FEATURES
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LTC1665/LTC1660
Micropower Octal
8-Bit and 10-Bit DACs
DESCRIPTION
The 8-bit LTC
®
1665 and 10-bit LTC1660 integrate eight
accurate, serially addressable digital-to-analog convert-
ers (DACs) in tiny 16-pin narrow SSOP packages. Each
buffered DAC draws just 56μA total supply current, yet
is capable of supplying DC output currents in excess
of 5mA and reliably driving capacitive loads to 1000pF.
Sleep mode further reduces total supply current to 1μA.
Linear Technology’s proprietary, inherently monotonic volt-
age interpolation architecture provides excellent linearity
while allowing for an exceptionally small external form factor.
Ultralow supply current, power-saving Sleep mode and
extremely compact size make the LTC1665 and LTC1660
ideal for battery-powered applications, while their ease
of use, high performance and wide supply range make
them excellent choices as general purpose converters.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Tiny: 8 DACs in the Board Space of an SO-8
Micropower: 56μA per DAC Plus
1μA Sleep Mode for Extended Battery Life
Pin Compatible 8-Bit LTC1665 and 10-Bit LTC1660
Wide 2.7V to 5.5V Supply Range
Rail-to-Rail Voltage Outputs Drive 1000pF
Reference Range Includes Supply for Ratiometric
0V-to-V
CC
Output
Reference Input Impedance is Constant—
Eliminates External Buffer
APPLICATIONS
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Mobile Communications
Remote Industrial Devices
Automatic Calibration for Manufacturing
Portable Battery-Powered Instruments
Trim/Adjust Applications
BLOCK DIAGRAM
GND
1
16 V
CC
DAC A
DAC H
LTC1665 Differential Nonlinearity (DNL)
0.5
0.4
0.3
0.2
V
CC
= 5V
V
REF
= 4.096V
V
OUT A
2
15 V
OUT H
LSB
0.1
0
–0.1
–0.2
V
OUT B
3
DAC B
DAC G
14 V
OUT G
–0.3
–0.4
–0.5
0
64
128
CODE
192
255
166560 G09
V
OUT C
4
DAC C
DAC F
13 V
OUT F
LTC1660 Differential Nonlinearity (DNL)
1
V
OUT D
5
DAC D
DAC E
12 V
OUT E
0.8
0.6
0.4
REF
6
CONTROL
LOGIC
ADDRESS
DECODER
11
CLR
LSB
0.2
0
–0.2
–0.4
SCK
8
SHIFT REGISTER
9
D
IN
166560 BD
V
CC
= 5V
V
REF
= 4.096V
CS/LD
7
10
D
OUT
–0.6
–0.8
–1
0
256
512
CODE
768
1023
166560 G13
166560fa
1
LTC1665/LTC1660
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
TOP VIEW
GND
V
OUT A
V
OUT B
V
OUT C
V
OUT D
REF
CS/LD
SCK
1
2
3
4
5
6
7
8
16 V
CC
15 V
OUT H
14 V
OUT G
13 V
OUT F
12 V
OUT E
11
CLR
10 D
OUT
9
D
IN
V
CC
to GND ............................................... –0.2V to 7.5V
Logic Inputs to GND ................................. –0.2V to 7.5V
V
OUT A
, V
OUT B
, V
OUT H
,
REF to GND .................................–0.2V to (V
CC
+ 0.2V)
Maximum Junction Temperature .......................... 125°C
Operating Temperature Range
LTC1665C/LTC1660C .............................. 0°C to 70°C
LTC1665I/LTC1660I ............................ –40°C to 85°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
GN PACKAGE
N PACKAGE
16-LEAD PLASTIC SSOP
16-LEAD PDIP
T
JMAX
= 125°C,
θ
JA
= 150°C/W (GN)
T
JMAX
= 125°C,
θ
JA
= 100°C/W (N)
ORDER INFORMATION
LEAD FREE FINISH
LTC1665CGN#PBF
LTC1665IGN#PBF
LTC1660CGN#PBF
LTC1660IGN#PBF
LTC1665CN#PBF
LTC1665IN#PBF
LTC1660CN#PBF
LTC1660IN#PBF
TAPE AND REEL
LTC1665CGN#PBF
LTC1665IGN#PBF
LTC1660CGN#PBF
LTC1660IGN#PBF
LTC1665CN#PBF
LTC1665IN#PBF
LTC1660CN#PBF
LTC1660IN#PBF
PART MARKING*
1665
1665I
1660
1660I
LTC1665CN
LTC1665IN
LTC1660CN
LTC1660IN
PACKAGE DESCRIPTION
16-Lead Plastic SSOP
16-Lead Plastic SSOP
16-Lead Plastic SSOP
16-Lead Plastic SSOP
16-Lead Plastic PDIP
16-Lead Plastic PDIP
16-Lead Plastic PDIP
16-Lead Plastic PDIP
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.
