DAC7741
DAC
774
1
SBAS248B – DECEMBER 2001 – REVISED AUGUST 2007
16-Bit, Single Channel
DIGITAL-TO-ANALOG CONVERTER
With Internal Reference and Parallel Interface
FEATURES
DESCRIPTION
● LOW POWER: 150mW MAXIMUM
● +10V INTERNAL REFERENCE
● UNIPOLAR OR BIPOLAR OPERATION
● SETTLING TIME: 5µs to ±0.003% FSR
● 16-BIT MONOTONICITY, –40°C TO +85°C
● ±10V, ±5V OR +10V CONFIGURABLE VOLTAGE
OUTPUT
● RESET TO MIN-SCALE OR MID-SCALE
● DOUBLE-BUFFERED DATA INPUT
● INPUT REGISTER DATA READBACK
● SMALL LQFP-48 PACKAGE
The DAC7741 is a 16-bit Digital-to-Analog Converter (DAC)
which provides 16 bits of monotonic performance over the
specified operating temperature range and offers a +10V,
low-drift internal reference. Designed for automatic test equipment and industrial process control applications, the DAC7741
output swing can be configured in a ±10V, ±5V, or +10V
range. The flexibility of the output configuration allows the
DAC7741 to provide both unipolar and bipolar operation by
pin strapping. The DAC7741 includes a high-speed output
amplifier with a maximum settling time of 5µs to ±0.003%
FSR for a 20V full-scale change and only consumes 100mW
(typical) of power.
The DAC7741 features a standard 16-bit parallel interface with
double buffering to allow asynchronous updates of the analog
output and data read-back to support data integrity verification
prior to an update. A user-programmable reset control allows
the DAC output to reset to min-scale (0000H) or mid-scale
(8000H) overriding the DAC register values. The DAC7741 is
available in a LQFP-48 package and four performance grades
specified to operate from 0°C to +70°C and –40°C to +85°C.
APPLICATIONS
● PROCESS CONTROL
● ATE PIN ELECTRONICS
● CLOSED-LOOP SERVO CONTROL
● MOTOR CONTROL
● DATA ACQUISITION SYSTEMS
VDD VSS VCC
REFADJ
REFOUT REFIN
VREF
ROFFSET
Buffer
REFEN
RFB2
+10V
Reference
CS
R/W
Control
Logic
RST
RFB1
RSTSEL
SJ
Data I/O
16
I/O
Buffer
AGND
Input
Register
DGND
DAC
Register
DAC
VOUT
LDAC
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
Copyright © 2001-2007, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
www.ti.com
ELECTROSTATIC
DISCHARGE SENSITIVITY
ABSOLUTE MAXIMUM RATINGS(1)
VCC to VSS ........................................................................... –0.3V to +34V
VCC to AGND ...................................................................... –0.3V to +17V
VSS to AGND ...................................................................... –17V to +0.3V
AGND to DGND ................................................................. –0.3V to +0.3V
REFIN to AGND ............................................................. 0V to VCC – 1.4V
VDD to DGND ........................................................................ –0.3V to +6V
Digital Input Voltage to DGND ................................. –0.3V to VDD + 0.3V
Digital Output Voltage to DGND .............................. –0.3V to VDD + 0.3V
Operating Temperature Range ........................................ –40°C to +85°C
Storage Temperature Range ......................................... –65°C to +150°C
Junction Temperature .................................................................... +150°C
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may be
more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.
NOTE: (1) Stresses above those listed under Absolute Maximum Ratings may
cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.
PACKAGE/ORDERING INFORMATION
PRODUCT
LINEARITY
ERROR
(LSB)
DIFFERENTIAL
NONLINEARITY
(LSB)
PACKAGE-LEAD
PACKAGE
DESIGNATOR(1)
SPECIFIED
TEMPERATURE
RANGE
DAC7741Y
±6
"
±4
LQFP-48
PT
–40°C to +85°C
"
"
"
"
±4
±2
LQFP-48
PT
–40°C to +85°C
"
"
"
"
"
±3
±1
LQFP-48
PT
–40°C to +85°C
"
"
"
"
"
±2
±1
LQFP-48
PT
0°C to +70°C
"
"
"
"
"
"
DAC7741YB
"
DAC7741YC
"
DAC7741YL
"
ORDERING
NUMBER
PACKAGE
MARKING
TRANSPORT
MEDIA, QUANTITY
DAC7741Y/250
DAC7741Y/2K
DAC7741Y
Tape and Reel, 250
Tape and Reel, 2000
DAC7741YB/250
DAC7741YB/2K
DAC7741YB
DAC7741YC/250
DAC7741YC/2K
DAC7741YC
DAC7741YL/250
DAC7741YL/2K
DAC7741YL
"
"
"
"
Tape and Reel, 250
Tape and Reel, 2000
Tape and Reel, 250
Tape and Reel, 2000
Tape and Reel, 250
Tape and Reel, 2000
NOTE: (1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI web site at www.ti.com.
ELECTRICAL CHARACTERISTICS
All specifications at TA = TMIN to TMAX, VCC = +15V, VSS = –15V, VDD = +5V, internal reference enabled, unless otherwise noted.
