AD AD5410AREZ

Preliminary Technical Data
Single Channel, 16-Bit, Serial Input,
Current Source DAC
AD5410/AD5420
FEATURES
GENERAL DESCRIPTION
12/16-Bit Resolution and Monotonicity
Current Output Ranges: 4–20mA, 0–20mA or 0–24mA
0.1% typ Total Unadjusted Error (TUE)
5ppm/°C Output Drift
Flexible Serial Digital Interface
On-Chip Output Fault Detection
On-Chip Reference (10 ppm/°C Max)
Asynchronous CLEAR Function
Power Supply (AVDD) Range
10.8V to 60 V; AD5410/AD5420ACPZ
10.8V to 40V; AD5410/AD5420AREZ
Output Loop Compliance to AVDD – 2.5 V
Temperature Range: -40°C to +85°C
TSSOP and LFCSP Packages
The AD5410/AD5420 is a low-cost, precision, fully integrated
12/16-bit converter offering a programmable current source
output designed to meet the requirements of industrial process
control applications.The output current range is programmable
to 4mA to 20 mA, 0mA to 20mA or an over range function of
0mA to 24mA. The output is open circuit protected and can
drive inductive loads of 1H. The device is specified to operate
with a power supply range from 10.8 V to 40V
AD5410/AD5420AREZ) or 10.8V to 60V
(AD5410/AD5420ACPZ). Output loop compliance is 0 V to
AVDD – 2.5 V.
The flexible serial interface is SPI and MICROWIRE
compatible and can be operated in 3-wire mode to minimize the
digital isolation required in isolated applications.
The device also includes a power-on-reset function ensuring
that the device powers up in a known state and an
asynchronous CLEAR pin which sets the output to the low end
of the selected current range.
The total output error is typically ±0.1% FSR.
APPLICATIONS
Process Control
Actuator Control
PLC
Table 1. Related Devices
Part Number
AD5422
AD5412
AD5410
Description
Single Channel, 16-Bit, Serial
Input Current Source and
Voltage Output DAC
Single Channel, 12-Bit, Serial
Input Current Source and
Voltage Output DAC
Single Channel, 12-Bit, Serial
Input Current Source DAC
Rev. PrE
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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2008 Analog Devices, Inc. All rights reserved.
AD5410/AD5420
Preliminary Technical Data
TABLE OF CONTENTS
Features .............................................................................................. 1
RESET register ............................................................................ 22
Applications....................................................................................... 1
Status register .............................................................................. 22
General Description ......................................................................... 1
Features ............................................................................................ 23
Revision History ............................................................................... 2
fault alert...................................................................................... 23
Functional Block Diagram .............................................................. 3
Asynchronous Clear (CLEAR) ................................................. 23
Specifications..................................................................................... 4
Internal Reference ...................................................................... 23
AC Performance Characteristics ................................................ 6
External current setting resistor............................................... 23
Timing Characteristics ................................................................ 7
Digital Power Supply.................................................................. 23
Absolute Maximum Ratings............................................................ 9
External boost function............................................................. 23
ESD Caution.................................................................................. 9
digital Slew rate control ............................................................. 24
Pin Configuration and Function Descriptions........................... 10
IOUT Filtering Capacitors (LFCSP PAckage) ............................ 25
Typical Performance Characteristics ........................................... 11
Applications Information .............................................................. 26
Terminology .................................................................................... 16
driving inductive loads .............................................................. 26
Theory of Operation ...................................................................... 17
Transient voltage protection ..................................................... 26
Architecture................................................................................. 17
Layout Guidelines....................................................................... 26
Serial Interface ............................................................................ 17
Galvanically Isolated Interface ................................................. 26
power-up state............................................................................. 21
Microprocessor Interfacing....................................................... 26
Transfer Function ....................................................................... 21
Thermal and supply considerations......................................... 27
Data Register ............................................................................... 21
Outline Dimensions ....................................................................... 28
Control Register.......................................................................... 21
Ordering Guide .......................................................................... 28
REVISION HISTORY
PrE – Preliminary Version. May 2, 2008
Rev. PrE | Page 2 of 30
Preliminary Technical Data
AD5410/AD5420
FUNCTIONAL BLOCK DIAGRAM
DVCC
SELECT
CLEA R
SELECT
DVCC
CAP1* CAP2*
AV DD
AD5410/AD5420
R2
BOOST
CLEA R
LATCH
SCLK
SDIN
SDO
R3
INPUT SHIFT
REGISTER
AND
CONTROL
LOGIC
16
/
12/16-Bit
DAC
IOUT
FAULT
R1
POWER
ON
RESET
DGND*
VREF
REFOUT
AGND
REFIN
*LFCSP Package
Figure 1.
Rev. PrE | Page 3 of 30
R SET
AD5410/AD5420
Preliminary Technical Data
SPECIFICATIONS
AVDD = 10.8V to 40V/60V1, AGND = DGND = 0 V, REFIN= +5 V external; DVCC = 2.7 V to 5.5 V, RL = 300Ω, HL = 50mH;
all specifications TMIN to TMAX, 0 to 24 mA range unless otherwise noted.
Table 2.
