.
1.8 V Power Supply. The VDD range is 1.71 V to 1.89 V. Bypass VDD to GND with a 0.1 μF ceramic
capacitor.
Differential Positive Analog Input. See the Differential Input Considerations section.
Differential Negative Analog Input. See the Differential Input Considerations section.
Power Supply Ground.
Convert Input. This input has multiple functions. On its leading edge, it initiates the conversions and
selects the interface mode of the device: daisy-chain mode or CS mode. In CS mode, the SDO pin is
enabled when CNV is low. In daisy-chain mode, the data is read when CNV is high.
Serial Data Output. The conversion result is output on this pin. It is synchronized to SCK.
Serial Data Clock Input. When the device is selected, the conversion result is shifted out by this clock.
Serial Data Input. This input provides multiple features. It selects the interface mode of the ADC as
follows:
Daisy-chain mode is selected if SDI is low during the CNV rising edge. In this mode, SDI is used as a data
input to daisy-chain the conversion results of two or more ADCs onto a single SDO line. The digital data
level on SDI is output on SDO with a delay of 18 SCK cycles.
CS mode is selected if SDI is high during the CNV rising edge. In this mode, either SDI or CNV can enable
the serial output signals when low. If SDI or CNV is low when the conversion is complete, the busy
indicator feature is enabled. With CNV low, the device can be programmed by clocking in a 16-bit word
on SDI on the rising edge of SCK.
Input/Output Interface Digital Power. Nominally, this pin is at the same supply as the host interface (1.8 V,
2.5 V, 3 V, or 5 V). Bypass VIO to GND with a 0.1 μF ceramic capacitor.
Exposed Pad (LFCSP Only). Connect the exposed pad to GND. This connection is not required to meet
the specified performance.
AI is analog input, P is power, DI is digital input, and DO is digital output.
N/A means not applicable.
Rev. B | Page 10 of 38
Data Sheet
AD4003/AD4007/AD4011
TYPICAL PERFORMANCE CHARACTERISTICS
VDD = 1.8 V; VIO = 3.3 V; VREF = 5 V; T = 25°C, high-Z mode disabled, span compression disabled, turbo mode enabled, and sampling
frequency fS = 2 MSPS for the AD4003, fS = 1 MSPS for the AD4007, and fS = 500 kSPS for the AD4011, unless otherwise noted.
0.4
1.0
0.8
+125°C
+25°C
–40°C
0.6
+125°C
+25°C
–40°C
0.3
0.2
0.2
DNL (LSB)
INL (LSB)
0.4
0
–0.2
0.1
0
–0.1
–0.4
–0.2
–0.6
0
32768
65536
98304 131072 163840 196608 229376 262144
CODE
–0.4
14957-200
–1.0
Figure 5. INL vs. Code for Various Temperatures, VREF = 5 V
0
32768
65536
98304 131072 163840 196608 229376 262144
CODE
14957-203
–0.3
–0.8
Figure 8. DNL vs. Code for Various Temperatures, VREF = 5 V
0.4
1.0
0.8
+125°C
+25°C
–40°C
0.6
0.3
0.2
0.2
DNL (LSB)
INL (LSB)
0.4
0
–0.2
0.1
0
–0.1
–0.4
–0.2
–0.6
32768
65536
98304 131072 163840 196608 229376 262144
CODE
–0.4
Figure 6. INL vs. Code for Various Temperatures, VREF = 2.5 V
0
32768
65536
98304 131072 163840 196608 229376 262144
CODE
Figure 9. DNL vs. Code for Various Temperatures, VREF = 2.5 V
1.8
0.8
1.7
0.6
+125°C
+25°C
–40°C
1.6
TRANSITION NOISE (LSB)
0.4
0
–0.2
–0.4
1.5
1.4
1.3
1.2
1.1
1.0
–0.6
0.9
HIGH-Z ENABLED
SPAN COMPRESSION ENABLED
32768
65536
98304 131072 163840 196608 229376 262144
CODE
0.8
2.5
14957-202
0
Figure 7. INL vs. Code, High-Z and Span Compression Modes Enabled, VREF = 5 V
3.0
3.5
4.0
REFERENCE VOLTAGE (V)
4.5
5.0
14957-206
INL (LSB)
0.2
–0.8
14957-204
0
14957-201
–1.0
+125°C
+25°C
–40°C
–0.3
–0.8
Figure 10. Transition Noise vs. Reference Voltage for Various Temperatures
Rev. B | Page 11 of 38
AD4003/AD4007/AD4011
Data Sheet
4.5M
3.0M
3.0M
CODE
131073
131074
131075
131076
131077
VREF = 2.5V
SNR = 95.01dB
THD = –118.60dB
SINAD = 94.99dB
–20
FUNDAMENTAL AMPLITUDE (dB)
–60
–80
–100
–120
–140
–40
–60
–80
–100
–120
–140
10k
100k
1M
FREQUENCY (Hz)
–180
100
14957-207
1k
1k
10k
100k
1M
FREQUENCY (Hz)
14957-209
–160
–160
Figure 15. 1 kHz, −0.5 dBFS Input Tone FFT, Wide View, VREF = 2.5 V
Figure 12. 1 kHz, −0.5 dBFS Input Tone Fast Fourier Transform (FFT), Wide
View, VREF = 5 V
0
0
VREF = 5V
SNR = 98.37dB
THD = –98.52dB
SINAD = 95.58dB
FUNDAMENTAL AMPLITUDE (dB)
–20
–60
–80
–100
–120
–140
–40
VREF = 5V
SNR = 91.22dB
THD = –91.97dB
SINAD = 89.15dB
–60
–80
–100
–120
–140
–160
10k
100k
FREQUENCY (Hz)
1M
14957-210
–160
–180
1k
10k
100k
FREQUENCY (Hz)
Figure 16. 400 kHz, −0.5 dBFS Input Tone FFT, Wide View
Figure 13. 100 kHz, −0.5 dBFS Input Tone FFT, Wide View
Rev. B | Page 12 of 38
1M
14957-213
FUNDAMENTAL AMPLITUDE (dB)
–40
–180
1k
131071
131072
0
VREF = 5V
SNR = 100.33dB
THD = –123.99dB
SINAD = 100.31dB
–20
–40
131069
131070
CODE
Figure 14. Histogram of a DC Input at Code Transition, VREF = 2.5 V and
VREF = 5 V
0
–20
131067
131068
14957-205
131080
131081
131078
131079
0
131075
131076
131077
0
131073
131074
0.5M
131071
131072
0.5M
131069
131070
1.0M
131067
131068
1.0M
131065
131066
1.5M
131063
131064
1.5M
Figure 11. Histogram of a DC Input at Code Center, VREF = 2.5 V and VREF = 5 V
FUNDAMENTAL AMPLITUDE (dB)
2.0M
131065
131066
2.0M
2.5M
131063
131064
2.5M
131062
CODE COUNT
3.5M
131062
CODE COUNT
3.5M
–180
100
VREF = 2.5V
VREF = 5V
4.0M
14957-208
VREF = 2.5V
VREF = 5V
4.0M
131078
131079
131080
131081
4.5M
Data Sheet
AD4003/AD4007/AD4011
132
–118
16.2
16.0
98
97
131
–120
THD (dB)
99
ENOB (Bits)
SNR, SINAD (dB)
100
–116
130
–122
129
–124
15.8
96
128
–126
15.6
ENOB
SINAD
SNR
94
2.4
2.7
3.0
3.3
3.6
3.9
4.2
4.5
4.8
SFDR
THD
–128
15.4
5.1
–130
2.4
14957-219
95
REFERENCE VOLTAGE (V)
2.7
3.9
4.2
4.5
126
5.1
4.8
118.0
THD
SFDR
–114.5
117.9
16.38
100.4
117.8
–115.0
16.36
16.32
100.0
16.30
THD (dB)
16.34
100.2
ENOB (Bits)
SNR, SINAD (dB)
3.6
–114.0
16.40
ENOB
SINAD
SNR
3.3
Figure 20. THD and SFDR vs. Reference Voltage
16.42
100.6
3.0
127
REFERENCE VOLTAGE (V)
Figure 17. SNR, SINAD, and Effective Number of Bits (ENOB) vs. Reference
Voltage
100.8
16.28
99.8
117.7
117.6
–115.5
117.5
–116.0
117.4
117.3
–116.5
16.26
99.6
117.2
–117.0
16.24
–20
0
20
40
60
80
100
120
16.22
14957-222
99.4
–40
TEMPERATURE (°C)
–20
0
20
40
60
80
100
120
117.0
TEMPERATURE (°C)
Figure 21. THD and SFDR vs. Temperature, fIN = 1 kHz
101
DYNAMIC RANGE
fIN = 1kHz
fIN = 10kHz
130
117.1
–117.5
–40
Figure 18. SNR, SINAD, and ENOB vs. Temperature, fIN = 1 kHz
135
SFDR (dB)
16.4
133
SFDR (dB)
101
–114
14957-216
16.6
14957-225
102
100
125
99
SINAD (dB)
SNR (dB)
120
115
110
98
97
105
2
4
8
16
32
64
DECIMATION RATE
128
256
512 1024
Figure 19. SNR vs. Decimation Rate for Various Input Frequencies, 2 MSPS
Rev. B | Page 13 of 38
95
0
10
20
30
40
50
tQUIET2 (ns)
Figure 22. SINAD vs. tQUIET2
60
70
80
14957-215
1
14957-212
95
VIO = 1.89V
VIO = 3.6V
VIO = 5.5V
96
100
AD4003/AD4007/AD4011
Data Sheet
60
10
57
56
1
2
3
4
5
6
7
8
9
10
TIME (Seconds)
Figure 23. 1/f Noise for 0.1 Hz to 10 Hz Bandwidth, 50 kSPS, 2500 Samples
Averaged per Reading
0
–2
–4
–6
–8
–10
–40
4.5
7
4.0
5
VDD HIGH-Z DISABLED
VDD HIGH-Z ENABLED
REF HIGH-Z DISABLED
REF HIGH-Z ENABLED
VIO HIGH-Z DISABLED
VIO HIGH-Z ENABLED
4
3
2
1
0
20
40
60
80
100
120
100
120
3.0
2.5
2.0
VDD HIGH-Z ENABLED
VDD HIGH-Z DISABLED
REF HIGH-Z ENABLED
REF HIGH-Z DISABLED
VIO HIGH-Z ENABLED
VIO HIGH-Z DISABLED
1.5
1.0
–20
0
20
40
60
80
100
120
Figure 27. Operating Current vs. Temperature, AD4007, 1 MSPS
1.2
2MSPS
1MSPS
500kSPS
1.0
REFERENCE CURRENT (mA)
2.0
1.5
VDD HIGH-Z ENABLED
VDD HIGH-Z DISABLED
REF HIGH-Z ENABLED
REF HIGH-Z DISABLED
VIO HIGH-Z ENABLED
VIO HIGH-Z DISABLED
0.8
0.6
0.4
0.2
–20
0
20
40
60
80
100
120
TEMPERATURE (°C)
14957-325
OPERATING CURRENT (mA)
80
TEMPERATURE (°C)
2.5
0
–40
60
3.5
0
–40
Figure 24. Operating Current vs. Temperature, AD4003, 2 MSPS
0.5
40
14957-326
–20
TEMPERATURE (°C)
1.0
20
0.5
14957-223
0
–40
0
Figure 26. Zero Error and Gain Error vs. Temperature Positive Full Scale (PFS)
and Negative Full Scale (NFS)
8
6
–20
TEMPERATURE (°C)
OPERATING CURRENT (mA)
OPERATING CURRENT (mA)
2
Figure 25. Operating Current vs. Temperature, AD4011, 500 kSPS
0
2.4
2.7
3.0
3.3
3.6
3.9
4.2