DAC7741Y
PARAMETER
CONDITIONS
MIN
TYP
ACCURACY
Linearity Error (INL)
Gain Error Drift
PSRR (VCC or VSS)
ANALOG OUTPUT(1)
Voltage Output(2)
Output Current
Output Impedance
Maximum Load Capacitance
Short-Circuit Current
Short-Circuit Duration
14
REFIN Input Current
REFADJ Input Range
With Internal REF
With External REF
With Internal REF
At Full-Scale
±15
50
+11.4/–4.75(1)
+11.4/–11.4(1)
+11.4/–6.4(1)
0 to 10
±10
±5
±5
REFADJ Input Impedance
VREF Output Current
VREF Impedance
2
±0.1
9.96
±25
4.75
MAX
UNITS
±4
±3
±2
LSB
LSB
LSB
Bits
% of FSR
ppm/°C
% of FSR
% of FSR
ppm/°C
ppm/V
✻
✻
±0.4
±0.25
±10
✻
200
±0.25
±0.1
✻
✻
✻
✻
V
V
V
mA
Ω
pF
mA
✻
✻
✻
✻
✻
0.1
200
±15
Indefinite
AGND
10
400
±15
10.04
9.975
VCC – 1.4
✻
✻
10
✻
0
+2
✻
1
10.025
✻
V
Ω
ppm/°C
mV
V
✻
nA
V
✻
50
–2
✻
✻
±10
✻
10
Absolute Max Value that
can be applied is VCC
TYP
15
±2
REFERENCE
Reference Output
REFOUT Impedance
REFOUT Voltage Drift
REFOUT Voltage Adjustment(3)
REFIN Input Range(4)
MIN
±6
±5
±4
TA = 25°C
Differential Linearity Error (DNL)
Monotonicity
Offset Error
Offset Error Drift
Gain Error
DAC7741YB
MAX
✻
✻
kΩ
mA
Ω
DAC7741
www.ti.com
SBAS248B
ELECTRICAL CHARACTERISTICS (Cont.)
All specifications at TA = TMIN to TMAX, VCC = +15V, VSS = –15V, VDD = +5V, internal reference enabled, unless otherwise noted.
DAC7741Y
PARAMETER
DYNAMIC PERFORMANCE
Settling Time to ±0.003%
Digital Feedthrough
Output Noise Voltage
DIGITAL INPUT
VIH
VIL
DIGITAL OUTPUT
VOH
VOL
POWER SUPPLY
VDD
VCC
VSS
IDD
ICC
ISS
Power
TEMPERATURE RANGE
Specified Performance
CONDITIONS
MIN
20V Output Step
RL = 5kΩ, CL = 200pF,
with external REFOUT
to REFIN filter(5)
|IH| < 10µA
|IL| < 10µA
0.7 • VDD
IOH = –0.8mA
IOL = 1.6mA
3.6
Unloaded
Unloaded
No Load, Ext. Reference
No Load, Int. Reference
MAX
3
5
MIN
TYP
MAX
UNITS
✻
✻
µs
✻
✻
2
100
at 10kHz
Bipolar Operation
Unipolar Operation
DAC7741YB
TYP
✻
0.3 • VDD
–4
–40
✻
V
V
✻
V
V
✻
0.4
+4.75
+11.4
–15.75
–15.75
nV-s
nV/√Hz
+5.0
100
4
–2.5
85
100
+5.25
+15.75
–11.4
–4.75
✻
✻
✻
✻
6
✻
150
+85
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
V
V
V
V
µA
mA
mA
mW
mW
✻
°C
✻
✻ Specifications same as grade to the left.
NOTES: (1) With minimum VCC /VSS requirements, internal reference enabled.
(2) Please refer to the “Theory of Operation” section for more information with respect to output voltage configurations.
(3) See Figure 7 for gain and offset adjustment connection diagrams when using the internal reference.
(4) The minimum value for REFIN must be equal to the greater of VSS +14V and +4.75V, where +4.75V is the minimum voltage allowed.
(5) Reference low-pass filter values: 100kΩ, 1.0µF (See Figure 10).
DAC7741
SBAS248B
www.ti.com
3
ELECTRICAL CHARACTERISTICS
All specifications at TA = TMIN to TMAX, VCC = +15V, VSS = –15V, VDD = +5V, internal reference enabled, unless otherwise noted.
DAC7741YL
PARAMETER
CONDITIONS
MIN
TYP
ACCURACY
Linearity Error (INL)
±1
TA = 25°C
Differential Linearity Error (DNL)
Monotonicity
Offset Error
Offset Error Drift
Gain Error
Gain Error Drift
PSRR (VCC or VSS)
ANALOG OUTPUT(1)
Voltage Output(2)
Output Current
Output Impedance
Maximum Load Capacitance
Short-Circuit Current
Short-Circuit Duration
With Internal REF
With External REF
With Internal REF
At Full-Scale
±15
50
+11.4/–4.75(1)
+11.4/–11.4(1)
+11.4/–6.4(1)
0 to 10
±10
±5
±5
Digital Feedthrough
Output Noise Voltage
DIGITAL INPUT
VIH
VIL
DIGITAL OUTPUT
VOH
VOL
POWER SUPPLY
VDD
VCC
VSS
IDD
ICC
ISS
Power
TEMPERATURE RANGE
Specified Performance
MIN
±2
±1
±0.1
9.96
±25
4.75
10
400
±15
±0.4
±0.25
3
IOH = –0.8mA
IOL = 1.6mA
3.6
Bipolar Operation
Unipolar Operation
Unloaded
Unloaded
No Load, Ext. Reference
No Load, Int. Reference
V
V
V
mA
Ω
pF
mA
✻
✻
✻
✻
10.04
9.975
VCC – 1.4
✻
✻
10
✻
+2
✻
✻
✻
±7
10.025
0
nA
V
✻
kΩ
mA
Ω
✻
µs
✻
✻
5
✻
✻
nV-s
nV/√Hz
✻
✻
V
V
✻
V
V
✻
0.4
–4
✻
✻
0.3 • VDD
+4.00
+11.4
–15.75
–15.75
✻
V
Ω
ppm/°C
mV
V
✻
2
100
0.7 • VDD
✻
✻
✻
✻
1
|IH| < 10µA
|IL| < 10µA
LSB
LSB
LSB
Bits
% of FSR
ppm/°C
% of FSR
% of FSR
ppm/°C
ppm/V
±0.2
±0.1
±7
✻
200
50
–2
at 10kHz
±3
±2
±1
✻
0
20V Output Step
RL = 5kΩ, CL = 200pF,
with external REFOUT
to REFIN filter(5)
UNITS
✻
10
Absolute Max Value that
can be applied is VCC
MAX
✻
0.1
200
±15
Indefinite
AGND
TYP
16
±2
REFADJ Input Impedance
VREF Output Current
VREF Impedance
DYNAMIC PERFORMANCE
Settling Time to ±0.003%
MAX
16
REFERENCE
Reference Output
REFOUT Impedance
REFOUT Voltage Drift
REFOUT Voltage Adjustment(3)
REFIN Input Range(4)
REFIN Input Current
REFADJ Input Range
DAC7741YC
+5.0
100
4
–2.5
85
100
+5.25
+15.75
–11.4
–4.75
+4.75
✻
✻
✻
6
✻
150
70
✻
✻
✻
✻
✻
✻
–40
✻
✻
✻
✻
✻
V
V
V
V
µA
mA
mA
mW
mW
+85
°C
✻
✻ Specifications same as grade to the left.
