DAC7715
DAC
771
5
Quad, Serial Input, 12-Bit, Voltage Output
DIGITAL-TO-ANALOG CONVERTER
FEATURES
DESCRIPTION
● LOW POWER: 250mW (max)
● UNIPOLAR OR BIPOLAR OPERATION
● SETTLING TIME: 10µs to 0.012%
The DAC7715 is a quad, serial input, 12-bit, voltage
output Digital-to-Analog Converter (DAC) with
guaranteed 12-bit monotonic performance over the
–40°C to +85°C temperature range. An asynchronous
reset clears all registers to either mid-scale (800H) or
zero-scale (000H), selectable via the RESETSEL pin.
The individual DAC inputs are double buffered to
allow for simultaneous update of all DAC outputs.
The device can be powered from a single +15V supply
or from dual +15V and –15V supplies.
● 12-BIT LINEARITY AND MONOTONICITY:
–40°C to +85°C
● DOUBLE-BUFFERED DATA INPUTS
● SMALL SO-16 PACKAGE
APPLICATIONS
●
●
●
●
●
●
Low power and small size makes the DAC7715 ideal
for automatic test equipment, DAC-per-pin programmers, data acquisition systems, and closed-loop servocontrol. The device is available in a SO-16 package
and is guaranteed over the –40°C to +85°C temperature range.
PROCESS CONTROL
ATE PIN ELECTRONICS
CLOSED-LOOP SERVO-CONTROL
MOTOR CONTROL
DATA ACQUISITION SYSTEMS
DAC-PER-PIN PROGRAMMERS
VCC
GND
VREFH
Input
Register A
DAC
Register A
DAC A
Input
Register B
DAC
Register B
DAC B
Input
Register C
DAC
Register C
DAC C
Input
Register D
DAC
Register D
DAC D
VOUTA
SDI
Serial-toParallel
Shift
Register
CLK
CS
DAC
Select
LOADREG
VOUTB
12
RESETSEL RESET
LOADDACS
VOUTC
VOUTD
VREFL
VSS
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111
Twx: 910-952-1111 • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
http://www.burr-brown.com/
http://www.ti.com/
®
Copyright © 2000 Texas Instruments Incorporated
SBAS140
PDS-1572A
1
Printed in U.S.A. September, 2000
DAC7715
SPECIFICATIONS (Dual Supply)
At TA = –40°C to +85°C, VCC = +15V, VSS = –15V, VREFH = +10V, VREFL = –10V, unless otherwise noted.
DAC7715U
PARAMETER
CONDITIONS
ACCURACY
Linearity Error
Linearity Matching(2)
Differential Linearity Error
Monotonicity
Zero-Scale Error
Zero-Scale Drift
Zero-Scale Matching(2)
Full-Scale Error
Full-Scale Matching(2)
Power Supply Sensitivity
ANALOG OUTPUT
Voltage Output(3)
Output Current
Load Capacitance
Short-Circuit Current
Short-Circuit Duration
DIGITAL INPUT
Logic Levels
VIH
VIL
Data Format
TYP
MAX
MIN
TMIN to TMAX
Code = 000H
±2
At Full Scale
✻
VREFL
–5
VREFH
+5
No Oscillation
✻
✻
To VSS, VCC, or GND
VREFL +1.25
–10
–0.5
–3.5
+10
VREFH – 1.25
3.0
0
8
0.25
2
65
✻
✻
✻
✻
✻
✻
10
V
mA
pF
mA
✻
✻
✻
✻
V
V
mA
mA
✻
µs
LSB
nV-s
nV/√Hz
✻
✻
✻
3.325
✻
1.575
+14.25
–15.75
–40
✻
✻
✻
✻
✻
500
±20
Indefinite
6
–6
180
V
V
✻
Straight Binary
TEMPERATURE RANGE
Specified Performance
LSB(1)
LSB
LSB
Bits
LSB
ppm/°C
LSB
LSB
LSB
ppm/V
±1
✻
±1
10
–8
±1
±1
±1
✻
±2
±2
±2
f = 10kHz
UNITS
✻
Code = FFFH
To ±0.012%, 20V Output Step
Full-Scale Step
MAX
✻
12
1
IIH ≤ ±10µA
IIL ≤ ±10µA
POWER SUPPLY REQUIREMENTS
VCC
VSS
ICC
ISS
Power Dissipation
TYP
±2
±2
±1
REFERENCE INPUT
VREFH Input Range
VREFL Input Range
Ref High Input Current
Ref Low Input Current
DYNAMIC PERFORMANCE
Settling Time
Channel-to-Channel Crosstalk
Digital Feedthrough
Output Noise Voltage
MIN
DAC7715UB
+15.75
–14.25
8.5
✻
✻
✻
250
+85
✻
✻
✻
✻
✻
✻
✻
✻
V
V
mA
mA
mW
✻
°C
NOTES: (1) LSB means Least Significant Bit; if VREFH equals +10V and VREFL equals –10V, then one LSB equals 4.88mV. (2) All DAC outputs will match within
the specified error band. (3) Ideal output voltage does not take into account zero or full-scale error.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.