4.5
4.8
REFERENCE VOLTAGE (V)
Figure 28. Reference Current vs. Reference Voltages
Rev. B | Page 14 of 38
5.1
14957-218
0
4
14957-217
55
PFS GAIN ERROR
NFS GAIN ERROR
ZERO ERROR
6
14957-221
58
54
8
ZERO ERROR AND GAIN ERROR (LSB)
ADC OUTPUT READING (µV)
59
Data Sheet
AD4003/AD4007/AD4011
25.0
23
22.5
21
17.5
17
tDSDO (ns)
15.0
12.5
10.0
15
13
11
7.5
9
5.0
–20
0
20
40
60
80
100
TEMPERATURE (°C)
120
Figure 29. Standby Current vs. Temperature
5
0
20
40
60
80
100
120
140
160
LOAD CAPACITANCE (pF)
Figure 30. tDSDO vs. Load Capacitance
Rev. B | Page 15 of 38
180
200
220
14957-224
7
2.5
0
–40
VIO = 5V
VIO = 3.3V
VIO = 1.8V
19
14957-226
STANDBY CURRENT (µA)
20.0
AD4003/AD4007/AD4011
Data Sheet
TERMINOLOGY
Integral Nonlinearity Error (INL)
INL is the deviation of each individual code from a line drawn
from negative full scale through positive full scale. The point
used as negative full scale occurs ½ LSB before the first code
transition. Positive full scale is defined as a level 1½ LSB beyond
the last code transition. The deviation is measured from the
middle of each code to the true straight line (see Figure 32).
Differential Nonlinearity Error (DNL)
In an ideal ADC, code transitions are 1 LSB apart. DNL is the
maximum deviation from this ideal value. It is often specified in
terms of resolution for which no missing codes are guaranteed.
Zero Error
Zero error is the difference between the ideal midscale voltage,
0 V, and the actual voltage producing the midscale output code,
0 LSB.
Gain Error
The first transition (from 100 ... 00 to 100 ... 01) occurs at a level
½ LSB above nominal negative full scale (−4.999981 V for the
±5 V range). The last transition (from 011 … 10 to 011 … 11)
occurs for an analog voltage 1½ LSB below the nominal full
scale (+4.999943 V for the ±5 V range). The gain error is the
deviation of the difference between the actual level of the last
transition and the actual level of the first transition from the
difference between the ideal levels.
Spurious-Free Dynamic Range (SFDR)
SFDR is the difference, in decibels (dB), between the rms
amplitude of the input signal and the peak spurious signal.
Dynamic Range
Dynamic range is the ratio of the rms value of the full scale to
the total rms noise measured. The value for dynamic range is
expressed in decibels. It is measured with a signal at −60 dBFS
so that it includes all noise sources and DNL artifacts.
Signal-to-Noise Ratio (SNR)
SNR is the ratio of the rms value of the actual input signal to the
rms sum of all other spectral components below the Nyquist
frequency, excluding harmonics and dc. The value for SNR is
expressed in decibels.
Signal-to-Noise-and-Distortion Ratio (SINAD)
SINAD is the ratio of the rms value of the actual input signal to
the rms sum of all other spectral components that are less than
the Nyquist frequency, including harmonics but excluding dc.
The value of SINAD is expressed in decibels.
Aperture Delay
Aperture delay is the measure of the acquisition performance
and is the time between the rising edge of the CNV input and
when the input signal is held for a conversion.
Transient Response
Transient response is the time required for the ADC to acquire a
full-scale input step to ±1 LSB accuracy.
Common-Mode Rejection Ratio (CMRR)
CMRR is the ratio of the power in the ADC output at the
frequency, f, to the power of a 200 mV p-p sine wave applied to
the common-mode voltage of IN+ and IN− of frequency, f.
CMRR (dB) = 10log(PADC_IN/PADC_OUT)
Effective Number of Bits (ENOB)
ENOB is a measurement of the resolution with a sine wave
input. It is related to SINAD as follows:
where:
PADC_IN is the common-mode power at the frequency, f, applied
to the IN+ and IN− inputs.
PADC_OUT is the power at the frequency, f, in the ADC output.
ENOB = (SINADdB − 1.76)/6.02
ENOB is expressed in bits.
Total Harmonic Distortion (THD)
THD is the ratio of the rms sum of the first five harmonic
components to the rms value of a full-scale input signal and is
expressed in decibels.
Power Supply Rejection Ratio (PSRR)
PSRR is the ratio of the power in the ADC output at the
frequency, f, to the power of a 200 mV p-p sine wave applied to
the ADC VDD supply of frequency, f.
PSRR (dB) = 10 log(PVDD_IN/PADC_OUT)
where:
PVDD_IN is the power at the frequency, f, at the VDD pin.
PADC_OUT is the power at the frequency, f, in the ADC output.
Rev. B | Page 16 of 38
Data Sheet
AD4003/AD4007/AD4011
THEORY OF OPERATION
IN+
SWITCHES CONTROL
LSB
MSB
REF
GND
131,072C
65,536C
4C
2C
C
SW+
C
BUSY
COMP
131,072C
65,536C
4C
2C
C
CONTROL
LOGIC
C
MSB
OUTPUT CODE
LSB
SW–
14957-007
CNV
IN–
Figure 31. ADC Simplified Schematic
CIRCUIT INFORMATION
The AD4003/AD4007/AD4011 are high speed, low power,
single-supply, precise, 18-bit ADCs based on a SAR architecture.
frequencies as well as improved distortion over a wide frequency
range up to 100 kHz. For frequencies greater than 100 kHz and
multiplexing, disable high-Z mode.
For single-supply applications, a span compression feature
creates additional headroom and footroom for the driving
amplifier to access the full range of the ADC.
The AD4003 is capable of converting 2,000,000 samples per
second (2 MSPS), the AD4007 is capable of converting 1,000,000
samples per second (1 MSPS), and the AD4011 is capable of
converting 500,000 samples per second (500 kSPS). The power
consumption of the AD4003/AD4007/AD4011 scales with
throughput, because they power down in between conversions.
When operating at 10 kSPS, for example, they typically
consume 80 μW, making them ideal for battery-powered
applications. The AD4003/ AD4007/AD4011 also have a valid
first conversion after being powered down for long periods,
which can further reduce power consumed in applications in
which the ADC does not need to be constantly converting.
The AD4003/AD4007/AD4011 can interface with any 1.8 V to 5 V
digital logic family. They are available in a 10-lead MSOP or a tiny
10-lead LFCSP that allows space savings and flexible configurations.
The AD4003/AD4007/AD4011 provide the user with an
on-chip, track-and-hold and do not exhibit any pipeline delay
or latency, making them ideal for multiplexed applications.
The AD4003/AD4007/AD4011 are pin for pin compatible
with some of the 14-/16-/18-/20-bit precision SAR ADCs listed
in Table 8.
The AD4003/AD4007/AD4011 incorporate a multitude of
unique ease of use features that result in a lower system power
and footprint.
Table 8. MSOP, LFCSP 14-/16-/18-/20-Bit Precision SAR ADCs
The AD4003/AD4007/AD4011 each have an internal voltage
clamp that protects the device from overvoltage damage on the
analog inputs.
The analog input incorporates circuitry that reduces the nonlinear
charge kickback seen from a typical switched capacitor SAR input.
This reduction in kickback, combined with a longer acquisition
phase, means reduced settling requirements on the driving
amplifier. This combination allows the use of lower bandwidth
and lower power amplifiers as drivers. It has the additional benefit
of allowing a larger resistor value in the input RC filter and a
corresponding smaller capacitor, which results in a smaller RC
load for the amplifier, improving stability and power dissipation.
High-Z mode can be enabled via the SPI interface by programming
a register bit (see Table 14). When high-Z mode is enabled, the
ADC input has a low input charging current at low input signal
The fast conversion time of the AD4003/AD4007/AD4011, along
with turbo mode, allows low clock rates to read back conversions,
even when running at their respective maximum throughput
rates. Note that for the AD4003, the full throughput rate of
2 MSPS can be achieved only with turbo mode enabled.
400 kSPS to
500 kSPS
Bits 100 kSPS
201
181 AD7989-12
250 kSPS
AD76912
AD76902,
AD7989-52
161
AD7684
AD76872
163
AD7680,
AD7683,
AD7988-12
AD76852,
AD7694
AD76882,
AD76932,
AD79162
AD76862,
AD7988-52
AD40082
143
AD7940
AD79422
1
True differential.