Value2
0 to 24
0 to 20
4 to 20
Unit
mA
mA
mA
Test Conditions/Comments
Bits
Bits
% FSR max
ppm/°C typ
% FSR max
% FSR max
LSB max
% FSR max
ppm FSR/°C typ
% FSR max
AD5410
AD5420
Over temperature, supplies, and time, typically 0.1% FSR
Differential Nonlinearity (DNL)
Offset Error
Offset Error Drift
Gain Error
12
16
±0.3
±5
±0.024
±0.012
±1
±0.05
±5
±0.05
Gain TC3
Full-Scale Error
±8
0.05
ppm FSR/°C max
% FSR max
±8
ppm FSR/°C
AVDD - 2.5
TBD
TBD
1200
1
1
50
V max
ppm FSR/500 hr typ
ppm FSR/1000 hr typ
Ω max
H max
µA/V max
MΩ typ
5
30
4 to 5
V nom
kΩ min
V min to V max
±1% for specified performance
Typically 40 kΩ
4.998 to 5.002
±10
18
120
±40
±50
TBD
5
7
10
TBD
TBD
V min to V max
ppm/°C max
µV p-p typ
nV/√Hz typ
ppm/500 hr typ
ppm/1000 hr typ
nF max
mA typ
mA typ
ppm/V typ
ppm/mA
ppm
@ 25°C
2
0.8
V min
V max
Parameter
Output Current Ranges
ACCURACY
Resolution
Total Unadjusted Error (TUE)
TUE TC3
Relative Accuracy (INL)
Full-Scale TC3
OUTPUT CHARACTERISTICS3
Current Loop Compliance Voltage
Output Current Drift vs. Time
Resistive Load
Inductive Load
DC PSRR
Output Impedance
REFERENCE INPUT/OUTPUT
Reference Input3
Reference Input Voltage
DC Input Impedance
Reference Range
Reference Output
Output Voltage
Reference TC
Output Noise (0.1 Hz to 10 Hz)3
Noise Spectral Density3
Output Voltage Drift vs. Time3
Capacitive Load
Load Current
Short Circuit Current
Line Regulation3
Load Regulation3
Thermal Hysteresis3
DIGITAL INPUTS3
VIH, Input High Voltage
VIL, Input Low Voltage
AD5410
AD5420
Guaranteed monotonic
@ 25°C, error at other temperatures obtained using gain
TC
@ 25°C, error at other temperatures obtained using gain
TC
@ 10 kHz
DVCC = 2.7 V to 5.5 V, JEDEC compliant
Rev. PrE | Page 4 of 30
Preliminary Technical Data
Parameter
Input Current
Pin Capacitance
DIGITAL OUTPUTS 3
SDO
VOL, Output Low Voltage
VOH, Output High Voltage
High Impedance Leakage
Current
High Impedance Output
Capacitance
FAULT
VOL, Output Low Voltage
VOL, Output Low Voltage
VOH, Output High Voltage
POWER REQUIREMENTS
AVDD
DVCC
Input Voltage
Output Voltage
Output Load Current
Short Circuit Current
AIDD
DICC
Power Dissipation
AD5410/AD5420
Value2
±1
10
Unit
µA max
pF typ
Test Conditions/Comments
Per pin
Per pin
0.4
DVCC − 0.5
±1
V max
V min
µA max
sinking 200 µA
sourcing 200 µA
5
pF typ
0.4
0.6
3.6
V max
V typ
V min
10kΩ pull-up resistor to DVCC
@ 2.5 mA
10kΩ pull-up resistor to DVCC
10.8 to 60
10.8 to 40
V min to V max
V min to V max
AD5410/AD5420ACPZ
AD5410/AD5420AREZ
2.7 to 5.5
4.5
5
20
TBD
1
TBD
TBD
TBD
V min to V max
V typ
mA typ
mA typ
mA
mA max
mW typ
mW typ
mW typ
Internal supply disabled
DVCC can be overdriven up to 5.5V
1
VIH = DVCC, VIL = GND, TBD mA typ
AVDD = 40V
AVDD = 60V
AVDD = 15V
Maximum supply for the AD5410/AD5420BREZ is 40V, Maximum supply for the AD5410/AD5420BCPZ is 60V
Temperature range: -40°C to +85°C; typical at +25°C.
3
Guaranteed by design and characterization, not production tested.
2
Rev. PrE | Page 5 of 30
AD5410/AD5420
Preliminary Technical Data
AC PERFORMANCE CHARACTERISTICS
AVDD = 10.8V to 40V/60V1, AGND = DGND = 0 V, REFIN= +5 V external; DVCC = 2.7 V to 5.5 V, RL = 300Ω, HL = 50mH;
all specifications TMIN to TMAX, 0 to 24 mA range unless otherwise noted.
Table 3.
Parameter2
DYNAMIC PERFORMANCE
Output Current Settling Time
AC PSRR
1
2
TBD
TBD
TBD
Unit
Test Conditions/Comments
µs typ
µs typ
dB
To 0.1% FSR , L = 1H
To 0.1% FSR , L < 1mH
200mV 50/60 Hz sinewave
superimposed on power supply voltage
Maximum supply for the AD5410/AD5420BREZ is 40V, Maximum supply for the AD5410/AD5420BCPZ is 60V
Guaranteed by design and characterization, not production tested.
Rev. PrE | Page 6 of 30
Preliminary Technical Data
AD5410/AD5420
TIMING CHARACTERISTICS
AVDD = 10.8V to 40V/60V1, AGND = DGND = 0 V, REFIN= +5 V external; DVCC = 2.7 V to 5.5 V, RL = 300Ω, HL = 50mH;
all specifications TMIN to TMAX, 0 to 24 mA range unless otherwise noted.
Table 4.
Parameter2, 3, 4
Write Mode
t1
t2
t3
t4
t5
t5
t6
t7
t8
t9
t10
Readback Mode
t11
t12
t13
t14
t15
t16
t17
t18
t19
t20
Daisychain Mode
t21
t22
t23
t24
t25
t26
t27
t28
t29
Limit at TMIN, TMAX
Unit
Description
33
13
13
13
40
5
5
5
40
20
5
ns min
ns min
ns min
ns min
ns min
µs min
ns min
ns min
ns min
ns min
µs max
SCLK cycle time
SCLK low time
SCLK high time
LATCH delay time
LATCH high time
LATCH high time (After a write to the CONTROL register)
Data setup time
Data hold time
LATCH low time
CLEAR pulsewidth
CLEAR activation time
82
33
33
13
40
5
5
40
40
33
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns max
ns max
SCLK cycle time
SCLK low time
SCLK high time
LATCH delay time
LATCH high time
Data setup time
Data hold time
LATCH low time
Serial output delay time (CL SDO5 = 15pF)
LATCH rising edge to SDO tri-state
82
33
33
13
40
5
5
40
40
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns max
SCLK cycle time
SCLK low time
SCLK high time
LATCH delay time
LATCH high time
Data setup time
Data hold time
LATCH low time
Serial output delay time (CL SDO5 = 15pF)
1
Maximum supply for the AD5410/AD5420AREZ is 40V, Maximum supply for the AD5410/AD5420ACPZ is 60V
Guaranteed by characterization. Not production tested.
3
All input signals are specified with tR = tF = 5 ns (10% to 90% of DVCC) and timed from a voltage level of 1.2 V.
4
See Figure 2, Figure 3, and Figure 4.
5
CL SDO = Capacitive load on SDO output.
2
Rev. PrE | Page 7 of 30
AD5410/AD5420
Preliminary Technical Data
t1
SCLK
1
2
24
t3
t2
t4
t5
LATCH
t7
t6
SDIN
t8
DB23
DB0
t9
CLEAR
t10
OUTPUT
Figure 2. Write Mode Timing Diagram
t11
SCLK
1
2
t12
2
1
24
t13
t14
8
9
23
22
24
t15
LATCH
t16
SDIN
t17
t18
DB23
DB0
DB23
DB0
NOP CONDITION
INPUT WORD SPECIFIES
REGISTER TO BE READ
t 20
t 19
SDO
X
UNDEFINED DATA
X
X
X
DB15
FIRST 8 BITS ARE
DON’T CARE BITS
DB0
SELECTED REGISTER
DATA CLOCKED OUT
Figure 3. Readback Mode Timing Diagram
t21
SCLK
1
2
25
24
26
48
t22
t23
t24
LATCH
t26
SDIN
DB23
DB0
INPUT WORD FOR DAC N
SDO
DB23
DB23
t28
DB0
INPUT WORD FOR DAC N-1
t 29
DB0
t27
DB23
UNDEFINED
DB0
INPUT WORD FOR DAC N
Figure 4. Daisychain Mode Timing Diagram
Rev. PrE | Page 8 of 30
t25
Preliminary Technical Data
AD5410/AD5420
ABSOLUTE MAXIMUM RATINGS
TA = 25°C unless otherwise noted.
