DAC
DAC
764
764
2
DAC7642
DAC7643
3
SBAS233 – DECEMBER 2001
16-Bit, Dual Voltage Output
DIGITAL-TO-ANALOG CONVERTER
FEATURES
DESCRIPTION
●
●
●
●
The DAC7642 and DAC7643 are dual channel, 16-bit, voltage output Digital-to-Analog Converters (DACs) which provide 15-bit monotonic performance over the specified temperature range. They accept 16-bit parallel input data, have
double-buffered DAC input logic (allowing simultaneous update of all DACs), and provide a readback mode of the
internal input registers. Programmable asynchronous reset
clears all registers to a mid-scale code of 8000H (DAC7642)
or to a zero-scale code of 0000H (DAC7643). These DACs
can operate from a single +5V supply or from +5V and –5V
supplies, providing an output range of 0 to +2.5V or –2.5V to
+2.5V, respectively.
LOW POWER: 4mW
UNIPOLAR OR BIPOLAR OPERATION
SETTLING TIME: 10µs to 0.003% FSR
15-BIT LINEARITY AND MONOTONICITY:
–40°C to +85°C
● RESET TO MID-SCALE (DAC7642) OR
ZERO-SCALE (DAC7643)
● DATA READBACK
● DOUBLE-BUFFERED DATA INPUTS
APPLICATIONS
●
●
●
●
●
Low power and small size per DAC make the DAC7642 and
DAC7643 ideal for automatic test equipment, DAC-per-pin
programmers, data acquisition systems, and closed-loop
servo-control. The DAC7642 and DAC7643 are available in
a LQFP-32 package and specified over a –40°C to +85°C
temperature range.
PROCESS CONTROL
CLOSED-LOOP SERVO-CONTROL
MOTOR CONTROL
DATA ACQUISITION SYSTEMS
DAC-PER-PIN PROGRAMMERS
VCC
VREFL
Sense
VSS
VREFL
VREFH
VREFH
Sense
DAC7642
DAC7643
16
DATA I/O
I/O
Buffer
Input
Register A
DAC
Register A
DAC A
VOUTA
VOUTA Sense
Input
Register B
DACSEL
CS
R/W
DAC
Register B
DAC B
VOUTB
VOUTB Sense
Control
Logic
GND
RST
LOADDACS
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.
Copyright © 2001, 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 11V
VCC to GND .......................................................................... –0.3V to 5.5V
VREFL to VSS ............................................................. –0.3V to (VCC – VSS)
VCC to VREFH ............................................................ –0.3V to (VCC – VSS)
VREFH to VREFL ......................................................... –0.3V to (VCC – VSS)
Digital Input Voltage to GND ................................... –0.3V to VCC + 0.3V
Digital Output Voltage to GND ................................. –0.3V to VCC + 0.3V
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ........................................ –40°C to +85°C
Storage Temperature Range ......................................... –65°C to +125°C
Lead Temperature (soldering, 10s) ............................................... +300°C
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.
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.
PACKAGE/ORDERING INFORMATION
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
MARKING
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
DAC7642VFT
DAC7642VFR
Tape and Reel, 250
Tape and Reel, 1000
DAC7642VFB T
DAC7642VFB R
Tape and Reel, 250
Tape and Reel, 1000
DAC7643VFT
DAC7643VFR
Tape and Reel, 250
Tape and Reel, 1000
DAC7643VFB T
DAC7643VFB R
Tape and Reel, 250
Tape and Reel, 1000
MONOTONICITY
PACKAGE-LEAD
PACKAGE
DESIGNATOR(1)
DAC7642VF
14 Bits
LQFP-32
VF
–40°C to +85°C
DAC7642
"
"
"
"
"
"
DAC7642VFB
15 Bits
LQFP-32
VF
–40°C to +85°C
DAC7642B
"
"
"
"
"
"
DAC7643VF
14 Bits
LQFP-32
VF
–40°C to +85°C
DAC7643
"
"
"
"
"
"
DAC7643VFB
15 Bits
LQFP-32
VF
–40°C to +85°C
DAC7643B
"
"
"
"
"
"
PRODUCT
NOTE: (1) For the most current specifications and package information, refer to our web site at www.ti.com.
2
DAC7642, DAC7643
www.ti.com
SBAS233
ELECTRICAL CHARACTERISTICS (Dual Supply)
At TA = TMIN to TMAX, VCC = +5V, VSS = –5V, VREFH = +2.5V, and VREFL = –2.5V, unless otherwise noted.
