2.5 V to 5.5 V supply operation
True 12-bit accuracy
5 V operation @ <1 μA
Fast 3-wire serial input
Fast 5 μs settling time
1.9 MHz, 4-quadrant multiply BW
Upgrade for
Standard and rotated pinout
APPLICATIONS
Ideal for PLC applications in industrial control
Programmable amplifiers and attenuators
Digitally controlled calibration and filters
Motion control systems
GENERAL DESCRIPTION
The AD5441 is an improved high accuracy 12-bit multiplying
digital-to-analog converter (DAC) in space-saving 8-lead
packages. Featuring serial input, double buffering, and excellent
analog performance, the AD5441 is ideal for applications where
PC board space is at a premium. Improved linearity and gain
error performance permit reduced part counts through the
elimination of trimming components. Separate input clock and
load DAC control lines allow full user control of data loading
and analog output.
The circuit consists of a 12-bit serial-in/parallel-out shift register, a
12-bit DAC register, a 12-bit CMOS DAC, and control logic.
Serial data is clocked into the input register on the rising edge of
the clock pulse. When the new data-word is clocked in, it is
loaded into the DAC register with the
DAC register is converted to an output current by the DAC.
Consuming only 1 µA from a single 5 V power supply, the
AD5441 is the ideal low power, small size, high performance
solution to many application problems.
The AD5441 is specified over the extended industrial (−40°C to
+125°C) temperature range. It is available in an 8-lead LFCSP
and an 8-lead MSOP.
DAC8043 and DAC8043A
LD
input pin. Data in the
Multiplying DAC
AD5441
FUNCTIONAL BLOCK DIAGRAM
V
DD
V
REF
LD
CLK
SRI
AD5441
DAC
12
DAC REG
12
12-BIT SHIFT
REGISTER
Figure 1.
R
FB
I
OUT
GND
06492-001
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
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.
Resolution N 12 Bits
Relative Accuracy INL ±0.5 LSB
Differential Nonlinearity DNL ±0.5 LSB All grades monotonic to 12 bits
Gain Error G
Gain Temperature Coefficient
Output Leakage Current I
±25 nA TA = –40°C, +125°C, data = 000H, I
Zero-Scale Error I
±0.15 LSB TA = −40°C, +125°C, data = 000H
REFERENCE INPUT
Input Resistance R
Input Capacitance
ANALOG OUTPUT
Output Capacitance
4 pF Data = FFFH
DIGITAL INPUTS
Digital Input Low VIL 0.8 V
Digital Input High VIH 2.4 V
Input Leakage Current IIL 1 μA V
Input Capacitance
AC CHARACTERISTICS
Output Current Settling Time tS 5 μs To ±0.01% of full-scale, external op amp OP42
0.5 μs To ±0.01% of full-scale, 100 Ω terminated to ground
DAC Glitch Q 40 nVs Data = 000H to FFFH to 000H, V
1 nVs Data = 000H to FFFH to 000H, V
Digital Feedthrough 5 nV Using external op amp OP42
Feedthrough (V
Total Harmonic Distortion THD −85 dB V
Output Noise Density en 17 nV/√Hz 10 Hz to 100 kHz between RFB and I
Multiplying Bandwidth BW 1.9 MHz −3 dB, V
SUPPLY CHARACTERISTICS
Power Supply Range V
Positive Supply Current IDD 10 μA V
Power Dissipation P
Power Supply Sensitivity PSS 0.002 %/% ΔVDD = ±5%
1
These parameters are guaranteed by design and not subject to production testing.
7 15 kΩ Absolute temperature coefficient < 50 ppm/°C
1
1
1
1
) FT 1.4 mV p-p V
OUT/VREF
1
REF
C
5 pF
REF
C
OUT
CIL 4.0 pF V
DD RANGE
DISS
±5 nA Data = 000H, I
1 pF Data = 000H
2.5 5.5 V
2.5 5.5 μW V
pin measured
OUT
pin measured
OUT
= 0 V to 5 V
LOGI C
= 0 V
LOGI C
REF
REF
= 20 V p-p, data = 000H, f = 10 kHz
REF
= 6 V rms, data = FFFH, f = 1 kHz
REF
, V
= 100 mV rms, data = FFFH
REF
= 0 V or VDD
LOGI C
= 0 V or VDD
LOGI C
OUT/VREF
pin measured
OUT
= 0 V, OP42
= 0 V, 100 Ω
OUT
Rev. 0 | Page 3 of 16
AD5441
TIMING CHARACTERISTICS
All input control signals are specified with tR = tF = 2 ns (10% to 90% of VDD) and timed from a voltage level of (VIL + VIH)/2; VDD + 2.5 V
to 5.5 V, V
Table 2. Timing Characteristics
Parameter 2.5 V 5.5 V Unit Conditions/Comments
t
DS
t
DH
t
CH
t
CL
t
LD
t
LD1
t
ASB
= 10 V; temperature range = −40°C to +125°C; all specifications T
REF
10 5 ns min Data setup
5 5 ns min Data hold
15 10 ns min Clock width high
15 10 ns min Clock width low
20 10 ns min Load pulse width
0 0 ns min
0 0 ns min
LD DAC high to MSB CLK high
LSB CLK to
to T
MIN
LD DAC
, unless otherwise noted.