Transient currents of up to 100 mA do not cause SCR latch-up.
Table 5.
Parameter
AVDD to AGND, DGND
DVCC to AGND, DGND
Digital Inputs to AGND, DGND
Digital Outputs to AGND, DGND
REFIN/REFOUT to AGND, DGND
IOUT to AGND, DGND
AGND to DGND
Operating Temperature Range
Industrial
Storage Temperature Range
Junction Temperature (TJ max)
24-Lead TSSOP Package
θJA Thermal Impedance
40-Lead LFCSP Package
θJA Thermal Impedance
Power Dissipation
Lead Temperature
Soldering
Rating
−0.3V to 60V
−0.3 V to +7 V
−0.3 V to DVCC + 0.3 V or 7 V
(whichever is less)
−0.3 V to DVCC + 0.3 V or 7V
(whichever is less)
−0.3 V to +7 V
−0.3V to AVDD
-0.3V to +0.3V
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
−40°C to +851°C
−65°C to +150°C
125°C
42°C/W
28°C/W
(TJ max – TA)/ θJA
JEDEC Industry Standard
J-STD-020
1
Power dissipated on chip must be de-rated to keep junction temperature
below 125°C. Assumption is max power dissipation condition is sourcing
24mA into Ground from AVDD with a 3mA on-chip current.
Rev. PrE | Page 9 of 30
Preliminary Technical Data
AD5410/AD5420
36
NC
37
NC
AVDD
38
NC
GND
39
NC
NC
40
NC
NC
DVCC
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
35
34
33
32
31
GND
1
24
AVDD
DVCC
2
23
NC
FAULT
3
22
NC
FAULT 2
29 CAP2
GND
4
21
NC
GND 3
28 CAP1
GND
5
CLEAR
6
AD5420
NC 1
GND 4
20 BOOST
TOP VIEW
(Not to Scale) 19 I OUT
LATCH 7
18
NC
30 NC
27 BOOST
CLEAR 5
AD5420
26 IOUT
LATCH 6
TOP VIEW
(Not to Scale)
25 NC
SCLK 7
24 NC
SCLK
8
17
NC
SDIN 8
23 DVCC SELECT
SDIN
9
16
DVCC SELECT
SDO 9
22 NC
SDO 10
15
REFIN
AGND 11
14
REFOUT
GND 12
13
RSET
NC 10
Figure 5. TSSOP Pin Configuration
15
16
17
NC
DGND
GND
GND
RSET
REFOUT
18
19
20
NC
14
NC
13
REFIN
12
AGND
21 NC
11
Figure 6. LFCSP Pin Configuration
Table 6. Pin Function Descriptions
TSSOP Pin No.
1,4,5,12
2
3
LFCSP Pin No.
3,4,15,14,37
39
2
Mnemonic
GND
DVCC
FAULT
17,18,21,22, 23
NC
6
1,10,11,19,
20,21,22,24,25,
30,31,32,33,34,
35,38,40
5
7
6
LATCH
8
7
SCLK
9
10
8
9
SDIN
SDO
11
N/A
12
13
AGND
DGND
13
16
RSET
14
15
17
18
REFOUT
REFIN
16
23
DVCC
SELECT
19
20
26
27
IOUT
BOOST
N/A
N/A
24
Paddle
28
29
36
Paddle
CAP1
CAP2
AVDD
AGND
CLEAR
Description
These pins must be connected to 0V.
Digital Supply Pin. Voltage ranges from 2.7 V to 5.5 V.
Fault alert, This pin is asserted low when an open circuit is detected in current mode or
an over temperature is detected. Open drain output, must be connected to a pull-up
resistor.
No Connection.
Active High Input. Asserting this pin will set the current output to the bottom of the
selected range.
Positive edge sensitive latch, a rising edge will parallel load the input shift register data
into the DAC register, also updating the output.
Serial Clock Input. Data is clocked into the shift register on the rising edge of SCLK. This
operates at clock speeds up to 30 MHz.
Serial Data Input. Data must be valid on the rising edge of SCLK.
Serial Data Output. Used to clock data from the serial register in daisy-chain or readback
mode. Data is clocked out on the falling edge of SCLK. See Figure 3 and Figure 4.
Ground reference pin for analog circuitry.
Ground reference pin for digital circuitry. (AGND and DGND are internally connected in
TSSOP package).
An external, precision, low drift 15kΩ current setting resistor can be connected to this
pin to improve the IOUT temperature drift performance. Refer to Features section.
Internal Reference Voltage Output. REFOUT = 5 V ± 2 mV.
External Reference Voltage Input. Reference input range is 4 V to 5 V. REFIN = 5 V for
specified performance.
This pin when connected to GND disables the internal supply and an external supply
must be connected to the DVCC pin. Leave this pin unconnected to enable the internal
supply. Refer to features section.
Current output pin.
Optional external transistor connection. Connecting an external transistor will reduce
the power dissipated in the AD5410/AD5420. Refer to the features section.
Connection for optional output filtering capacitor. Refer to Features section.
Connection for optional output filtering capacitor. Refer to Features section.
Positive Analog Supply Pin. Voltage ranges from 10.8V to 40V/60V.
Ground reference for analog circuitry.