DAC7642VF
DAC7643VF
PARAMETER
ACCURACY
Linearity Error
Linearity Match
Differential Linearity Error
Monotonicity, TMIN to TMAX
Bipolar Zero Error
Bipolar Zero Error Drift
Full-Scale Error
Full-Scale Error Drift
Bipolar Zero Matching
Full-Scale Matching
Power-Supply Rejection Ratio (PSRR)
ANALOG OUTPUT
Voltage Output
Output Current
Maximum Load Capacitance
Short-Circuit Current
Short-Circuit Duration
CONDITIONS
MIN
MAX
±3
±4
±2
±4
R L = 10kΩ
VREFL
–1.25
No Oscillation
MIN
±3
±3
10
±3
10
±3
±3
100
VREFH
+1.25
VREFL + 1.25
–2.5
+2.5
VREFH – 1.25
8
0.5
2
60
40
f = 10kHz
7FFFH to 8000H or 8000H to 7FFFH
UNITS
±2
±2
±1
±3
✻
✻
✻
✻
±1
±1
✻
✻
✻
✻
✻
±3
±3
✻
LSB
LSB
LSB
Bits
mV
ppm/°C
mV
ppm/°C
mV
mV
ppm/V
✻
✻
✻
✻
✻
✻
✻
10
POWER SUPPLY
VCC
VSS
ICC
ISS
Power
TEMPERATURE RANGE
Specified Performance
+4.75
–5.25
–1.2
–40
V
mA
pF
mA
✻
✻
V
V
µA
µA
✻
µs
LSB
nV-s
nV/√Hz
nV-s
✻
0.3 • VCC
±10
±10
3.6
✻
✻
✻
✻
0.7 • VCC
IOH = –0.8mA
IOL = 1.2mA
±2
✻
✻
✻
500
–500
To ±0.003%, 5V Output Step
See Figure 5
MAX
✻
✻
500
–10, +30
Indefinite
GND, VCC or VSS
TYP
15
±1
5
±1
5
±1
±1
10
Channel-to-Channel Matching
Channel-to-Channel Matching
At Full-Scale
DIGITAL INPUT
VIH
VIL
IIH
IIL
DIGITAL OUTPUT
VOH
VOL
TYP
14
REFERENCE INPUT
Ref High Input Voltage Range
Ref Low Input Voltage Range
Ref High Input Current
Ref Low Input Current
DYNAMIC PERFORMANCE
Settling Time
Channel-to-Channel Crosstalk
Digital Feedthrough
Output Noise Voltage
DAC Glitch
DAC7642VFB
DAC7643VFB
4.5
0.3
+5.0
–5.0
0.7
–0.8
7.5
✻
0.4
+5.25
–4.75
1.1
✻
✻
✻
11.5
+85
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
V
V
µA
µA
✻
V
V
✻
✻
✻
✻
V
V
mA
mA
mW
✻
°C
✻ Specifications same as DAC7642VF and DAC7643VF.
DAC7642, DAC7643
SBAS233
www.ti.com
3
ELECTRICAL CHARACTERISTICS (Single Supply)
At TA = TMIN to TMAX, VCC = +5V, VSS = 0V, VREFH = +2.5V, and VREFL = 0V, unless otherwise noted.
DAC7642VF
DAC7643VF
PARAMETER
ACCURACY
Linearity Error(1)
Linearity Match
Differential Linearity Error
Monotonicity, TMIN to TMAX
Zero-Scale Error
Zero-Scale Error Drift
Full-Scale Error
Full-Scale Error Drift
Zero-Scale Matching
Full-Scale Matching
Power-Supply Rejection Ratio (PSRR)
ANALOG OUTPUT
Voltage Output
Output Current
Maximum Load Capacitance
Short-Circuit Current
Short-Circuit Duration
CONDITIONS
MIN
MAX
±3
±4
±2
±4
RL = 10kΩ
0
–1.25
No Oscillation
MIN
±3
±3
10
±3
10
±3
±3
100
VREFH
+1.25
VREFL + 1.25
0
+2.5
VREFH – 1.25
8
0.5
2
60
40
7FFFH to 8000H or 8000H to 7FFFH
UNITS
±2
±2
±1
±3
✻
✻
✻
✻
±1
±1
✻
✻
✻
✻
✻
±3
±3
✻
LSB
LSB
LSB
Bits
mV
ppm/°C
mV
ppm/°C
mV
mV
ppm/V
✻
✻
✻
✻
✻
✻
✻
10
POWER SUPPLY
VCC
VSS
ICC
Power
TEMPERATURE RANGE
Specified Performance
+4.75
0
–40
V
mA
pF
mA
✻
✻
V
V
µA
µA
✻
µs
LSB
nV-s
nV/√Hz
nV-s
✻
✻
✻
✻
V
V
µA
µA
✻
✻
✻
V
V
✻
✻
✻
✻
✻
✻
✻
✻
V
V
mA
mW
✻
°C
0.3 • VCC
±10
±10
3.6
✻
✻
✻
✻
0.7 • VCC
IOH = –0.8mA
IOL = 1.2mA
±2
✻
✻
✻
250
–250
To ±0.003%, 2.5V Output Step
See Figure 6
MAX
✻
✻
500
–10, +30
Indefinite
GND or VCC
TYP
15
±1
5
±1
5
±1
±1
10
Channel-to-Channel Matching
Channel-to-Channel Matching
At Full-Scale
DIGITAL INPUT
VIH
VIL
IIH
IIL
DIGITAL OUTPUT
VOH
VOL
TYP
14
REFERENCE INPUT
Ref High Input Voltage Range
Ref Low Input Voltage Range
Ref High Input Current
Ref Low Input Current
DYNAMIC PERFORMANCE
Settling Time
Channel-to-Channel Crosstalk
Digital Feedthrough
Output Noise Voltage, f = 10kHz
DAC Glitch
DAC7642VFB
DAC7643VFB
✻
4.5
0.3
0.4
+5.0
0
0.5
2.5
+5.25
0
0.9
4.5
✻
✻
+85
✻
✻ Specifications same as DAC7642VF and DAC7643VF.
