FEATURES
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LTC2632
Dual 12-/10-/8-Bit SPI
V
OUT
DACs with
10ppm/°C Reference
DESCRIPTION
The LTC
®
2632 is a family of dual 12-, 10-, and 8-bit voltage-
output DACs with an integrated, high-accuracy, low-drift
reference in an 8-lead TSOT-23 package. It has rail-to-rail
output buffers and is guaranteed monotonic.
The LTC2632-L has a full-scale output of 2.5V, and operates
from a single 2.7V to 5.5V supply. The LTC2632-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 simple SPI/MICROWIRE
compatible 3-wire serial interface which operates at clock
rates up to 50MHz. The LTC2632 incorporates a power-on
reset circuit. Options are available for reset to zero-scale
or reset to mid-scale in internal reference mode, or reset
to mid-scale in external reference mode after power-up.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other
trademarks are the property of their respective owners. Protected by U.S. Patents including
5396245, 5859606, 6891433, and 6937178.
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Integrated Precision Reference
2.5V Full-Scale 10ppm/°C (LTC2632-L)
4.096V Full-Scale 10ppm/°C (LTC2632-H)
Maximum INL Error: ±1LSB (LTC2632A-12)
Low Noise: 0.75mV
P-P
0.1Hz to 200kHz
Guaranteed Monotonic –40°C to 125°C Automotive
Temperature Range
Selectable Internal or External Reference
2.7V to 5.5V Supply Range (LTC2632-L)
Low Power Operation 0.4mA at 3V
Power-On-Reset to Zero-Scale/Mid-Scale
Double-Buffered Data Latches
8-Lead ThinSOT™ Package
APPLICATIONS
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Mobile Communications
Process Control and Industrial Automation
Automatic Test Equipment
Portable Equipment
Automotive
BLOCK DIAGRAM
Integral Nonlinearity (LTC2632A-LZ12)
GND
INTERNAL
REFERENCE
SWITCH
V
REF
REF
2
V
CC
= 3V
INTERNAL REF
.
V
CC
REGISTER
REGISTER
REGISTER
REGISTER
1
INL (LSB)
V
OUTA
DAC A
DAC B
V
OUTB
0
–1
CS/LD
CONTROL
LOGIC
SDI
DECODE
–2
0
1024
2048
CODE
3072
4095
2632 TA01
SCK
32-BIT SHIFT REGISTER
POWER-ON
RESET
2632 BD
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LTC2632
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2)
PIN CONFIGURATION
TOP VIEW
SCK
CS/LD
REF
GND
1
2
3
4
8
7
6
5
SDI
V
CC
V
OUTB
V
OUTA
Supply Voltage (V
CC
) ................................... –0.3V to 6V
SCK, SDI ...................................................... –0.3V to 6V
CS/LD
(Note 11) ...............–0.3V to Min (V
CC
+ 0.3V, 6V)
V
OUTA
, V
OUTB
...................–0.3V to Min (V
CC
+ 0.3V, 6V)
REF ..................................–0.3V to Min (V
CC
+ 0.3V, 6V)
Operating Temperature Range
LTC2632C ................................................ 0°C to 70°C
LTC2632H (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)................... 300°C
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
T
JMAX
= 150°C (NOTE 6),
θ
JA
= 195°C/W
ORDER INFORMATION
LTC2632 A
C
TS8 –L
Z
12
#TRM PBF
LEAD FREE DESIGNATOR
TAPE AND REEL
TR = 2,500-Piece Tape and Reel
TRM = 500-Piece Tape and Reel
RESOLUTION
12 = 12-Bit
10 = 10-Bit
8 = 8-Bit
POWER-ON RESET
I = Reset to Mid-Scale in Internal Reference Mode
X = Reset to Mid-Scale in External Reference Mode (2632-L Only)
Z = Reset to Zero-Scale in Internal Reference Mode
FULL-SCALE VOLTAGE, INTERNAL REFERENCE MODE
L = 2.5V
H = 4.096V
PACKAGE TYPE
TS8 = 8-Lead Plastic TSOT-23
TEMPERATURE GRADE
C = Commercial Temperature Range (0°C to 70°C)
H = Automotive Temperature Range (–40°C to 125°C)
ELECTRICAL GRADE (OPTIONAL)
A = ±1LSB Maximum INL (12-Bit)
PRODUCT PART NUMBER
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/
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LTC2632
PRODUCT SELECTION GUIDE
PART NUMBER
LTC2632A-LI12
LTC2632A-LX12
LTC2632A-LZ12
LTC2632A-HI12
LTC2632A-HZ12
LTC2632-LI12
LTC2632-LI10
LTC2632-LI8
LTC2632-LX12
LTC2632-LX10
LTC2632-LX8
LTC2632-LZ12
LTC2632-LZ10
LTC2632-LZ8
LTC2632-HI12
LTC2632-HI10
LTC2632-HI8
LTC2632-HZ12
LTC2632-HZ10
LTC2632-HZ8
PART MARKING*
LTFSJ
LTFSH
LTFSG
LTFSM
LTFSK
LTFSJ
LTFSQ
LTFSW
LTFSH
LTFSP
LTFSV
LTFSG
LTFSN
LTFST
LTFSM
LTFSS
LTFSY
LTFSK
LTFSR
LTFSX
V
FS
WITH INTERNAL
REFERENCE
2.5V • (4095/4096)
2.5V • (4095/4096)
2.5V • (4095/4096)
4.096V • (4095/4096)
4.096V • (4095/4096)
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
POWER-ON
RESET TO CODE REFERENCE MODE
Mid-Scale
Mid-Scale
Zero
Mid-Scale
Zero
Mid-Scale
Mid-Scale
Mid-Scale
Mid-Scale
Mid-Scale
Mid-Scale
Zero
Zero
Zero
Mid-Scale
Mid-Scale
Mid-Scale
Zero
Zero
Zero
Internal
External
Internal
Internal
Internal
Internal
Internal
Internal
External
External
External
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
Internal
RESOLUTION
12-Bit
12-Bit
12-Bit
12-Bit
12-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
4.5V to 5.5V
4.5V 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
±1LSB
±1LSB
±1LSB
±1LSB
±1LSB
±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
* The temperature grade is identified by a label on the shipping container.
