plying parallel-input, current-output DACs. They operate
from a single 2.7V to 5.5V supply. All parts are guaranteed
monotonic over temperature. The LTC2751A-16 provides
16-bit performance (±1LSB INL and DNL) over temperature
without any adjustments. These SoftSpan™ DACs offer six
output ranges—two unipolar and four bipolar—that can be
programmed through the parallel interface, or pinstrapped
for operation in a single range.
These parts use a bidirectional input/output parallel in-
terface that allows readback of any on-chip register. A
power-on circuit resets the DAC output to 0V when power is
initially applied. A logic low on the
CLR
pin asynchronously
clears the DAC to 0V in any output range.
The parts are specified over commercial and industrial
temperature ranges.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
n
n
n
n
n
n
n
n
n
n
n
Six Programmable Output Ranges
Unipolar: 0V to 5V, 0V to 10V
Bipolar: ±5V, ±10V, ±2.5V, –2.5V to 7.5V
Maximum 16-Bit INL Error: ±1 LSB over Temperature
Low 1µA (Maximum) Supply Current
Guaranteed Monotonic over Temperature
Low Glitch Impulse 1nV
•
s
2.7V to 5.5V Single Supply Operation
2µs Settling Time to ±1 LSB
Reference Input: ±15V
Parallel Interface with Readback of All Registers
Asynchronous
CLR
Pin Clears DAC Output to 0V in
Any Output Range
Power-On Reset to 0V
38-Pin 5mm
×
7mm QFN Package
applicaTions
n
n
n
n
High Resolution Offset and Gain Adjustment
Process Control and Industrial Automation
Automatic Test Equipment
Data Acquisition Systems
Typical applicaTion
16-Bit DAC with Software Selectable Ranges
REF
5V
LTC2751-16 Integral Nonlinearity
1.0
V
DD
= 5V
0.8 V
REF
= 5V
±10V RANGE
0.6
0.4
INL (LSB)
0.2
0.0
–0.2
–0.4
–0.6
V
OUT
+
1/2 LT
®
1469
–
R
IN
R1
R
COM
C2
150pF
R2
LTC2751-16
REF R
OFS
R
FB
C1
15pF
WR
UPD
READ
D/S
CLR
WR
UPD
READ
D/S
CLR
MSPAN
SPAN I/O
S2-S0
DATA I/O
D15-D0
3
16
R
VOS
16-BIT DAC WITH SPAN SELECT
I
OUT2
GND
V
DD
C3
0.1µF
+
5V
2751 TA01
–
1/2 LT1469
I
OUT1
– 0.8
–1.0
0
16384
32768
CODE
49152
25°C
90°C
–45°C
65535
2751 TA01b
2751fa
1
LTC2751
absoluTe MaxiMuM raTings
(Notes 1, 2)
I
OUT1
, I
OUT2
, R
COM
to GND .....................................±0.3V
R
FB
, R
OFS
, R
IN
, REF, R
VOS
to GND ........................... ±15V
V
DD
to GND .................................................. –0.3V to 7V
S2, S1, S0, D15-D0, MSPAN, READ,
D/S,WR,
UPD,
CLR
to GND........ –0.3V to V
DD
+ 0.3V (7V Max)
Operating Temperature Range
LTC2751C ..................................................... 0°C to 70°C
LTC2751I ..................................................–40°C to 85°C
Maximum Junction Temperature .......................... 125°C
Storage Temperature Range .................. –65°C to 150°C
pin conFiguraTion
I
OUT1
TOP VIEW
I
OUT1
R
VOS
R
OFS
R
OFS
REF
REF
R
FB
S1
S0
TOP VIEW
I
OUT1
R
VOS
R
OFS
REF
R
FB
S1
S0
TOP VIEW
R
VOS
R
FB
S1
S0
31
WR
30 UPD
29 READ
28
D/S
27 NC
39
26 NC
25 D0
24 D1