MAX
SRI
CLK
LD
SRI
CLK
LD
FS
V
OUT
ZS
D11 D10D9D8D6D5 D4D3D2D1D0D7
t
LD1
DATA LOADED MSB(D11) FIRSTDAC REGISTER L OAD
t
CL
Dxx
tDSt
t
ASB
DH
t
CH
t
LD
±1LSB
ERROR BAND
6492-005
Figure 2. Timing Diagram
Table 3. Control Logic Truth Table
CLK
1
↑
↑
LD
H Shift register data advanced one bit Latched
L Shift register data advanced one bit Transparent
Serial Shift Register Function DAC Register Function
H or L L No effect Updated with current shift register contents
L
1
equals positive logic transition. ↑
1
↑
No effect Latched all 12 bits
Rev. 0 | Page 4 of 16
AD5441
ABSOLUTE MAXIMUM RATINGS
Table 4.
Parameter Rating
VDD to GND −0.3 V, +8 V
V
to GND ±18 V
REF
RFB to GND ±18 V
Logic Inputs to GND −0.3 V, VDD + 0.3 V
I
to GND −0.3 V, VDD + 0.3 V
OUT
I
Short Circuit to GND 50 mA
OUT
Package Power Dissipation (TJ max − TA)/θ
JA
Maximum Junction Temperature (TJ max) 150°C
Operating Temperature Range −40°C to +125°C
Storage Temperature Range −65°C to +150°C
Lead Temperature (Soldering, 10 sec) 300°C
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.
THERMAL RESISTANCE
θJA is specified for the worst-case conditions, that is, a device
soldered in a circuit board for surface-mount packages.
2 RFB Internal Matching Feedback Resistor. Connect to external op amp output.
3 I
DAC Current Output, full-scale output 1 LSB less than reference input voltage −V
OUT
REF
.
4 GND Analog and Digital Ground.
5
LD Load Strobe, Level-Sensitive Digital Input. Transfers shift-register data to DAC register while active low.
Table 3 for operation.
See
6 SRI 12-Bit Serial Register Input. Data loads directly into the shift register MSB first. Extra leading bits are ignored.
7 CLK Clock Input. Positive-edge clocks data into shift register.
8 VDD Positive Power Supply Input. Specified range of operation 5 V ± 10%.
Rev. 0 | Page 6 of 16
AD5441
TYPICAL PERFORMANCE CHARACTERISTICS
0.5
TA=25°C
V
= 10V
REF
0.4
V
=3V
DD
0.3
0.2
0.1
0
INL (LSB)
–0.1
–0.2
–0.3
–0.4
–0.5
05001000 1500 2000 2500 3000 3500 4000
CODE
Figure 5. INL vs. Code, 3 V
0.5
TA= 25°C
=10V
V
0.4
REF
=3V
V
DD
0.3
0.2
0.1
0
DNL (LSB)
–0.1
–0.2
–0.3
–0.4
–0.5
05001000 1500 2000 2500 3000 3500 4000
CODE
Figure 6. DNL vs. Code, 3 V
0.25
MAX INL
0.20
0.15
0.10
0.05
0
INL (LSB)
–0.05
–0.10
–0.15
–0.20
MIN INL
012510
37648
REFERENCE VOL TAGE
Figure 7. INL vs. Reference, 5 V
06492-039
06492-037
TA= 25°C
V
= 5V
DD
06492-042
9
0.5
TA=25°C
= 10V
V
REF
0.4
= 5V
V
DD
0.3
0.2
0.1
0
INL (LSB)
–0.1
–0.2
–0.3
–0.4
–0.5
05001000 1500 2000 2500 3000 3500 4000
CODE
Figure 8. INL vs. Code, 5 V
0.5
TA= 25°C
= 10V
V
0.4
REF
= 5V
V
DD
0.3
0.2
0.1
0
DNL (LSB)
–0.1
–0.2
–0.3
–0.4
–0.5
05001000 1500 2000 2500 3000 3500 4000
CODE
Figure 9. DNL vs. Code, 5 V
100
75
50
FREQUENCY
25
0
–1.0–0. 500.51.0
TOTAL UNADJUST ED ERROR (LSB)
Figure 10. Total Unadjusted Error Histogram
06492-040
06492-038
06492-048
Rev. 0 | Page 7 of 16
AD5441
4
2
0
INL (LSB)
–2
–4
–2000–1000010002000
OP AMP OFFSET, VOS (µV)
Figure 11. Integral Nonlinearity Error vs. External Op Amp
1400
= 25°C
T
A
V
REF
V
DD
OP42
= 10V
= 5V
0.050