Pin for pin compatible.
3
Pseudo differential.
2
Rev. B | Page 17 of 38
AD79462
≥1000 kSPS
AD40202
AD40032,
AD79822,
AD79842,
AD40072,
AD40112
AD4001,
AD4005,
AD79152
AD40002,
AD40042,
AD79802,
AD7983
Not applicable
AD4003/AD4007/AD4011
Data Sheet
During the acquisition phase, terminals of the array tied to the
input of the comparator are connected to GND via the SW+ and
SW− switches. All independent switches connect the other
terminal of each capacitor to the analog inputs. Therefore, the
capacitor arrays are used as sampling capacitors and acquire the
analog signal on the IN+ and IN− inputs.
When the acquisition phase is complete and the CNV input
goes high, a conversion phase initiates. When the conversion
phase begins, SW+ and SW− are opened first. The two capacitor
arrays are then disconnected from the inputs and connected to
the GND input. The differential voltage between the IN+ and
IN− inputs captured at the end of the acquisition phase is applied
to the comparator inputs, causing the comparator to become
unbalanced. By switching each element of the capacitor array
between GND and VREF, the comparator input varies by binary
weighted voltage steps (VREF/2, VREF/4, …, VREF/262,144). The
control logic toggles these switches, starting with the MSB, to
bring the comparator back into a balanced condition. After the
Because the AD4003, AD4007, and AD4011 have on-board
conversion clocks, the serial clock (SCK) is not required for the
conversion process.
TRANSFER FUNCTIONS
The ideal transfer characteristics for the AD4003/AD4007/
AD4011 are shown in Figure 32 and Table 9.
011...111
011...110
011...101
100...010
100...001
100...000
–FSR
–FSR + 1 LSB
–FSR + 0.5 LSB
+FSR – 1 LSB
+FSR – 1.5 LSB
ANALOG INPUT
14957-008
The AD4003/AD4007/AD4011 are SAR-based ADCs using a
charge redistribution sampling digital-to-analog converter
(DAC). Figure 31 shows the simplified schematic of the ADC.
The capacitive DAC consists of two identical arrays of 18 binary
weighted capacitors, which are connected to the comparator inputs.
completion of this process, the control logic generates the ADC
output code and a busy signal indicator.
ADC CODE (TWOS COMPLEMENT)
CONVERTER OPERATION
Figure 32. ADC Ideal Transfer Function (FSR Is Full-Scale Range)
Table 9. Output Codes and Ideal Input Voltages
Description
FSR − 1 LSB
Midscale + 1 LSB
Midscale
Midscale − 1 LSB
−FSR + 1 LSB
−FSR
Analog Input, VREF = 5 V
+4.999962 V
+38.15 μV
0V
−38.15 μV
−4.999962 V
−5 V
VREF = 5 V with Span Compression Enabled
+3.999969 V
+30.5 μV
0V
−30.5 μV
−3.999969 V
−4 V
1
Digital Output Code (Hex)
0x1FFFF1
0x00001
0x00000
0x3FFFF
0x20001
0x200002
This output code is also the code for an overranged analog input (VIN+ − VIN− above VREF with the span compression disabled and above 0.8 ×VREF with the span
compression enabled).
2
This output code is also the code for an underranged analog input (VIN+ − VIN− below −VREF with the span compression disabled and above 0.8 ×VREF with the span
compression enabled).
Rev. B | Page 18 of 38
Data Sheet
AD4003/AD4007/AD4011
APPLICATIONS INFORMATION
Figure 34 shows a recommended connection diagram when
using a single-supply system. This setup is preferable when only
a limited number of rails are available in the system and power
dissipation is of critical importance.
TYPICAL APPLICATION DIAGRAMS
Figure 33 shows an example of the recommended connection
diagram for the AD4003/AD4007/AD4011 when multiple supplies
are available. This configuration is used for best performance
because the amplifier supplies can be selected to allow the
maximum signal range.
Figure 35 shows a recommended connection diagram when
using a fully differential amplifier.
V+ ≥ +6.5V
REF
LDO
1.8V
AMP
VCM = VREF /2
5V
10kΩ
0.1µF
10kΩ
V+
AMP
VREF
REF
C
VDD
VIO
SDI
IN+
V–
V+
VCM = VREF/2
AD4003/
AD4007/
AD4011
IN–
R
AMP
SCK
DIGITAL HOST
(MICROPROCESSOR/
FPGA)
SDO
CNV
GND
3-WIRE/4-WIRE
INTERFACE
C
0V
HOST
SUPPLY
R
0V
VREF
1.8V TO 5V
V–
14957-009
VCM = VREF/2
0.1µF
10µF
V– ≤ –0.5V
Figure 33. Typical Application Diagram with Multiple Supplies
V+ = 5V
REF1
LDO
AMP
VCM = VREF /2
4.096V
1.8V
10kΩ
10kΩ
AMP
0.9 × VREF
VCM = VREF /2
0.1 × VREF
0.1µF
0.1µF
100nF
100nF
R
REF
C
VDD
SDI
AD4003/AD4007/
AD40112
IN–
AMP
0.9 × VREF
VCM = VREF /2
0.1 × VREF
HOST
SUPPLY
VIO
IN+
R
1.8V TO 5V
10µF1
GND
SCK
SDO
DIGITAL HOST
(MICROPROCESSOR/
FPGA)
CNV
3-WIRE/4-WIRE
INTERFACE
C
1 SEE THE VOLTAGE REFERENCE INPUT SECTION FOR REFERENCE SELECTION. C
REF IS USUALLY A 10µF CERAMIC CAPACITOR (X7R).
2 SPAN COMPRESSION MODE ENABLED.
3 SEE TABLE 10 FOR RC FILTER AND AMPLIFIER SELECTION.
Figure 34. Typical Application Diagram with a Single Supply
Rev. B | Page 19 of 38
14957-010
3
AD4003/AD4007/AD4011
Data Sheet
V+ = 5V
REF
LDO
AMP
VCM = VREF /2
VCM = VREF/2
R4
1kΩ
R3
1kΩ
VREF
10kΩ
0
4.096V
1.8V
1.8V TO 5V
0.1µF 0.1µF
10kΩ
10µF
HOST
SUPPLY
V+
+IN
VOCM
–IN
SCK
SDO
3-WIRE/4-WIRE
INTERFACE
14957-011
0
DIGITAL HOST
(MICROPROCESSOR/
FPGA)
CNV
GND
V–
R1
1kΩ
VREF
SDI
IN–
R
DIFFERENTIAL
AMPLIFIER
VIO
AD4003/AD4007/
AD4011
C
+OUT
0.1µF
VDD
IN+
C
VCM = VREF/2
VCM = VREF/2
REF
R
–OUT
R2
1kΩ
Figure 35. Typical Application Diagram with a Fully Differential Amplifier
V+ = 5V
REF
LDO
AMP
0V
VCM = VREF /2
R4
1kΩ
R3
1kΩ
+VREF
10kΩ
–V REF
4.096V
10kΩ
10µF
1.8V
0.1µF
0.1µF
1.8V TO 5V
HOST
SUPPLY
V+
+IN
–OUT
REF
R
C
VREF/2
VOCM
–IN
C
+OUT
0.1µF
R
DIFFERENTIAL
AMPLIFIER
VDD
VIO
SDI
IN+
AD4003/AD4007/
AD4011
IN–
GND
SCK
SDO
DIGITAL HOST
(MICROPROCESSOR/
FPGA)
CNV
3-WIRE/4-WIRE
INTERFACE
V–
14957-012
R1
1kΩ
R2
1kΩ
Figure 36. Typical Application Diagram for Single-Ended to Differential Conversion with a Fully Differential Amplifier
ANALOG INPUTS
Input Overvoltage Clamp Circuit
Figure 37 shows an equivalent circuit of the analog input
structure, including the overvoltage clamp of the AD4003/
AD4007/AD4011.
Most ADC analog inputs, IN+ and IN−, have no overvoltage
protection circuitry apart from ESD protection diodes. During
an overvoltage event, an ESD protection diode from an analog
input pin (IN+ or IN−) pin to REF forward biases and shorts
the input pin to REF, potentially overloading the reference or
causing damage to the device. The AD4003/AD4007/AD4011
internal overvoltage clamp circuit with a larger external resistor
(REXT = 200 Ω) eliminates the need for external protection
diodes and protects the ADC inputs against dc overvoltages.
REF
D1
VIN
REXT
RIN CIN
IN+/IN–
CEXT
CPIN
D2
CLAMP
GND
14957-013
0V TO 15V
Figure 37. Equivalent Analog Input Circuit
Rev. B | Page 20 of 38
Data Sheet
AD4003/AD4007/AD4011
When the clamp is active, it sets the overvoltage (OV) clamp flag
bit in the register that can be read back (see Table 14), which is
a sticky bit that must be read to be cleared. The status of the
clamp can also be checked in the status bits using the OV clamp
flag (see Table 15). The clamp circuit does not dissipate static
power in the off state. Note that the clamp cannot sustain the
overvoltage condition for an indefinite amount of time.
The external RC filter is usually present at the ADC input to
band limit the input signal. During an overvoltage event,
excessive voltage is dropped across REXT and REXT becomes part
of a protection circuit. The REXT value can vary from 200 Ω to
20 kΩ for 15 V protection. The CEXT value can be as low as 100
pF for correct operation of the clamp. See Table 1 for input
overvoltage clamp specifications.
Differential Input Considerations
The analog input structure allows the sampling of the true
differential signal between IN+ and IN−. By using these
differential inputs, signals common to both inputs are rejected.
Figure 38 shows the common-mode rejection capability of the
AD4003/AD4007/AD4011 over frequency. It is important to
note that the differential input signals must be truly antiphase in
nature, 180° out of phase, which is required to keep the commonmode voltage of the input signal within the specified range
around VREF/2 as shown in Table 1.