NOTE: (1) If VSS = 0V, specification applies at Code 0040H and above due to possible negative zero-scale error.
4
DAC7642, DAC7643
www.ti.com
SBAS233
PIN CONFIGURATION
25 VOUTB
26 VOUTB Sense
27 VREFH Sense
28 VREFH
29 VREFL
30 VREFL Sense
31 VOUTA Sense
LQFP
32 VOUTA
Top View
VCC
1
24
VSS
GND
2
23
DACSEL
DB15
3
22
RST
DB14
4
21
LOADDACS
DB13
5
20
R/W
DB12
6
19
CS
DB11
7
18
DB0
DB10
8
17
DB1
16
DB2
13
DB5
15
12
DB6
DB3
11
DB7
14
10
DB8
DB4
9
DB9
DAC7642
DAC7643
PIN DESCRIPTIONS
PIN
NAME
DESCRIPTION
PIN
NAME
1
VCC
Positive Power Supply
20
R/W
2
GND
Ground
Enabled by CS, Controls Data Read from and Write
to the Input Registers.
DESCRIPTION
3
DB15
Data Bit 15, MSB
21
LOADDACS
4
DB14
Data Bit 14
DAC Output Registers Load Control. Rising edge
triggered. Transfers Data from the Input Registers to
the DAC Registers, Updating the DAC Output.
5
DB13
Data Bit 13
22
RST
6
DB12
Data Bit 12
7
DB11
Data Bit 11
Reset, Rising Edge Triggered. DAC7642 resets to
mid-scale, DAC7643 resets to zero. (Resets Both
Input Registers and DAC Registers)
8
DB10
Data Bit 10
23
DACSEL
Enabled by CS. Selects the individual DAC Input
Registers. (LOW Selects Register A, HIGH Selects
Register B)
VSS
Negative Power Supply
DAC B Voltage Output
9
DB9
Data Bit 9
10
DB8
Data Bit 8
24
11
DB7
Data Bit 7
25
VOUTB
12
DB6
Data Bit 6
26
VOUTB Sense
13
DB5
Data Bit 5
14
DB4
Data Bit 4
27
VREFH Sense
28
VREFH
DAC A and B Reference High Input
29
VOUTL
DAC A and B Reference Low Input
15
DB3
Data Bit 3
16
DB2
Data Bit 2
17
DB1
Data Bit 1
18
DB0
Data Bit 0, LSB
19
CS
Chip Select, Active LOW
DAC A and B Reference High Sense Input
30
VREFL Sense
DAC A and B Reference Low Sense Input
31
VOUTA Sense
DAC A Output Amplifier Inverting Input. Used to
close the feedback loop at the load.
32
VOUTA
DAC7642, DAC7643
SBAS233
DAC B Output Amplifier Inverting Input. Used to
close the feedback loop at the load.
www.ti.com
DAC A Output Voltage
5
TYPICAL CHARACTERISTICS: VSS = 0V
At TA = +25°C, VCC = +5V, VSS = 0V, VREFH = +2.5V, VREFL = 0V, representative unit, unless otherwise specified.