TA = 25°C
0.045
0.040
0.035
0.030
0.025
0.020
CURRENT (µA)
0.015
0.010
0.005
0
–60 –40
06492-049
VDD = 3V
VDD = 5V
–20
0 20406080100120
TEMPERATURE ( °C)
06492-044
Figure 14. Supply Current vs. Temperature
50
1200
1000
800
600
CURRENT (µA)
400
200
0
10k100k1M10M100M
FREQUENCY (Hz)
Figure 12. Supply Current vs. Clock Frequency
0.20
TA = 25°C
0.18
0.16
0.14
0.12
0.10
0.08
CURRENT (µA)
0.06
0.04
0.02
0
00. 5 1.0 1.5 2.0 2.5 3.0 3.5 4. 0 4.5 5.0
INPUT VOLTAGE (V)
Figure 13. Supply Current vs. Logic Input Voltage
F55
FFF
800
40
30
20
FREQUENCY
10
06492-035
0
0123
FULL-SCAL E TEMPERATURE COEFFI CIENT (ppm/°C)
06492-046
Figure 15. Full-Scale Output Temperature Coefficient Histogram
5.34
5.32
5.30
5.28
5.26
5.24
5.22
5.20
OUTPUT VO LTAGE (V )
5.18
5.16
06492-043
5.14
5.12
–0.200.20.40.60.81.01.21.4
LDAC
TIME (µs)
TA = 25°C
V
= 10V
REF
V
= 5V
DD
7FF TO 800
RISING EDGE
6
5
4
3
2
1
0
–1
–2
–3
–4
–5
–6
–7
–8
–9
–10
(V)
LOAD
V
06492-033
Figure 16. Midscale Transitions
Rev. 0 | Page 8 of 16
AD5441
–20
–32
4
–8
ALL BITS
ON
100
TA = 25°C
V
= 10V
REF
V
= 5V
80
60
DD
–44
ATTENUATIO N (dB)
–56
–68
–80
1001k10k100k1M10M
FREQUENCY (Hz)
TA = 25°C
V
= 100mV rms
REF
V
= 5V
DD
Figure 17. Reference Multiplying Bandwidth
06492-045
PSRR (dB)
40
20
0
1k10k100k1M10M
FREQUENCY (Hz)
Figure 18. PSRR vs. Frequency
06492-027
Rev. 0 | Page 9 of 16
AD5441
TERMINOLOGY
Relative Accuracy (INL)
Relative accuracy or endpoint nonlinearity is a measure of the
maximum deviation from a straight line passing through the
endpoints of the DAC transfer function. It is measured after
adjusting for zero and full scale and is normally expressed in
LSBs or as a percentage of the full-scale reading.
Differential Nonlinearity (DNL)
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 over the operating
temperature range ensures monotonicity.
Gain Error
Gain error or full-scale error is a measure of the output error
between an ideal DAC and the actual device output. For these
DACs, ideal maximum output is V
DACs is adjustable to zero with external resistance.
Zero Scale Error
Calculated from worst-case R
I
(LSB) = (R
ZSE
REF
× I
× 4096)/V
LKG
Output Leakage Current
Output leakage current is the current that flows into the DAC
ladder switches when they are turned off. For the I
it can be measured by loading all 0s to the DAC and measuring
the I
current.
OUT
Output Capacitance
Capacitance from I
1 to AGND.
OUT
Digital-to-Analog Glitch Impulse
The amount of charge injected from the digital inputs to the
analog output when the inputs change state. This is normally
specified as the area of the glitch in either pA-s or nV-s,
depending on whether the glitch is measured as a current or
voltage signal.
− 1 LSB. Gain error of the
REF
REF
.
REF
terminal,
OUT
Digital Feedthrough
When the device is not selected, high frequency logic activity
on the digital inputs of the device may be capacitively coupled
through the device and produce noise on the I
pins. This
OUT
noise is coupled from the outputs of the device onto follow-on
circuitry. This noise is digital feedthrough.