NOTES: (1) With minimum VCC / VSS requirements, internal reference enabled.
(2) Please refer to the “Theory of Operation” section for more information with respect to output voltage configurations.
(3) See Figure 7 for gain and offset adjustment connection diagrams when using the internal reference.
(4) The minimum value for REFIN must be equal to the greater of VSS +14V and +4.75V, where +4.75V is the minimum voltage allowed.
(5) Reference low-pass filter values: 100kΩ, 1.0µF (See Figure 10).
4
DAC7741
www.ti.com
SBAS248B
PIN CONFIGURATION
REFIN
REFADJ
REFOUT
REFEN
RSTSEL
R/W
CS
LDAC
RST
VDD
DGND
LQFP
NC
Top View
48
47
46
45
44
43
42
41
40
39
38
37
NC
1
36 NC
VSS
2
35 DB15
VCC
3
34 DB14
VREF
4
33 DB13
ROFFSET
5
32 DB12
AGND
6
AGND
7
30 DB10
RFB2
8
29 DB9
RFB1
9
28 DB8
SJ 10
27 DB7
31 DB11
DAC7741
VOUT 11
26 TEST
NC
DB0
DB1
DB2
19
20
21
22
23
24
NC
18
NC
17
DB6
16
DB5
15
DB4
14
DB3
13
NC
25 NC
NC
NC 12
PIN DESCRIPTIONS
PIN
NAME
DESCRIPTION
PIN
NAME
DB8
DESCRIPTION
1
NC
No Connection
28
Data Bit 8
2
VSS
Negative Analog Power Supply.
29
DB9
Data Bit 9
3
VCC
Positive Analog Power Supply.
30
DB10
Data Bit 10
4
VREF
Buffered Output from REFIN, can be used to
drive external devices. Internally, this pin
directly drives the DAC circuitry.
31
DB11
Data Bit 11
32
DB12
Data Bit 12
33
DB13
Data Bit 13
Offsetting Resistor
34
DB14
Data Bit 14
DB15
Data Bit 15 (MSB)
5
ROFFSET
6
AGND
Analog ground (Must be tied to analog ground)
35
7
AGND
Analog ground (Must be tied to analog ground)
36
NC
No Connection
8
RFB2
Feedback Resistor 2, used to configure DAC
output range.
37
DGND
Digital Ground
38
VDD
Digital Power Supply
Feedback Resistor 1, used to configure DAC
output range.
39
RST
VOUT reset; active LOW, depending on the state of
RSTSEL, the DAC register is either reset to midscale or min-scale.
40
LDAC
9
RFB1
10
SJ
11
VOUT
Summing Junction of the Output Amplifier
12
NC
No Connection
13
NC
No Connection
14
NC
No Connection
41
CS
Chip Select, active LOW
42
R/W
Enabled by CS, controls data read (HIGH) and
write (LOW) from or to the input register.
43
RSTSEL
Reset Select; determines the action of RST. If
HIGH, RST will reset the DAC register to midscale. If LOW, RST will reset the DAC register to
min-scale.
44
REFEN
Enables internal +10V reference (REFOUT), active
LOW.
DAC Voltage Output
DAC register load control, rising edge triggered.
Data is loaded from the input register to the DAC
register.
15
NC
No Connection
16
DB0
Data Bit 0 (LSB)
17
DB1
Data Bit 1
18
DB2
Data Bit 2
19
DB3
Data Bit 3
20
DB4
Data Bit 4
21
DB5
Data Bit 5
22
DB6
Data Bit 6
45
REFOUT
Internal Reference Output
46
REFADJ
Internal Reference Trim. (Acts as a gain
adjustment input when the internal reference is
used.)