71
70
69
68
67
66
100
1k
10k
FREQUENCY (Hz)
100k
1M
14957-303
If the analog input exceeds the reference voltage by 0.4 V, the
internal clamp circuit turns on and the current flows through
the clamp into ground, preventing the input from rising further
and potentially causing damage to the device. The clamp turns
on before D1 (see Figure 37) and can sink up to 50 mA of current.
72
CMRR (dB)
In applications where the amplifier rails are greater than VREF
and less than ground, it is possible for the output to exceed the
input voltage range of the device. In this case, the AD4003/
AD4007/AD4011 internal voltage clamp circuit ensures that the
voltage on the input pin does not exceed VREF + 0.4 V and
prevents damage to the device by clamping the input voltage in a
safe operating range and by avoiding disturbance of the reference,
which is particularly important for systems that share the
reference among multiple ADCs.
Figure 38. CMRR vs. Frequency, VDD = 1.8 V, VIO = 3.3 V, VREF = 5 V, 25°C
Switched Capacitor Input
During the acquisition phase, the impedance of the analog
inputs (IN+ or IN−) can be modeled as a parallel combination
of Capacitor CPIN and the network formed by the series connection
of RIN and CIN. CPIN is primarily the pin capacitance. RIN is typically
400 Ω and is a lumped component composed of serial resistors
and the on resistance of the switches. CIN is typically 40 pF and
is mainly the ADC sampling capacitor.
During the conversion phase, where the switches are open, the
input impedance is limited to CPIN. RIN and CIN make a singlepole, low-pass filter that reduces undesirable aliasing effects and
limits noise.
RC Filter Values
The RC filter value (represented by R and C in Figure 33 to
Figure 36) and driving amplifier can be selected depending on
the input signal bandwidth of interest at the full throughput.
Lower input signal bandwidth means that the RC cutoff can be
lower, thereby reducing noise into the converter. For optimum
performance at various throughputs, use the recommended RC
values (200 Ω, 180 pF) and the ADA4807-1.
The RC values shown in Table 10 are chosen for ease of drive considerations and greater ADC input protection. The combination
of a large R value (200 Ω) and small C value results in a reduced
dynamic load for the amplifier to drive. The smaller value of C
means less stability and phase margin concerns with the amplifier.
The large value of R limits the current into the ADC input when
the amplifier output exceeds the ADC input range.
Table 10. RC Filter and Amplifier Selection for Various Input Bandwidths
Input Signal Bandwidth (kHz)
<10
<200
>200
Multiplexed
R (Ω)
C (pF)
200
200
200
180
120
120
Recommended Amplifier
See the High-Z Mode section
ADA4807-1
ADA4897-1
ADA4897-1
Rev. B | Page 21 of 38
Recommended Fully Differential Amplifier
ADA4940-1
ADA4940-1
ADA4932-1
ADA4932-1
AD4003/AD4007/AD4011
Data Sheet
DRIVER AMPLIFIER CHOICE
102
Although the AD4003/AD4007/AD4011 are easy to drive, the
driver amplifier must meet the following requirements:
100

For ac applications, the driver must have a THD performance
commensurate with the AD4003/AD4007/AD4011.
For multichannel multiplexed applications, the driver
amplifier and the analog input circuit of the AD4003/
AD4007/AD4011 must settle for a full-scale step onto the
capacitor array at an 18-bit level (0.000384%, 3.84 ppm). In
the data sheet of the amplifier, settling at 0.1% to 0.01% is
more commonly specified. This setting may differ
significantly from the settling time at an 18-bit level and
must be verified prior to driver selection.
Single to Differential Driver
For applications using a single-ended analog signal, either
bipolar or unipolar, the ADA4940-1 single-ended to differential
driver allows a differential input to the device. The schematic is
shown in Figure 36.
High Frequency Input Signals
The AD4003/AD4007/AD4011 ac performance over a wide
input frequency range using a 5 V reference voltage is shown in
Figure 39 and Figure 40. Unlike other traditional SAR ADCs,
the AD4003/AD4007/AD4011 maintain exceptional ac performance for input frequencies up to the Nyquist frequency with
minimal performance degradation. Note that the input frequency
is limited to the Nyquist frequency of the sample rate in use.
ENOB (Bits)
SNR, SINAD (dB)
15.0
ENOB
SINAD
SNR
88
1k
14.5
10k
14.0
1M
100k
14957-211
90
INPUT FREQUENCY (Hz)
Figure 39. SNR, SINAD, and ENOB vs. Input Frequency, VDD = 1.8 V, VIO = 3.3 V,
VREF = 5 V, 25°C
–90
120
–95
115
–100
110
–105
105
–110
100
95
–115
THD
SFDR
–120
1k
10k
90
1M
100k
INPUT FREQUENCY (Hz)
Figure 40. THD and SFDR vs. Input Frequency, VDD = 1.8 V, VIO = 3.3 V,
VREF = 5 V, 25°C
Multiplexed Applications
The AD4003/AD4007/AD4011 significantly reduce system
complexity and cost for multiplexed applications that require
superior performance in terms of noise, power, and throughput.
Figure 41 shows a simplified block diagram of a multiplexed
data acquisition system including a multiplexer, an ADC driver,
and the precision SAR ADC.
MULTIPLEXER
R
ADC
DRIVER
C
SAR ADC
R
C
R
C
C
Figure 41. Multiplexed Data Acquisition Signal Chain Using the
AD4003/AD4007/AD4011
Switching multiplexer channels typically results in large voltage
steps at the ADC inputs. To ensure an accurate conversion result,
the step must be given adequate time to settle before the ADC
samples its inputs (on the rising edge of CNV). The settling
time is dependent on the drive circuitry (multiplexer and ADC
driver), RC filter values, and the time when the multiplexer
Rev. B | Page 22 of 38
14957-341
where:
f−3 dB is the input bandwidth, in megahertz, of the
AD4003/AD4007/AD4011 (10 MHz) or the cutoff
frequency of the input filter, if one is used.
N is the noise gain of the amplifier (for example, 1 in buffer
configuration).
eN is the equivalent input noise voltage of the op amp in
nV/√Hz.
15.5
94
SFDR (dB)






96
14957-214


31.5 V
 20 log 
π
2
2
 (31.5V)  2 f  3 dB ( Ne N )

16.0
92
THD (dB)
SNR LOSS

16.5
98
The noise generated by the driver amplifier must be kept
low enough to preserve the SNR and transition noise performance of the AD4003/AD4007/AD4011. The noise from
the driver is filtered by the single-pole, low-pass filter of
the AD4003/AD4007/AD4011 analog input circuit made
by RIN and CIN or by the external filter, if one is used. Because
the typical noise of the AD4003/AD4007/AD4011 is
31.5 μV rms, the SNR degradation due to the amplifier is
SENSORS

17.0
Data Sheet
AD4003/AD4007/AD4011
15
channels are switched. Switch the multiplexer channels immediately after tQUIET1 has elapsed from the start of the conversion
to maximize settling time while preventing corruption of the
conversion result. To avoid conversion corruption, do not
switch the channels during the tQUIET1 time. If the analog inputs
are multiplexed during the quiet conversion time (tQUIET1), the
current conversion may be corrupted.
12
INPUT CURRENT (μA)
9
EASE OF DRIVE FEATURES
Input Span Compression
HIGH-Z
HIGH-Z
HIGH-Z
HIGH-Z
HIGH-Z
HIGH-Z
DISABLED, 2MSPS
DISABLED, 1MSPS
DISABLED, 500kSPS
ENABLED, 2MSPS
ENABLED, 1MSPS
ENABLED, 500kSPS
6
3
0
–3
–6
–9
In single-supply applications, it is desirable to use the full range
of the ADC; however, the amplifier can have some headroom and
footroom requirements, which can be a problem, even if it is a
rail-to-rail input and output amplifier. The AD4003/AD4007/
AD4011 include a span compression feature, which increases
the headroom and footroom available to the amplifier by reducing
the input range by 10% from the top and bottom of the range
while still accessing all available ADC codes (see Figure 42). The
SNR decreases by approximately 1.9 dB (20 × log(8/10)) for the
reduced input range when span compression is enabled. Span
compression is disabled by default but can be enabled by writing to
the relevant register bit (see the Digital Interface section).
–15
–5
10% OF VREF = 0.41V
IN+/IN–
DIGITAL OUTPUT
+FSR
ALL 2N
CODES
ADC
ANALOG
INPUT
–FSR
Figure 42. Span Compression
High-Z Mode
The AD4003/AD4007/AD4011 incorporate high-Z mode, which
reduces the nonlinear charge kickback when the capacitor DAC
switches back to the input at the start of acquisition. Figure 43
shows the input current of the AD4003/AD4007/AD4011 with
high-Z mode enabled and disabled. The low input current makes
the ADC easier to drive than the traditional SAR ADCs available in
the market, even with high-Z mode disabled. The input current
reduces further to submicroampere range when high-Z mode is
enabled. The high-Z mode is disabled by default but can be enabled
by writing to the register (see Table 14). Disable high-Z mode for
input frequencies above 100 kHz or when multiplexing.
–2
–1
0
1
2
3
4
5
Figure 43. Input Current vs. Input Differential Voltage, VDD = 1.8 V
VIO = 3.3 V, VREF = 5 V, 25°C
14957-300
VREF = 4.096V
–3
INPUT DIFFERENTIAL VOLTAGE (V)
90% OF VREF = 3.69V
5V
–4
14957-343
–12
To achieve the optimum data sheet performance from high
resolution precision SAR ADCs, system designers are often
forced to use a dedicated high power, high speed amplifier to
drive the traditional switched capacitor SAR ADC inputs for
their precision applications, which is commonly encountered in
designing a precision data acquisition signal chain. The benefits
of high-Z mode are low input current for slow (<10 kHz) or dc
type signals and improved distortion (THD) performance over
a frequency range of up to 100 kHz. High-Z mode allows a
choice of lower power and lower bandwidth precision amplifiers
with a lower RC filter cutoff to drive the ADC, removing the need
for dedicated high speed ADC drivers, which saves system power,
size, and cost in precision, low bandwidth applications. High-Z
mode allows the amplifier and RC filter in front of the ADC to be
chosen based on the signal bandwidth of interest and not based
on the settling requirements of the switched capacitor SAR ADC
inputs.