Multiplying Feedthrough Error
This is the error due to capacitive feedthrough from the DAC
reference input to the DAC I
1 terminal when all 0s are
OUT
loaded to the DAC.
Total Harmonic Distortion (THD)
The DAC is driven by an ac reference. The ratio of the rms sum
of the harmonics of the DAC output to the fundamental value is
the THD. Usually only the lower order harmonics, such as
second to fifth, are included.
2222
V5V4V3V2
THD
log20
=
V1
+++
Compliance Voltage Range
The maximum range of (output) terminal voltage for which the
device provides the specified characteristics.
Output Noise Spectral Density
Calculation from
= √4KTRB
e
n
where:
K is Boltzmann Constant (J/°K).
R is resistance ().
T is the resistor temperature (°K).
B is the 1 Hz bandwidth.
Rev. 0 | Page 10 of 16
AD5441
Ω
Ω
V
V
V
2
PARAMETER DEFINITIONS
GENERAL CIRCUIT INFORMATION
The AD5441 is a 12-bit multiplying DAC with a low
temperature coefficient. It contains an R-2R resistor ladder
network, data input and control logic, and two data registers.
The digital circuitry forms an interface in which serial data can
be loaded under microprocessor control into a 12-bit shift register
and then transferred, in parallel, to the 12-bit DAC register.
The analog portion of the AD5441 contains an inverted R-2R
ladder network consisting of silicon-chrome, highly stable
(50 ppm/°C), thin-film resistors, and 12 pairs of NMOS currentsteering switches, see
weighted currents into either I
current in each ladder leg, regardless of digital input code. This
constant current results in a constant input resistance at V
equal to R. The V
or current, ac or dc, that is within the limits stated in the
Absolute Maximum Ratings.
REF
*THESE SWI TCHES PERMANENTLY ON.
NOTES
1. SWIT CHES SHOWN F OR DIGITAL INPUT S HIGH.
10kΩ
20kΩS220kΩ
S1
BIT 1 (MSB) BIT 2BIT 3 BIT 12 (LSB)
The 12 output current steering NMOS FET switches are in
series with each R-2R resistor.
To further ensure accuracy across the full temperature range,
MOS switches that are always on were included in series with
the feedback resistor and the terminating resistor of the R-2R
ladder.
Figure 19 shows the location of the series switches.
Figure 19. These switches steer binarily
or GND; this yields a constant
OUT
input may be driven by any reference voltage
REF
10k
DIGITAL INPUTS
Figure 19. Simplified DAC Circuit
20kΩ
S3
10k
20kΩ
S12
20kΩ
*
10kΩ
*
REF
GND
I
OUT
R
FEEDBACK
During any testing of the resistor ladder or R
incoming inspection), V
must be present to turn on these
DD
series switches.
OUTPUT IMPEDANCE
The output resistance of the AD5441, as in the case of the
output capacitance, varies with the digital input code. This
resistance, looking back into the I
terminal, may be between
OUT
10 kΩ (the feedback resistor alone when all digital inputs are
low) and 7.5 kΩ (the feedback resistor in parallel with approximate
30 kΩ of the R-2R ladder network resistance when any single bit
logic is high). Static accuracy and dynamic performance are
affected by these variations.
APPLICATIONS INFORMATION
In most applications, linearity depends upon the potential of
and GND pins being at the same voltage potential. The
the I
OUT
DAC is connected to an external precision op amp inverting input.
The external amplifiers noninverting input should be tied directly
to ground without the usual bias current compensating resistor (see
Figure 20 and Figure 22). The selected amplifier should have a low
input bias current and low drift over temperature. The amplifiers
input offset voltage should be nulled to less than 200 mV (less than
10% of 1 LSB). All grounded pins should tie to a single common
ground point to avoid ground loops. The V
power supply should
DD
have a low noise level with adequate bypassing. It is best to operate
the AD5441 from the analog power supply and grounds.
UNIPOLAR 2-QUADRANT MULTIPLYING
The most straightforward application of the AD5441 is in the
06492-021
2-quadrant multiplying configuration shown in
reference input signal is replaced with a fixed dc voltage reference,
the DAC output provides a proportional dc voltage output
according to the transfer equation
= −D/4096 × V
V
OUT
REF
where:
D is the decimal data loaded into the DAC register.
V
is the externally applied reference voltage source.
REF
(such as
FEEDBACK
Figure 20. If the
DD
V
DD
R1
V
REF
AD5441
CLK SRI
LD
µCONTROLLER
REF
NOTES
1. R1 AND R2 USED ONLY IF GAIN ADJUS TMENT I S REQUIRED.
. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED
IF A1 IS A HIGH SPEED AMPLIFIER.
