unbuffered voltage output DACs. These DACs operate from
a single 2.7V to 5.5V supply and are guaranteed monotonic
over temperature. The LTC2641-16/LTC2642-16 provide
16-bit performance (±2LSB INL and ±1LSB DNL) over
temperature. Unbuffered DAC outputs result in low supply
current of 120μA and a low offset error of ±1LSB.
Both the LTC2641 and LTC2642 feature a reference input
range of 2V to V
DD
. V
OUT
swings from 0V to V
REF
. For
bipolar operation, the LTC2642 includes matched scaling
resistors for use with an external precision op amp (such
as the LT1678), generating a ±V
REF
output swing at R
FB
.
The LTC2641/LTC2642 use a simple SPI/MICROWIRE
compatible 3-wire serial interface which can be operated
at clock rates up to 50MHz and can interface directly
with optocouplers for applications requiring isolation. A
power-on reset circuit clears the LTC2641’s DAC output
to zero scale and the LTC2642’s DAC output to midscale
when power is initially applied. A logic low on the
⎯
C
⎯
L
⎯
R pin
asynchronously clears the DAC to zero scale (LTC2641)
or midscale (LTC2642). These DACs are all specified over
the commercial and industrial ranges.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Tiny 3mm
×
3mm 8-Pin DFN Package
Maximum 16-Bit INL Error: ±2LSB over Temperature
Low 120μA Supply Current
Guaranteed Monotonic over Temperature
Low 0.5nV•sec Glitch Impulse
2.7V to 5.5V Single Supply Operation
Fast 1μs Settling Time to 16 Bits
Unbuffered Voltage Output Directly Drives 60k Loads
50MHz SPI
TM
/QSPI
TM
/MICROWIRE
TM
Compatible
Serial Interface
Power-On Reset Clears DAC Output to Zero Scale
(LTC2641) or Midscale (LTC2642)
Schmitt-Trigger Inputs for Direct Optocoupler
Interface
Asynchronous
⎯
C
⎯
L
⎯
R Pin
8-Lead MSOP and 3mm
×
3mm DFN Packages
(LTC2641)
10-Lead MSOP and 3mm
×
3mm DFN Packages
(LTC2642)
APPLICATIONS
■
■
■
■
High Resolution Offset and Gain Adjustment
Process Control and Industrial Automation
Automatic Test Equipment
Data Aquisition Systems
TYPICAL APPLICATION
Bipolar 16-Bit DAC
2.7V TO 5.5V
0.1μF
LTC2642
V
DD
REF
1μF
0.1μF
R
FB
V
REF
2V TO V
DD
LTC2642-16 Integral Nonlinearity
1.0
0.8
0.6
V
DD
= 5V
V
REF
= 2.5V
±2.5V
RANGE
1/2 LT1678
POWER-ON
RESET
CS
SCLK
DIN
CLR
16-BIT DAC
16-BIT DATA LATCH
CONTROL
LOGIC
16-BIT SHIFT REGISTER
GND
26412 TA01a
+
V
OUT
INL (LSB)
–
BIPOLAR V
OUT
–V
REF
TO V
REF
INV
5pF
0.4
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
0
16384
32768
CODE
49152
65535
LT1372 • G10
INL 25°C
INL 90°C
INL –45°C
26412f
1
LTC2641/LTC2642
ABSOLUTE MAXIMUM RATINGS
(Note 1)
V
DD
to GND .................................................. –0.3V to 6V
⎯
C
⎯
S, SCLK, DIN,
⎯
C
⎯
L
⎯
R to GND ........................ –0.3V to (V
DD
+ 0.3V) or 6V
REF, V
OUT
, INV to GND ........ –0.3V to (V
DD
+ 0.3V) or 6V
R
FB
to INV ....................................................... –6V to 6V
R
FB
to GND ..................................................... –6V to 6V
Operating Temperature Range
LTC2641C/LTC2642C ............................... 0°C to 70°C
LTC2641I/LTC2642I ............................. –40°C to 85°C
Maximum Junction Temperature .......................... 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec) .................. 300°C
PIN CONFIGURATION
LTC2641
TOP VIEW
REF 1
CS 2
SCLK 3
DIN 4
9
8
7
6
5
GND
V
DD
V
OUT
CLR
REF
CS
SCLK
DIN
1
2
3
4
TOP VIEW
8
7
6
5
GND
V
DD
V
OUT
CLR
DD PACKAGE
8-LEAD (3mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C (NOTE 2),