Rev. PrE | Page 10 of 30
Preliminary Technical Data
AD5410/AD5420
TYPICAL PERFORMANCE CHARACTERISTICS
Figure 7. Integral Non Linearity vs. Code
Figure 10. Integral Non Linearity vs. Temperature
Figure 8.Differential Non Linearity vs. Code
Figure 11. Differential Non Linearity vs. Temperature
Figure 9. Total Unadjusted Error vs. Code
Figure 12. Integral Non Linearity vs. Supply
Rev. PrE | Page 11 of 30
AD5410/AD5420
Preliminary Technical Data
Figure 13. Differential Non Linearity vs. Supply Voltage
Figure 16. Total Unadjusted Error vs. Reference Voltage
Figure 14. Integral Non Linearity vs. Reference Voltage
Figure 17. Total Unadjusted Error vs. Supply Voltage
Figure 15. Differential Non Linearity vs. Reference Voltage
Figure 18. Offset Error vs. Temperature
Rev. PrE | Page 12 of 30
Preliminary Technical Data
AD5410/AD5420
Figure 19. Gain Error vs. Temperature
Figure 21. IOUT vs. Time on Power-up
Figure 20. Voltage Compliance vs. Temperature
Figure 22. IOUT vs. Time on Output Enabled
Figure 23. DICC vs.Logic Input Voltage
Figure 24. AIDD vs AVDD
Rev. PrE | Page 13 of 30
AD5410/AD5420
Preliminary Technical Data
Figure 25. DVCC Output Voltage vs. DICC Load Current
Figure 28. Refout Output Noise (100kHz Bandwidth)
Figure 26. Refout Turn-on Transient
Figure 29. Refout Line Transient
Figure 27. Refout Output Noise (0.1Hz to 10Hz Bandwidth)
Figure 30. Refout Load Transient
Rev. PrE | Page 14 of 30
Preliminary Technical Data
AD5410/AD5420
Figure 31. Refout Histogram of Thermal Hysteresis
Figure 32. Refout Voltage vs. Load Current
Rev. PrE | Page 15 of 30
AD5410/AD5420
Preliminary Technical Data
TERMINOLOGY
Relative Accuracy or Integral Nonlinearity (INL)
For the DAC, relative accuracy, or integral nonlinearity (INL), is
a measure of the maximum deviation, in LSBs, from a straight
line passing through the endpoints of the DAC transfer
function. A typical INL vs. code plot can be seen in Figure 7
Total Unadjusted Error
Total unadjusted error (TUE) is a measure of the output error
taking all the various errors into account, namely INL error,
offset error, gain error, and output drift over supplies,
temperature, and time. TUE is expressed in % FSR.
Differential Nonlinearity (DNL)
Differential nonlinearity (DNL) is the difference between the
measured change and the ideal 1 LSB change between any two
adjacent codes. A specified differential nonlinearity of ±1 LSB
maximum ensures monotonicity. This DAC is guaranteed
monotonic by design. A typical DNL vs. code plot can be seen
in Figure 8.
Current Loop Voltage Compliance
The maximum voltage at the IOUT pin for which the output
currnet will be equal to the programmed value.
Monotonicity
A DAC is monotonic if the output either increases or remains
constant for increasing digital input code. The AD5724R/
AD5734R/AD5754R are monotonic over their full operating
temperature range.
Reference TC is a measure of the change in the reference output
voltage with a change in temperature. It is expressed in ppm/°C.
Full-Scale Error
Full-Scale error is a measure of the output error when full-scale
code is loaded to the DAC register. Ideally, the output should be
full-scale − 1 LSB. Full-scale error is expressed in percent of
full-scale range (% FSR).
Zero-Scale TC
This is a measure of the change in zero-scale error with a change in
temperature. Zero-scale error TC is expressed in ppm FSR/°C.
Gain Error
This is a measure of the span error of the DAC. It is the
deviation in slope of the DAC transfer characteristic from ideal
expressed in % FSR. A plot of gain error vs. temperature can be
seen in Table TBD
Gain TC
This is a measure of the change in gain error with changes in
temperature. Gain Error TC is expressed in ppm FSR/°C.
Power Supply Rejection Ratio (PSRR)
PSRR indicates how the output of the DAC is affected by
changes in the power supply voltage.
Reference TC
Line Regulation
Line regulation is the change in reference output voltage due to
a specified change in supply voltage. It is expressed in ppm/V.
Load Regulation
Load regulation is the change in reference output voltage due to
a specified change in load current. It is expressed in ppm/mA.
Thermal Hysteresis
Thermal hysteresis is the change of reference output voltage
after the device is cycled through temperatures from +25°C to
−40°C to +85°C and back to +25°C. This is a typical value from
a sample of parts put through such a cycle. See Table TBDfor a
histogram of thermal hysteresis.
VO _ HYS = VO (25° C) − VO _ TC
VO _ HYS ( ppm) =
VO (25° C) − VO _ TC
VO (25° C)
× 10 6
where:
VO(25°C) = VO at 25°C
VO_TC = VO at 25°C after temperature cycle
Rev. PrE | Page 16 of 30
AD5410/AD5420
Preliminary Technical Data
THEORY OF OPERATION
The AD5410/AD5420 is a precision digital to current loop
output converter designed to meet the requirements of
industrial process control applications. It provides a high
precision, fully integrated, low cost single-chip solution for
generating current loop outputs. The current ranges available
are; 0 to 20mA, 0 to 24mA and 4 to 20mA, The desired output
configuration is user selectable via the CONTROL register.
Reference Buffers
ARCHITECTURE
The AD5410/AD5420 is controlled over a versatile 3-wire serial
interface that operates at clock rates up to 30 MHz. It is
compatible with SPI®, QSPI™, MICROWIRE™, and DSP
standards.
The DAC core architecture of the AD5410/AD5420 consists of
two matched DAC sections. A simplified circuit diagram is
shown in Figure 33. The 4 MSBs of the 12/16-bit data word are
decoded to drive 15 switches, E1 to E15. Each of these switches
connects 1 of 15 matched resistors to either ground or the
reference buffer output. The remaining 8/12 bits of the dataword drive switches S0 to S11 of a 8/12-bit voltage mode R-2R
ladder network.
VOUT
2R
2R
2R
2R
2R
2R
2R
S0
S1
S7/S11
E1
E2
E15
The AD5410/AD5420 can operate with either an external or
internal reference. The reference input has an input range of 4 V
to 5 V, 5 V for specified performance. This input voltage is then
buffered before it is applied to the DAC.
SERIAL INTERFACE
Input Shift Register
The input shift register is 24 bits wide. Data is loaded into the
device MSB first as a 24-bit word under the control of a serial
clock input, SCLK. Data is clocked in on the rising edge of
SCLK. The input register consists of 8 control bits and 16 data
bits as shown in
VREF
8/12-BIT R-2R LADDER
FOUR MSBs DECODED INTO
15 EQUAL SEGMENTS
Figure 33. DAC Ladder Structure
The voltage output from the DAC core is converted to a current
(see diagram, Figure 34) which is then mirrored to the supply
rail so that the application simply sees a current source output
with respect to ground.
AV DD
R2
R3
T2
12/16-BIT
DAC
A2
T1
A1
IOUT
R1
Figure 34. Voltage to Current conversion circuitry
Rev. PrE | Page 17 of 30
AD5410/AD5420
Preliminary Technical Data
Table 7. The 24 bit word is unconditionally latched on the rising
edge of LATCH. Data will continue to be clocked in irrespective
of the state of LATCH, on the rising edge of LATCH the data
that is present in the input register will be latched, in other
words the last 24 bits to be clocked in before the rising edge of
LATCH will be the data that is latched. The timing diagram for
this operation is shown in Figure 2.