23 D2
22 D3
21 D4
20 D5
13 14 15 16 17 18 19
MSPAN
GND
CLR
V
DD
D8
D7
D6
38 37 36 35 34 33 32
R
COM
1
R
IN
2
S2 3
I
OUT2
4
NC 5
D11 6
D10 7
D9 8
D8 9
D7 10
D6 11
D5 12
13 14 15 16 17 18 19
GND
CLR
MSPAN
D2
V
DD
D4
D3
39
31
WR
30 UPD
29 READ
28
D/S
27 NC
26 NC
25 NC
24 NC
23 NC
22 NC
21 D0
20 D1
R
COM
1
R
IN
2
S2 3
I
OUT2
4
NC 5
D13 6
D12 7
D11 8
D10 9
D9 10
D8 11
D7 12
13 14 15 16 17 18 19
GND
CLR
MSPAN
V
DD
D6
D5
D4
39
38 37 36 35 34 33 32
31
WR
30 UPD
29 READ
28
D/S
27 NC
26 NC
25 NC
24 NC
23 D0
22 D1
21 D2
20 D3
R
COM
1
R
IN
2
S2 3
I
OUT2
4
NC 5
D15 6
D14 7
D13 8
D12 9
D11 10
D10 11
D9 12
38 37 36 35 34 33 32
LTC2751-12 UHF PACKAGE
38-LEAD (5mm
×
7mm) PLASTIC QFN
LTC2751-14 UHF PACKAGE
38-LEAD (5mm
×
7mm) PLASTIC QFN
LTC2751-16 UHF PACKAGE
38-LEAD (5mm
×
7mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 34°C/W
EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB
T
JMAX
= 125°C,
θ
JA
= 34°C/W
EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB
T
JMAX
= 125°C,
θ
JA
= 34°C/W
EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH
LTC2751CUHF-12#PBF
LTC2751IUHF-12#PBF
LTC2751CUHF-14#PBF
LTC2751IUHF-14#PBF
LTC2751BCUHF-16#PBF
LTC2751BIUHF-16#PBF
LTC2751ACUHF-16#PBF
LTC2751AIUHF-16#PBF
TAPE AND REEL
LTC2751CUHF-12#TRPBF
LTC2751IUHF-12#TRPBF
LTC2751CUHF-14#TRPBF
LTC2751IUHF-14#TRPBF
LTC2751BCUHF-16#TRPBF
LTC2751BIUHF-16#TRPBF
LTC2751ACUHF-16#TRPBF
LTC2751AIUHF-16#TRPBF
PART MARKING*
275112
275112
275114
275114
275116
275116
275116
275116
PACKAGE DESCRIPTION
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
38-Lead (5mm
×
7mm) Plastic QFN
TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
2751fa
2
LTC2751
elecTrical characTerisTics
SYMBOL PARAMETER
Static Performance
Resolution
Monotonicity
DNL
INL
GE
GE
TC
BZE
BZS
TC
PSR
I
LKG
C
IOUT1
Differential
Nonlinearity
Integral
Nonlinearity
Gain Error
Gain Error Temp-
erature Coefficient
Bipolar Zero Error
Bipolar Zero Temp-
erature Coefficient
Power Supply
Rejection
I
OUT1
Leakage
Current
Output
Capacitance
V
DD
= 5V, ±10%
V
DD
= 3V, ±10%
T
A
= 25°C
T
MIN
to T
MAX
Full-Scale
Zero Scale
l
l
l
l
l
l
V
DD
= 5V, V
REF
= 5V unless otherwise specified. The
l
denotes the
specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
LTC2751-12
CONDITIONS
MIN
12
12
±1
±1
±0.5
±0.6
l
LTC2751-14
MIN
14
14
±1
±1
±1.5
±0.6
±5
TYP
MAX
LTC2751B-16
MIN
16
16
±1
±2
±20
±0.6
±3
±0.5
±12
TYP
MAX
LTC2751A-16
MIN
16
16
±0.2
±0.4
±4
±0.6
±2
±0.5
±8
±1
±1
±14
TYP
MAX
UNITS
Bits
Bits
LSB
LSB
LSB
ppm/°C
LSB
ppm/°C
LSB/V
nA
pF
pF
TYP
MAX
All Output
Ranges
DGain/DTemp
All Bipolar
Ranges
l
±2
±0.2
±0.5
±1
±0.6
±0.5
±0.025
±0.06
±0.05
±2
±5
±0.05
75
45
±0.1
±0.25
±2
±5
±0.05
75
45
±0.4
±1
±2
±5
±0.03 ±0.2
±0.1 ±0.5
±0.05
75
45
±2
±5
l
75
45
V
DD
= 5V, V
REF
= 5V unless otherwise specified. The
l
denotes specifications that apply over the full operating temperature range,
otherwise specifications are at T
A
= 25°C.