θ
JA
= 43°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
MS8 PACKAGE
8-LEAD PLASTIC MSOP
T
JMAX
= 125°C (NOTE 2),
θ
JA
= 200°C/W
LTC2642
TOP VIEW
REF
CS
SCLK
DIN
CLR
1
2
3
4
5
11
10 GND
9 V
DD
8 R
FB
7 INV
6 V
OUT
REF
CS
SCLK
DIN
CLR
1
2
3
4
5
TOP VIEW
10
9
8
7
6
GND
V
DD
R
FB
INV
V
OUT
DD PACKAGE
10-LEAD (3mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C (NOTE 2),
θ
JA
= 43°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
MS PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 125°C (NOTE 2),
θ
JA
= 120°C/W
26412f
2
LTC2641/LTC2642
ORDER INFORMATION
LTC2641
LEAD FREE FINISH
LTC2641CDD-16#PBF
LTC2641CDD-14#PBF
LTC2641CDD-12#PBF
LTC2641IDD-16#PBF
LTC2641IDD-14#PBF
LTC2641IDD-12#PBF
LTC2641CMS8-16#PBF
LTC2641CMS8-14#PBF
LTC2641CMS8-12#PBF
LTC2641IMS8-16#PBF
LTC2641IMS8-14#PBF
LTC2641IMS8-12#PBF
LTC2642
LTC2642CDD-16#PBF
LTC2642CDD-14#PBF
LTC2642CDD-12#PBF
LTC2642IDD-16#PBF
LTC2642IDD-14#PBF
LTC2642IDD-12#PBF
LTC2642CMS-16#PBF
LTC2642CMS-14#PBF
LTC2642CMS-12#PBF
LTC2642IMS-16#PBF
LTC2642IMS-14#PBF
LTC2642IMS-12#PBF
LTC2642CDD-16#TRPBF
LTC2642CDD-14#TRPBF
LTC2642CDD-12#TRPBF
LTC2642IDD-16#TRPBF
LTC2642IDD-14#TRPBF
LTC2642IDD-12#TRPBF
LTC2642CMS-16#TRPBF
LTC2642CMS-14#TRPBF
LTC2642CMS-12#TRPBF
LTC2642IMS-16#TRPBF
LTC2642IMS-14#TRPBF
LTC2642IMS-12#TRPBF
LCZW
LCZV
LCZT
LCZW
LCZV
LCZT
LTCZZ
LTCZY
LTCZX
LTCZZ
LTCZY
LTCZX
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
0°C to 70°C
0°C to 70°C
0°C to 70°C
–40°C to 85°C
–40°C to 85°C
–40°C to 85°C
0°C to 70°C
0°C to 70°C
0°C to 70°C
–40°C to 85°C
–40°C to 85°C
–40°C to 85°C
TAPE AND REEL
LTC2641CDD-16#TRPBF
LTC2641CDD-14#TRPBF
LTC2641CDD-12#TRPBF
LTC2641IDD-16#TRPBF
LTC2641IDD-14#TRPBF
LTC2641IDD-12#TRPBF
LTC2641CMS8-16#TRPBF
LTC2641CMS8-14#TRPBF
LTC2641CMS8-12#TRPBF
LTC2641IMS8-16#TRPBF
LTC2641IMS8-14#TRPBF
LTC2641IMS8-12#TRPBF
PART MARKING*
LCZP
LCZN
LCZM
LCZP
LCZN
LCZM
LTCZS
LTCZR
LTCZQ
LTCZS
LTCZR
LTCZQ
PACKAGE DESCRIPTION
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
TEMPERATURE RANGE
0°C to 70°C
0°C to 70°C
0°C to 70°C
–40°C to 85°C
–40°C to 85°C
–40°C to 85°C
0°C to 70°C
0°C to 70°C
0°C to 70°C
–40°C to 85°C
–40°C to 85°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/
26412f
3
LTC2641/LTC2642
ELECTRICAL CHARACTERISTICS
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 3V or 5V, V
REF
= 2.5V, C
L
= 10pF, GND = 0, R
L
= ∞ unless
otherwise specified.
LTC2641-12
LTC2642-12
SYMBOL PARAMETER
Static Peformance
N
DNL
INL
ZSE
ZS
TC
GE
GE
TC
R
OUT
Resolution
Monotonicity
Differential Nonlinearity
Integral Nonlinearity
Zero Code Offset Error
Zero Code Tempco
Gain Error
Gain Error Tempco
DAC Output Resistance
Bipolar Resistor Matching
BZE
BZS
TC
PSR
Bipolar Zero Offset Error
Bipolar Zero Tempco
Power Supply Rejection
(Note 4)
(LTC2642) R
FB
/R
INV
Ratio Error (Note 7)
●
(LTC2642)
(LTC2642)
ΔV
DD
= ±10%
●
●
●
●
●
LTC2641-14
LTC2642-14
MAX
MIN
14
14
±0.5
±0.5
1
±0.5
±0.5
±0.05
±2
±1
±0.1
6.2
1
±0.1
±0.03
±0.5
±0.1
±0.5
±0.5
±4
±2
±4
±1
±1
2
TYP
MAX
MIN
16
16
LTC2641-16
LTC2642-16
TYP
MAX
UNITS
Bits
Bits
±0.5
±0.5
±0.05
±2
±0.1
6.2
1
±0.015
±2
±0.1
±1
±5
%
LSB
ppm/°C
LSB
±5
±1
±2
2
LSB
LSB
LSB
ppm/°C
LSB
ppm/°C
kΩ
CONDITIONS
MIN
12
12
TYP
(Note 2)
(Note 2)
Code = 0
●
●
●
±0.05
±0.5
±0.1
6.2
1
±0.5
±0.1
The
●
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
V
DD
= 3V or 5V, V
REF
= 2.5V, C
L
= 10pF, GND = 0, R
L
= ∞ unless otherwise specified.