®
DAC7715
2
SPECIFICATIONS (Single Supply)
At TA = –40°C to +85°C, VCC = +15V, VSS = GND, VREFH = +10V, VREFL = 0V, unless otherwise noted.
DAC7715U
PARAMETER
ACCURACY
Linearity Error(1)
Linearity Matching(3)
Differential Linearity Error
Monotonicity
Zero-Scale Error
Zero-Scale Drift
Zero-Scale Matching(3)
Full-Scale Error
Full-Scale Matching(3)
Power Supply Sensitivity
ANALOG OUTPUT
Voltage Output(4)
Output Current
Load Capacitance
Short-Circuit Current
Short-Circuit Duration
CONDITIONS
DIGITAL INPUT
Logic Levels
VIH
VIL
Data Format
POWER SUPPLY REQUIREMENTS
VCC
ICC
Power Dissipation
TEMPERATURE RANGE
Specified Performance
TYP
MAX
MIN
TYP
±2
±2
±1
TMIN to TMAX
Code = 004H
±4
At Full Scale
✻
VREFH
+5
No Oscillation
✻
✻
To VCC or GND
VREFL +1.25
0
–0.3
–2.0
✻
V
mA
pF
mA
✻
✻
✻
✻
V
V
mA
mA
✻
µs
LSB
nV-s
nV/√Hz
✻
✻
✻
500
±20
Indefinite
+10
VREFH – 1.25
1.5
0
8
0.25
2
65
✻
✻
✻
✻
✻
✻
10
✻
✻
✻
3.325
✻
1.575
14.25
V
V
✻
Straight Binary
15.75
✻
✻
✻
3.0
45
–40
LSB(2)
LSB
LSB
Bits
LSB
ppm/°C
LSB
LSB
LSB
ppm /V
±2
✻
±2
20
VREFL
–5
IIH ≤ ±10µA
IIL ≤ ±10µA
±1
±1
±1
✻
±4
±4
±4
f = 10kHz
UNITS
✻
Code = FFFH
To ±0.012%, 10V Output Step
MAX
✻
12
2
REFERENCE INPUT
VREFH Input Range
VREFL Input Range
Ref High Input Current
Ref Low Input Current
DYNAMIC PERFORMANCE
Settling Time(5)
Channel-to-Channel Crosstalk
Digital Feedthrough
Output Noise Voltage
MIN
DAC7715UB
+85
✻
✻
✻
V
mA
mW
✻
°C
NOTES: (1) If VSS = 0V, specification applies at code 004H and above. (2) LSB means Least Significant Bit; if VREFH equals +10V and VREFL equals 0V, then one
LSB equals 2.44mV. (3) All DAC outputs will match within the specified error band. (4) Ideal output voltage does not take into account zero or full-scale error.
(5) Full-scale positive 10V step and negative step from code FFFH to 020H.