SYMBOL
Resistances (Note 3)
R1/R2
R
REF
R
FB
R
OFS
R
VOS
Reference Inverting Resistors
DAC Input Resistance
Feedback Resistor
Bipolar Offset Resistor
Offset Adjust Resistor
Output Settling Time
Glitch Impulse
Digital-to-Analog Glitch Impulse
Multiplying Feedthrough Error
THD
Power Supply
V
DD
I
DD
Supply Voltage
Supply Current, V
DD
Digital Inputs = 0V or V
DD
l
l
PARAMETER
CONDITIONS
(Note 4)
(Note 3)
(Note 3)
l
l
l
l
l
MIN
16
8
8
16
800
TYP
20
10
10
20
1000
2
1
1
0.5
–110
13
MAX
UNITS
kW
kW
kW
kW
kW
μs
nV•s
nV•s
mV
dB
nV/√Hz
Dynamic Performance
0V to 10V Range, 10V Step. To ±0.0015% FS
(Note 5)
(Note 6)
(Note 7)
0V to 10V Range, V
REF
= ±10V, 10kHz
Sine Wave
(Note 8) Multiplying
(Note 9) at I
OUT1
2.7
0.5
Total Harmonic Distortion
Output Noise Voltage Density
5.5
1
V
μA
2751fa
3
LTC2751
elecTrical characTerisTics
SYMBOL
Digital Inputs
V
IH
V
IL
I
IN
C
IN
Digital Outputs
V
OH
V
OL
I
OH
= 200µA
I
OL
= 200µA
l
l
V
DD
= 5V, V
REF
= 5V unless otherwise specified. The
l
denotes the
specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
PARAMETER
Digital Input High Voltage
Digital Input Low Voltage
Digital Input Current
Digital Input Capacitance
CONDITIONS
3.3V ≤ V
DD
≤ 5.5V
2.7V ≤ V
DD
< 3.3V
4.5V < V
DD
≤ 5.5V
2.7V ≤ V
DD
≤ 4.5V
V
IN
= GND to V
DD
V
IN
= 0V (Note 10)
l
l
l
l
l
l
MIN
2.4
2
TYP
MAX
UNITS
V
V
0.8
0.6
±1
6
V
DD
– 0.4
0.4
V
V
µA
pF
V
V
TiMing characTerisTics
SYMBOL
PARAMETER
V
DD
= 4.5V to 5.5V
Write and Update Timing
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
13
t
14
t
15
t
17
t
18
t
19
t
20
t
22
t
23
t
24
CLR
Timing
t
25
CLR
Pulse Width Low
I/O Valid to
WR
Rising Edge Set-Up
I/O Valid to
WR
Rising Edge Hold
WR
Pulse Width
UPD Pulse Width
UPD Falling Edge to
WR
Falling Edge
WR
Rising Edge to UPD Rising Edge
D/S
Valid to
WR
Falling Edge Set-Up Time
WR
Rising Edge to
D/S
Valid Hold Time
WR
Rising Edge to READ Rising Edge
READ Falling Edge to
WR
Falling Edge
V
DD
= 5V, V
REF
= 5V unless otherwise specified. The
l
denotes specifications that
apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
CONDITIONS
MIN
TYP
MAX
UNITS
l
l
l
l
9
9
20
20
0
0
9
9
9
20
30
30
9
9
9
9
0
20
20
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
No Data Shoot-Through
(Note 10)
l
l
l
l
Readback Timing
l
(Note 10)
C
L
= 10pF
C
L
= 10pF
(Note 10)
No Update
No Update
(Note 10)
(Note 10)
(Note 10)
l
l
l
l
l
l
l
l
l
READ Rising Edge to I/O Propagation Delay
UPD Valid to I/O Propagation Delay
D/S
Valid to READ Rising Edge
READ Rising Edge to UPD Rising Edge
UPD Falling Edge to READ Falling Edge