Additionally, the AD4003/AD4007/AD4011 can be driven with a
much higher source impedance than traditional SARs, which
means the resistor in the RC filter can have a value 10 times larger
than previous SAR designs and, with high-Z mode enabled, can
tolerate even larger impedance. Figure 44 shows the THD performance for various source impedances with high-Z mode
disabled and enabled.
Rev. B | Page 23 of 38
AD4003/AD4007/AD4011
Data Sheet
–80
–85
–84
–90
–88
–95
–92
THD (dB)
–105
–110
–115
1kΩ HIGH-Z DISABLED
1kΩ HIGH-Z ENABLED
510Ω HIGH-Z DISABLED
510Ω HIGH-Z ENABLED
–96
–100
–104
–108
–112
–120
1
10
20
INPUT FREQUENCY (KHz)
Figure 44. THD vs. Input Frequency for Various Source Impedance, VDD = 1.8
V, VIO = 3.3 V, VREF = 5 V, 25°C
Figure 45 and Figure 46 show the AD4003/AD4007/AD4011
SNR and THD performance using the ADA4077-1 (supply
current per amplifier (ISY) = 400 μA) and ADA4610-1
(ISY = 1.5 mA per amplifier) precision amplifiers when driving the
AD4003/AD4007/AD4011 at full throughput for high-Z mode
enabled and disabled with various RC filter values. These amplifiers
achieve 96 dB to 99 dB typical SNR and better than −110 dB
THD with high-Z enabled. THD is approximately 10 dB better
with high-Z mode enabled, even for large R values. SNR maintains
close to 99 dB even with a very low RC filter bandwidth cutoff.
When high-Z mode is enabled, the ADC consumes approximately
2 mW per MSPS extra power; however, this is still significantly
lower than using dedicated ADC drivers like the ADA4807-1.
For any system, the front end usually limits the overall ac/dc
performance of the signal chain. It is evident from the data sheets
of the selected precision amplifiers, shown in Figure 45 and
Figure 46, that their own noise and distortion performance
dominates the SNR and THD specification at a certain input
frequency.
100
ADA4077-1 HIGH-Z
ADA4077-1 HIGH-Z
ADA4610-1 HIGH-Z
ADA4610-1 HIGH-Z
260kHz
1.3kΩ
470pF
DISABLED
ENABLED
DISABLED
ENABLED
1.3MHz
2.27MHz
498kHz
680Ω
390Ω
680Ω
180pF
180pF
470pF
RC FILTER BANDWIDTH (Hz)
RESISTOR (Ω), CAPACITOR (pF)
4.42MHz
200Ω
180pF
Figure 46. THD vs. RC Filter Bandwidths for Various Precision ADC Drivers,
fIN = 1 kHz (Turbo Mode On, High-Z Enabled/Disabled) VDD = 1.8 V, VIO =
3.3 V, VREF = 5 V, 25°C
Long Acquisition Phase
The AD4003/AD4007/AD4011 also feature a very fast
conversion time of 290 ns, which results in a long acquisition
phase. The acquisition is further extended by a key feature of the
AD4003/AD4007/AD4011; the ADC returns back to the
acquisition phase typically 100 ns before the end of the conversion.
This feature provides an even longer time for the ADC to acquire
the new input voltage. A longer acquisition phase reduces the
settling requirement on the driving amplifier, and a lower
power/bandwidth amplifier can be chosen. The longer acquisition
phase means that a lower RC filter (represented by R and C in
Figure 33 and Figure 36) cutoff can be used, which means a
noisier amplifier can also be tolerated. A larger value of R can
be used in the RC filter with a corresponding smaller value of C,
reducing amplifier stability concerns without affecting distortion
performance significantly. A larger value of R also results in
reduced dynamic power dissipation in the amplifier.
See Table 10 for details on setting the RC filter bandwidth and
choosing a suitable amplifier.
97
SNR (dB)
–120
14957-228
–125
–116
150Ω HIGH-Z DISABLED
150Ω HIGH-Z ENABLED
14957-229
THD (dB)
–100
94
VOLTAGE REFERENCE INPUT
91
A 10 μF (X7R, 0805 size) ceramic chip capacitor is appropriate
for the optimum performance of the reference input.
88
85
82
79
76
70
260kHz
1.3kΩ
470pF
498kHz
1.3MHz
2.27MHz
680Ω
680Ω
390Ω
470pF
180pF
180pF
RC FILTER BANDWIDTH (Hz)
RESISTOR (Ω), CAPACITOR (pF)
4.42MHz
200Ω
180pF
14957-227
ADA4077-1 HIGH-Z DISABLED
ADA4077-1 HIGH-Z ENABLED
ADA4610-1 HIGH-Z DISABLED
ADA4610-1 HIGH-Z ENABLED
73
For higher performance and lower drift, use a reference such as
the ADR4550. Use a low power reference such as the ADR3450
at the expense of a slight decrease in the noise performance. It is
recommended to use a reference buffer, such as the ADA4807-1,
between the reference and the ADC reference input. It is important
to consider the optimum capacitance necessary to keep the
reference buffer stable as well as to meet the minimum ADC
requirement stated previously in this section (that is, a 10 μF
ceramic chip capacitor, CREF).
Figure 45. SNR vs. RC Filter Bandwidths for Various Precision ADC Drivers,
fIN = 1 kHz (Turbo Mode On, High-Z Enabled/Disabled), VDD = 1.8 V, VIO =
3.3 V, VREF = 5 V, 25°C
Rev. B | Page 24 of 38
Data Sheet
AD4003/AD4007/AD4011
POWER SUPPLY
The AD4003/AD4007/AD4011 use two power supply pins: a core
supply (VDD) and a digital input/output interface supply (VIO).
VIO allows direct interface with any logic between 1.8 V and
5.5 V. To reduce the number of supplies needed, VIO and VDD
can be tied together for 1.8 V operation. The ADP7118 low noise,
CMOS, low dropout (LDO) linear regulator is recommended to
power the VDD and VIO pins. The AD4003/AD4007/AD4011
are independent of power supply sequencing between VIO and
VDD. Additionally, the AD4003/AD4007/AD4011 are insensitive
to power supply variations over a wide frequency range, as
shown in Figure 47.
80
The mode in which the device operates depends on the SDI
level when the CNV rising edge occurs. CS mode is selected if
SDI is high, and daisy-chain mode is selected if SDI is low. The
SDI hold time is such that when SDI and CNV are connected
together, daisy-chain mode is always selected.
PSRR (dB)
70
65
60
50
100
1k
10k
100k
1M
FREQUENCY (Hz)
14957-302
55
Figure 47. PSRR vs. Frequency, VDD = 1.8 V, VIO = 3.3 V, VREF = 5 V, 25°C
The AD4003/AD4007/AD4011 power down automatically at
the end of each conversion phase; therefore, the power scales
linearly with the sampling rate. This feature makes the device
ideal for low sampling rates (even a few samples per second)
and battery-powered applications. Figure 48 shows the
AD4003/AD4007/AD4011 total power dissipation and
individual power dissipation for each rail.
VDD
VIO
REF
TOTAL POWER
1k
100
10
1
0.1
0.01
10
POWER DISSIPATION MEASUREMENTS
APPLY TO EACH PRODUCT OVER ITS
SPECIFIED THROUGHPUT RANGE.
100
1k
10k
100k
1M 2M
THROUGHPUT (SPS)
14957-220
POWER DISSIPATION (µW)
10k
When in CS mode, the AD4003/AD4007/AD4011 are compatible
with SPI, QSPI™, MICROWIRE®, digital hosts, and DSPs. In this
mode, the AD4003/AD4007/AD4011 can use either a 3-wire or
4-wire interface. A 3-wire interface using the CNV, SCK, and
SDO signals minimizes wiring connections, which is useful, for
instance, in isolated applications. A 4-wire interface using the
SDI, CNV, SCK, and SDO signals allows CNV, which initiates the
conversions, to be independent of the readback timing (SDI).
This interface is useful in low jitter sampling or simultaneous
sampling applications.
The AD4003/AD4007/AD4011 provide a daisy-chain feature
using the SDI input for cascading multiple ADCs on a single
data line, similar to a shift register.
75
100k
modes. The AD4003/AD4007/AD4011 can also be programmed
via 16-bit SPI writes to the configuration registers.
Figure 48. Power Dissipation vs. Throughput, VDD = 1.8 V, VIO = 3.3 V,
VREF = 5 V, 25°C
DIGITAL INTERFACE
Although the AD4003/AD4007/AD4011 have a reduced
number of pins, they offer flexibility in their serial interface
In either 3-wire or 4-wire mode, the AD4003/AD4007/AD4011
offer the option of forcing a start bit in front of the data bits. This
start bit can be used as a busy signal indicator to interrupt the
digital host and trigger the data reading. Otherwise, without a
busy indicator, the user must time out the maximum conversion
time prior to readback.
The busy indicator feature is enabled in CS mode if CNV or SDI
is low when the ADC conversion ends.
The state of the SDO on power-up is either low or high-Z
depending on the states of CNV and SDI, as shown in Table 11.
Table 11. State of SDO on Power-Up
CNV
0
0
1
1
SDI
0
1
0
1
SDO
Low
Low
Low
High-Z
The AD4003/AD4007/AD4011 have turbo mode capability in
both 3-wire and 4-wire mode. Turbo mode is enabled by writing
to the configuration register and replaces the busy indicator feature
when enabled. Turbo mode allows a slower SPI clock rate, making
interfacing simpler. The maximum throughput of 2 MSPS for
the AD4003 can be achieved only with turbo mode enabled and
a minimum SCK rate of 75 MHz. The SCK rate must be
sufficiently fast to ensure the conversion result is clocked out
before another conversion is initiated. The minimum required
SCK rate for an application can be derived based on the sample
period (tCYC), the number of bits that must be read (including
data and optional status bits), and the digital interface mode
being used. Timing diagrams and explanations for each digital
interface mode are given in the digital modes of operation sections
Rev. B | Page 25 of 38
AD4003/AD4007/AD4011
Data Sheet
by seven command bits. This command determines whether
that operation is a write or a read. The AD4003/AD4007/
AD4011 command register is shown in Table 13.
below (see the CS Mode, 3-Wire Turbo Mode section through
the CS Mode, 4-Wire with Busy Indicator section).