Above options are available in an 8-lead TSOT package (LTC2632xTS8).
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LTC2632
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
DC Performance
Resolution
Monotonicity
DNL
INL
ZSE
V
OS
V
OSTC
GE
GE
TC
Differential
Nonlinearity
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.
(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
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l
l
l
l
l
l
l
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.
LTC2632-8
LTC2632-10
LTC2632-12
LTC2632A-12
MIN TYP MAX MIN TYP MAX MIN TYP MAX MIN TYP MAX
8
8
±0.5
±0.05
0.5
±0.5
±10
±0.5
5
±5
±0.2
0.5
±0.5
±10
10
10
±0.5
±1
5
±5
±1
0.5
±0.5
±10
12
12
±1
±2.5
5
±5
±0.5
0.5
±0.5
±10
12
12
±1
±1
5
±5
LTC2632-LI12/-LI10/-LI8/-LX12/-LX10/-LX8/-LZ12/-LZ10/-LZ8, LTC2632A-LI12/-LX12/-LZ12 (V
FS
= 2.5V)
CONDITIONS
UNITS
Bits
Bits
LSB
LSB
mV
mV
µV/°C
l
0.2
0.8
0.2
0.8
0.2
0.8
0.2
0.8
%FSR
10
10
0.009 0.016
0.009 0.016
10
10
0.035 0.064
0.035 0.064
10
10
0.14 0.256
0.14 0.256
10
10
ppm/°C
ppm/°C
0.14 0.256 LSB/mA
0.14 0.256 LSB/mA
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 0.156
0.09 0.156
0.09 0.156
0.09 0.156
Ω
Ω
SYMBOL
V
OUT
PSR
I
SC
PARAMETER
DAC Output Span
Power Supply Rejection
Short-Circuit Output Current (Note 6)
Sinking
Sourcing
Positive Supply Voltage
Supply Current (Note 7)
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
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
l
l
MIN
TYP
0 to V
REF
0 to 2.5
–80
27
–28
MAX
UNITS
V
V
dB
48
–48
5.5
mA
mA
V
mA
mA
mA
mA
µA
Power Supply
V
CC
I
CC
l
l
l
l
l
l
2.7
0.3
0.4
0.3
0.4
0.5
0.5
0.6
0.5
0.6
2
I
SD
Supply Current in Power-Down Mode
(Note 7)
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LTC2632
ELECTRICAL CHARACTERISTICS
SYMBOL
PARAMETER
Input Voltage Range
Resistance
Capacitance
I
REF
Reference Current, Power-Down Mode
Output Voltage
Reference Temperature Coefficient
Output Impedance
Capacitive Load Driving
Short-Circuit Current
Digital I/O
V
IH
V
IL
I
LK
C
IN
t
S
Digital Input High Voltage
Digital Input Low Voltage
Digital Input Leakage
Digital Input Capacitance
Settling Time
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
V
IN
= GND to V
CC
(Note 8)
V
CC
= 3V (Note 9)
±0.39% (±1LSB at 8 Bits)
±0.098% (±1LSB at 10 Bits)
±0.024% (±1LSB at 12 Bits)
l
l
l
l
l
l
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.
LTC2632-LI12/-LI10/-LI8/-LX12/-LX10/-LX8/-LZ12/-LZ10/-LZ8, LTC2632A-LI12/-LX12/-LZ12 (V
FS
= 2.5V)
CONDITIONS
l
l
MIN
1
120
TYP
MAX
V
CC
UNITS
V
kΩ
pF
µA
V
ppm/°C
kΩ
µF
mA
V
V
Reference Input
160
12
DAC Powered Down
l
200
5.0
1.26
0.005
1.24
1.25
±10
0.5
10
Reference Output
l
V
CC
= 5.5V, REF Shorted to GND
2.4
2.0
2.5
0.8
0.6
±1
8
V
V
µA
pF
AC Performance
3.5
3.9
4.4
1.0
500
At Mid-Scale Transition
1 DAC Held at FS, 1 DAC Switch 0 to FS
External Reference
At f = 1kHz, External Reference
At f = 10kHz, External Reference
At f = 1kHz, Internal Reference
At f = 10kHz, Internal Reference
0.1Hz to 10Hz, External Reference
0.1Hz to 10Hz, Internal Reference
0.1Hz to 200kHz, External Reference
0.1Hz to 200kHz, Internal Reference
C
REF
= 0.1µF
2.8
4.5
320
180
160
200
180
30
35
680
730
µs
µs
µs
V/µs
pF
nV•s
nV•s
kHz
nV/√Hz
nV/√Hz
nV/√Hz
nV/√Hz
µV
P-P
µV
P-P
µV
P-P
µV
P-P
Voltage Output Slew Rate
Capacitive Load Driving
Glitch Impulse
DAC-to-DAC Crosstalk
Multiplying Bandwidth
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Output Voltage Noise Density
Output Voltage Noise
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