Rev. PrE | Page 18 of 30
Preliminary Technical Data
AD5410/AD5420
Table 7. Input Shift Register Format
MSB
D23
D22
D21
D20 D19 D18
ADDRESS WORD
D17
D16
D15
D14
D13
D12
D11
01010101
01010110
D9 D8 D7
DATA WORD
CONTROLLER
Table 8. Address Word Functions
Address
Word
00000000
00000001
00000010
D10
Function
DATA OUT
No Operation (NOP)
DATA Register
Readback register value as per Read Address
(See Table 10)
CONTROL Register
RESET Register
D6
D5
D4
D3
D2
AD5410/
AD5420*
SDIN
SERIAL CLOCK
SCLK
CONTROL OUT
LATCH
DATA IN
SDO
SDIN
AD5410/
AD5420*
Standalone Operation
The serial interface works with both a continuous and noncontinuous serial clock. A continuous SCLK source can only be
used if LATCH is taken high after the correct number of data
bits have been clocked in. In gated clock mode, a burst clock
containing the exact number of clock cycles must be used, and
LATCH must be taken high after the final clock to latch the
data. The first rising edge of SCLK that clocks in the MSB of the
dataword marks the beginning ot the write cycle. Exactly 24
rising clock edges must be applied to SCLK before LATCH is
brought high. If LATCH is brought high before the 24th rising
SCLK edge, the data written will be invalid. If more than 24
rising SCLK edges are applied before LATCH is brought high,
the input data will also be invalid.
SCLK
LATCH
SDO
SDIN
AD5410/
AD5420*
SCLK
LATCH
SDO
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 35. Daisy Chaining the AD5410/AD5420
Rev. PrE | Page 19 of 30
D1
LSB
D0
AD5410/AD5420
Preliminary Technical Data
Daisy-Chain Operation
must be used, and LATCH must be taken high after the final
clock to latch the data. See Figure 4 for a timing diagram.
For systems that contain several devices, the SDO pin can be
used to daisy chain several devices together as shown in Figure
35. This daisy-chain mode can be useful in system diagnostics
and in reducing the number of serial interface lines. Daisychain
mode is enabled by setting the DCEN bit of the CONTROL
register. The first rising edge of SCLK that clocks in the MSB of
the dataword marks the beginning of the write cycle. SCLK is
continuously applied to the input shift register. If more than 24
clock pulses are applied, the data ripples out of the shift register
and appears on the SDO line. This data is valid on the rising
edge of SCLK having been clocked out on the previous falling
SCLK edge. By connecting the SDO of the first device to the
SDIN input of the next device in the chain, a multidevice
interface is constructed. Each device in the system requires 24
clock pulses. Therefore, the total number of clock cycles must
equal 24 × N, where N is the total number of AD5410/AD5420
devices in the chain. When the serial transfer to all devices is
complete, LATCH is taken high. This latches the input data in
each device in the daisy chain. The serial clock can be a
continuous or a gated clock.
Readback Operation
Readback mode is invoked by setting the address word and read
address as shown in Table 9 and Table 10 when writing to the
input register. The next write to the AD5410/AD5420 should be
a NOP command which will clock out the data from the
previously addressed register as shown in Figure 3.
By default the SDO pin is disabled, after having addressed the
AD5410/AD5420 for a read operation, a rising edge on LATCH
will enable the SDO pin in anticipation of data being clocked
out, after the data has been clocked out on SDO, a rising edge
on LATCH will disable (tri-state) the SDO pin once again.
To read back the data register for example, the following
sequence should be implemented:
1.
2.
A continuous SCLK source can only be used if LATCH is taken
high after the correct number of clock cycles. In gated clock
mode, a burst clock containing the exact number of clock cycles
Write 0x020001 to the AD5410/AD5420 input register.
This configures the part for read mode with the data
register selected.
Follow this with a second write, a NOP condition, 0x000000
During this write, the data from the register is clocked out
on the SDO line.
Table 9. Input Shift Register Contents for a read operation
MSB
D23
D22
D21
D20
D19
D18
D17
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
0
0
0
0
0
0
1
0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Table 10. Read Address Decoding
Read Address
00
01
10
Function
Read Status Register
Read Data Register
Read Control Register
Rev. PrE | Page 20 of 30
LSB
D1
D0
Read
Address
Preliminary Technical Data
AD5410/AD5420
POWER-UP STATE
⎡ 20mA ⎤
I OUT = ⎢ N ⎥ × D
⎣ 2 ⎦
On power-up of the AD5410/AD5420, the power-on-reset
circuit ensures that all registers are loaded with zero-code, as
such the output will be disabled (tri-state).
⎡ 24mA ⎤
I OUT = ⎢ N ⎥ × D
⎣ 2 ⎦
TRANSFER FUNCTION
For the 0 to 20mA, 0 to 24mA and 4 to 20mA current output
ranges the output current is respectively expressed as;
⎡16mA ⎤
I OUT = ⎢ N ⎥ × D + 4mA
⎣ 2 ⎦
where:
D is the decimal equivalent of the code loaded to the DAC.
N is the bit resolution of the DAC.
DATA REGISTER
The DATA register is addressed by setting the control word of the input shift register to 0x01. The data to be written to the DATA register
is entered in positions D15 to D4 for the AD5410 and D15 to D0 for the AD5420 as shown in Table 11 and Table 12.
Table 11. Programming the AD5410 Data Register
MSB
D15
D14
D13
D12
D7
D6
D5
D4
D3
X
D2
X
D1
X
LSB
D0
X
D9
D8
D7
16-BIT DATA WORD
D6
D5
D4
D3
D2
D1
LSB
D0
D11
D10
D9
12-BIT DATA WORD
D8
Table 12. Programming the AD5420 Data Register
MSB
D15
D14
D13
D12
D11
D10
CONTROL REGISTER
The CONTROL register is addressed by setting the control word of the input shift register to 0x55. The data to be written to the
CONTROL register is entered in positions D15 to D0 as shown in Table 13. The CONTROL register functions are shown in Table 14.
Table 13. Programming the CONTROL Register
MSB
D15
0
D14
0
D13
REXT
D12
OUTEN
D11
D10
D9
SR CLOCK
D8
D7
D6
D5
SR STEP
D4
SREN
D3
DCEN
D2
R2
Table 14. Control Register Functions
Option
REXT
OUTEN
SR CLOCK
SR STEP
SREN
DCEN
R2,R1,R0
Description
Setting this bit selects the external current
setting resistor, Further details in Features
section
Output enable. This bit must be set to enable
the output.
