FEATURES
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LTC2411/LTC2411-1
24-Bit No Latency
∆Σ™
ADC
with Differential Input and
Reference in MSOP
DESCRIPTION
The
LTC
®
2411/LTC2411-1
are 2.7V to 5.5V micropower
24-bit differential ∆Σ analog-to-digital converters with
an integrated oscillator, 2ppm INL and 0.29ppm RMS
noise. They use delta-sigma technology and provide single
cycle settling time for multiplexed applications. Through
a single pin, the LTC2411 can be configured for better
than 110dB differential mode rejection at 50Hz or 60Hz
±2%, and the LTC2411-1 can provide better than 87dB
input differential mode rejection over the range of 49Hz
to 61.2Hz, or they can be driven by an external oscillator
for a user-defined rejection frequency. The LTC2411 and
LTC2411-1 are identical when driven by an external oscil-
lator. The internal oscillator requires no external frequency
setting components.
The converters accept any external differential reference
voltage from 0.1V to V
CC
for flexible ratiometric and re-
mote sensing measurement configurations. The full-scale
differential input range is from –0.5V
REF
to 0.5V
REF
. The
reference common mode voltage, V
REFCM
, and the input
common mode voltage, V
INCM
, may be independently set
anywhere within the GND to V
CC
range of the LTC2411/
LTC2411-1. The DC common mode input rejection is
better than 140dB.
The LTC2411/LTC2411-1 communicate through a flexible
3-wire digital interface that is compatible with SPI and
MICROWIRE protocols.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No
Latency ∆Σ is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
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24-Bit ADC in an MS10 Package
Low Supply Current (200µA in Conversion Mode
and 4µA in Autosleep Mode)
Differential Input and Differential Reference with
GND to V
CC
Common Mode Range
2ppm INL, No Missing Codes
4ppm Full-Scale Error and 1ppm Offset
0.29ppm Noise
No Latency: Digital Filter Settles in a Single Cycle.
Each Conversion Is Accurate, Even After an
Input Step
Single Supply 2.7V to 5.5V Operation
Internal Oscillator—No External Components
Required
110dB Min, Pin Selectable 50Hz/60Hz Notch Filter
(LTC2411)
Simultaneous 50Hz/60Hz Rejection (LTC2411-1)
APPLICATIONS
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Direct Sensor Digitizer
Weight Scales
Direct Temperature Measurement
Gas Analyzers
Strain Gauge Transducers
Instrumentation
Data Acquisition
Industrial Process Control
6-Digit DVMs
TYPICAL APPLICATION
2.7V TO 5.5V
1µF
1
V
CC
F
O
10
V
CC
V
CC
1µF
REFERENCE
VOLTAGE
0.1V TO V
CC
ANALOG INPUT RANGE
–0.5V
REF
TO 0.5V
REF
2
3
4
5
6
LTC2411/
LTC2411-1
REF
+
REF
–
IN
+
= INTERNAL OSC/50Hz REJECTION (LTC2411)
= EXTERNAL CLOCK SOURCE
= INTERNAL OSC/60Hz REJECTION (LTC2411)
= SIMULTANEOUS 50Hz/60Hz REJECTION (LTC2411-1)
BRIDGE
IMPEDANCE
100 TO 10k
4
5
2
1
REF
+
V
CC
LTC2411/
LTC2411-1
F
O
10
2411 TA02
9 SCK
8 SDO
7
CS
3-WIRE
SPI
INTERFACE
SCK
9
3-WIRE
SPI INTERFACE
IN
+
IN
–
3
SDO
CS
8
7
2411 TA01
REF
–
GND
6
IN
–
GND
2411fa
For more information
www.linear.com/LTC2411
1
LTC2411/LTC2411-1
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2)
PIN CONFIGURATION
TOP VIEW
V
CC
REF
+
REF
–
IN
+
IN
–
1
2
3
4
5
10
9
8
7
6
F
O
SCK
SDO
CS
GND
Supply Voltage (V
CC
) to GND ....................... –0.3V to 7V
Analog Input Pins Voltage
to GND ......................................–0.3V to (V
CC
+ 0.3V)
Reference Input Pins Voltage
to GND ......................................–0.3V to (V
CC
+ 0.3V)
Digital Input Voltage to GND .........–0.3V to (V
CC
+ 0.3V)
Digital Output Voltage to GND.......–0.3V to (V
CC
+ 0.3V)
Operating Temperature Range
LTC2411C ................................................ 0°C to 70°C
LTC2411I .............................................–40°C to 85°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................... 300°C
MS10 PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 125°C,
θ
JA
= 120°C/W
ORDER INFORMATION
LEAD FREE FINISH
LTC2411CMS#PBF
LTC2411IMS#PBF
LTC2411-1CMS#PBF
LTC2411-1IMS#PBF
TAPE AND REEL
LTC2411CMS#TRPBF
LTC2411IMS#TRPBF
LTC2411-1CMS#TRPBF
LTC2411-1IMS#TRPBF
PART MARKING
LTNS
LTNT
LTWV
LTNN
PACKAGE DESCRIPTION
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
TEMPERATURE RANGE
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.