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
LE (LSB)
Digital Input Code
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +85°C)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC B, +85°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
DLE (LSB)
LE (LSB)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, –40°C)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC B, –40°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
6
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
Digital Input Code
LE (LSB)
LE (LSB)
DLE (LSB)
DLE (LSB)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
–40°C
LE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC B, +25°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
+85°C
DLE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +25°C)
DLE (LSB)
DLE (LSB)
LE (LSB)
+25°C
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
DAC7642, DAC7643
www.ti.com
SBAS233
TYPICAL CHARACTERISTICS: VSS = 0V (Cont.)
At TA = +25°C, VCC = +5V, VSS = 0V, VREFH = +2.5V, VREFL = 0V, representative unit, unless otherwise specified.
POSITIVE FULL-SCALE ERROR vs TEMPERATURE
NEGATIVE FULL-SCALE ERROR vs TEMPERATURE
3
Code (0040H)
2
Positive Full-Scale Error (mV)
Negative Full-Scale Error (mV)
3
DAC A
1
0
DAC B
–1
–2
DAC A
1
0
DAC B
–1
–2
–3
–3
–40
–15
10
35
60
–40
85
–15
35
Temperature (°C)
VREFH CURRENT vs CODE
(all DACs sent to indicated code)
VREFL CURRENT vs CODE
(all DACs sent to indicated code)
0.30
0.00
0.25
–0.05
0.20
0.15
0.10
60
85
–0.10
–0.15
–0.20
0.05
–0.25
0.00
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
–0.30
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
SUPPLY CURRENT vs TEMPERATURE
SUPPLY CURRENT vs DIGITAL INPUT CODE
1
1.0
Data = FFFFH (all DACs)
No Load
No Load
0.8
0.8
0.6
0.6
ICC (mA)
ICC (mA)
10
Temperature (°C)
VREF Current (mA)
VREF Current (mA)
Code (FFFFH)
2
0.4
0.2
All DACs
0.4
0.2
0
–40
–15
10
35
60
0.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
85
Temperature (°C)
Digital Input Code
DAC7642, DAC7643
SBAS233
www.ti.com
7
TYPICAL CHARACTERISTICS: VSS = 0V (Cont.)
At TA = +25°C, VCC = +5V, VSS = 0V, VREFH = +2.5V, VREFL = 0V, representative unit, unless otherwise specified.
OUTPUT VOLTAGE vs SETTLING TIME
(0V to +2.5V)
Large-Signal Settling Time: 1V/div
OUTPUT VOLTAGE vs SETTLING TIME
(+2.5V to 2mV)
+5V
LDAC
0
Output Voltage
Output Voltage
Small-Signal Settling
Time: 500µV/div
Small-Signal Settling Time: 500µV/div
Large-Signal Settling Time: 1V/div
+5V
LDAC
0
Time (2µs/div)
Time (2µs/div)
OUTPUT VOLTAGE
vs MIDSCALE GLITCH PERFORMANCE
OUTPUT VOLTAGE
vs MIDSCALE GLITCH PERFORMANCE
+5V
LDAC
0
Output Voltage (20mV/div)
Output Voltage (20mV/div)
+5V
LDAC
0
7FFFH to 8000H
8000H to 7FFFH
Time (1µs/div)
Time (1µs/div)
BROADBAND NOISE
OUTPUT NOISE VOLTAGE vs FREQUENCY
Noise (nV/√Hz)
Noise Voltage (50µV/div)
1000
100
10
10
Time (10µs/div)
100
1000
10000
100000
1000000
Frequency (Hz)
8
DAC7642, DAC7643
www.ti.com
SBAS233
TYPICAL CHARACTERISTICS: VSS = 0V (Cont.)
At TA = +25°C, VCC = +5V, VSS = 0V, VREFH = +2.5V, VREFL = 0V, representative unit, unless otherwise specified.
LOGIC SUPPLY CURRENT
vs LOGIC INPUT LEVEL FOR DIGITAL INPUTS
VOUT vs RLOAD
5
Typical of One
Digital Input
0.40
4
0.30
3
VOUT (V)
Logic Supply Current (mA)
0.50
0.20
Source
2
0.10
1
0.00
0
0.01
1
0
2
3
4
5
Sink
0.1
1
10
100
RLOAD (kΩ)
Logic Input Level for Digital Inputs (V)
VSS = –5V
At TA = +25°C, VCC = +5V, VSS = –5V, VREFH = +2.5V, VREFL = –2.5V, representative unit, unless otherwise specified.
LE (LSB)
DLE (LSB)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +85°C)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC B, +85°C)
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
LE (LSB)
LE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC B, +25°C)
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
+85°C
DLE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +25°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
DLE (LSB)
DLE (LSB)
LE (LSB)
+25°C
Digital Input Code
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
DAC7642, DAC7643
SBAS233
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
www.ti.com
9
TYPICAL CHARACTERISTICS: VSS = –5V (Cont.)