Status bits can also be clocked out at the end of the conversion
data if the status bits are enabled in the configuration register.
There are six status bits in total as described in Table 12.
Table 13. Command Register
The AD4003/AD4007/AD4011 are configured by 16-bit SPI
writes to the desired configuration register. The 16-bit word can
be written via the SDI line while CNV is held low. The 16-bit word
consists of an 8-bit header and 8-bit register data. For isolated
systems, the ADuM141D is recommended, which can support the
75 MHz SCK rate requires to run the AD4003 at its full
throughput of 2 MSPS.
REGISTER READ/WRITE FUNCTIONALITY
The AD4003/AD4007/AD4011 register bits are programmable,
and their default statuses are shown in Table 12. The register
map is shown in Table 14. The OV clamp flag is a read only
sticky bit, and it is cleared only if the register is read and the
overvoltage condition is no longer present. The OV clamp flag
gives an indication of overvoltage condition when it is set to 0.
Bit 6
R/W
Bit 5
0
Bit 4
1
Bit 3
0
Bit 2
1
Bit 1
0
Bit 0
0
All register read/writes must occur while CNV is low. Data on
SDI is clocked in on the rising edge of SCK. Data on SDO is
clocked out on the falling edge of SCK. At the end of the data
transfer, SDO is put in a high impedance state on the rising edge of
CNV if daisy-chain mode is not enabled. If daisy-chain mode is
enabled, SDO goes low on the rising edge of CNV. Register reads
are not allowed in daisy-chain mode.
A register write requires three signal lines: SCK, CNV, and SDI.
During a register write, to read the current conversion results
on SDO, the CNV pin must be brought low after the conversion
is completed; otherwise, the conversion results may be incorrect
on SDO. However, the register write occurs regardless.
The LSB of each configuration register is reserved because a user
reading 16-bit conversion data may be limited to a 16-bit SPI
frame. The state of SDI on the last bit in the SDI frame may be
the state that then persists when CNV rises. Because interface
mode is partly set based on the SDI state when CNV rises, in
this scenario, the user may need to set the final SDI state.
Table 12. Register Bits
Register Bits
OV Clamp Flag
Span Compression
High-Z Mode
Turbo Mode
Enable Six Status Bits
Bit 7
WEN
Default Status
1 bit, 1 = inactive (default)
1 bit, 0 = disabled (default)
1 bit, 0 = disabled (default)
1 bit, 0 = disabled (default)
1 bit, 0 = disabled (default)
All access to the register map must start with a write to the 8-bit
command register in the SPI interface block. The AD4003/
AD4007/AD4011 ignore all 1s until the first 0 is clocked in
(represented by WEN in Figure 49, Figure 50, and Table 13); the
value loaded into the command register is always a 0 followed
The timing diagrams in Figure 49 through Figure 51 show how
data is read and written when the AD4003/AD4007/AD4011
are configured in register read, write, and daisy-chain mode.
Table 14. Register Map
ADDR[1:0]
0x0
Bit 7
Reserved
Bit 6
Reserved
Bit 5
Reserved
Bit 4
Enable six
status bits
Bit 3
Span
compression
Rev. B | Page 26 of 38
Bit 2
High-Z
mode
Bit 1
Turbo
mode
Bit 0
OV clamp flag (read only
sticky bit)
Reset
0xE1
Data Sheet
AD4003/AD4007/AD4011
tCYC
tCNVH
tSCK
CNV
tSCNVSCK
SCK
1
tSCKL
2
3
4
5
6
8
7
9
10
11
tHSDISCK
tSSDISCK
SDI
1
WEN
0
1
0
1
ADDR[1:0]
1
0
1
0
1
0
0
D16
15
16
D15
D13
D14
D12
D11
B6
B7
D10
tDIS
B5
B3
B4
B2
B1
X1
B0
14957-021
D17
14
tHSDO
tDSDO
tEN
SDO
13
tSCKH
R/W
0
12
1X INDICATES A DON’T CARE BIT.
Figure 49. Register Read Timing Diagram
tCYC
tCNVH
tSCK
1
tHCNVSCK
CNV
tSCNVSCK
SCK
1
tSCKL
2
3
4
9
5
10
11
tHSDISCK
12
13
14
15
16
17
18
tSCKH
tSSDISCK
1
SDI
WEN
R/W
0
1
0
1
0
0
1
0
1
0
ADDR[1:0]
0
B7
B6
0
D17
D16
D15
D14
D13
D12
D11
B4
B3
B2
B1
1
B0
tHSDO
tDSDO
EN
SDO
B5
D10
D8
D9
D7
D6
D5
D4
D3
D2
D1
D0
14957-022
CONVERSION RESULT ON D17:0
1THE USER MUST WAIT t
CONV TIME WHEN READING BACK THE CONVERSION RESULT AND DOING A REGISTER WRITE AT THE SAME TIME.
Figure 50. Register Write Timing Diagram
tCYC
tCNVH
tSCK
CNV
tSCNVSCK
SCK
tSCKL
1
24
tSCKH
SDIA
SDOA /SDIB
0
COMMAND (0x14)
0
DATA (0xAB)
COMMAND (0x14)
0
DATA (0xAB)
0
0
COMMAND (0x14)
Figure 51. Register Write Timing Diagram, Daisy-Chain Mode
Rev. B | Page 27 of 38
0
14957-023
tDIS
SDOB
AD4003/AD4007/AD4011
Data Sheet
The SDO line returns to high impedance after the sixth status
bit is clocked out (except in daisy-chain mode). The user is not
required to clock out all status bits to start the next conversion.
The serial interface timing for CS mode, 3-wire without busy
indicator, including status bits, is shown in Figure 52.
STATUS WORD
The 6-bit status word can be appended to the end of a conversion
result, and the default conditions of these bits are shown in Table
15. The status bits must be enabled in the register setting. When
the OV clamp flag is a 0, it indicates an overvoltage condition. The
OV clamp flag status bit updates on a per conversion basis.
Table 15. Status Bits (Default Conditions)
Bit 5
OV clamp flag
Bit 4
Span compression
Bit 3
High-Z mode
Bit 2
Turbo mode
Bit 1
Reserved
Bit 0
Reserved
SDI = 1
tCYC
tCNVH
CN V
tACQ
CONVERSION
ACQUISITION
tSCK
tCONV
tQUIET2
tSCKL
SCK
1
2
3
16
23
24
tSCKH
tHSDO
tEN
SDO
22
18
17
tDSDO
D17
D16
D15
tDIS
D1
D0
b1
STATUS BITS B[5:0]
Figure 52. CS Mode, 3-Wire Without Busy Indicator Serial Interface Timing Diagram Including Status Bits (SDI High)
Rev. B | Page 28 of 38
b0
14957-024
ACQUISITION
Data Sheet
AD4003/AD4007/AD4011
When SDI is forced high, a rising edge on CNV initiates a
conversion. The previous conversion data is available to read
after the CNV rising edge. The user must wait tQUIET1 time after
CNV is brought high before bringing CNV low to clock out the
previous conversion result. The user must also wait tQUIET2 time
after the last falling edge of SCK to when CNV is brought high.
CS MODE, 3-WIRE TURBO MODE
This mode is typically used when a single AD4003/AD4007/
AD4011 device is connected to an SPI-compatible digital host. It
provides additional time during the end of the ADC conversion
process to clock out the previous conversion result, providing a
lower SCK rate. The AD4003 can achieve a throughput rate of
2 MSPS only when turbo mode is enabled and using a minimum
SCK rate of 75 MHz. With turbo mode enabled, the AD4007 can
also achieve its maximum throughput rate of 1 MSPS with a
minimum SCK rate of 25 MHz, and the AD4011 can achieve its
maximum throughput rate of 500 kSPS with a minimum SCK
rate of 11 MHz. The connection diagram is shown in Figure 53,
and the corresponding timing diagram is shown in Figure 54.
When the conversion is complete, the AD4003/AD4007/AD4011
enter the acquisition phase and power down. When CNV goes
low, the MSB is output to SDO. The remaining data bits are
clocked by subsequent SCK falling edges. The data is valid on
both SCK edges. Although the rising edge can capture the data,
a digital host using the SCK falling edge allows a faster reading
rate, provided it has an acceptable hold time. After the 18th SCK
falling edge or when CNV goes high (whichever occurs first),
SDO returns to high impedance.
This mode replaces the 3-wire with busy indicator mode by
programming the turbo mode bit, Bit 1 (see Table 14).
CONVERT
DIGITAL HOST
CNV
VIO
SDI
AD4003/
AD4007/
AD4011
SDO
DATA IN
14957-425
SCK
CLK
Figure 53. CS Mode, 3-Wire Turbo Mode Connection Diagram (SDI High)
SDI = 1
tCYC
CNV
tACQ
CONVERSION
ACQUISITION
ACQUISITION
tSCK
CONV
tSCKL
QUIET2
tQUIET1
2
3
16
17
tSCKH
tHSDO
tEN
SDO
18
tDSDO
D17
D16
D15
tDIS
D1
D0
Figure 54. CS Mode, 3-Wire Turbo Mode Serial Interface Timing Diagram (SDI High)
Rev. B | Page 29 of 38
14957-029
1
SCK
AD4003/AD4007/AD4011
Data Sheet
When the conversion is complete, the AD4003/AD4007/
AD4011 enter the acquisition phase and power down. When
CNV goes low, the MSB is output onto SDO. The remaining data
bits are clocked by subsequent SCK falling edges. The data is valid
on both SCK edges. Although the rising edge can capture the data,
a digital host using the SCK falling edge allows a faster reading
rate, provided it has an acceptable hold time. After the 18th SCK
falling edge or when CNV goes high (whichever occurs first),
SDO returns to high impedance.