®
3
DAC7715
ELECTROSTATIC
DISCHARGE SENSITIVITY
ABSOLUTE MAXIMUM RATINGS(1)
VCC to VSS ........................................................................... –0.3V to +32V
VCC to GND ......................................................................... –0.3V to +16V
VSS to GND ......................................................................... +0.3V to –16V
VREFH to GND ....................................................................... –9V to +11V
VREFL to GND (VSS = –15V) ................................................. –11V to +9V
VREFL to GND (VSS = 0V) .................................................... –0.3V to +9V
VREFH to VREFL ....................................................................... –1V to +22V
Digital Input Voltage to GND .............................................. –0.3V to 5.8V
Digital Output Voltage to GND ............................................ –0.3V to 5.8V
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ........................................ –40°C to +85°C
Storage Temperature Range ......................................... –65°C to +150°C
Lead Temperature (soldering, 10s) ............................................... +300°C
This integrated circuit can be damaged by ESD. Burr-Brown
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
MAXIMUM
LINEARITY
ERROR
(LSB)
MAXIMUM
DIFFERENTIAL
LINEARITY
(LSB)
DAC7715U
PACKAGE
PACKAGE
DRAWING
NUMBER
SPECIFICATION
TEMPERATURE
RANGE
±2
±1
SOIC-16
211
–40°C to +85°C
"
"
"
"
"
"
DAC7715UB
±1
±1
SOIC-16
211
–40°C to +85°C
"
"
"
"
"
"
ORDERING
NUMBER(1)
TRANSPORT
MEDIA
DAC7715U
DAC7715U/1K
DAC7715UB
DAC7715UB/1K
Rails
Tape and Reel
Rails
Tape and Reel
NOTE: (1) Models with a slash (/) are available only in Tape and Reel in the quantities indicated (e.g., /1K indicates 1000 devices per reel). Ordering 1000 pieces
of “DAC7715UB/1K” will get a single 1000-piece Tape and Reel.
ESD PROTECTION CIRCUITS
VCC
VCC
REFH
VOUT
REFL
VSS
VSS
Internal VDD
GND
Typical of Each
Logic Input Pin
®
DAC7715
4
PIN CONFIGURATION—U Package
PIN DESCRIPTIONS—U Package
Top View
PIN
SOIC
VCC
16
1
15
RESETSEL
LABEL
DESCRIPTION
Positive Supply Voltage, +15V nominal.
1
VCC
2
VOUTD
DAC D Voltage Output
3
VOUTC
DAC C Voltage Output
4
VREFL
Reference Input Voltage Low. Sets minimum output voltage for all DACs.
5
VREFH
Reference Input Voltage High. Sets maximum output voltage for all DACs.
6
VOUTB
DAC B Voltage Output
7
VOUTA
DAC A Voltage Output
8
VSS
VOUTD
2
VOUTC
3
14
LOADREG
9
GND
VREFL
4
13
LOADDACS
10
SDI
Serial Data Input
11
CLK
Serial Data Clock
DAC7715U
RESET
12
CS
6
11
CLK
VOUTA
7
10
SDI
VSS
8
9
GND
VREFH
5
VOUTB
Negative Supply Voltage, 0V or –15V nominal.
Ground
12
CS
13
LOADDACS
All DAC registers become transparent when
LOADDACS is LOW. They are in the latched state
when LOADDACS is HIGH.
Chip Select Input
14
LOADREG
The selected input register becomes transparent
when LOADREG is LOW. It is in the latched state
when LOADREG is HIGH.
15
RESET
Asynchronous Reset Input. Sets DAC and input
registers to either zero-scale (000H) or mid-scale
(800H) when LOW. RESETSEL determines which
code is active.
16
RESETSEL
When LOW, a LOW on RESET will cause the DAC
and input registers to be set to code 000H. When
RESETSEL is HIGH, a LOW on RESET will set the
registers to code 800H.
®
5
DAC7715
TYPICAL PERFORMANCE CURVES: VSS = 0V
At TA = +25°C, VCC = +15V, VSS = 0V, VREFH = +10V, VREFL = 0V, representative unit, unless otherwise specified.