See Features Section. Digital Slew Rate Control
See Features Section. Digital Slew Rate Control
Digital Slew Rate Control enable
Daisychain enable
Output range select. See Table 15
Table 15. Output Range Options
R2
1
1
1
Rev. PrE | Page 21 of 30
R1
0
1
1
R0
1
0
1
Output Range Selected
4 to 20 mA Current Range
0 to 20 mA Current Range
0 to 24 mA Current Range
D1
R1
LSB
D0
R0
AD5410/AD5420
Preliminary Technical Data
RESET REGISTER
The RESET register is addressed by setting the control word of the input shift register to 0x56. The data to be written to the RESET
register is entered in positions D15 to D0 as shown in Table 16. The RESET register options are shown in Table 16 and Table 17.
Table 16. Programming the CONTROL 2 Register
MSB
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
LSB
D0
RESET
Table 17. Control 2 register Functions
Option
RESET
Description
Setting this bit performs a reset operation, restoring the AD5410/AD5420 to its initial power on state
STATUS REGISTER
The STATUS register is a read only register. The STATUS register functionality is shown in Table 18 and Table 19.
Table 18. Decoding the STATUS Register
MSB
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
IOUT FAULT
Table 19. STATUS Register Functions
Option
IOUT FAULT
SLEW ACTIVE
OVER TEMP
Description
This bit will be set if a fault is detected on the IOUT pin.
This bit will be set while the output value is slewing (slew rate control enabled)
This bit will be set if the AD5410/AD5420 core temperature exceeds approx. 150°C.
Rev. PrE | Page 22 of 30
D1
SLEW ACTIVE
LSB
D0
OVER TEMP
Preliminary Technical Data
AD5410/AD5420
FEATURES
FAULT ALERT
EXTERNAL CURRENT SETTING RESISTOR
The AD5410/AD5420 is equipped with a FAULT pin, this is an
open-drain output allowing several AD5410/AD5420 devices to
be connected together to one pull-up resistor for global fault
detection. The FAULT pin is forced active by any one of the
following fault scenarios;
Referring to Figure 34, R1 is an internal sense resistor as part of
the voltage to current conversion circuitry. The stability of the
output current over temperature is dependent on the stability of
the value of R1. As a method of improving the stability of the
output current over temperature an external precision 15kΩ low
drift resistor can be connected to the RSET pin of the
AD5410/AD5420 to be used instead of the internal resistor R1.
The external resistor is selected via the CONTROL 1 register.
See Table 13.
1)
2)
The Voltage at IOUT attempts to rise above the
compliance range, due to an open-loop circuit or
insufficient power supply voltage. The IOUT current is
controlled by a PMOS transistor and internal
amplifier as shown in Figure 34. The internal circuitry
that develops the fault output avoids using a
comparator with “window limits” since this would
require an actual output error before the FAULT
output becomes active. Instead, the signal is generated
when the internal amplifier in the output stage has less
than approxiamately one volt of remaining drive
capability (when the gate of the output PMOS
transistor nearly reaches ground). Thus the FAULT
output activates slightly before the compliance limit is
reached. Since the comparison is made within the
feedback loop of the output amplifier, the output
accuracy is maintained by its open-loop gain and an
output error does not occur before the FAULT output
becomes active.
If the core temperature of the AD5410/AD5420
exceeds approx. 150°C.
The OPEN CCT and OVER TEMP bits of the STATUS register
are used in conjunction with the FAULT pin to inform the user
which one of the fault conditions caused the FAULT pin to be
asserted. See Table 18 and Table 19.
ASYNCHRONOUS CLEAR (CLEAR)
CLEAR is an active high clear that clears the Current output to
the bottom of its programmed range. It is necessary to maintain
CLEAR high for a minimum amount of time (see Figure 2) to
complete the operation. When the CLEAR signal is returned
low, the output remains at the cleared value. The pre-clear value
can be restored by pulsing the LATCH signal low without
clocking any data. A new value cannot be programmed until the
CLEAR pin is returned low.
DIGITAL POWER SUPPLY
By default, the DVCC pin accepts a power supply of 2.7V to 5.5V,
alternatively, via the DVCC SELECT pin an internal 4.5V power
supply may be output on the DVCC pin for use as a digital power
supply for other devices in the system or as a termination for
pull-up resistors. This facility offers the advantage of not having
to bring a digital supply across an isolation barrier. The internal
power supply is enabled by leaving the DVCC SELECT pin
unconnected. To disable the internal supply DVCC SELECT
should be tied to 0V. DVCC is capable of supplying up to 5mA
of current, for a load regulation graph see Figure TBD.
EXTERNAL BOOST FUNCTION
The addition of an external boost transistor as shown in Figure
36 will reduce the power dissipated in the AD5410/AD5420 by
reducing the current flowing in the on-chip output transistor
(dividing it by the current gain of the external circuit). A
discrete NPN transistor with a breakdown voltage, BVCEO,
greater than 60V can be used.
The external boost capability has been developed for those
users who may wish to use the AD5410/AD5420 at the
extremes of the supply voltage, load current and temperature
range. The boost transistor can also be used to reduce the
amount of temperature induced drift in the part. This will
minimise the temperature induced drift of the on-chip voltage
reference, which improves drift and linearity.
MJD31C
OR
2N3053
BOOST
AD5410/
AD5420
IOUT
INTERNAL REFERENCE
1k
The AD5410/AD5420 contains an integrated +5V voltage
reference with initial accuracy of ±2mV max and a temperature
drift coefficient of ±10 ppm max. The reference voltage is
buffered and externally available for use elsewhere within the
system. See Figure 32 for a load regulation graph of the
Integrated reference.
Rev. PrE | Page 23 of 30
0.022 F
Figure 36. External Boost Configuration
RLOAD
AD5410/AD5420
Preliminary Technical Data
DIGITAL SLEW RATE CONTROL
The Slew Rate Control feature of the AD5410/AD5420 allows
the user to control the rate at which the output current changes.
With the slew rate control feature disabled the output currrent
will change at a rate limited by the output drive circuitry and
the attached load. If the user wishes to reduce the slew rate this
can be achieved by enabling the slew rate control feature.With
the feature enabled via the SREN bit of the CONTROL register,
(See Table 13) the output, instead of slewing directly between
two values, will step digitally at a rate defined by two
parameters accessible via the CONTROL register as shown in
Table 13. The parameters are SR CLOCK and SR STEP. SR
CLOCK defines the rate at which the digital slew will be
updated SR STEP defines by how much the output value will
change at each update. Together both parameters define the rate
of change of the output current.Table 20 and Table 21 outline
the range of values for both the SR CLOCK and SR STEP
parameters.