At TA = +25°C, VCC = +5V, VSS = –5V, VREFH = +2.5V, VREFL = –2.5V, representative unit, unless otherwise specified.
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, –40°C)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC B, –40°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
DLE (LSB)
LE (LSB)
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
VREFH CURRENT vs CODE
(all DACs sent to indicated code)
VREFL CURRENT vs CODE
(all DACs sent to indicated code)
0.6
0.0
0.5
–0.1
VREF Current (mA)
VREF Current (mA)
DLE (LSB)
LE (LSB)
–40°C
0.4
0.3
0.2
–0.2
–0.3
–0.4
0.1
–0.5
0.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
–0.6
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
POSITIVE FULL-SCALE ERROR vs TEMPERATURE
BIPOLAR ZERO ERROR vs TEMPERATURE
3
3
Bipolar Zero Error (mV)
Positive Full-Scale Error (mV)
Code (8000H)
2
DAC A
1
0
–1
DAC B
–2
DAC A
1
0
–1
DAC B
–2
–3
–3
–40
–15
10
35
60
–40
85
–15
10
35
60
85
Temperature (°C)
Temperature (°C)
10
Code (FFFFH)
2
DAC7642, DAC7643
www.ti.com
SBAS233
TYPICAL CHARACTERISTICS: VSS = –5V (Cont.)
At TA = +25°C, VCC = +5V, VSS = –5V, VREFH = +2.5V, VREFL = –2.5V, representative unit, unless otherwise specified.
NEGATIVE FULL-SCALE ERROR vs TEMPERATURE
SUPPLY CURRENT vs DIGITAL INPUT CODE
1.00
Code (0000H)
No Load
ICC
0.75
2
DAC A
Supply Current (mA)
Negative Full-Scale Error (mV)
3
1
0
DAC B
–1
–2
0.50
0.25
0.00
–0.25
–0.50
–0.75
ISS
–1.00
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
–3
–40
–15
10
35
60
85
Temperature (°C)
Digital Input Code
VOUT vs RLOAD
SUPPLY CURRENT vs TEMPERATURE
5
1
ICC
4
Source
0.5
Supply Current (mA)
3
VOUT (V)
2
1
0
–1
Sink
–2
–3
0
–0.5
ISS
–1
Data = FFFFH (all DACs)
No Load
–4
–5
0.01
–1.5
0.1
1
10
100
–40
–15
10
35
60
RLOAD (kΩ)
Temperature (°C)
OUTPUT VOLTAGE vs SETTLING TIME
(–2.5V to +2.5V)
OUTPUT VOLTAGE vs SETTLING TIME
(+2.5V to –2.5V)
85
+5V
LDAC
0
Output Voltage
Output Voltage
Large-Signal Settling Time: 2V/div
Small-Signal Settling Time: 500µV/div
Small-Signal Settling Time:
500µV/div
Large-Signal Settling Time: 2V/div
+5V
LDAC
0
Time (2µs/div)
Time (2µs/div)
DAC7642, DAC7643
SBAS233
www.ti.com
11
TYPICAL CHARACTERISTICS: VSS = –5V (Cont.)
At TA = +25°C, VCC = +5V, VSS = –5V, VREFH = +2.5V, VREFL = –2.5V, representative unit, unless otherwise specified.
OUTPUT VOLTAGE
vs MIDSCALE GLITCH PERFORMANCE
Output Voltage (50mV/div)
Output Voltage (50mV/div)
OUTPUT VOLTAGE
vs MIDSCALE GLITCH PERFORMANCE
7FFFH to 8000H
8000H to 7FFFH
+5V
LDAC
0
+5V
LDAC
0
Time (1µs/div)
Time (1µs/div)
THEORY OF OPERATION
by the external voltage references VREFL and VREFH, respectively. The digital input is a 16-bit parallel word and the DAC
input registers offer a readback capability. The converters
can be powered from either a single +5V supply or a dual
±5V supply. Each device offers a reset function which immediately sets all DAC output voltages, DAC registers and Input
registers to mid-scale, code 8000H (DAC7642), or to zeroscale, code 0000H (DAC7643). See Figures 2 and 3 for the
basic configurations of the DAC7642 and DAC7643.
The DAC7642 and DAC7643 are dual channel, voltage
output, 16-bit DACs. The architecture is an R-2R ladder
configuration with the three MSB’s segmented followed by an
operational amplifier that serves as a buffer. Each DAC has
its own R-2R ladder network, segmented MSBs, and output
op amp, as shown in Figure 1. The minimum voltage output
(zero-scale) and maximum voltage output (full-scale) are set
RF
VOUT Sense
VOUT
R
2R
2R
2R
2R
2R
2R
2R
2R
2R
VREFH
VREFH Sense
VREFL
VREFL Sense
FIGURE 1. DAC7642 and DAC7643 Architecture.
