Burr Brown Products
from Texas Instruments
DA
C7
8
22
DAC7822
SBAS374 – JUNE 2006
Dual, 12-Bit, Parallel Input, Multiplying
Digital-to-Analog Converter
FEATURES
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±1LSB
INL
2.5V to 5.5V Supply Operation
Fast Parallel Interface:
17ns Write Cycle
Update Rate of 20.4MSPS
10MHz Multiplying Bandwidth
±15V
Reference Input
Extended Temperature Range:
–40°C to +125°C
40-Lead QFN
12-Bit Monotonic
4-Quadrant Multiplication
Power-On Reset with Brownout Detection
Readback Function
Industry-Standard Pin Configuration
Pin-Compatible with the AD5405
DESCRIPTION
The DAC7822 is a dual, CMOS, 12-bit, current
output digital-to-analog converter (DAC). This device
operates from a 2.5V to 5.5V power supply, making it
suitable for battery-powered and many other
applications.
The DAC7822 operates with a fast parallel interface.
Data readback allows the user to read the contents
of the DAC register via the DB pins. On power-up,
the internal register and latches are filled with zeroes
and the DAC outputs are at zero scale.
The
DAC7822
offers
excellent
4-quadrant
multiplication characteristics, with large signal
multiplying bandwidth of 10MHz. The applied
external reference input voltage (V
REF
) determines
the full-scale output current. An integrated feedback
resistor (R
FB
) provides temperature tracking and
full-scale voltage output when combined with an
external current-to-voltage precision amplifier. The
DAC7822 also includes the resistors necessary for
4-quadrant multiplication and other configuration
modes.
The DAC7822 is available in a 40-lead QFN
package.
R
3
A
R
3
2R
V
DD
DB0
DB11
INPUT
BUFFER
LATCH
12-Bit
R-2R DAC A
I
OUT
1A
I
OUT
2A
R
2_3
A
R
2
2R
R
2
A V
REF
A
R
1
A
R
1
2R
R
FB
2R
R
FB
A
DATA
INPUTS
APPLICATIONS
Portable Battery-Powered Instruments
Waveform Generators
Analog Processing
Programmable Amplifiers and Attenuators
Digitally-Controlled Calibration
Programmable Filters and Oscillators
Ultrasound
DAC
A
/B
CS
R/W
LDAC
CLR
GND
POWER-ON
RESET
R
3
2R
R
2
2R
R
1
2R
R
FB
2R
R
FB
B
CONTROL
LOGIC
LATCH
12-Bit
R-2R DAC B
I
OUT
1B
I
OUT
2B
R
3
B
R
2_3
B
R
2
B V
REF
B
R
1
B
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.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2006, Texas Instruments Incorporated
DAC7822
www.ti.com
SBAS374 – JUNE 2006
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.
ORDERING INFORMATION
(1)
PACKAGE
DESIGNATOR
RTA
SPECIFIED
TEMPERATURE
RANGE
–40°C to +125°C
PACKAGE
MARKING
DAC7822
ORDERING
NUMBER
DAC7822IRTAT
DAC7822IRTAR
TRANSPORT MEDIA,
QUANTITY
250, Tape and Reel
2000, Tape and Reel
PRODUCT
DAC7822
(1)
PACKAGE
40-QFN
For the most current specifications and package information, see the Package Option Addendum at the end of this data sheet, or refer
to our web site at
www.ti.com.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted)
(1)
DAC7822
V
DD
to GND
Digital input voltage to GND
V
OUT
to GND
Operating temperature range
Storage temperature range
Junction temperature (T
J
max)
ESD Rating, HBM
ESD Rating, CDM
(1)
–0.3 to +7.0
–0.3 to V
DD
+ 0.3
–0.3 to V
DD
+ 0.3
–40 to +125
–65 to +150
+150
2000
1000
UNIT
V
V
V
°C
°C
°C
V
V
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.
2
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DAC7822
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SBAS374 – JUNE 2006
ELECTRICAL CHARACTERISTICS
V
DD
= +2.5V to +5.5V; I
OUT
1 = Virtual GND; I
OUT
2 = 0V; V
REF
= 10V; T
A
= full operating temperature. All specifications –40°C
to +125°C, unless otherwise noted.
DAC7822
PARAMETER
STATIC PERFORMANCE
Resolution
Relative accuracy
Differential nonlinearity
Output leakage current
Output leakage current
Full-scale gain error
Full-scale
tempco
(1)
Circuit configuration as shown in
Figure 41
DAC latches leaded with all 1s
–15
8
17
17
10
20
20
1.6
0.06
V
DD
= +2.5V
V
DD
= +5V
V
DD
= +2.5V
V
DD
= +5V
2.1
2.4
1
10
2.5
Logic inputs = 0V
V
IH
= V
DD
and V
IL
= GND
V
IH
= V
DD
and V
IL
= GND
0.8
0.4
5.5
5
5
2.5
0.2
V
REF
= 7V
PP
, Data = FFFh
V
REF
= 0V to 10V,
Data = 7FFh to 800h to 7FFh
Data = 000h, V
REF
= 100kHz
10
10
–70
2
–105
25
25
Bipolar zero-code error
Output capacitance
REFERENCE INPUT
V
REF
range
V
REF
A, V
REF
B, Input resistance
R
1
, R
FB
resistance
R
2
, R
3
resistance
V
REF
A to V
REF
B Input Mismatch
R
2
to R
3
Mismatch
LOGIC INPUTS AND OUTPUT
(1)
Input low voltage
Input high voltage
Input leakage current
Input capacitance
POWER REQUIREMENTS
V
DD
I
DD
(normal operation)
V
DD
= +4.5V to +5.5V
V
DD
= +2.5V to +3.6V
AC CHARACTERISTICS
(1)
Output voltage settling time
Reference multiplying BW
DAC glitch impulse
Feedthrough error V
OUT
/V
REF
Digital feedthrough
Total harmonic distortion
Output spot noise voltage
(1)
Specified by design and characterization; not production tested.