CS MODE, 3-WIRE WITHOUT BUSY INDICATOR
This mode is typically used when a single AD4003/AD4007/
AD4011 device is connected to an SPI-compatible digital host.
The connection diagram is shown in Figure 55, and the
corresponding timing diagram is shown in Figure 56.
With SDI tied to VIO, a rising edge on CNV initiates a conversion,
selects the CS mode, and forces SDO to high impedance. After a
conversion is initiated, it continues until completion irrespective of
the state of CNV. This feature can be useful, for instance, to bring
CNV low to select other SPI devices, such as analog multiplexers;
however, CNV must be returned high before the minimum
conversion time elapses and then held high for the maximum
possible conversion time to avoid the generation of the busy
signal indicator.
There must not be any digital activity on SCK during the
conversion.
CONVERT
DIGITAL HOST
CNV
VIO
SDI
AD4003/AD4007/
AD4011
SDO
DATA IN
14957-025
SCK
CLK
Figure 55. CS Mode, 3-Wire Without Busy Indicator Connection Diagram (SDI High)
SDI = 1
tCYC
tCNVH
CNV
tACQ
ACQUISITION
CONVERSION
tSCK
tCONV
tSCKL
SCK
1
2
3
16
tHSDO
17
18
tSCKH
tEN
SDO
tQUIET2
tDSDO
D17
D16
D15
tDIS
D1
Figure 56. CS Mode, 3-Wire Without Busy Indicator Serial Interface Timing Diagram (SDI High)
Rev. B | Page 30 of 38
D0
14957-026
ACQUISITION
Data Sheet
AD4003/AD4007/AD4011
When the conversion is complete, SDO goes from high
impedance to low impedance. With a pull-up resistor of 1 kΩ
on the SDO line, this transition can be used as an interrupt
signal to initiate the data reading controlled by the digital host.
The AD4003/AD4007/AD4011 then enter the acquisition phase
and power down. The data bits are then clocked out, MSB first,
by subsequent SCK falling edges. The data is valid on both SCK
edges. Although the rising edge can capture the data, a digital
host using the SCK falling edge allows a faster reading rate,
provided it has an acceptable hold time. After the optional 19th
SCK falling edge or when CNV goes high (whichever occurs
first), SDO returns to high impedance.
CS MODE, 3-WIRE WITH BUSY INDICATOR
This mode is typically used when a single AD4003/AD4007/
AD4011 device is connected to an SPI-compatible digital host
with an interrupt input (IRQ).
The connection diagram is shown in Figure 57, and the
corresponding timing diagram is shown in Figure 58.
With SDI tied to VIO, a rising edge on CNV initiates a conversion,
selects the CS mode, and forces SDO to high impedance. SDO
is maintained in high impedance until the completion of the
conversion irrespective of the state of CNV. Prior to the minimum
conversion time, CNV can select other SPI devices, such as analog
multiplexers; however, CNV must be returned low before the
minimum conversion time elapses and then held low for the
maximum possible conversion time to guarantee the generation
of the busy signal indicator.
If multiple AD4003/AD4007/AD4011 devices are selected at the
same time, the SDO output pin handles this contention without
damage or induced latch-up. Meanwhile, it is recommended to
keep this contention as short as possible to limit extra power
dissipation.
There must not be any digital activity on the SCK during the
conversion.
CONVERT
VIO
DIGITAL HOST
CNV
VIO
1kΩ
AD4003/AD4007/
AD4011
SDO
DATA IN
IRQ
SCK
14957-027
SDI
CLK
Figure 57. CS Mode, 3-Wire with Busy Indicator Connection Diagram (SDI High)
SDI = 1
tCYC
tCNVH
CNV
tACQ
CONVERSION
ACQUISITION
tSCK
tCONV
tSCKL
SCK
1
2
3
tQUIET2
17
tHSDO
18
19
tSCKH
tDSDO
SDO
D17
D16
tDIS
D1
Figure 58. CS Mode, 3-Wire with Busy Indicator Serial Interface Timing Diagram (SDI High)
Rev. B | Page 31 of 38
D0
14957-028
ACQUISITION
AD4003/AD4007/AD4011
Data Sheet
With SDI high, a rising edge on CNV initiates a conversion.
The previous conversion data is available to read after the CNV
rising edge. The user must wait tQUIET1 time after CNV is brought
high before bringing SDI low to clock out the previous conversion
result. The user must also wait tQUIET2 time after the last falling
edge of SCK to when CNV is brought high.
CS MODE, 4-WIRE TURBO MODE
This mode is typically used when a single AD4003/AD4007/
AD4011 is connected to an SPI-compatible digital host. It provides
additional time during the end of the ADC conversion process
to clock out the previous conversion result, giving a lower SCK
rate. The AD4003 can achieve a throughput rate of 2 MSPS only
when turbo mode is enabled and using a minimum SCK rate of
75 MHz. With turbo mode enabled, the AD4007 can also achieve
its maximum throughput rate of 1 MSPS with a minimum SCK
rate of 25 MHz, and the AD4011 can achieve its maximum
throughput rate of 500 kSPS with a minimum SCK rate of 11 MHz.
The connection diagram is shown in Figure 59, and the corresponding timing diagram is shown in Figure 60.
When the conversion is complete, the AD4003/AD4007/AD4011
enter the acquisition phase and power down. The ADC result
can be read by bringing its SDI input low, which consequently
outputs the MSB onto SDO. The remaining data bits are then
clocked by subsequent SCK falling edges. The data is valid on
both SCK edges. Although the rising edge can capture the data,
a digital host using the SCK falling edge allows a faster reading
rate, provided it has an acceptable hold time. After the 18th SCK
falling edge or when SDI goes high (whichever occurs first), SDO
returns to high impedance.
This mode replaces the 4-wire with busy indicator mode by
programming the turbo mode bit, Bit 1 (see Table 14).
CS1
CONVERT
VIO
DIGITAL HOST
CNV
AD4003/
AD4007/
AD4011
SDO
DATA IN
IRQ
SCK
14957-432
SDI
1kΩ
CLK
Figure 59. CS Mode, 4-Wire Turbo Mode Connection Diagram
CNV
tCYC
tSSDICNV
SDI
tHSDICNV
ACQUISITION
tACQ
CONVERSION
ACQUISITION
tSCK
tCONV
tSCKL
tQUIET2
tQUIET1
1
2
3
16
tHSDO
18
tSCKH
tEN
SDO
17
tDIS
tDSDO
D17
D16
D15
Figure 60. CS Mode, 4-Wire Turbo Mode Timing Diagram
Rev. B | Page 32 of 38
D1
D0
14957-034
SCK
Data Sheet
AD4003/AD4007/AD4011
When the conversion is complete, the AD4003/AD4007/
AD4011 enter the acquisition phase and power down. Each
ADC result can be read by bringing its SDI input low, which
consequently outputs the MSB onto SDO. The remaining data
bits are then clocked by subsequent SCK falling edges. The data
is valid on both SCK edges. Although the rising edge can
capture the data, a digital host using the SCK falling edge allows
a faster reading rate, provided it has an acceptable hold time.
After the 18th SCK falling edge or when SDI goes high (whichever
occurs first), SDO returns to high impedance and another
AD4003/AD4007/AD4011 can be read.
CS MODE, 4-WIRE WITHOUT BUSY INDICATOR
This mode is typically used when multiple AD4003/AD4007/
AD4011 devices are connected to an SPI-compatible digital host.
A connection diagram example using two AD4003/AD4007/
AD4011 devices is shown in Figure 61, and the corresponding
timing diagram is shown in Figure 62.
With SDI high, a rising edge on CNV initiates a conversion,
selects the CS mode, and forces SDO to high impedance. In this
mode, CNV must be held high during the conversion phase and
the subsequent data readback. If SDI and CNV are low, SDO is
driven low. Prior to the minimum conversion time, SDI can select
other SPI devices, such as analog multiplexers; however, SDI
must be returned high before the minimum conversion time
elapses and then held high for the maximum possible conversion
time to avoid the generation of the busy signal indicator.
CS2
CS1
CONVERT
CNV
CNV
SDI
AD4003/AD4007/
AD4011
SDO
SDI
AD4003/AD4007/
AD4011
DEVICE A
DEVICE B
SCK
SCK
DIGITAL HOST
SDO
14957-030
DATA IN
CLK
Figure 61. CS Mode, 4-Wire Without Busy Indicator Connection Diagram
CYC
CNV
tACQ
ACQUISITION
CONVERSION
ACQUISITION
tCONV
tQUIET2
tSSDICNV
SDI (CS1)
tHSDICNV
SDI (CS2)
tSCK
tSCKL
1
2
3
16
tHSDO
18
19
20
34
35
36
tSCKH
tDSDO
tEN
SDO
17
D17
D16
D15
tDIS
D1
D0
D17
D16
Figure 62. CS Mode, 4-Wire Without Busy Indicator Serial Interface Timing Diagram
Rev. B | Page 33 of 38
D1
D0
14957-031
SCK
AD4003/AD4007/AD4011
Data Sheet
SDI must be returned low before the minimum conversion time
elapses and then held low for the maximum possible conversion
time to guarantee the generation of the busy signal indicator.
CS MODE, 4-WIRE WITH BUSY INDICATOR
This mode is typically used when a single AD4003/AD4007/
AD4011 device is connected to an SPI-compatible digital host
with an interrupt input (IRQ), and when it is desired to keep
CNV, which samples the analog input, independent of the signal
used to select the data reading. This independence is particularly
important in applications where low jitter on CNV is desired.
When the conversion is complete, SDO goes from high impedance
to low impedance. With a pull-up resistor of 1 kΩ on the SDO
line, this transition can be used as an interrupt signal to initiate
the data readback controlled by the digital host. The AD4003/
AD4007/AD4011 then enter the acquisition phase and power
down. The data bits are then clocked out, MSB first, by subsequent
SCK falling edges. The data is valid on both SCK edges.
