LTC2635
Quad 12-/10-/8-Bit I
2
C V
OUT
DACs with 10ppm/°C Reference
FEATURES
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DESCRIPTION
The
LTC
®
2635
is a family of quad 12-, 10-, and 8-bit
voltage-output DACs with an integrated, high-accuracy,
low-drift reference in a 16-pin QFN or a 10-lead MSOP
package. It has rail-to-rail output buffers and is guaran-
teed monotonic. The LTC2635-L has a full-scale output
of 2.5V, and operates from a single 2.7V to 5.5V supply.
The LTC2635-H has a full-scale output of 4.096V, and
operates from a 4.5V to 5.5V supply. Each DAC can also
operate with an external reference, which sets the full-
scale output to the external reference voltage.
These DACs communicate via a 2-wire I
2
C-compatible
serial interface. The LTC2635 operates in both the stan-
dard mode (clock rate of 100kHz) and the fast mode (clock
rate of 400kHz). The LTC2635 incorporates a power-on
reset circuit. Options are available for reset to zero-scale,
reset to mid-scale in internal reference mode, reset to
mid-scale in external reference mode, or reset with all
DAC outputs in a high-impedance state after power-up.
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. patents, including 5396245, 5859606, 6891433, 6937178, 7414561.
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Integrated Precision Reference
2.5V Full-Scale 10ppm/°C (LTC2635-L)
4.096V Full-Scale 10ppm/°C (LTC2635-H)
Maximum INL Error: ±2.5 LSB (LTC2635-12)
Power-On-Reset to Zero-Scale/Mid-Scale/Hi-Z
Low Noise: 0.75mV
P-P
0.1Hz to 200kHz
Guaranteed Monotonic Over –40°C to 125°C
Automotive Temperature Range
Selectable Internal or External Reference
2.7V to 5.5V Supply Range (LTC2635-L)
Ultralow Crosstalk Between DACs (3nV•s)
Low Power: 0.6mA at 3V
Double-Buffered Data Latches
Small 16-Pin 3mm × 3mm QFN and 10-Lead MSOP
Packages
APPLICATIONS
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Mobile Communications
Process Control and Industrial Automation
Power Supply Margining
Portable Equipment
Automotive
BLOCK DIAGRAM
GND
INTERNAL
REFERENCE
SWITCH
V
REF
(REFLO)
REGISTER
REGISTER
REGISTER
V
OUTA
REGISTER
V
CC
V
OUTD
REF
Integral Nonlinerity
2
V
CC
= 3V
INTERNAL REF
.
1
INL (LSB)
DAC A
DAC D
V
REF
REGISTER
REGISTER
REGISTER
V
OUTB
REGISTER
DAC B
DAC C
V
REF
V
OUTC
0
–1
(LDAC)
DECODE
CA0
(CA1)
(CA2)
I
2
C
ADDRESS
DECODE
POWER-ON
RESET
SCL
–2
0
1024
2048
CODE
3072
4095
2635 TA01
I
2
C INTERFACE
SDA
( ) QFN PACKAGE ONLY
2635 BD
Rev D
Document Feedback
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1
LTC2635
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2)
Supply Voltage (V
CC
) ................................... –0.3V to 6V
SCL, SDA, REFLO,
LDAC
.............................. –0.3V to 6V
V
OUTA-D
, CA0, CA1, CA2 ..... –0.3V to Min (V
CC
+ 0.3V, 6V)
REF ................................... –0.3V to Min (V
CC
+ 0.3V, 6V)
Operating Temperature Range
LTC2635C ................................................ 0°C to 70°C
LTC2635H (Note 3) ............................ –40°C to 125°C
Maximum Junction Temperature ......................... 150°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
MS Package ...................................................... 300°C
PIN CONFIGURATION
TOP VIEW
REFLO
GND