READ Falling Edge to UPD Rising Edge
I/O Bus Hi-Z to READ Rising Edge
READ Falling Edge to I/O Bus Active
l
2751fa
4
LTC2751
TiMing characTerisTics
SYMBOL
PARAMETER
V
DD
= 2.7V to 3.3V
Write and Update Timing
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
13
t
14
t
15
t
17
t
18
t
19
t
20
t
22
t
23
t
24
CLR
Timing
t
25
CLR
Pulse Width Low
l
V
DD
= 5V, V
REF
= 5V unless otherwise specified. The
l
denotes specifications that
apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
CONDITIONS
MIN
TYP
MAX
UNITS
I/O Valid to
WR
Rising Edge Set-Up
I/O Valid to
WR
Rising Edge Hold
WR
Pulse Width
UPD Pulse Width
UPD Falling Edge to
WR
Falling Edge
WR
Rising Edge to UPD Rising Edge
D/S
Valid to
WR
Falling Edge Set-Up Time
WR
Rising Edge to
D/S
Valid Hold Time
WR
Rising Edge to Read Rising Edge
Read Falling Edge to
WR
Falling Edge
Read Rising Edge to I/O Propagation Delay
UPD Valid to I/O Propagation Delay
D/S
Valid to Read Rising Edge
Read Rising Edge to UPD Rising Edge
UPD Falling Edge to Read Falling Edge
READ Falling Edge to UPD Rising Edge
I/O Bus Hi-Z to Read Rising Edge
Read Falling Edge to I/O Bus Active
(Note 10)
C
L
= 10pF
C
L
= 10pF
(Note 10)
No Update
No Update
(Note 10)
(Note 10)
(Note 10)
No Data Shoot-Through
(Note 10)
l
l
l
l
l
l
l
l
18
18
30
30
0
0
18
18
18
40
40
40
18
9
9
18
0
40
30
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Readback Timing
l
l
l
l
l
l
l
l
l
l
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
Continuous operation above the specified maximum operating
junction temperature may impair device reliability.
Note 3:
Because of the proprietary SoftSpan switching architecture, the
measured resistance looking into each of the specified pins is constant for
all output ranges if the I
OUT1
and I
OUT2
pins are held at ground.
Note 4:
R1 is measured from R
IN
to R
COM
; R2 is measured from REF to
R
COM
.
Note 5:
Using LT1469 with C
FEEDBACK
= 15pF. A ±0.0015% settling time
of 1.7μs can be achieved by optimizing the time constant on an individual
basis. See Application Note 74, “Component and Measurement Advances
Ensure 16-Bit DAC Settling Time.”
Note 6:
Measured at the major carry transition, 0V to 5V range. Output
amplifier: LT1469; C
FB
= 27pF.
Note 7.
Full-scale transition; REF = 0V.
Note 8.
REF = 6V
RMS
at 1kHz. 0V to 5V range. DAC code = FS. Output
amplifier = LT1469.
Note 9.
Calculation from V
n
= √4kTRB, where k = 1.38E-23 J/°K
(Boltzmann constant), R = resistance (W), T = temperature (°K), and B =
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