Table 20. Slew Rate Update Clock Options
SR CLOCK
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Update Clock Frequency (Hz)
257732
198413
152439
131579
115741
69444
37594
25773
20161
16026
10288
8278
6897
5525
Table 21. Slew Rate Step Size Options
SR STEP
000
001
010
011
100
101
110
111
AD5410 Step
Size (LSBs)
1
⁄16
⅛
¼
½
1
2
4
8
AD5420 Step
Size (LSBs)
1
2
4
8
16
32
64
128
The time it will take for the output current to slew over a given
output range can be expressed as follows.
SlewTime =
OutputChange
StepSize × UpdateClockFrequency × LSBSize
Where:
Slew Time is expressed in seconds
Output Change is expressed in Amps
When the slew rate control feature is enabled, all output
changes will change at the programmed slew rate, i.e. if the
CLEAR pin is asserted the output will slew to the clear value at
the programmed slew rate. The output can be halted at its
current value with a write to the CONTROL register. To avoid
halting the output slew, the SLEW ACTIVE bit can be read to
check that the slew has completed before writing to the
AD5410/AD5420 registers. See Table 18. The update clock
frequency for any given value will be the same for all output
ranges. The step size however will vary across output ranges for
a given value of step size as the LSB size will be different for
each output range. Table 22 shows the range of programmable
slew times for a full-scale change on any of the output ranges.
The values were obtained using the Slew Time equation above.
4237
3300
Rev. PrE | Page 24 of 30
Preliminary Technical Data
AD5410/AD5420
Update Clock Frequency (Hz)
Table 22. Programmable Slew Time values in seconds for a full scale change on any output range.
257732
198413
152439
131579
115741
69444
37594
25773
20161
16026
10288
8278
6897
5525
4237
3300
1
0.25
0.33
0.43
0.50
0.57
0.9
1.7
2.5
3.3
4.1
6.4
7.9
9.5
12
15
20
2
0.13
0.17
0.21
0.25
0.28
0.47
0.87
1.3
1.6
2.0
3.2
4.0
4.8
5.9
7.7
9.9
4
0.06
0.08
0.11
0.12
0.14
0.24
0.44
0.64
0.81
1.0
1.6
2.0
2.4
3.0
3.9
5.0
8
0.03
0.04
0.05
0.06
0.07
0.12
0.22
0.32
0.41
0.51
0.80
1.0
1.2
1.5
1.9
2.5
Step Size (LSBs)
16
0.016
0.021
0.027
0.031
0.035
0.06
0.11
0.16
0.20
0.26
0.40
0.49
0.59
0.74
0.97
1.24
32
0.008
0.010
0.013
0.016
0.018
0.03
0.05
0.08
0.10
0.13
0.20
0.25
0.30
0.37
0.48
0.62
64
0.004
0.005
0.007
0.008
0.009
0.015
0.03
0.04
0.05
0.06
0.10
0.12
0.15
0.19
0.24
0.31
alternative to the Digital Slew Rate Control feature or in
addition to it as a means of smoothing out the steps caused by
the digital code increments.
IOUT FILTERING CAPACITORS (LFCSP PACKAGE)
C1
Two capacitors may be placed between the pins CAP1, CAP2
and AVDD as shown in Figure 37.
C2
AVDD
CAP1
C1
CAP2
AV DD
C2
R3
AVDD
BOOST
R2
CAP1
AD5410/
AD5420
128
0.0020
0.0026
0.0034
0.0039
0.0044
0.007
0.014
0.020
0.025
0.03
0.05
0.06
0.07
0.09
0.12
0.16
CAP2
DAC
12.5K
40K
IOUT
GND
R1
Figure 37. IOUT Filtering Capacitors
These two pins are only available on the LFCSP package.The
capacitors form a filter on the current output circuitry as shown
in Figure 38, reducing the bandwidth and the rate of change of
the output current. These capacitors can be used as an
Rev. PrE | Page 25 of 30
Figure 38. IOUT Filter Ciruitry
IOUT
AD5410/AD5420
Preliminary Technical Data
APPLICATIONS INFORMATION
DRIVING INDUCTIVE LOADS
When driving inductive or poorly defined loads connect a
0.01µF capacitor between IOUT and GND. This will ensure
stability with loads beyond 50mH. There is no maximum
capacitance limit. The capacitive component of the load may
cause slower settling, The digital Slew Rate Control feature may
also prove useful in this situation.
TRANSIENT VOLTAGE PROTECTION
The AD5410/AD5420 contains ESD protection diodes which
prevent damage from normal handling. The industrial control
environment can, however, subject I/O circuits to much higher
transients. In order to protect the AD5410/AD5420 from
excessively high voltage transients , external power diodes and a
surge current limiting resistor may be required, as shown in
Figure 39. The constraint on the resistor value is that during
normal operation the output level at IOUT must remain within
its voltage compliance limit of AVDD – 2.5V and the two
protection diodes and resistor must have appropriate power
ratings. Further protection can be provided with Transient
Voltage Suppressors or Transorbs, these are available as both
unidirectional (protects against positive high voltage transients)
and bidirectional (protects against both positive and negative
high voltage transients) and are available in a wide range of
standoff and breakdown voltage ratings. It is recommended that
all field connected nodes are protected.
AVDD
AVDD
AD5410/
AD5420
IOUT
AGND
RP
RLOAD
ceramic types, which provide a low impedance path to ground
at high frequencies to handle transient currents due to internal
logic switching.
The power supply lines of the AD5410/AD5420 should use as
large a trace as possible to provide low impedance paths and
reduce the effects of glitches on the power supply line. Fast
switching signals such as clocks should be shielded with digital
ground to avoid radiating noise to other parts of the board and
should never be run near the reference inputs. A ground line
routed between the SDIN and SCLK lines helps reduce crosstalk
between them (not required on a multilayer board that has a
separate ground plane, but separating the lines helps). It is
essential to minimize noise on the REFIN line because it
couples through to the DAC output.
Avoid crossover of digital and analog signals. Traces on
opposite sides of the board should run at right angles to each
other. This reduces the effects of feed through the board. A
microstrip technique is by far the best, but not always possible
with a double-sided board. In this technique, the component
side of the board is dedicated to ground plane, while signal
traces are placed on the solder side.
GALVANICALLY ISOLATED INTERFACE
In many process control applications, it is necessary to provide
an isolation barrier between the controller and the unit being
controlled to protect and isolate the controlling circuitry from
any hazardous common-mode voltages that might occur. The
iCoupler® family of products from Analog Devices provides
voltage isolation in excess of 2.5 kV. The serial loading structure
of the AD5410/AD5420 make it ideal for isolated interfaces
because the number of interface lines is kept to a minimum.
Figure 40 shows a 4-channel isolated interface to the
AD5410/AD5420 using an ADuM1400. For further
information, visit http://www.analog.com/icouplers.