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
Single Channel 85°C
(Typical of Each Output Channel)
DLE (LSB)
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
000H
LE (LSB)
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
200H
400H
600H
800H
A00H
C00H
E00H
FFFH
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
000H
200H
400H
800H
A00H
C00H
E00H
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
Single Channel –40°C
(Typical of Each Output Channel)
ZERO-SCALE ERROR vs TEMPERATURE
(Code 004H)
FFFH
2.0
1.5
DAC D
1.0
DAC A
0.5
0
–0.5
DAC B
DAC C
–1.0
–1.5
–2.0
200H
400H
600H
800H
A00H
C00H
E00H
–40 –30 –20 –10 0
FFFH
CURRENT vs CODE
All DACs Set to Indicated Code
FULL-SCALE ERROR vs TEMPERATURE
(Code FFFH)
VREFH
VREF Current (mA)
2.0
1.5
1.0
DAC D
10 20 30 40 50 60 70 80 90
Temperature (°C)
Digital Input Code
DAC B
0.5
1.2
1.0
0.8
0.6
0.4
0.2
0
–0.2
–0.4
VREFL
0
VREF Current (mA)
Full-Scale Error (mV)
600H
Digital Input Code
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
000H
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
Digital Input Code
Zero-Scale Error (mV)
DLE (LSB)
LE (LSB)
DLE (LSB)
LE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
Single Channel 25°C
(Typical of Each Output Channel)
–0.5
DAC A
DAC C
–1.0
–1.5
–2.0
–40 –30 –20 –10 0
10 20 30 40 50 60 70 80 90
Temperature (°C)
200H
400H
600H
800H
A00H
Digital Input Code
®
DAC7715
0
–0.2
–0.4
–0.6
–0.8
–1.0
–1.2
–1.4
–1.6
000H
6
C00H
E00H
FFFH
TYPICAL PERFORMANCE CURVES: VSS = 0V
(Cont.)
At TA = +25°C, VCC = +15V, VSS = 0V, VREFH = +10V, VREFL = 0V, representative unit, unless otherwise specified.
POSITIVE SUPPLY CURRENT
vs DIGITAL INPUT CODE
POWER SUPPLY CURRENT vs TEMPERATURE
6.00
ICC
3.5
5.00
No Load, All DACs Set to Indicated Code
4.00
ICC (mA)
2.5
1.5
ICC
3.00
2.00
0.5
1.00
0
–40 –30 –20 –10 0
0
000H
10 20 30 40 50 60 70 80 90 100
400H
600H
800H
A00H C00H E00H FFFH
Digital Input Code
OUTPUT VOLTAGE vs SETTLING TIME
(0V to +10V)
OUTPUT VOLTAGE vs SETTLING TIME
(+10V to Code 020H)
Large Signal
Settling Time: 5V/div
Output Voltage
Output Voltage
200H
Temperature (°C)
Large Signal
Settling Time: 5V/div
Small Signal
Settling Time: 1LSB/div
Small Signal
Settling Time: 1LSB/div
+5V
LOADDACS
0
+5V
LOADDACS
0
Time (2µs/div)
Time (2µs/div)
OUTPUT VOLTAGE
MID-SCALE GLITCH PERFORMANCE
OUTPUT VOLTAGE
MID-SCALE GLITCH PERFORMANCE
7FFH to 800H
+5V
LOADDACS
0
Time (1µs/div)
Output Voltage (200mV/div)
Output Voltage (200mV/div)
Quiescent Current (mA)
4.5
800H to 7FFH
+5V
LOADDACS
0
Time (1µs/div)
®
7
DAC7715
TYPICAL PERFORMANCE CURVES: VSS = 0V
(Cont.)
At TA = +25°C, VCC = +15V, VSS = 0V, VREFH = +10V, VREFL = 0V, representative unit, unless otherwise specified.
OUTPUT VOLTAGE vs RLOAD
OUTPUT NOISE vs FREQUENCY
15
1000
12
Source
VOUT (V)
Noise (nV/√Hz)
Code 020H
100
Code FFFH
9
6
3
Sink
0
0.01
10
0
0.1
1
10
100
Frequency (kHz)
1000
10000
Short to Ground
PSRR (dB)
IOUT (mA)
5
0
–5
–10
Short to VCC
200H
400H
600H
800H
A00H C00H
–40
–50
–60
–70
–80
–90
–100
–110
–120
+15V
101
E00H FFFH
102
103
104
Frequency (Hz)
Digital Input Code
®
DAC7715
100
0
–10
–20
–30
10
–20
000H
10
POWER SUPPLY REJECTION RATIO vs FREQUENCY
SINGLE SUPPLY CURRENT LIMIT vs INPUT CODE
–15
1
RLOAD (kW)
20
15
0.1
8
105
106
TYPICAL PERFORMANCE CURVES: VSS = –15V
At TA = +25°C, VCC = +15V, VSS = 0V, VREFH = +10V, VREFL = 0V, representative unit, unless otherwise specified.