12
DAC7642, DAC7643
www.ti.com
SBAS233
0V to +2.5V
32
+2.5V
31
VOUTA
1
+5V
1µF
0.1µF 2
3
4
5
DATA BUS
6
7
8
30
29
28
0V to +2.5V
27
VREFH
VREFL
Sense
VOUTA
Sense
26
25
VOUTB
Sense
VREFH
Sense
VREFL
VOUTB
VSS
VCC
GND
DACSEL
DB15
RST
DAC7642
DAC7643
DB14
LDAC
DB13
R/W
DB12
CS
DB11
DB0
DB10
DB1
24
23
SELECT DAC CHANNEL
22
RESET DAC REGISTERS
21
LOAD DAC REGISTERS
20
READ/WRITE
19
CHIP SELECT
18
17
DATA BUS
DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2
9
10 11 12 13 14 15 16
FIGURE 2. Basic Single-Supply Operation of the DAC7642 and DAC7643.
–2.5V to
+2.5V
32
31
+5V
1µF
0.1µF 2
3
4
5
DATA BUS
6
7
8
30
29
VREFL
Sense
VOUTA
1
+2.5V
–2.5V
VOUTA
Sense
28
27
26
25
VOUTB
Sense
VREFH
VREFL
–2.5V to
+2.5V
VREFH
Sense
VOUTB
1µF
VSS
VCC
GND
DACSEL
DB15
DB14
RST
DAC7642
DAC7643
DB13
LDAC
R/W
DB12
CS
DB11
DB0
DB10
DB1
0.1µF
24
–5V
23
SELECT DAC CHANNEL
22
RESET DAC REGISTERS
21
LOAD DAC REGISTERS
20
READ/WRITE
19
CHIP SELECT
18
17
DATA BUS
DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2
9
10 11 12 13 14 15 16
FIGURE 3. Basic Dual-Supply Operation of the DAC7642 and DAC7643.
DAC7642, DAC7643
SBAS233
www.ti.com
13
ANALOG OUTPUTS
When VSS = –5V (dual-supply operation), the output amplifier
can swing to within 2.25V of the supply rails over the –40°C
to +85°C temperature range. When VSS = 0V (single-supply
operation), and with RLOAD also connected to ground, the
output can swing to ground. Care must also be taken when
measuring the zero-scale error when VSS = 0V. Since the
DAC output cannot swing below ground, the output voltage
may not change for the first few digital input codes (0000H,
0001H, 0002H, etc.) if the output amplifier has a negative
offset. At the negative limit of –2mV, the first specified output
starts at code 0040H.
Due to the high accuracy of these DACs, system design
problems such as grounding and contact resistance become
very important. A 16-bit converter with a 2.5V full-scale range
has a 1LSB value of 38µV. With a load current of 1mA, a series
wiring and connector resistance of only 40mΩ (RW2) will cause
a voltage drop of 40µV, as shown in Figure 4. To understand
what this means in terms of a system layout, the resistivity of
a typical 1 ounce copper-clad printed circuit board is 1/2 mΩ
per square. For a 1mA load, a 10 milli-inch wide printed circuit
conductor 600 milli-inches long will result in a voltage drop of
30µV.
The DAC7642 and DAC7643 offer a force and sense output
configuration for the high open-loop gain output amplifiers.
This feature allows the loop around the output amplifier to be
closed at the load (shown in Figure 4), thus ensuring an
accurate output voltage.
REFERENCE INPUTS
The reference inputs, VREFL and VREFH, can be any voltage
between VSS + 2.5V and VCC – 2.5V provided that VREFH is
at least 1.25V greater than VREFL. The minimum output of
each DAC is equal to VREFL plus a small offset voltage
(essentially, the offset of the output op amp). The maximum
output is equal to VREFH plus a similar offset voltage. Note
RW2
DAC7642
DAC7643
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
VREFH Sense
27
VOUTB Sense
26
VOUTB
25
RW1
VOUT
+V
+2.5V
RW1
VOUT
RW2
FIGURE 4. Analog Output Closed-Loop Configuration. RW
represents wiring resistances.
that VSS (the negative power supply) must either be connected to ground or must be in the range of –4.75V to
–5.25V. The voltage on VSS sets several bias points within
the converter. If VSS is not in one of these two configurations,
the bias values may be in error and proper operation of the
device may be affected.