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/
166560fa
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LTC1665/LTC1660
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
Accuracy
Resolution
Monotonicity
DNL
INL
V
OS
FSE
PSR
Differential Nonlinearity
Integral Nonlinearity
Offset Error
V
OS
Temperature Coefficient
Full-Scale Error
Full-Scale Error Temperature Coefficient
Power Supply Rejection
V
REF
= 2.5V
V
CC
= 5V, V
REF
= 4.096V
V
REF
≤ V
CC
– 0.1V (Note 2)
V
REF
≤ V
CC
– 0.1V (Note 2)
V
REF
≤ V
CC
– 0.1V (Note 2)
(Note 7)
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l
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l
l
The
l
denotes 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
REF
≤ V
CC
, V
OUT
unloaded, unless otherwise noted.
LTC1665
CONDITIONS
MIN
8
8
± 0.1
±0.2
±10
±15
±1
±30
0.045
±4
±0.5
±1.0
±30
TYP
MAX
MIN
10
10
±0.2
±0.6
±10
±15
±3
±30
0.18
±15
±0.75
±2.5
±30
LTC1660
TYP
MAX
UNITS
Bits
Bits
LSB
LSB
mV
μV/°C
LSB
μV/°C
LSB/V
The
l
denotes 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
REF
≤ V
CC
, V
OUT
unloaded, unless otherwise noted.
SYMBOL PARAMETER
Reference Input
Input Voltage Range
Resistance
Capacitance
I
REF
V
CC
I
CC
Reference Current
Positive Supply Voltage
Supply Current
Power Supply
For Specified Performance
V
CC
= 5V (Note 3)
V
CC
= 3V (Note 3)
Sleep Mode (Note 3)
V
OUT
= 0V, V
CC
= 5.5V, V
REF
= 5.1V, Code = Full
Scale
V
OUT
= V
CC
= 5.5V, V
REF
= 5.1V, Code = 0
Rising (Notes 4, 5)
Falling (Notes 4, 5)
To ±0.5LSB (Notes 4, 5)
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CONDITIONS
MIN
0
35
TYP
MAX
V
CC
UNITS
V
kΩ
pF
Not in Sleep Mode
(Note 6)
Sleep Mode
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65
15
0.001
1
5.5
450
340
1
730
530
3
100
120
μA
V
μA
μA
μA
mA
mA
V/μs
V/μs
μs
pF
V
V
2.7
DC Performance
Short-Circuit Current Low
Short-Circuit Current High
AC Performance
Voltage Output Slew Rate
Voltage Output Settling Time
Capacitive Load Driving
Digital I/O
V
IH
V
IL
V
OH
V
OL
I
LK
C
IN
Digital Input High Voltage
Digital Input Low Voltage
Digital Output High Voltage
Digital Output Low Voltage
Digital Input Leakage
Digital Input Capacitance
V
CC
= 2.7V to 5.5V
V
CC
= 2.7V to 3.6V
V
CC
= 4.5V to 5.5V
V
CC
= 2.7V to 5.5V
I
OUT
= –1mA, D
OUT
Only
I
OUT
= 1mA, D
OUT
Only
V
IN
= GND to V
CC
(Note 6)
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10
10
30
27
0.60
0.25
30
1000
2.4
2.0
0.8
0.6
V
CC
– 1
0.4
±10
10
V
V
V
V
μA
pF
166560fa
3
LTC1665/LTC1660
The
l
denotes specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (See Figure 1)
SYMBOL PARAMETER
V
CC
= 4.5V to 5.5V
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
t
11
D
IN
Valid to SCK Setup
D
IN
Valid to SCK Hold
SCK High Time
SCK Low Time
CS/LD
Pulse Width
LSB SCK High to
CS/LD
High
CS/LD
Low to SCK High
D
OUT
Propagation Delay
SCK Low to
CS/LD
Low
CLR
Pulse Width
CS/LD
High to SCK Positive Edge
SCK Frequency
(Note 6)
(Note 6)
(Note 6)
(Note 6)
(Note 6)
C
LOAD
= 15pF (Note 6)
(Note 6)
(Note 6)
(Note 6)
Continuous Square Wave (Note 6)
Continuous 23% Duty Cycle Pulse (Note 6)
Gated Square Wave (Note 6)
(Note 6)
(Note 6)
(Note 6)
(Note 6)
(Note 6)
(Note 6)
(Note 6)
C
LOAD
= 15pF (Note 6)
(Note 6)
(Note 6)
(Note 6)
Continuous Square Wave (Note 6)
Continuous 28% Duty Cycle Pulse
Gated Square Wave
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l
l
l
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TIMING CHARACTERISTICS
CONDITIONS
MIN
40
0
30
30
80
30
80
5
20
100
30
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
80
ns
ns
ns
ns
5.00
7.69
16.7
60
0
50
50
100
50
100
5
30
120
30
3.85
5.55
10
150
MHz
MHz
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
MHz
MHz
MHz
V
CC
= 2.7V to 5.5V
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
t
11
D
IN
Valid to SCK Setup
D
IN
Valid to SCK Hold
SCK High Time
SCK Low Time
CS/LD
Pulse Width
LSB SCK High to
CS/LD
High
CS/LD
Low to SCK High
D
OUT
Propagation Delay
SCK Low to
CS/LD
Low
CLR
Pulse Width
CS/LD
High to SCK Positive Edge
SCK Frequency
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:
Nonlinearity and monotonicity are defined from code 4 to code
255 for the LTC1665 and from code 20 to code 1023 for the LTC1660.