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
Single Channel 85°C
(Typical of Each Output Channel)
DLE (LSB)
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
000H
LE (LSB)
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
200H
400H
600H
800H
A00H
C00H
E00H
FFFH
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
000H
200H
400H
600H
800H
A00H
C00H
Digital Input Code
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
Single Channel –40°C
(Typical of Each Output Channel)
CURRENT vs CODE
All DACs Set to Indicated Code
VREF Current (mA)
VREF Current (mA)
200H
400H
600H
800H
A00H
C00H
E00H
E00H
FFFH
2.5
2.0
1.5
1.0
0.5
0
–0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
000H
VREFL
200H
400H
600H
800H
A00H
C00H
E000H FFFH
Digital Input Code
Digital Input Code
BIPOLAR ZERO-SCALE ERROR vs TEMPERATURE
(Code 800H)
POSITIVE FULL-SCALE ERROR vs TEMPERATURE
(Code FFFH)
2.0
2.0
1.5
1.5
1.0
DAC A
DAC D
0.5
0
–0.5
–1.0
DAC D
FFFH
VREFH
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
000H
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
Digital Input Code
Positive Full-Scale Error (mV)
Bipolar Zero-Scale Error (mV)
DLE (LSB)
LE (LSB)
DLE (LSB)
LE (LSB)
LINEARITY ERROR AND
DIFFERENTIAL LINEARITY ERROR vs CODE
Single Channel 25°C
(Typical of Each Output Channel)
DAC C
–1.5
–2.0
1.0
DAC D
DAC B
0.5
0
–0.5
DAC A
–1.0
DAC C
–1.5
–2.0
–40 –30 –20 –10 0
10 20 30 40 50 60 70 80 90
–40 –30 –20 –10 0
Temperature (°C)
10 20 30 40 50 60 70 80 90
Temperature (°C)
®
9
DAC7715
TYPICAL PERFORMANCE CURVES: VSS = –15V
(Cont.)
At TA = +25°C, VCC = +15V, VSS = 0V, VREFH = +10V, VREFL = 0V, representative unit, unless otherwise specified.
POWER SUPPLY CURRENT vs TEMPERATURE
2.0
8
1.5
6
Quiescent Current (mA)
Negative Full-Scale Error (mV)
NEGATIVE FULL-SCALE ERROR vs TEMPERATURE
(Code 000H)
1.0
DAC D
0.5
0
–0.5
DAC B
DAC A
DAC C
–1.0
–1.5
4
2
0
–2
ISS
–4
–6
–2.0
–8
–40 –30 –20 –10 0
–40 –30 –20 –10 0
10 20 30 40 50 60 70 80 90
10 20 30 40 50 60 70 80 90
Temperature (°C)
Temperature (°C)
OUTPUT VOLTAGE vs RLOAD
SUPPLY CURRENT vs CODE
8
15
ICC
6
10
Supply Current (mA)
Source
5
0
–5
Sink
–10
4
No Load, All 4 DACs Set to Indicated Code
2
0
–2
–4
ISS
–6
–15
0.01
0.1
1
10
–8
000H
100
200H
400H
600H
800H
A00H C00H
RLOAD (kΩ)
Digital Input Code
OUTPUT VOLTAGE vs SETTLING TIME
(–10V to +10V)
OUTPUT VOLTAGE vs SETTLING TIME
(+10V to –10V)
Output Voltage
Small Signal
Settling Time: 0.5LSB/div
Small Signal
Settling Time: 0.5LSB/div
+5V
LOADDACS
0
Time (2µs/div)
+5V
LOADDACS
0
Time (2µs/div)
®
DAC7715
E00H FFFH
Large Signal
Settling Time: 5V/div
Large Signal
Settling Time: 5V/div
Output Voltage
VOUT (V)
ICC
Data = FFFH (all DACs)
No Load
10
TYPICAL PERFORMANCE CURVES: VSS = –15V
(Cont.)