The current into the VREFH input and out of VREFL depends
on the DAC output voltages and can vary from a few
microamps to approximately 0.5mA. The reference input
appears as a varying load to the reference. If the references
applied can sink or source the required current, a reference
buffer is not required. The DAC7642 and DAC7643 feature
reference drive and sense connections such that the internal
errors caused by the changing reference current and the
circuit impedances can be minimized. Figures 5 through 13
show different reference configurations and the effect on the
linearity and differential linearity.
+V
DAC7642
DAC7643
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
OPA2234
VOUT
100Ω
1000pF
–V
+V
1000pF
VREFH Sense
27
VOUTB Sense
26
VOUTB
25
–2.5V
2200pF
100Ω
+2.5V
2200pF
VOUT
–V
FIGURE 5. Dual Supply Configuration-Buffered References, Used for Dual-Supply Characteristic Curves.
14
DAC7642, DAC7643
www.ti.com
SBAS233
+V
DAC7642
DAC7643
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
OPA2350
VOUT
100Ω
27
VOUTB Sense
26
VOUTB
25
2kΩ
1000pF
+0.050V
98kΩ
+V
100Ω
1000pF
VREFH Sense
2200pF
+2.5V
2200pF
VOUT
FIGURE 6. Single-Supply Buffered Reference with VREFL of 50mV.
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +25°C)
LE (LSB)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
DLE (LSB)
DLE (LSB)
LE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +25°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
FIGURE 7. Integral Linearity and Differential Linearity Error
Curves for Figure 6.
FIGURE 8. Integral Linearity and Differential Linearity Error
Curves for Figure 9.
+V
+V
DAC7642
DAC7643
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
VREFH Sense
27
VOUTB Sense
26
VOUTB
25
OPA2350
VOUT
100Ω
+1.25V
2200pF
1000pF
+V
1000pF
100Ω
2200pF
+2.5V
VOUT
FIGURE 9. Single-Supply Buffered Reference with VREFL = +1.25V and VREFH = +2.5V.
DAC7642, DAC7643
SBAS233
www.ti.com
15
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
VREFH Sense
27
VOUTB Sense
26
VOUTB
25
DAC7642
DAC7643
VOUT
+V
OPA2350
+V
100Ω
1000pF
+2.5V
2200pF
VOUT
FIGURE 10. Single-Supply Buffered VREFH.
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +25°C)
LE (LSB)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
DLE (LSB)
DLE (LSB)
LE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
(DAC A, +25°C)
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0000H 2000H 4000H 6000H 8000H A000H C000H E000H FFFFH
Digital Input Code
Digital Input Code
FIGURE 11. Linearity and Differential Linearity Error Curves
for Figure 10.
FIGURE 13. Linearity and Differential Linearity Error Curves
for Figure 12.
DIGITAL INTERFACE
DAC7642
DAC7643
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
VREFH Sense
27
VOUTB Sense
26
VOUTB
25
VOUT
+V
+2.5V
VOUT
See Table I for the basic control logic of the DAC7642 and
DAC7643. Note that each internal register is edge triggered
and not level triggered. When the LOADDACS signal is
transitioned from LOW to HIGH, the digital word existing in
the input register is latched into the DAC register. The first
set of registers (the input registers) are triggered via the
DACSEL, R/W, and CS inputs. Only one of these registers
can be transparent at any given time.
The double-buffered architecture is designed mainly so each
DAC input register can be written to at any time without
affecting the DAC outputs. All DAC voltages are updated
simultaneously by the rising edge of LOADDACS. It also
allows multiple devices to be updated simultaneously by
sharing the LOADDACS control from the host with each
device.
FIGURE 12. Low-Cost Single-Supply Configuration.
16
DAC7642, DAC7643
www.ti.com
SBAS233
DACSEL
R/W
CS
RST
LOADDACS
INPUT
REGISTER
DAC
REGISTER
MODE
DAC
L
H
L
H
X
X
X
L
L
H
H
X
X
X
L
L
L
L
H
H
X
L, H
L, H
L, H
L, H
L, H
L, H
↑
X
X
X
X
↑
L, H
L, H
Write
Write
Read
Read
Hold
Hold
Reset
Hold
Hold
Hold
Hold
Write
Hold
Reset
Write Input
Write Input
Read Input
Read Input
Update
Hold
Reset
A
B
A
B
All
All
All
TABLE I. DAC7642 and DAC7643 Logic Truth Table.
DIGITAL TIMING
VOUT = VREFL +
Figure 14 and Table II provide detailed timing for the digital
interface of the DAC7642 and DAC7643.
(VREFH – VREFL) • N
65, 536
(1)
where N is the digital input code. This equation does not
include the effects of offset (zero-scale) or gain (full-scale)
errors.