47
REFIN
Reference Input
48
NC
No Connection
23
NC
No Connection
24
NC
No Connection
25
NC
26
TEST
27
DB7
No Connection
Reserved, Connect to DGND
Data Bit 7
DAC7741
SBAS248B
www.ti.com
5
TIMING CHARACTERISTICS
DAC7741Y
PARAMETER
tRCS
tRDS
tRDH
tDZ
tCSD
tWCS
tWS
tWH
tLS
tLH
tLX
tDS
tDH
tLWD
tSS
tSH
tRSS
tS
DESCRIPTION
MIN
CS LOW for Read
R/W HIGH to CS LOW
R/W HIGH after CS HIGH
CS HIGH to Data Bus High Impedance
CS LOW to Data Bus Valid
CS LOW for Write
R/W LOW to CS LOW
R/W LOW after CS HIGH
CS LOW to LDAC HIGH
CS LOW after LDAC HIGH
LDAC HIGH
Data Valid to CS LOW
Data Valid after CS HIGH
LDAC LOW
RSTSEL Valid Before RST LOW
RSTSEL Valid After RST HIGH
RST LOW
Voltage Output Settling Time
100
10
10
10
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
µs
70
100
85
30
10
10
40
0
30
0
20
40
0
10
30
5
TIMING DIAGRAMS
tWCS
CS
tWS
tWH
R/W
Data In
DB15-DB0
LDAC
tRCS
CS
tRDS
tDH
Data Valid
tDS
tLS
tLWD
tRDH
R/W
tLH
Data Out
DB15-DB0
tLX
Data Valid
tDZ
tCSD
tS
VOUT
READ CYCLE
±0.003% of FSR
Error Bands
WRITE CYCLE
RESET TIMING
tSS
RSTSEL
tSH
tRSS
RST
tS
+FS
VOUT
(RSTSEL = LOW)
Min-Scale
–FS
+FS
VOUT
Mid-Scale
(RSTSEL = HIGH)
–FS
6
DAC7741
www.ti.com
SBAS248B
TYPICAL CHARACTERISTICS
6
4
2
0
–2
–4
–6
INL (LSB)
6
4
2
0
–2
–4
–6
LINEARITY ERROR AND DIFFERENTIAL
LINEARITY ERROR vs DIGITAL INPUT CODE
Bipolar Configuration: VOUT = –10V to +10V
TA = 85°C, Internal Reference Enabled
2.0
1.5
1.0
0.5
0.0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
DNL (LSB)
DNL (LSB)
INL (LSB)
TA = +25°C (unless otherwise noted)
LINEARITY ERROR AND DIFFERENTIAL
LINEARITY ERROR vs DIGITAL INPUT CODE
Bipolar Configuration: VOUT = –10V to +10V
TA = 25°C, Internal Reference Enabled
2.0
1.5
1.0
0.5
0.0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
6
4
2
0
–2
–4
–6
Digital Input Code
LINEARITY ERROR AND DIFFERENTIAL
LINEARITY ERROR vs DIGITAL INPUT CODE
5
3
2
Bipolar Configuration: VOUT = –10V to +10V
TA = –40°C, Internal Reference Enabled
2.0
1.5
1.0
0.5
0.0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
0
–1
–3
–4
–5
–40
4.4
10
35
60
85
Ext. Ref, Unipolar Mode:
VOUT = 0 to +10V
VCC SUPPLY CURRENT vs DIGITAL INPUT CODE
Bipolar Configuration: VOUT = –10V to +10V
Internal Reference Enabled, TA = 25°C
4.2
ICC (mA)
Error (%)
0.025
4.3
Int. Ref, Bipolar Mode:
VOUT = –10 to +10V
0.075
–15
Temperature (°C)
Int. Ref, Unipolar Mode: VOUT = 0 to +10V
0.100
VOUT = 0 to +10V
–2
GAIN ERROR vs TEMPERATURE
0.125
VOUT = –10 to +10V
1
Digital Input Code
0.050
OFFSET ERROR vs TEMPERATURE
4
Error (mV)
DNL (LSB)
INL (LSB)
Digital Input Code
4.1
4.0
3.9
0.000
3.8
Ext. Ref, Bipolar Mode:
VOUT = –10 to +10V
–0.025
–40
–15
10
35
60
3.7
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
85
Temperature (°C)
Digital Input Code
DAC7741
SBAS248B
www.ti.com
7
TYPICAL CHARACTERISTICS (Cont.)
TA = +25°C (unless otherwise noted)
VCC SUPPLY CURRENT vs DIGITAL INPUT CODE
3.4
3.3
VSS SUPPLY CURRENT vs DIGITAL INPUT CODE
–1.50
Bipolar Configuration: VOUT = –10V to +10V
External Reference, REFEN = 5V, TA = 25°C
–1.75
3.1
ISS (mA)
ICC (mA)
3.2
3.0
–2.00
–2.25
2.9
–2.50
Bipolar Configuration: VOUT = –10V to +10V
TA = 25°C
2.8
–2.75
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
2.7
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
SUPPLY CURRENT vs TEMPERATURE
6
SUPPLY CURRENT vs LOGIC INPUT VOLTAGE
1000
TA = 25°C, Transition
Shown for One Data
Input (CS = 5V, R/W = 0)
5
800
4
ICC
2
IDD (µA)
ICC, ISS (mA)
3
Load Current Excluded, VCC = +15V, VSS = –15V
Bipolar VOUT Configuration: –10V to +10V
1
0
600
400
–1
ISS
–2
200
–3
0
–4
–40
–15
10
35
60
0.0
85
0.5
1.0
1.5
90
HISTOGRAM OF VCC CURRENT CONSUMPTION
Bipolar Output Configuration
Internal Reference Enabled
Code = 5555H
90
80
70
70
60
60
50
40
20
20
10
10
0
0
4.000
4.500
5.000
4.5
5.0
Bipolar Output Configuration
Internal Reference Enabled
Code = 5555H
–3.50
–3.00
–2.50
–2.00
–1.50
ISS (mA)
ICC (mA)
8
4.0
40
30
3.500
3.5
50
30
3.000
3.0
HISTOGRAM OF VSS CURRENT CONSUMPTION
100
Frequency
Frequency
80
2.5
VLOGIC (V)
Temperature (°C)
100
2.0
DAC7741
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TYPICAL CHARACTERISTICS (Cont.)