At TA = +25°C, VCC = +15V, VSS = 0V, VREFH = +10V, VREFL = 0V, representative unit, unless otherwise specified.
DUAL SUPPLY CURRENT LIMIT vs INPUT CODE
SHORT TO GROUND
POWER SUPPLY REJECTION RATIO vs FREQUENCY
20
15
5
PSRR (dB)
IOUT (mA)
10
0
–5
–10
+15V
400H
600H
800H
A00H C00H
101
E00H FFFH
102
103
104
Digital Input Code
Frequency (Hz)
OUTPUT VOLTAGE
MID-SCALE GLITCH PERFORMANCE
BROADBAND NOISE
7FFH to 800H
105
106
Noise Voltage (500µV/div)
200H
800H to 7FFH
+5V
LOADDACS
0
Time (1ms/div)
Time (1µs/div)
OUTPUT NOISE vs FREQUENCY
1000
Noise (nV/√Hz)
Output Voltage (200mV/div)
–15V
–100
–110
–120
–15
–20
000H
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
100
Noise at any code
10
0
0.1
1
10
100
Frequency (kHz)
1000
10000
®
11
DAC7715
THEORY OF OPERATION
digital input is a 16-bit serial word that contains the 12-bit
DAC code and a 2-bit address code that selects one of the four
DACs (the two remaining bits are unused). The converter can
be powered from a single +15V supply or a dual ±15V
supply. Each device offers a reset function which immediately sets all DAC output voltages and internal registers to
either zero-scale (code 000H) or mid-scale (code 800H). The
reset code is selected by the state of the RESETSEL pin
(LOW = 000H, HIGH = 800H). See Figures 2 and 3 for the
basic operation of the DAC7715.
The DAC7715 is a quad, serial input, 12-bit, voltage output
DAC. The architecture is a classic R-2R ladder configuration
followed by an operational amplifier that serves as a buffer,
as shown in Figure 1. Each DAC has its own R-2R ladder
network and output op amp, but all share the reference
voltage inputs. The minimum voltage output (“zero-scale”)
and maximum voltage output (“full-scale”) are set by external
voltage references (VREFL and VREFH, respectively). The
RF
R
R
2R
2R
2R
R
R
2R
R
2R
R
2R
VOUT
R
2R
2R
2R
VREFH
VREFL
FIGURE 1. DAC7715 Architecture.
+15V
+
1µF to 10µF
DAC7715
0.1µF
0V to +10V
0V to +10V
1
VCC
RESETSEL
16
2
VOUTD
RESET
15
Reset DACs(1)
3
VOUTC
LOADREG
14
Update Selected Register
4
VREFL
LOADDACS
13
Update All DAC Registers
5
VREFH
CS
12
Chip Select
6
VOUTB
CLK
11
Clock
7
VOUTA
SDI
10
Serial Data In
8
VSS
GND
9
+10.00V
0.1µF
0V to +10V
0V to +10V
NOTE: (1) As configured, RESET LOW sets all internal registers to code 000H (0V).
If RESETSEL is HIGH, RESET LOW sets all internal registers to code 800H (5.00V).
FIGURE 2. Basic Single-Supply Operation of the DAC7715.
+15V
DAC7715
+
1µF to 10µF
0.1µF
1
VCC
–10V to +10V
2
–10V to +10V
–10.00V
16
VOUTD
RESET
15
Reset DACs(1)
3
VOUTC
LOADREG
14
Update Selected Register
4
VREFL
LOADDACS
13
Update All DAC Registers
5
VREFH
CS
12
Chip Select
6
VOUTB
CLK
11
Clock
7
VOUTA
SDI
10
Serial Data In
8
VSS
GND
9
0.1µF
+10.00V
0.1µF
–10V to +10V
–10V to +10V
+5V
RESETSEL
–15V
+
1µF to 10µF
0.1µF
NOTE: (1) As configured, RESET LOW sets all internal registers to code 800H (0V).