DNC
V
CC
16 15 14 13
V
OUTA
1
V
OUTB
2
LDAC
3
CA0 4
5
SCL
6
DNC
7
CA2
8
SDA
17
GND
12 V
OUTD
11 V
OUTC
10 REF
9
CA1
V
CC
V
OUTA
V
OUTB
CA0
SCL
1
2
3
4
5
TOP VIEW
11
GND
10
9
8
7
6
GND
V
OUTD
V
OUTC
REF
SDA
UD PACKAGE
16-LEAD (3mm × 3mm) PLASTIC QFN
T
JMAX
= 150°C,
θ
JA
= 68°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
MSE PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 35°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
Rev D
2
For more information
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LTC2635
ORDER INFORMATION
LTC2635
C
UD
–L
Z
12
http://www.linear.com/product/LTC2635#orderinfo
#TR
PBF
LEAD FREE DESIGNATOR
PBF = Lead Free
TAPE AND REEL
TR = 2,500-Piece Tape and Reel
RESOLUTION
12 = 12-Bit
10 = 10-Bit
8 = 8-Bit
POWER-0N RESET
MI = Reset to Mid-Scale in Internal Reference Mode
MX = Reset to Mid-Scale in External Reference Mode (LMX Only)
MO = Reset to Mid-Scale in Internal Reference Mode, DAC Outputs Hi-Z (LMO Only)
Z = Reset to Zero-Scale in Internal Reference Mode
FULL-SCALE VOLTAGE, INTERNAL REFERENCE MODE
L = 2.5V
H = 4.096V
PACKAGE TYPE
UD = 16-Pin QFN
MSE = 10-Lead MSOP
TEMPERATURE GRADE
C = Commercial Temperature Range (0°C to 70°C)
H = Automotive Temperature Range (–40°C to 125°C)
PRODUCT PART NUMBER
Consult LTC Marketing for parts specified with wider operating temperature ranges.
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/.
Some packages are available in 500 unit reels through
designated sales channels with #TRMPBF suffix.
Rev D
For more information
www.analog.com
3
LTC2635
PRODUCT SELECTION GUIDE
PART MARKING*
PART NUMBER
LTC2635-LMI12
LTC2635-LMI10
LTC2635-LMI8
LTC2635-LMX12
LTC2635-LMX10
LTC2635-LMX8
LTC2635-LZ12
LTC2635-LZ10
LTC2635-LZ8
LTC2635-LMO12**
LTC2635-LMO10**
LTC2635-LMO8**
LTC2635-HMI12
LTC2635-HMI10
LTC2635-HMI8
LTC2635-HZ12
LTC2635-HZ10
LTC2635-HZ8
QFN
LDZB
LDZJ
LDZR
LDYZ
LDZH
LDZQ
LDYY
LDZG
LDZP
LFBT
LFBV
LFBW
LDZF
LDZN
LDZV
LDZC
LDZK
LDZS
MSOP
LTDZY
LTFBG
LTFBP
LTDZX
LTFBF
LTFBN
LTDZW
LTFBD
LTFBM
LTFBX
LTFBY
LTFBZ
LTFBC
LTFBK
LTFBS
LTDZZ
LTFBH
LTFBQ
VFS WITH INTERNAL
REFERENCE
2.5V • (4095/4096)
2.5V • (1023/1024)
2.5V • (255/256)
2.5V • (4095/4096)
2.5V • (1023/1024)
2.5V • (255/256)
2.5V • (4095/4096)
2.5V • (1023/1024)
2.5V • (255/256)
2.5V • (4095/4096)
2.5V • (1023/1024)
2.5V • (255/256)
4.096V • (4095/4096)
4.096V • (1023/1024)
4.096V • (255/256)
4.096V • (4095/4096)
4.096V • (1023/1024)
4.096V • (255/256)
POWER-ON
RESET TO CODE
Mid-Scale
Mid-Scale
Mid-Scale
Mid-Scale
Mid-Scale
Mid-Scale
Zero-Scale
Zero-Scale
Zero-Scale
High Impedance
High Impedance
High Impedance
Mid-Scale
Mid-Scale
Mid-Scale
Zero-Scale
Zero-Scale
Zero-Scale
POWER-ON
REFERENCE
MODE
Internal
Internal
Internal
External
External
External
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
RESOLUTION
12-Bit
10-Bit
8-Bit
12-Bit
10-Bit
8-Bit
12-Bit
10-Bit
8-Bit
12-Bit
10-Bit
8-Bit
12-Bit
10-Bit
8-Bit
12-Bit
10-Bit
8-Bit
V
CC
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
4.5V to 5.5V
MAXIMUM
INL
±2.5LSB
±1LSB
±0.5LSB
±2.5LSB
±1LSB
±0.5LSB
±2.5LSB
±1LSB
±0.5LSB
±2.5LSB
±1LSB
±0.5LSB
±2.5LSB
±1LSB
±0.5LSB
±2.5LSB
±1LSB
±0.5LSB
*Above options are available in a 16-pin QFN package (LTC2635xUD) or 10-lead MSOP package (LTC2635xMSE).