SYMBOL
Reference Input
V
REF
R
REF
Reference Input Range
Reference Input Resistance (Note 5)
Unipolar Mode (LTC2641)
Bipolar Mode (LTC2642)
Measured from 10% to 90%
To ±0.5LSB of FS
Major Carry Transition
Code = 0000hex; NCS = V
DD
;
SCLK, DIN 0V to V
DD
Levels
Code = FFFFhex
Code = 0000hex, V
REF
= 1V
P-P
at 100kHz
Code = 0000hex
Code = FFFFhex
V
CC
= 3.6V to 5.5V
V
CC
= 2.7V to 3.6V
V
CC
= 4.5V to 5.5V
V
CC
= 2.7V to 4.5V
●
●
●
●
●
●
●
PARAMETER
CONDITIONS
MIN
2.0
11
8.5
TYP
MAX
V
DD
UNITS
V
kΩ
kΩ
V/μs
μs
nV•s
nV•s
14.8
11.4
15
1
0.5
0.2
Dynamic Performance—V
OUT
SR
Voltage Output Slew Rate
Output Settling Time
DAC Glitch Impulse
Digital Feedthrough
Dynamic Performance—Reference Input
BW
SNR
C
IN(REF)
Digital Inputs
V
IH
V
IL
Digital Input High Voltage
Digital Input Low Voltage
2.4
2.0
0.8
0.6
V
V
V
V
26412f
Reference –3dB Bandwidth
Reference Feedthrough
Signal-to-Noise Ratio
Reference Input Capacitance
1.3
1
92
75
120
MHz
mV
P-P
dB
pF
pF
4
LTC2641/LTC2642
ELECTRICAL CHARACTERISTICS
SYMBOL
I
IN
C
IN
V
H
Power Supply
V
DD
I
DD
P
D
Supply Voltage
Supply Current, V
DD
Power Dissipation
Digital Inputs = 0V or V
DD
Digital Inputs = 0V or V
DD
, V
DD
= 5V
Digital Inputs = 0V or V
DD
, V
DD
= 3V
●
●
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 3V or 5V, V
REF
= 2.5V, C
L
= 10pF, GND = 0, R
L
= ∞ unless
otherwise specified.
PARAMETER
Digital Input Current
Digital Input Capacitance
Hysteresis Voltage
2.7
120
0.60
0.36
CONDITIONS
V
IN
= GND to V
CC
(Note 6)
●
●
MIN
TYP
3
0.15
MAX
±1
10
UNITS
μA
pF
V
5.5
200
V
μA
mW
mW
TIMING CHARACTERISTICS
SYMBOL
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
f
SCLK
PARAMETER
DIN Valid to SCLK Setup Time
DIN Valid to SCLK Hold Time
SCLK Pulse Width High
SCLK Pulse Width Low
⎯
C
⎯
S Pulse High Width
LSB SCLK High to
⎯
C
⎯
S High
⎯
C
⎯
S Low to SCLK High
⎯
C
⎯
S High to SCLK Positive Edge
⎯
C
⎯
L
⎯
R Pulse Width Low
The
●
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. V
DD
= 3V or 5V, V
REF
= 2.5V, C
L
= 10pF, GND = 0, R
L
= ∞ unless otherwise specified.
CONDITIONS
●
●
●
●
●
●
●
●
●
●
MIN
10
0
9
9
10
8
8
8
15
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
SCLK Frequency
⎯ ⎯
V
DD
High to CS Low (Power-Up Delay)
50% Duty Cycle
50
30
MHz
μs
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:
LTC2641-16/LTC2642-16 ±1LSB = ±0.0015% = ±15.3ppm of full
scale. LTC2641-14/LTC2642-14 ±1LSB = ±0.006% = ±61ppm of full scale.
LTC2641-12/LTC2642-12 ±1LSB = ±0.024% = ±244ppm of full scale.
Note 4:
R
OUT
tolerance is typically ±20%.
Note 5:
Reference input resistance is code dependent. Minimum is at
871Chex (34,588) in unipolar mode and at 671Chex (26, 396) in bipolar
mode.
Note 6:
Guaranteed by design and not production tested.
Note 7:
Guaranteed by gain error and offset error testing, not production