DIGITAL INPUT CODING
The DAC7642 and DAC7643 input data is in Straight Binary
format. The output voltage is given by Equation 1:
tWCS
CS
tRCS
CS
tRDH
tRDS
tWS
tWH
tAS
tAH
R/W
DACSEL
R/W
tLS
±0.003% of FSR
Error Band
LOADDACS
DACSEL
tDH
tDS
tDZ
Data In
tS
Data Valid
Data Out
tLH
tLWD
tAH
tAS
tLX
tCSD
VOUT
Data Read Timing
Data Write Timing
±0.003% of FSR
Error Band
tRSH
tRSS
RST
tS
+FS
(DAC7643)
VOUT
Zero-Scale
–FS
+FS
(DAC7642)
VOUT
Midscale
–FS
FIGURE 14. Digital Input and Output Timing.
DAC7642, DAC7643
SBAS233
www.ti.com
17
SYMBOL
DESCRIPTION
MIN
tRCS
tRDS
tRDH
tDZ
tCSD
tWCS
tWS
tWH
tAS
tAH
tLS
tLH
tLX
tDS
tDH
tLWD
tRSS
tRSH
tS
CS LOW for Read
R/W HIGH to CS LOW
R/W HIGH after CS HIGH
CS HIGH to Data Bus in High Impedance
CS LOW to Data Bus Valid
CS LOW for Write
R/W LOW to CS LOW
R/W LOW after CS HIGH
DACSEL Valid to CS LOW
DACSEL Valid after CS HIGH
CS LOW to LOADDACS HIGH
CS LOW after LOADDACS HIGH
LOADDACS HIGH
Data Valid to CS LOW
Data Valid after CS HIGH
LOADDACS LOW
RESET LOW
RESET HIGH
Settling Time
150
10
10
10
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
µs
100
150
100
40
0
10
0
10
30
100
100
0
10
100
10
10
10
TABLE II. Timing Specifications (TA = –40°C to +85°C).
DIGITALLY-PROGRAMMABLE
CURRENT SOURCE
The DAC7642 and DAC7643 offer a unique set of features
that allows a wide range of flexibility in designing applications
circuits, such as programmable current sources. The
DAC7642 and DAC7643 offer both a differential reference
input, as well as an open-loop configuration around the
output amplifier. The open-loop configuration around the
output amplifier allows a transistor to be placed within the
loop to implement a digitally-programmable, unidirectional
current source. The availability of a differential reference also
allows programmability for both the full-scale and zero-scale
currents. The output current is calculated as:
V H – VREFL N Value
IOUT = REF
• 65, 536
R SENSE
+ (VREFL / R SENSE )
Figure 15 shows a DAC7642 and DAC7643 in a 4-20mA
current output configuration. The output current can be
determined by Equation 3:
(3)
IOUT
2.5V – 0.5V N Value 0.5V
=
+
•
65, 536 125Ω
125Ω
At full-scale, the output current is 16mA plus the 4mA for the
zero current. At zero scale the output current is the offset
current of 4mA (0.5V/125Ω).
(2)
IOUT
VPROGRAMMED
125Ω
DAC7642
DAC7643
VOUTA
32
VOUTA Sense
31
VREFL Sense
30
VREFL
29
VREFH
28
OPA2350
100Ω
VREFH Sense
27
26
VOUTB
25
2200pF
20kΩ
1000pF
80kΩ
100Ω
1000pF
VOUTB Sense
+V
2200pF
+V
+2.5V
IOUT
VPROGRAMMED
125Ω
FIGURE 15. 4-20mA Digitally Controlled Current Source.
18
DAC7642, DAC7643
www.ti.com
SBAS233
PACKAGE DRAWING
MTQF002B – JANUARY 1995 – REVISED MAY 2000
VF (S-PQFP-G32)
PLASTIC QUAD FLATPACK
0,45
0,25
0,80
24
0,20 M
17
25
16
32
9
0,13 NOM
1
8
5,60 TYP
7,20
SQ
6,80
9,20
SQ
8,80
Gage Plane
0,05 MIN
0,25
0°– 7°
1,45
1,35
Seating Plane
0,75
0,45
0,10
1,60 MAX
4040172/D 04/00
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
DAC7642, DAC7643
SBAS233
www.ti.com
19
PACKAGE OPTION ADDENDUM
www.ti.com
7-Oct-2021
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)
(4/5)
(6)
DAC7642VFBT
ACTIVE
LQFP
VF
32
250
RoHS & Green
Call TI
Level-1-260C-UNLIM
-40 to 85
DAC7642
B
DAC7642VFT
ACTIVE
LQFP
VF
32
250
RoHS & Green
Call TI
Level-1-260C-UNLIM
-40 to 85
DAC7642
(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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