**Contact Linear Technology for other Hi-Z options.
Rev D
4
For more information
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LTC2635
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 2.7V to 5.5V, V
OUT
unloaded unless otherwise specified.
LTC2635-LMI12/-LMI10/-LMI8/-LMX12/-LMX10/-LMX8/-LZ12/-LZ10/-LZ8/-LMO12/-LMO10/-LM08 (V
FS
= 2.5V)
LTC2635-8
SYMBOL PARAMETER
DC Performance
Resolution
Monotonicity
DNL
INL
ZSE
V
OS
V
OSTC
GE
GE
TC
Integral Nonlinearity
Zero-Scale Error
Offset Error
V
OS
Temperature
Coefficient
Gain Error
Gain Temperature
Coefficient
Load Regulation
V
CC
= 3V, Internal Ref. (Note 4)
V
CC
= 3V, Internal Ref. (Note 4)
V
CC
= 3V, Internal Ref., Code=0
V
CC
= 3V, Internal Ref. (Note 5)
V
CC
= 3V, Internal Ref.
V
CC
= 3V, Internal Ref.
V
CC
= 3V, Internal Ref. (Note 10)
C-Grade
H-Grade
Internal Ref., Mid-Scale,
V
CC
= 3V ± 10%,
–5mA ≤ I
OUT
≤ 5mA
V
CC
= 5V±10%,
–10mA ≤ I
OUT
≤ 10mA
Internal Ref., Mid-Scale,
V
CC
= 3V ± 10%,
–5mA ≤ I
OUT
≤ 5mA
V
CC
= 5V±10%,
–10mA ≤ I
OUT
≤ 10mA
l
l
l
l
l
l
l
l
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
LTC2635-10
MIN
10
10
TYP
MAX
LTC2635-12
MIN
12
12
TYP
MAX
UNITS
Bits
Bits
±1
±1
0.5
±0.5
±10
±2.5
5
±5
LSB
LSB
mV
mV
µV/°C
±0.8
%FSR
ppm/°C
ppm/°C
0.256
0.256
LSB/
mA
LSB/
mA
Ω
Ω
MIN
8
8
TYP
MAX
Differential Nonlinearity V
CC
= 3V, Internal Ref. (Note 4)
±0.5
±0.05
0.5
±0.5
±10
±0.2
10
10
0.009 0.016
0.009 0.016
±0.8
±0.5
5
±5
±0.2
0.5
±0.5
±10
±0.2
10
10
±0.5
±1
5
±5
±0.8
±0.2
10
10
0.14
0.14
0.035 0.064
0.035 0.064
R
OUT
DC Output Impedance
l
l
0.09
0.09
0.156
0.156
0.09
0.09
0.156
0.156
0.09
0.09
0.156
0.156
SYMBOL
V
OUT
PSR
I
SC
DAC I
SD
Power Supply
V
CC
I
CC
PARAMETER
DAC Output Span
Power Supply Rejection
Short Circuit Output Current (Note 6)
Sinking
Sourcing
CONDITIONS
External Reference
Internal Reference
V
CC
= 3V ± 10% or 5V ± 10%
V
FS
= V
CC
= 5.5V
Zero-Scale; V
OUT
Shorted to V
CC
Full-Scale; V
OUT
Shorted to GND
l
l
l
l
MIN
TYP
0 to V
REF
0 to 2.5
–80
27
–28
0.05
–0.001
MAX
UNITS
V
V
dB
48
–48
2
–0.1
5.5
mA
mA
µA
µA
V
mA
mA
mA
mA
µA
µA
DAC Output Current in High Impedance Mode MO Options Only
Sinking
Sourcing
Positive Supply Voltage
Supply Current (Note 7)
For Specified Performance
V
CC
= 3V, V
REF
= 2.5V, External Reference
V
CC
= 3V, Internal Reference
V
CC
= 5V V
REF
= 2.5V, External Reference
V
CC
= 5V, Internal Reference
V
CC
= 5V, C-Grade
V
CC
= 5V, H-Grade
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l
l
l
l
l
l
2.7
0.5
0.6
0.6
0.7
1
1
0.7
0.8
0.8
0.9
20
30
I
SD
Supply Current in Power-Down Mode
(Note 7)
Rev D
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5