Figure 39. Output Transient Voltage Protection
LAYOUT GUIDELINES
Controller
In any circuit where accuracy is important, careful consideration
of the power supply and ground return layout helps to ensure
the rated performance. The printed circuit board on which the
AD5410/AD5420 is mounted should be designed so that the
analog and digital sections are separated and confined to certain
areas of the board. If the AD5410/AD5420 is in a system where
multiple devices require an AGND-to-DGND connection, the
connection should be made at one point only. The star ground
point should be established as close as possible to the device.
The AD5410/AD5420 should have ample supply bypassing of
10 µF in parallel with 0.1 µF on each supply located as close to
the package as possible, ideally right up against the device. The
10 µF capacitors are the tantalum bead type. The 0.1 µF
capacitor should have low effective series resistance (ESR) and
low effective series inductance (ESI) such as the common
Serial Clock Out
Serial Data Out
SYNC Out
Control out
ADuM1400 *
VIA
VIB
VIC
VID
ENCODE
ENCODE
ENCODE
ENCODE
DECODE
DECODE
DECODE
DECODE
VOA
VOB
VOC
VOD
To SCLK
To SDIN
To LATCH
To CLEAR
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 40. Isolated Interface
MICROPROCESSOR INTERFACING
Microprocessor interfacing to the AD5410/AD5420 is via a serial
bus that uses protocol compatible with microcontrollers and
DSP processors. The communications channel is a 3-wire
(minimum) interface consisting of a clock signal, a data signal,
Rev. PrE | Page 26 of 30
Preliminary Technical Data
AD5410/AD5420
and a latch signal. The AD5410/AD5420 require a 24-bit dataword with data valid on the rising edge of SCLK.
be controlled or AVDD should be reduced. The conditions will
depend on the device and package.
For all interfaces, the DAC output update is initiated on the
rising edge of LATCH. The contents of the registers can be read
using the readback function.
At maximum ambient temperature of 85°C the
AD5410/AD5420AREZ (24-lead TSSOP) can dissipate 950mW
and the AD5410/AD5420ACPZ (40-lead LFCSP) can dissipate
1.42W.
To ensure the junction temperature does not exceed 125°C
while driving the maximum current of 24mA directly into
ground (also adding an on-chip current of 3mA), AVDD should
be reduced from the maximum rating to ensure the package is
not required to dissipate more power than stated above. See
Table 23, Figure 41 and Figure 42.
THERMAL AND SUPPLY CONSIDERATIONS
The AD5410/AD5420 is designed to operate at a maximum
junction temperature of 125°C. It is important that the device is
not operated under conditions that will cause the junction
temperature to exceed this value . Excessive junction
temperature can occur if the AD5410/AD5420 is operated from
the maximum AVDD and driving the maximum current (24mA)
directly to ground. In this case the ambient temperature should
2.5
65
TSSOP
LFCSP
60
2
Supply Voltage (V)
Power Dissipation (W)
55
1.5
1
TSSOP
LFCSP
50
45
40
35
0.5
30
0
25
40
45
50
55
60
65
70
Ambient Temperature (°C)
75
80
85
25
35
45
55
65
75
85
Ambient Temperature (°C)
Figure 41. Maximum Power Dissipation Vs Ambient Temperature
Figure 42. Maximum Supply Voltage Vs Ambient Temperature
Table 23. Thermal and Supply considerations for each package
TSSOP
Maximum allowed power dissipation
when operating at an ambient
temperature of 85°C
Maximum allowed ambient
temperature when operating from a
supply of 40V/60V and driving 24mA
directly to ground.
Maximum allowed supply voltage
when operating at an ambient
temperature of 85°C and driving 24mA
directly to ground.
TJ max − TA
Θ JA
LFCSP
=
125 − 85
TJ max − TA
= 950 mW
Θ JA
42
(
)
TJ max − PD × Θ JA = 125 − 40 × 0.027 × 42 = 79°C
TJ max − TA
AI DD × Θ JA
=
125 − 85
0.027 × 42
= 35V
Rev. PrE | Page 27 of 30
=
125 − 85
= 1.42W
28
(
)
TJ max− PD × Θ JA = 125 − 60 × 0.027 × 28 = 79°C
TJ max − TA
AI DD × Θ JA
=
125 − 85
0.027 × 28
= 53V
AD5410/AD5420
Preliminary Technical Data
OUTLINE DIMENSIONS
5.02
5.00
4.95
7.90
7.80
7.70
24
13
4.50
4.40
4.30
3.25
3.20
3.15
EXPOSED
PAD
(Pins Up)
6.40 BSC
1
12
BOTTOM VIEW
TOP VIEW
1.05
1.00
0.80
0.15
0.05
SEATING
PLANE
0.10 COPLANARITY
8°
0°
0.20
0.09
0.30
0.19
0.65
BSC
0.75
0.60
0.45
050806-A
1.20 MAX
COMPLIANT TO JEDEC STANDARDS MO-153-ADT
Figure 43. 24-Lead Thin Shrink Small Outline Package, Exposed Pad [TSSOP_EP]
(RE-24)
Dimensions shown in millimeters
6.00
BSC SQ
0.60 MAX
0.60 MAX
31
30
PIN 1
INDICATOR
TOP
VIEW
0.50
BSC
5.75
BCS SQ
0.50
0.40
0.30
12° MAX
40
1
4.25
4.10 SQ
3.95
EXPOSED
PAD
(BOT TOM VIEW)
21
20
10
11
0.25 MIN
4.50
REF
0.80 MAX
0.65 TYP
0.05 MAX
0.02 NOM
SEATING
PLANE
0.30
0.23
0.18
0.20 REF
COPLANARITY
0.08
101306-A
1.00
0.85
0.80
PIN 1
INDICATOR
COMPLIANT TO JEDEC STANDARDS MO-220-VJJD-2
Figure 44. 40-Lead Lead Frame Chip Scale Package
(CP-40)
Dimensions shown in millimeters
ORDERING GUIDE
Model
AD5410AREZ
AD5410ACPZ
AD5420AREZ
AD5420ACPZ
Resolution
12 Bits
12 Bits
16 Bits
16 Bits
AVDD max
40V
60V
40V
60V
Temperature Range
-40°C to 85°C
-40°C to 85°C
-40°C to 85°C
-40°C to 85°C
Rev. PrE | Page 28 of 30
Package Description
24 Lead TSSOP_EP
40 Lead LFCSP
24 Lead TSSOP_EP
40 Lead LFCSP
Package Option
RE-24
CP-40
RE-24
CP-40
Preliminary Technical Data
AD5410/AD5420
Rev. PrE | Page 29 of 30
AD5410/AD5420
Preliminary Technical Data
NOTES
©2008 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
PR07027-0-5/08(PrE)
Rev. PrE | Page 30 of 30