If RESETSEL is LOW, RESET LOW sets all internal registers to code 000H (–10 V).
FIGURE 3. Basic Dual-Supply Operation of the DAC7715.
®
DAC7715
12
ANALOG OUTPUTS
approximately 3mA. The reference input appears as a varying load to the reference. If the reference can sink or source
the required current, a reference buffer is not required. See
“Reference Current vs Code” in the Typical Performance
Curves.
The analog supplies must come up before the reference
power supplies, if they are separate. If the power supplies for
the references come up first, then the VCC and VSS supplies
will be powered from the reference via the ESD protection
diodes (see page 4).
When VSS = –15V (dual supply operation), the output
amplifier can swing to within 4V of the supply rails, over
the –40°C to +85°C temperature range. With VSS = 0V
(single-supply operation), the output can swing to ground.
Note that the settling time of the output op amp will be
longer with voltages very near ground. Also, care must be
taken when measuring the zero-scale error when VSS = 0V.
If the output amplifier has a negative offset, the output
voltage may not change for the first few digital input codes
(000H, 001H, 002H, etc.) since the output voltage cannot
swing below ground.
At the negative offset limit of –4LSB (–9.76mV), for the
single-supply case, the first specified output starts at code
004H.
DIGITAL INTERFACE
Figure 4 and Table I provide the basic timing for the
DAC7715. The interface consists of a serial clock (CLK),
serial data (SDI), a load register signal (LOADREG), and a
REFERENCE INPUTS
SYMBOL
The reference inputs, VREFL and VREFH, can be any voltage
between VSS + 4V and VCC – 4V provided that VREFH is at
least 1.25V greater than VREFL. The minimum output of
each DAC is equal to VREFL – 1LSB 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 that VSS (the negative power supply) must
either be connected to ground or be in the range of –14.75V
to –15.25V. 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 is not guaranteed.
The current into the reference inputs depends on the DAC
output voltages and can vary from a few microamps to
tDS
tDH
tCH
tCL
tCSS
tCSH
tLD1
tLD2
tLDRW
tLDDW
tRSSH
tRSTW
tS
DESCRIPTION
MIN
Data Valid to CLK Rising
Data Held Valid after CLK Rises
CLK HIGH
CLK LOW
CS LOW to CLK Rising
CLK HIGH to CS Rising
LOADREG HIGH to CLK Rising
CLK Rising to LOADREG LOW
LOADREG LOW Time
LOADDACS LOW Time
RESETSEL Valid to RESET LOW
RESET LOW Time
Settling Time
25
20
30
50
55
15
40
15
45
45
25
70
10
A1
A0
X
X
D11
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
µs
TABLE I. Timing Specifications (TA = –40°C to +85°C).
(MSB)
SDI
TYP
(LSB)
D10
D9
D3
D2
D1
D0
CLK
tcss
tCSH
tLD1
tLD2
CS
LOADREG
tLDRW
tDS
tDH
SDI
tCL
tCH
CLK
tLDDW
LOADDACS
tS
VOUT
tS
1 LSB
ERROR BAND
1 LSB
ERROR BAND
tRSTW
RESET
tRSSH
RESETSEL
FIGURE 4. DAC7715 Timing.
®
13
DAC7715
STATE OF
SELECTED
INPUT
REGISTER
STATE OF
ALL DAC
REGISTERS
A1
A0
LOADREG
LOADDACS
RESET
SELECTED
INPUT
REGISTER
L(1)
L
L
H(2)
H
A
Transparent
Latched
L
H
L
H
H
B
Transparent
Latched
H
L
L
H
H
C
Transparent
Latched
H
H
L
H
H
D
Transparent
Latched
X(3)
X
H
L
H
NONE
(All Latched)
Transparent
X
X
H
H
H
NONE
(All Latched)
Latched
X
X
X
X
L
ALL
Reset(4)
Reset(4)
NOTES: (1) L = Logic LOW. (2) H = Logic HIGH. (3) X = Don’t Care. (4) Resets to either 000H or 800H, per the RESETSEL state (LOW = 000H, HIGH = 800H).
When RESET rises, all registers that are in their latched state retain the reset value.