TA = +25°C (unless otherwise noted)
POWER SUPPY REJECTION RATIO vs FREQUENCY
(Measured at VOUT)
10
–20
–10
–20
–30
–40
VSS
–50
VCC
–60
Bipolar Configuration: ±10V VOUT, Code FFFFH
–VSS, VCC = 15V + 1Vp-p, VDD = 5V + 0.5Vp-p
0
PSRR (dB)
–10
PSRR (dB)
10
Bipolar Configuration: ±10V VOUT
Code 8000H
–VSS, VCC = 15V + 1Vp-p
VDD = 5V + 0.5Vp-p
0
POWER SUPPY REJECTION RATIO vs FREQUENCY
(Measured at VOUT)
VSS
–30
VCC
–40
–50
VDD
–60
–70
–70
–80
0.1K
VDD
1K
10K
100K
1M
–80
0.01K
10M
0.1K
1K
Frequency (Hz)
15V
10.010
0V
10.005
10V
1M
10M
INTERNAL REFERENCE OUTPUT vs TEMPERATURE
10.015
REFOUT (V)
REFOUT (2V/div)
VCC (5V/div)
INTERNAL REFERENCE START-UP
10K
100K
Frequency (Hz)
10.000
9.995
9.990
0V
9.985
–40
Time (2ms/div)
–15
10
35
60
85
Temperature (°C)
OUTPUT VOLTAGE vs RLOAD
12
REFOUT VOLTAGE vs LOAD
11.0
Source
Loaded to VCC
8
REFOUT (V)
4
VOUT (V)
VCC = +15V
10.5
0
10.0
9.5
–4
Sink
9.0
–8
Loaded to AGND
8.5
–12
0.0
0.1
1.0
10.0
100.0
10
100
1K
REFOUT LOAD(kΩ)
RLOAD (kΩ)
DAC7741
SBAS248B
1
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9
TYPICAL CHARACTERISTICS (Cont.)
TA = +25°C (unless otherwise noted)
POWER-SUPPY REJECTION RATIO vs FREQUENCY
(Measured at REFOUT)
10
–10
–20
VCC
–30
–40
VDD
VSS
–50
–60
700
600
Code FFFFH
500
400
300
200
–70
Code 0000H
100
–80
1
800
OUTPUT NOISE vs FREQUENCY
Unipolar Configuration, Internal Reference Enabled
800
Output Noise (nV/Hz)
0
PSRR (dB)
900
Internal Reference Enabled
–VSS, VCC = 15V + 1Vp-p,
VDD = 5V + 0.5Vp-p
10
100
1k
10k
Frequency (Hz)
100k
1M
10M
0
0.01K
OUTPUT NOISE vs FREQUENCY
0.1K
1K
10K
100K
Frequency (Hz)
1M
10M
BROADBAND NOISE
Bipolar Configuration: ±10V, Internal Reference Enabled
600
VOUT (V, 50µV/div)
Output Noise (nV/√Hz)
700
500
400
Code 0000H
300
Code FFFFH
200
100
0
0.01K
Code 8000H
0.1K
1K
10K
100K
Frequency (Hz)
1M
10M
Time (100µs/div)
UNIPOLAR FULL-SCALE SETTLING TIME
BIPOLAR FULL-SCALE SETTLING TIME
Large-Signal Output (5V/div)
Large-Signal Output (5V/div)
Small-Signal Error (300µV/div)
Small-Signal Error (300µV/div)
Unipolar Configuration: VOUT = 0V to +10V
Zero-Scale to + Full-Scale Change
5kΩ, 200pF Load
Bipolar Configuration: VOUT = –10V to +10V
–Full-Scale to + Full-Scale Change
5kΩ, 200pF Load
Time (2µs/div)
10
Internal Reference Enabled
Filtered with 1.6Hz Low-Pass
Code FFFFH, Bipolar ±10V Configuration
10kHz Measurement BW
Time (2µs/div)
DAC7741
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TYPICAL CHARACTERISTICS (Cont.)
TA = +25°C (unless otherwise noted)
UNIPOLAR FULL-SCALE SETTLING TIME
BIPOLAR FULL-SCALE SETTLING TIME
Small-Signal Error (150µV/div)
Small-Signal Error (300µV/div)
Large-Signal Output (5V/div)
Large-Signal Output (5V/div)
Unipolar Configuration: VOUT = 0V to +10V
+Full-Scale to Zero-Scale Change
5kΩ, 200pF Load
Bipolar Configuration: VOUT = –10 to +10V
+Full-Scale to –Full-Scale
5kΩ, 200pF Load
Time (2µs/div)
Time (2µs/div)
MID-SCALE GLITCH
MID-SCALE GLITCH
Code 8000H to 7FFFH
Bipolar Configuration: ±10V VOUT
VOUT (V, 200mV/div)
VOUT (V, 200mV/div)
Code 7FFFH to 8000H
Bipolar Configuration: ±10V VOUT
Time (1µs/div)
Time (1µs/div)
DIGITAL FEEDTHROUGH
All Data Bits Toggling (5V/div)
VOUT = 8000H (100mV/div)
CS = 5V
Time (200ns/div)
DAC7741
SBAS248B
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11
THEORY OF OPERATION
The digital input is a parallel word made up of the 16-bit DAC
code, which is then loaded into the DAC register using the
LDAC input pin. The converter can be powered from ±12V
to ±15V dual analog supplies and a +5V logic supply. The
device offers a reset function, which immediately sets the
DAC output voltage and DAC register to min-scale (code
0000H) or mid-scale (code 8000H). The data I/O and reset
functions are discussed in more detail in the following sections.
The DAC7741 is a voltage output, 16-bit DAC with a +10V
built-in internal reference. The architecture is an R-2R ladder
configuration with the three MSBs segmented, followed by
an operational amplifier that serves as a buffer. The output
buffer is designed to allow user-configurable output adjustments, giving the DAC7741 output voltage ranges of 0V to
+10V, –5V to +5V, or –10V to +10V. Please refer to
Figures 2, 3, and 4 for pin configuration information.
REFADJ
REFOUT
REFIN
ROFFSET
VREF
RFB2
R/4
Buffer
RFB1
+10V Internal
Reference
R/2
R/2
R/4
SJ
R
VOUT
2R
2R
2R
2R
2R
2R
2R
2R
2R
R/4
VREF
AGND
FIGURE 1. DAC7741 Architecture.