Although the rising edge can capture the data, a digital host
using the SCK falling edge allows a faster reading rate, provided
it has an acceptable hold time. After the optional 19th SCK
falling edge or when SDI goes high (whichever occurs first),
SDO returns to high impedance.
The connection diagram is shown in Figure 63, and the
corresponding timing diagram is shown in Figure 64.
With SDI high, a rising edge on CNV initiates a conversion,
selects the CS mode, and forces SDO to high impedance. In this
mode, CNV must be held high during the conversion phase and
the subsequent data readback. If SDI and CNV are low, SDO is
driven low. Prior to the minimum conversion time, SDI can
select other SPI devices, such as analog multiplexers; however,
CS1
CONVERT
VIO
DIGITAL HOST
CNV
1kΩ
AD4003/AD4007/
AD4011
SDO
DATA IN
IRQ
SCK
14957-032
SDI
CLK
Figure 63. CS Mode, 4-Wire with Busy Indicator Connection Diagram
tCYC
CNV
tACQ
ACQUISITION
CONVERSION
ACQUISITION
tCONV
tQUIET2
tSSDICNV
SDI
tSCK
tHSDICNV
tSCKL
SCK
1
2
3
17
18
19
tSCKH
tHSDO
tDSDO
tDIS
SDO
D17
D16
D1
Figure 64. CS Mode, 4-Wire with Busy Indicator Serial Interface Timing Diagram
Rev. B | Page 34 of 38
D0
14957-033
tEN
Data Sheet
AD4003/AD4007/AD4011
rising edges. Each ADC in the daisy-chain outputs its data MSB
first, and 18 × N clocks are required to read back the N ADCs.
The data is valid on both SCK edges. The maximum conversion
rate is reduced because of the total readback time.
DAISY-CHAIN MODE
Use this mode to daisy-chain multiple AD4003/AD4007/AD4011
devices on a 3-wire or 4-wire serial interface. This feature is useful
for reducing component count and wiring connections, for
example, in isolated multiconverter applications or for systems
with a limited interfacing capacity. Data readback is analogous
to clocking a shift register.
It is possible to write to each ADC register in daisy-chain mode.
The timing diagram is shown in Figure 51. This mode requires
4-wire operation because data is clocked in on the SDI line with
CNV held low. The same command byte and register data can
be shifted through the entire chain to program all ADCs in the
chain with the same register contents, which requires 8 × (N + 1)
clocks for N ADCs. It is possible to write different register contents
to each ADC in the chain by writing to the furthest ADC in the
chain, first using 8 × (N + 1) clocks, and then the second furthest
ADC with 8 × N clocks, and so forth until reaching the nearest
ADC in the chain, which requires 16 clocks for the command
and register data. It is not possible to read register contents in
daisy-chain mode; however, the six status bits can be enabled if
the user wants to determine the ADC configuration. Note that
enabling the status bits requires six extra clocks to clock out the
ADC result and the status bits per ADC in the chain. Turbo
mode cannot be used in daisy-chain mode.
A connection diagram example using two AD4003/AD4007/
AD4011 devices is shown in Figure 65, and the corresponding
timing diagram is shown in Figure 66.
When SDI and CNV are low, SDO is driven low. With SCK low,
a rising edge on CNV initiates a conversion, selects daisy-chain
mode, and disables the busy indicator. In this mode, CNV is
held high during the conversion phase and the subsequent data
readback. When the conversion is complete, the MSB is output
onto SDO and the AD4003/AD4007/AD4011 enter the
acquisition phase and power down. The remaining data bits
stored in the internal shift register are clocked out of SDO by
subsequent SCK falling edges. For each ADC, SDI feeds the
input of the internal shift register and is clocked by the SCK
CONVERT
SDI
CNV
AD4003/AD4007/
AD4011
SDO
SDI
DIGITAL HOST
AD4003/AD4007/
AD4011
DEVICE A
DEVICE B
SCK
SCK
SDO
DATA IN
14957-036
CNV
CLK
Figure 65. Daisy-Chain Mode Connection Diagram
SDIA = 0
tCYC
CNV
tACQ
CONVERSION
ACQUISITION
tCONV
tSCK
tSCKL
tQUIET2
SCK
1
2
3
16
17
tSSDISCK
tHSCKCNV
tQUIET2
18
19
20
34
35
36
tSCKH
tHSDISCK
tEN
D A17
SDOA = SDIB
DA16
DA15
DA1
DA0
tHSDO
tDIS
tDSDO
SDOB
D B17
DB16
DB15
DB1
DB0
DA17
Figure 66. Daisy-Chain Mode Serial Interface Timing Diagram
Rev. B | Page 35 of 38
DA16
DA1
DA0
14957-037
ACQUISITION
AD4003/AD4007/AD4011
Data Sheet
LAYOUT GUIDELINES
The PCB that houses the AD4003/AD4007/AD4011 must be
designed so that the analog and digital sections are separated and
confined to certain areas of the board. The pinout of the AD4003/
AD4007/AD4011, with its analog signals on the left side and its
digital signals on the right side, eases this task.
At least one ground plane must be used. It can be common or
split between the digital and analog sections. In the latter case,
join the planes underneath the AD4003/AD4007/AD4011
devices.
14957-038
Avoid running digital lines under the device because they couple
noise onto the die, unless a ground plane under the AD4003/
AD4007/AD4011 is used as a shield. Fast switching signals,
such as CNV or clocks, must not run near analog signal paths.
Avoid crossover of digital and analog signals.
Figure 67. Example Layout of the AD4003 (Top Layer)
The AD4003/AD4007/AD4011 voltage reference input (REF)
has a dynamic input impedance. Decouple the REF pin with
minimal parasitic inductances by placing the reference decoupling
ceramic capacitor close to (ideally right up against) the REF and
GND pins and connect them with wide, low impedance traces.
An example of the AD4003 layout following these rules is shown in
Figure 67 and Figure 68. Note that the AD4007/AD4011 layout
is equivalent to the AD4003 layout.
EVALUATING THE AD4003/AD4007/AD4011
PERFORMANCE
Other recommended layouts for the AD4003/AD4007/AD4011
are outlined in the user guide of the evaluation board for the
AD4003 (EVAL-AD4003FMCZ). The evaluation board package
includes a fully assembled and tested evaluation board with the
AD4003 documentation, and software for controlling the board
from a PC via the EVAL-SDP-CH1Z. The EVAL-AD4003FMCZ
can also be used to evaluate the AD4007/AD4011 by limiting
the throughput to 1 MSPS/500 kSPS in its software (see UG-1042).
Rev. B | Page 36 of 38
14957-039
Finally, decouple the VDD and VIO power supplies of the
AD4003/AD4007/AD4011 with ceramic capacitors, typically
0.1 μF placed close to the AD4003/AD4007/AD4011 and
connected using short, wide traces to provide low impedance
paths and to reduce the effect of glitches on the power supply lines.
Figure 68. Example Layout of the AD4003 (Bottom Layer)
Data Sheet
AD4003/AD4007/AD4011
OUTLINE DIMENSIONS
3.10
3.00
2.90
10
3.10
3.00
2.90
1
5.15
4.90
4.65
6
5
PIN 1
IDENTIFIER
0.50 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.30
0.15
0.70
0.55
0.40
0.23
0.13
6°
0°
091709-A
0.15
0.05
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-BA
Figure 69. 10-Lead Mini Small Outline Package [MSOP]
(RM-10)
Dimensions shown in millimeters
DETAIL A
(JEDEC 95)
2.48
2.38
2.23
3.10
3.00 SQ
2.90
0.50 BSC
10
6
1.74
1.64
1.49
EXPOSED
PAD
0.50
0.40
0.30
1
5
BOTTOM VIE W
TOP VIEW
PKG-004362
0.80
0.75
0.70
SEATING
PLANE
SIDE VIEW
0.30
0.25
0.20
0.05 MAX
0.02 NOM
COPLANARITY
0.08
PIN 1
INDIC ATOR AREA OPTIONS
(SEE DETAIL A)
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
0.20 REF
Figure 70. 10-Lead Lead Frame Chip Scale Package [LFCSP]
3 mm × 3 mm Body and 0.75 mm Package Height
(CP-10-9)
Dimensions shown in millimeters
Rev. B | Page 37 of 38
0.20 MIN
02-07-2017-C
PIN 1 INDEX
AREA
AD4003/AD4007/AD4011
Data Sheet
ORDERING GUIDE
Model1,2
AD4003BRMZ
AD4003BRMZ-RL7
AD4003BCPZ-RL7
AD4007BRMZ
AD4007BRMZ-RL7
AD4007BCPZ-RL7
AD4011BCPZ-RL7
EVAL-AD4003FMCZ
1
2
Integral
Nonlinearity (INL)
±1.0 LSB
±1.0 LSB
±1.0 LSB
±1.0 LSB
±1.0 LSB
±1.0 LSB
±1.0 LSB
Temperature
Range
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
Ordering
Quantity
Tube, 50
Reel, 1000
Reel, 1500
Tube, 50
Reel, 1000
Reel, 1500
Reel, 1500
Package Description
10-Lead MSOP
10-Lead MSOP
10-Lead LFCSP
10-Lead MSOP
10-Lead MSOP
10-Lead LFCSP
10-Lead LFCSP
AD4003 Evaluation Board
Compatible with EVAL-SDP-CH1Z
Package
Option
RM-10
RM-10
CP-10-9
RM-10
RM-10
CP-10-9
CP-10-9
Branding
C8C
C8C
C8C
C8R
C8R
C8R
C8V
Z = RoHS Compliant Part.
The EVAL-AD4003FMCZ can also be used to evaluate the AD4007 and AD4011 by setting the throughput to 1 MSPS and 500 kSPS in its software, respectively (see
UG-1042).
©2016–2017 Analog Devices, Inc. All rights reserved. Trademarks
and registered trademarks are the property of their respective
owners.
D14957-0-10/17(B)
Rev. B | Page 38 of 38
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