TABLE II. Control Logic Truth Table.
CS(1)
CLK(1)
H(2)
X(3)
H
H
No Change
L(4)
L
H
H
No Change
LOADREG
RESET
CLK when CS rises at the end of a serial transfer. If CLK is
LOW when CS rises, the OR gate will provide a rising edge
to the shift register, shifting the internal data one additional
bit. The result will be incorrect data and possible selection of
the wrong input register.
SERIAL SHIFT REGISTER
L
↑(5)
H
H
Advanced One Bit
↑
L
H
H
Advanced One Bit
H(6)
X
L(7)
H
No Change
H(6)
X
H
L(8)
No Change
If both CS and CLK are used, then CS should rise only when
CLK is HIGH. If not, then either CS or CLK can be used to
operate the shift register. See Table III for more information.
NOTES: (1) CS and CLK are interchangeable. (2) H = Logic HIGH.
(3) X = Don’t Care. (4) L = Logic LOW (5) = Positive Logic Transition.
(6) A HIGH value is suggested in order to avoid a “false clock” from
advancing the shift register and changing the shift register. (7) If data is
clocked into the serial register while LOADREG is LOW, the selected input
register will change as the shift register bits “flow” through A1 and A0. This
will corrupt the data in each input register that has been erroneously
selected. (8) RESET LOW causes no change in the contents of the serial
shift register.
The digital data into the DAC7715 is double-buffered. This
allows new data to be entered for each DAC without disturbing the analog outputs. When the new settings have been
entered into the device, all of the DAC outputs can be
updated simultaneously. The transfer from the input registers to the DAC registers is accomplished with a HIGH to
LOW transition on the LOADDACS input.
TABLE III. Serial Shift Register Truth Table.
Because the DAC registers become transparent when
LOADDACS is LOW, it is possible to keep this pin LOW
and update each DAC via LOADREG. However, as each
new data word is entered into the device, the corresponding
output will update immediately when LOADREG is taken
LOW.
“load all DAC registers” signal (LOADDACS). In addition,
a chip select (CS) input is available to enable serial communication when there are multiple serial devices. An asynchronous reset input (RESET) is provided to simplify startup conditions, periodic resets, or emergency resets to a
known state.
Digital Input Coding
The DAC code and address are provided via a 16-bit serial
interface as shown in Figure 4. The first two bits select the
input register that will be updated when LOADREG goes
LOW, as shown in Table II. The next two bits are not used.
The last 12 bits are the DAC code which is provided, most
significant bit first.
The DAC7715 input data is in Straight Binary format. The
output voltage is given by the following equation:
VOUT = VREFL +
Note that CS and CLK are combined with an OR gate and
the output controls the serial-to-parallel shift register internal to the DAC7715 (see the block diagram on the front of
this data sheet). These two inputs are completely interchangeable. In addition, care must be taken with the state of
where N is the digital input code (in decimal). This equation
does not include the effects of offset (zero-scale) or gain
(full-scale) errors.
®
DAC7715
(VREFH – VREFL ) • N
4096
14
LAYOUT
be separate from the ground connection for the digital
components until they were connected at the power entry
point of the system.
A precision analog component requires careful layout, adequate bypassing, and clean, well-regulated power supplies.
As the DAC7715 offers single-supply operation, 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 difficult it will be to achieve good
performance from the converter.
The power applied to VDD (as well as VSS, if not grounded)
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.
Because the DAC7715 has a single ground pin, all return
currents, including digital and analog return currents, must
flow through the GND pin. Ideally, GND would be connected directly to an analog ground plane. This plane would
®
15
DAC7715
PACKAGE OPTION ADDENDUM
www.ti.com
20-Aug-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)
DAC7715U
ACTIVE
SOIC
DW
16
40
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC7715U
DAC7715U/1K
ACTIVE
SOIC
DW
16
1000
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC7715U
DAC7715UB
ACTIVE
SOIC
DW
16
40
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC7715U
B
DAC7715UB/1K
ACTIVE
SOIC
DW
16
1000
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC7715U
B
DAC7715UG4
ACTIVE
SOIC
DW
16
40
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC7715U
(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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