REFEN
DB1
REFOUT
DB0
REFADJ
NC
REFIN
NC
14
NC
NC
DB6
DB5
DB4
20
DB3
NC
VSS
VCC
VREF
ROFFSET
AGND
AGND
RFB2
RFB1
SJ
VOUT
NC
2
3
4
5
6
7
8
9
10
11
12
19
21
22
NC
16
17
18
Data Bus
15
DB2
1
VSS
DAC7741
24
RSTSEL
NC
23
R/W
13
NC 25
TEST 26
DB7 27
DB8 28
DB9 29
DB10 30
42
DB11 31
41
CS
43
DB12 32
40
LDAC
44
DB13 33
39
RST
45
DB14 34
37
38
VDD
46
Control Bus
DGND
47
1µF
48
0.1µF
NC 36
VDD
DB15 35
Data Bus
(0V to +10V)
0.1µF
1µF
VCC
0.1µF
1µF
FIGURE 2. Basic Operation: VOUT = 0 to +10V.
12
DAC7741
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SBAS248B
REFEN
DB1
REFOUT
DB0
REFADJ
NC
REFIN
NC
14
NC
NC
DB6
DB5
DB4
20
DB3
8
NC
RFB2
7
12
AGND
6
VOUT
AGND
5
11
ROFFSET
4
SJ
VREF
9
VCC
3
10
VSS
2
RFB1
NC
19
21
22
NC
16
17
18
Data Bus
15
DB2
1
VSS
DAC7741
24
RSTSEL
NC
23
R/W
13
NC 25
DB7 27
TEST 26
DB8 28
DB9 29
DB10 30
42
DB11 31
41
CS
43
DB12 32
40
LDAC
44
DB13 33
39
RST
45
DB14 34
37
38
VDD
46
Control Bus
DGND
47
1µF
48
0.1µF
NC 36
VDD
DB15 35
Data Bus
(–5V to +5V)
0.1µF
1µF
VCC
0.1µF
1µF
FIGURE 3. Basic Operation: VOUT = –5V to +5V.
REFEN
DB1
REFOUT
DB0
REFADJ
NC
REFIN
NC
14
NC
NC
DB6
DB5
DB4
20
DB3
8
19
NC
RFB2
7
12
AGND
6
11
AGND
VOUT
ROFFSET
5
SJ
VREF
4
RFB1
VCC
3
9
VSS
2
10
NC
21
22
NC
16
17
18
Data Bus
15
DB2
1
VSS
DAC7741
24
RSTSEL
NC
23
R/W
13
NC 25
TEST 26
DB7 27
DB8 28
DB9 29
DB10 30
42
DB11 31
41
CS
43
DB12 32
40
LDAC
44
DB13 33
39
RST
45
DB14 34
37
38
VDD
46
Control Bus
DGND
47
1µF
48
0.1µF
NC 36
VDD
DB15 35
Data Bus
(–10V to +10V)
0.1µF
1µF
VCC
0.1µF
1µF
FIGURE 4. Basic Operation: VOUT = –10V to +10V.
DAC7741
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13
ANALOG OUTPUTS
The output amplifier can swing to within 1.4V of the supply
rails, specified over the –40°C to +85°C temperature range.
This allows for a ±10V DAC voltage output operation from
±12V supplies with a typical 5% tolerance.
When the DAC7741 is configured for a unipolar, 0V to 10V
output, a negative voltage supply is required. This is due to
internal biasing of the output stage. Please refer to the
“Electrical Characteristics” table for more information.
The minimum and maximum voltage output values are dependent upon the output configuration implemented and
reference voltage applied to the DAC7741. Please note that
VSS (the negative power supply) must be in the range of
–4.75V to –15.75V for unipolar operation. The voltage on VSS
sets several bias points within the converter and is required
in all modes of operation. If VSS is not in one of these two
configurations, the bias values may be in error and proper
operation of the device is not ensured.
Supply sequence is important in establishing the correct
startup of the DAC. The digital supply (VDD) needs to establish correct bias conditions before the analog supplies (VCC,
VSS) are brought up. If the digital supply cannot be brought
up first, it must come up before either analog supply (VCC or
VSS), with the preferred sequence of: VSS (device substrate),
VDD then VCC.
REFERENCE INPUTS
The DAC7741 provides a built-in +10V voltage reference and
on-chip buffer to allow external component reference drive. To
use the internal reference, REFEN must be LOW, enabling the
reference circuitry of the DAC7741 (see Table I) and the
REFOUT pin must be connected to REFIN. This is the input to
the on-chip reference buffer. The buffers output is provided at
REFEN
the VREF pin. In this configuration, VREF is used to setup the
DAC7741 output amplifier into one of three voltage output
modes as discussed earlier. VREF can also be used to drive
other system components requiring an external reference.
The internal reference of the DAC7741 can be disabled when
use of an external reference is desired. When using an
external reference, the reference input, REFIN , can be any
voltage between 4.75V (or VSS + 14V, whichever is greater)
and VCC – 1.4V.
DIGITAL INTERFACE
Table III shows the data format for the DAC7741 and
Table II illustrates the basic control logic of the device. The
interface consists of a chip select input (CS), read/write
control input (R/W), data inputs (DB0-DB15) and a load DAC
input (LDAC). An asynchronous reset input (RST) which is
active low, is provided to simplify start-up conditions, periodic
resets, or emergency resets to a known state, depending on
the status of the reset select (RSTSEL) signal. The DAC
code is provided via a 16-bit parallel interface, as shown in
Table II. The input word makes up the DAC code to be
loaded into the data input register of the device. The data is
latched into the input register on rising CS and is loaded into
the DAC register upon reception of a rising edge on the
LDAC input. This action updates the analog output, VOUT, to
the desired value. LDAC inputs of multiple DAC7741 devices
can be connected when a synchronized update of numerous
DAC outputs is desired. Please refer to the timing section for
more detailed data I/O information.
ANALOG OUTPUT
DIGITAL INPUT
Internal Reference disabled;
REFOUT = HIGH Impedance
0
Internal Reference enabled;
REFOUT = +10V
CS
L
X
H
Bipolar Offset Binary
0x0000
Zero (0V)
–Full-Scale (–VREF or –VREF/2)
0x0001
Zero + 1LSB
–Full-Scale + 1LSB
:
:
:
0x8000
1/2 Full-Scale
Bipolar Zero
0x8001
1/2 Full-Scale + 1LSB
Bipolar Zero + 1LSB
:
:
:
0xFFFF
Full-Scale (VREF – 1LSB)
+Full-Scale (+VREF – 1LSB
or +VREF/2 – 1LSB)
TABLE I. REFEN Action.