See Applications Information.
Note 3:
Digital inputs at 0V or V
CC
.
Note 4:
Load is 10kΩ in parallel with 100pF.
Note 5:
V
CC
= V
REF
= 5V. DAC switched between 0.1V
FS
and 0.9V
FS
,
i.e., codes 26 and 230 for the LTC1665 or codes 102 and 922 for the
LTC1660.
Note 6:
Guaranteed by design and not production tested.
Note 7:
Measured at code 4 for the LTC1665 and code 20 for the
LTC1660.
166560fa
4
LTC1665/LTC1660
TYPICAL PERFORMANCE CHARACTERISTICS
Midscale Output Voltage
vs Load Current
3
2.9
2.8
2.7
V
OUT
(V)
2.6
2.5
2.4
2.3
2.2
2.1
2
–30
–20
SOURCE
–10
SINK
20
30
V
CC
= 4.5V
V
CC
= 5V
V
CC
= 5.5V
V
OUT
(V)
V
REF
= V
CC
CODE = 128 (LTC1665)
CODE = 512 (LTC1660)
2
1.9
1.8
1.6
1.5
1.4
1.3
1.2
1.1
1
–15 –12
–8
SOURCE
SINK
0
–4
0
4
I
OUT
(mA)
8
12 15
166560 G02
(LTC1665/LTC1660)
Minimum Supply Headroom
vs
Load Current (Output Sourcing)
1400
1200
1000
V
CC
– V
OUT
(mV)
800
600
–55°C
400
200
V
REF
= 4.096V
ΔV
OUT
< 1LSB
CODE = 255 (LTC1665)
CODE = 1023 (LTC1660)
125°C
25°C
Midscale Output Voltage
vs Load Current
V
REF
= V
CC
CODE = 128 (LTC1665)
CODE = 512 (LTC1660)
V
CC
= 3.6V
V
CC
= 3V
1.7
V
CC
= 2.7V
0
10
I
OUT
(mA)
0
2
|
I
OUT
|
(mA) (SOURCING)
4
6
8
10
166560 G03
166560 G01
Minimum V
OUT
vs Load Current (Output Sinking)
1400
1200
1000
V
OUT
(mV)
V
OUT
(V)
800
25°C
600
–55°C
400
1
200
0
0
2
0
3
V
CC
= 5V
CODE = 0
5
125°C
Large-Signal Step Response
V
CC
= V
REF
= 5V
10% TO
90% STEP
4
2
|
4
6
8
I
OUT
(mA) (SINKING)
|
10
166560 G04
0
20
40
60
TIME (μs)
80
100
166560 G05
Supply Current vs Temperature
500
480
460
SUPPLY CURRENT (μA)
440
420
400
380
360
340
320
300
–55 –35 –15
0
5 25 45 65 85 105 125
TEMPERATURE (°C)
166560 G06
Supply Current
vs Logic Input Voltage
2
ALL DIGITAL INPUTS
SHORTED TOGETHER
V
CC
= 5.5V
V
CC
= 4.5V
V
CC
= 3.6V
SUPPLY CURRENT (mA)
1.6
1.2
0.8
V
CC
= 2.7V
0.4
0
1
2
3
4
LOGIC INPUT VOLTAGE (V)
5
166560 G07
166560fa
5