µs
MHz
nV-s
dB
nV-s
dB
nV/√Hz
V
µA
µA
µA
V
IL
V
IH
I
IL
C
IL
0.6
0.8
V
V
V
V
µA
pF
15
12
25
25
2.5
0.18
V
kΩ
kΩ
kΩ
%
%
Data = 000h, T
A
= +25°C
Data = 000h, T
A
= T
MAX
All ones loaded to DAC register
±10
±5
±25
30
12
±1
±1
±1
±15
±25
Bits
LSB
LSB
nA
nA
mV
ppm/°C
mV
pF
CONDITIONS
MIN
TYP
MAX
UNITS
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3
DAC7822
www.ti.com
SBAS374 – JUNE 2006
TIMING INFORMATION
t
1
R/W
t
9
CS
t
3
t
5
t
2
t
8
t
2
t
4
DACA/DACB
t
6
t
10
t
11
t
7
DATA
DATA VALID
t
12
t
13
DATA VALID
TIMING REQUIREMENTS: 2.5 V to 5.5 V
At t
r
= t
f
= 1ns (10% to 90% of V
DD
) and timed from a voltage level of (V
IL
+ V
IH
)/2; V
DD
= 2.5V to 5.5V, V
REF
= 10V,
I
OUT
2 = 0V. All specifications –40°C to +125°C, unless otherwise noted.
DAC7822
PARAMETER
(1)
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
t
11
t
12
t
13
(1)
TEST CONDITIONS
R/W to CS setup time
R/W to CS hold time
CS low time (write cycle)
Address setup time
Address hold time
Data setup time
Data hold time
R/W high to CS low
CS minimum high time
Address setup time (Read Cycle)
Address hold time (Read Cycle)
Data access time
Bus relinquish time
MIN
0
0
10
10
0
6
0
5
7
0
0
5
5
35
10
TYP
MAX
UNIT
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Ensured by design; not production tested.
4
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SBAS374 – JUNE 2006
DEVICE INFORMATION
I
OUT
2A
I
OUT
1A
I
OUT
1B
I
OUT
2B
32
R
FB
A
NC
39
36
34
NC
33
40
38
31
37
35
R
FB
B
30
29
28
27
NC
NC
R
1
A
R
2
A
R
2_3
A
R
3
A
V
REF
A
DGND
LDAC
DAC A/B
NC
DB11
1
2
3
4
5
6
7
8
9
10
R
1
B
R
2
B
R
2_3
B
R
3
B
V
REF
B
V
DD
CLR
R/W
CS
DB0
DAC7822
26
25
24
23
22
21
12
15
17
18
19
11
DB9
DB8
13
DB10
TERMINAL FUNCTIONS
PIN NO.
1-4
5, 26
6
7
8
9, 34-37
10-21
22
23
24
25
27-30
31, 40
32
33
38
39
PIN NAME
R
1
A, R
2
A, R
2_3
A, R
3
A
V
REF
A, V
REF
B
DGND
LDAC
DAC A/B
NC
DB11 to DB0
CS
R/W
CLR
V
DD
R
3
B, R
2_3
B, R
2
B, R
1
B
R
FB
B, R
FB
A
I
OUT
2B
I
OUT
1B
I
OUT
1A
I
OUT
2A
DESCRIPTION
DAC A 4-Quadrant Resistors. Allows a number of configuration modes, including bipolar operation with
minimum of external components.
DAC Reference Voltage Input Terminals.
Digital Ground Pin.
Load DAC Input. Allows asynchronous or synchronous updates to the DAC output. The DAC is asynchronously
updated when this signal goes low. Alternatively, if this line is held permanently low, an automatic or
synchronous update mode is selected whereby the DAC is updated on the rising edge of CS.
Selects DAC A or B. Low selects DAC A, and high selects DAC B.
Not internally connected.
Parallel Data Bits 11 through 0.
Chip Select Input; active low. Used in conjuction with R/W to load parallel data to the input latch or to read data
from the DAC register. Edge sensitive; when pulled high, the DAC data is latched.
Read/Write. When low, used in conjunction with CS to load parallel data. When high, used in conjunction with
CS to read back contents of DAC register.
Active Low Control Input. Clears DAC output and input and DAC registers.
Positive Power Supply Input. These parts can be operated from a supply of 2.5V to 5.5V.
DAC B 4-Quadrant Resistors. Allow a number of configuration modes, including bipolar operation with a
minimum of external components.
External Amplifier Output.
DAC A Analog Ground. This pin typically should be tied to the analog ground of the system, but can be biased
to achieve single-supply operation.
DAC B Current Output.
DAC A Current Output.
DAC A Analog Ground. This pin typically should be tied to the analog ground of the system, but can be biased
to achieve single-supply operation.
DB7
DB6
DB5
DB4
DB3
DB2
DB1
20
14
16
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