R/W
L
TABLE III. DAC7741 Data Format.
CONTROL STATUS
RST RSTSEL LDAC
H
X
H, L, ↓
H
X
Bipolar Configuration
Unipolar Straight Binary
ACTION
1
Unipolar Configuration
COMMAND
Input Register
Write
DAC Register
Hold
Mode
Write Data to Input Register
↑
Hold
Write
Update DAC register with data from input
register.
L
L
H
X
↑
Transparent
Write
Write DAC register directly from data bus
H
L
H
X
H, L, ↓
Read
Hold
Read data in input register.
X
H
H
X
H, L, ↓
Hold
Hold
No Change
X
X
L
L
X
Reset to Min-Scale Reset to Min-Scale Reset to Input and DAC Register (0000H)
Min-Scale
X
X
L
H
X
Reset to Mid-Scale Reset to Mid-Scale Reset to Input and DAC Register (8000H)
Mid-Scale
TABLE II. DAC7741 Logic Truth Table.
14
DAC7741
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SBAS248B
DAC RESET
(+VREF)
The RST and RSTSEL inputs control the reset of the analog
output. The reset command is level triggered by a low signal on
RST. Once RST is LOW, the DAC output will begin settling to
the mid-scale or min-scale code depending on the state of the
RSTSEL input. A HIGH value on RSTSEL will cause VOUT to
reset to the mid-scale code (8000H) and a LOW value will reset
VOUT to min-scale (0000H). A change in the state of the
RSTSEL input while RST is LOW will cause a corresponding
change in the reset command selected internally and consequently change the output value of VOUT of the DAC. Note that
a valid reset signal also resets the input register of the DAC to
the value specified by the state of RSTSEL.
+ Full Scale
Relationship of Offset and Gain Adjustments for
VOUT = 0V to +10V Output Configuration.
(+VREF or +VREF/2)
1LSB
Analog Output
Input =
FFFF H
– Full-Scale
(–VREF OR –VREF/2)
Digital Input
NC
VSS
VCC
VREF
ROFFSET
AGND
AGND
RFB2
RFB1
SJ
2
3
4
5
6
7
8
9
10
NC
RPOT1
VOUT
Relationship of Offset and Gain Adjustments
for VOUT = –10V to +10V Output Configuration.
(Same theory applies for VOUT = –5V to +5V).
11
FIGURE 6.
1
REFIN
18
Offset
Adjust
Translates
the Line
Input = 8000H
using potentiometers.
17
Gain
Adjust
Rotates
the Line
Full Scale
Range
Input =
0000H
When calibrating the DAC output, offset should be adjusted
first to avoid first order interaction of adjustments. In unipolar
mode, the DAC7741 offset is adjusted from code 0000H and
for either bipolar mode, offset adjustments are made at code
8000H. Gain adjustment can then be made at code FFFFH for
each configuration, where the output of the DAC should be
at +10V for the 0V to +10V – 1LSB or ±10V output range and
+5V – 1LSB for the ±5V output range. Figure 7 shows the
generalized external offset and gain adjustment circuitry
Optional Gain
Adjust
Digital Input
+ Full
Scale
respectively.
REFOUT
Full Scale Range
Analog Output
The architecture of the DAC7741 is designed in such a way
as to allow for easily configurable offset and gain calibration
using a minimum of external components. The DAC7741
has built-in feedback resistors and output amplifier summing
points brought out of the package in order to make the
absolute calibration possible. Figures 5 and 6 illustrate the
relationship of offset and gain adjustments for the DAC7741
in a unipolar configuration and in a bipolar configuration,
REFADJ
Input =
FFFF H
Offset Adjust Translates the Line
FIGURE 5.
16
Input =
0000 H
Zero Scale
(AGND)
GAIN AND OFFSET CALIBRATION
15
Gain Adjust
Rotates
the Line
1LSB
ISJ
R1
(Other Connections Omitted
for Clarity)
RS
RPOT2
+
VOADJ
–
Optional Offset
Adjust
FIGURE 7. Generalized External Calibration Circuitry for Gain and Symmetrical Offset Adjustment.
DAC7741
SBAS248B
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15
OFFSET ADJUSTMENT
Offset adjustment is accomplished by introducing a small
current into the summing junction (SJ) of the DAC7741. The
voltage at SJ, or VSJ, is dependent on the output configuration of the DAC7741. See Table IV for the required pin
strapping for a given configuration and the nominal values of
VSJ for each output range.
than 100kΩ) as shown in Figure 7. Since the input impedance of REFADJ is typically 50kΩ, the smaller the resistance
of the potentiometer, the more linear the adjustment will be.
A 10kΩ potentiometer is suggested if linearity of the reference adjustment is of concern.
OFFSET ADJUST RANGE
VSJ(1)
REFERENCE
OUTPUT
PIN STRAPPING
CONFIGURATION CONFIGURATION ROFFSET RFB1 RFB2
External
Reference
0V to +10V
–10V to +10V
–5V to +5V
+5V
to VREF to VOUT to VOUT
NC
NC to VOUT +3.333V
to AGND to VOUT to VOUT +1.666V
to VREF to VOUT to VOUT
0V to VREF
–VREF to VREF
NC
NC to VOUT
–VREF/2 to VREF/2 to AGND to VOUT to VOUT
VREF/2
VREF/3
VREF/6
NOTE: (1) Voltage measured at VSJ for a given configuration.
TABLE IV. Nominal VSJ vs. VOUT and Reference Configuration.