R2
R
FB
I
OUT
GND
C1
1
AGND
A1
V
= 0 TO –V
OUT
REF
06492-023
Figure 20. Unipolar (2-Quadrant) Operation
Rev. 0 | Page 11 of 16
AD5441
V
BIPOLAR 4-QUADRANT MULTIPLYING
Figure 22 shows a suggested circuit to achieve 4-quadrant
multiplying operation. The summing amplifier multiplies V
by 2 and offsets the output with the reference voltage so that a
midscale digital input code of 2048 places V
full-scale voltage is V
The positive full-scale output is −(V
when the DAC is loaded with all zeros.
REF
− 1 LSB) when the DAC
REF
at 0 V. The negative
OUT2
is loaded with all ones. Therefore, the digital coding is offset
binary. The voltage output transfer equation for various input
data and reference (or signal) values follows
= (D/2048 − 1) − V
V
OUT2
REF
where:
D is the decimal data loaded into the DAC register.
V
is the externally applied reference voltage source.
REF
INTERFACE LOGIC INFORMATION
The AD5441 has been designed for ease of operation. The
timing diagram in
sequence. Note that the most significant bit (MSB) is loaded
first. Once the 12-bit input register is full, the data is transferred
to the DAC register by taking
Figure 2 illustrates the input register loading
LD
momentarily low.
V
DD
V
DD
V
REF
±10V
NOTES
1. R1 AND R2 ARE USED ONLY IF GAI N ADJUSTMENT I S REQUIRED.
ADJUST R1 FOR V
2. MATCHING AND TRACKING IS E SSENTIAL FOR RESI STOR PAIRS
R3 AND R4.
3. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED
IF A1/A2 IS A HIGH SPEED AMPLIFIER.
R1
V
REF
AD5441
CLK S RILD
µCONTROLLER
= 0V WITH CODE 10000000 LOADED TO DAC.
OUT
Figure 22. Bipolar (4-Quadrant) Operation
OUT1
R3
20kΩ
R2
R
FB
I
1
OUT
GND
AGND
DIGITAL SECTION
The digital inputs of the AD5441, SRI, LD, and CLK, are TTLcompatible. The input voltage levels affect the amount of current
drawn from the supply; peak supply current occurs as the digital
input (V
for the supply current vs. logic input voltage graph. Maintaining
the digital input voltage levels as close as possible to the supplies,
V
DD
digital inputs of the AD5441 were designed with ESD resistance
incorporated through careful layout and the inclusion of input
protection circuitry.
and series resistor; this input structure is duplicated on each
digital input. High voltage static charges applied to the inputs
are shunted to the supply and ground rails through forwardbiased diodes. These protection diodes were designed to clamp
the inputs to well below dangerous levels during static discharge
conditions.
C1
A1
) passes through the transition region. See Figure 13
IN
and GND, minimizes supply current consumption. The
Figure 21 shows the input protection diodes
DD
LD, CLK, SRI
R4
10kΩ
GND
Figure 21. Digital Input Protection
R5
20kΩ
A2
5kΩ
= –V
V
OUT
REF
TO +V
REF
06492-024
06492-020
Rev. 0 | Page 12 of 16
AD5441
OUTLINE DIMENSIONS
3.25
3.00 SQ
2.75
2.95
INDICATOR
0.90 MAX
0.85 NOM
SEATING
PLANE
PIN 1
12° MAX
TOP
VIEW
0.70 MAX
0.65 TYP
0.30
0.23
0.18
2.75 SQ
2.55
0.05 MAX
0.01 NOM
0.20 REF
Figure 23. 8-Lead Lead Frame Chip Scale Package [LFCSP_VD]
3 mm × 3 mm Body, Very Thin, Dual Lead
Dimensions are shown in millimeters
3.20
3.00
2.80
0.60 MAX
0.50
0.40
0.30
(CP-8-2)
0.60 MAX
5
EXPOSED
PA D
(BOTTO M VIEW)
4
0.50
BSC
8
1.60
1.45
1.30
1
1.89
1.74
1.59
PIN 1
INDICATOR
61507-B
8
5
4
SEATING
PLANE
5.15
4.90
4.65
1.10 MAX
0.23
0.08
8°
0°
0.80
0.60
0.40
3.20
3.00
1
2.80
PIN 1
0.65 BSC
0.95
0.85
0.75
0.15
0.38
0.00
0.22
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 24. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions are shown in millimeters
ORDERING GUIDE
Model INL (LSB) Temperature Range Package Description Package Option Branding