The current level required to adjust the DAC7741 offset can
be created by using a potentiometer divider as shown in
Figure 7. Another alternative is to use a unipolar DAC in
order to apply a voltage, VOADJ, to the resistor RS. A ±2uA
current range applied to SJ will ensure offset adjustment
coverage of the ±0.1% maximum offset specification of the
DAC7741.
When in a unipolar configuration (VSJ = 5V), only a single
resistor, RS, is needed for symmetrical offset adjustment with
a 0V to 10V VOADJ range. When in one of the two bipolar
configurations, VSJ is either +3.333v (±10V range) or +1.666V
(±5V range), and circuit values chosen to match those given
in Table V will provide symmetrical offset adjust. Please refer
to Figure 7 for component configuration.
OUTPUT
RPOT2
CONFIGURATION
0V to +10V
–10V to +10V
–5V to +5V
10K
10K
10K
R1
0
5K
20K
RS
2.5M
1.5M
1M
ISJ
RANGE
±2µA
±2.2µA
±1.7µA
min (75% of typ)
25
typ
0
min (75% of typ)
0V to 10V and –5V to +5V
VOUT Configuration
–25
–2
–1
Figure 8 illustrates the typical and minimum offset adjustment
ranges provided by forcing a current at SJ for a given output
voltage configuration.
1
2
FIGURE 8. Offset Adjustment Transfer Characteristic.
When the DAC7741 internal reference is not used, gain
adjustments can be made via trimming the external reference applied to the DAC at REFIN. This can be accomplished
through using a potentiometer, unipolar DAC, or other means
of precision voltage adjustment to control the voltage presented to the DAC7741 by the external reference. Figure 9
and Table VI summarize the range of adjustment of the
internal reference via REFADJ.
REFOUT ADJUST RANGE
40
Typical REFOUT
Adjustment Range
30
TABLE V. Recommended External Component Values for
Symmetrical Offset Adjustment (VREF = 10V).
0
ISJ (µA)
NOMINAL
OFFSET
ADJUSTMENT
±25mV
±55mV
±21mV
typ –10V to +10V VOUT
Configuration
–50
REFOUT Adjustment (mV)
Internal
Reference
Offset Adjustment at VOUT (mV)
50
20
10
Minimum REFOUT
Adjustment Range
0
–10
–20
–30
–40
GAIN ADJUSTMENT
When using the internal reference of the DAC7741, gain
adjustment is performed by adjusting the internal reference voltage via the reference adjust pin, REFADJ. The
effect of a reference voltage change on the gain of the
DAC output can be seen in the generic equation (for
unipolar configuration):
0
6
8
10
FIGURE 9. Internal Reference Adjustment Transfer Characteristic.
where N is represented in decimal format and ranges from 0
to 65535.
16
4
REFADJ (V)
VOUT = VREFIN • (N/65536)
REFADJ can be driven by a low impedance voltage source
such as a unipolar, 0V to +10V DAC or a potentiometer (less
2
VOLTAGE AT REFADJ
REFOUT VOLTAGE
REFADJ = 0V
REFADJ = 5V or NC(1)
REFADJ = 10V
10V + 25mV (min)
10V
10V – 25mV (max)
NOTE: "NC" is "Not Connected"
TABLE VI. Minimum Internal Reference Adjustment Range.
DAC7741
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SBAS248B
NOISE PERFORMANCE
Increased noise performance of the DAC output can be
achieved by filtering the voltage reference input to the
DAC7741. Figure 10 shows a typical internal reference filter
schematic. A low-pass filter applied between the REFOUT and
REFIN pins can increase noise immunity at the DAC and
output amplifier. The REFOUT pin can source a maximum of
50µA so care should be taken in order to avoid overloading
the internal reference output.
46
REFADJ
47
REFIN
48
NC
VCC
REFOUT
3
45
VSS
REFEN
2
(Other Connections
Omitted for Clarity)
44
NC
1µF
RSTSEL
A precision analog component requires careful layout, adequate
bypassing, and clean, well-regulated power supplies. The
DAC7741 offers separate digital and analog supplies, as it will
often be used in close proximity with digital logic, microcontrollers,
microprocessors, and digital signal processors. The more digital
logic present in the design and the higher the switching speed,
the more important it will become to separate the analog and
digital ground and supply planes at the device.
Since the DAC7741 has both analog and digital ground pins,
return currents can be better controlled and have less effect
on the DAC output error. Ideally, AGND would be connected
directly to an analog ground plane and DGND to the digital
ground plane. The analog ground plane would be separate
from the ground connection for the digital components until
they were connected at the power entry point of the system.
1
100kΩ
43
LAYOUT
FIGURE 10. Internal Reference Filter.
The voltages applied to VCC and VSS should be well regulated
and low noise. Switching power supplies and dc/dc converters will often have high-frequency glitches or spikes riding on
the output voltage. In addition, digital components can create
similar high-frequency spikes as their internal logic switches
states. This noise can easily couple into the DAC output
voltage through various paths between the power connections and analog output.
In addition, a 1µF to 10µF bypass capacitor in parallel with a
0.1µF bypass capacitor is strongly recommended for each
supply input. In some situations, additional bypassing may
be required, such as a 100µF electrolytic capacitor or even
a "Pi" filter made up of inductors and capacitors–all designed
to essentially low-pass filter the analog supplies, removing
any high frequency noise components.
DAC7741
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17
PACKAGE OPTION ADDENDUM
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14-Oct-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
DAC7741YB/250
ACTIVE
LQFP
PT
48
250
RoHS & Green
Call TI
Level-3-260C-168 HR
-40 to 85
DAC7741Y
B
Samples
DAC7741YC/250
ACTIVE
LQFP
PT
48
250
RoHS & Green
Call TI
Level-3-260C-168 HR
-40 to 85
DAC7741Y
C
Samples
DAC7741YL/250
ACTIVE
LQFP
PT
48
250
RoHS & Green
Call TI
Level-3-260C-168 HR
0 to 70
DAC7741Y
L
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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