Consult LTC Marketing for information on nonstandard 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/
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Notes 3, 4)
PARAMETER
Integral Nonlinearity
CONDITIONS
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ELECTRICAL CHARACTERISTICS
MIN
24
TYP
1
2
6
5
20
MAX
UNITS
Bits
ppm of V
REF
ppm of V
REF
ppm of V
REF
µV
nV/°C
Resolution (No Missing Codes) 0.1V ≤ V
REF
≤ V
CC
, –0.5 • V
REF
≤ V
IN
≤ 0.5 • V
REF
(Note 5)
4.5V ≤ V
CC
≤ 5.5V, REF
+
= 2.5V, REF
–
= GND, V
INCM
= 1.25V (Note 6)
5V ≤ V
CC
≤ 5.5V, REF
+
= 5V, REF
–
= GND, V
INCM
= 2.5V (Note 6)
REF
+
= 2.5V, REF
–
= GND, V
INCM
= 1.25V (Note 6)
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
GND ≤ IN
+
= IN
–
≤ V
CC
(Note 14)
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
GND ≤ IN
+
= IN
–
≤ V
CC
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
IN
+
= 0.75REF
+
, IN
–
= 0.25 • REF
+
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
IN
+
= 0.75REF
+
, IN
–
= 0.25 • REF
+
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
IN
+
= 0.25 • REF
+
, IN
–
= 0.75 • REF
+
14
20
Offset Error
Offset Error Drift
Positive Full-Scale Error
Positive Full-Scale Error Drift
Negative Full-Scale Error
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0.04
12
ppm of V
REF
ppm of V
REF
/°C
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4
12
ppm of V
REF
2411fa
2
For more information
www.linear.com/LTC2411
LTC2411/LTC2411-1
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Notes 3, 4)
PARAMETER
Negative Full-Scale Error Drift
Total Unadjusted Error
CONDITIONS
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
IN
+
= 0.25 • REF
+
, IN
–
= 0.75 • REF
+
4.5V ≤ V
CC
≤ 5.5V, REF
+
= 2.5V, REF
–
= GND, V
INCM
= 1.25V
5V ≤ V
CC
≤ 5.5V, REF
+
= 5V, REF
–
= GND, V
INCM
= 2.5V
REF
+
= 2.5V, REF
–
= GND, V
INCM
= 1.25V
5V ≤ V
CC
≤ 5.5V, REF
+
= 5V, V
REF–
= GND,
GND ≤ IN
–
= IN
+
≤ 5V, (Note 13)
MIN
TYP
0.04
3
3
6
1.45
MAX
UNITS
ppm of V
REF
/°C
ppm of V
REF
ppm of V
REF
ppm of V
REF
µV
RMS
ELECTRICAL CHARACTERISTICS
Output Noise
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Notes 3, 4)
PARAMETER
Input Common Mode Rejection DC
Input Common Mode Rejection
60Hz ±2% (LTC2411)
Input Common Mode Rejection
50Hz ±2% (LTC2411)
Input Common Mode Rejection
49Hz to 61.2Hz (LTC2411-1)
Input Normal Mode Rejection
60Hz ±2% (LTC2411)
Input Normal Mode Rejection
50Hz ±2% (LTC2411)
Input Normal Mode Rejection
49Hz to 61.2Hz (LTC2411-1)
Reference Common Mode
Rejection DC
Power Supply Rejection, DC
Power Supply Rejection, 60Hz ±2%
(LTC2411)
Power Supply Rejection, 50Hz ±2%
(LTC2411)
Power Supply Rejection,
49Hz to 61.2Hz (LTC2411-1)
CONDITIONS
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
GND ≤ IN
–
= IN
+
≤ 5V
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
GND ≤ IN
–
= IN
+
≤ 5V, (Note 7)
2.5V ≤ REF
+
≤ V
CC
, REF
–
= GND,
GND ≤ IN
–
= IN
+
≤ 5V, (Note 8)
2.5V < REF
+
< V
CC
, REF
–
= GND,
GND < IN
–
= IN
+
< V
CC
(Note 15)
(Note 7)
(Note 8)
(Note 15)
2.5V ≤ REF
+
≤ V
CC
, GND ≤ REF
–
≤ 2.5V,
V
REF
= 2.5V, IN
–
= IN
+
= GND
REF
+
= 2.5V, REF
–
= GND, IN
–
= IN
+
= GND
REF
+
= 2.5V, REF
–
= GND, IN
–
= IN
+
= GND, (Note 7)
REF
+
= 2.5V, REF
–
= GND, IN
–
= IN
+
= GND, (Note 8)
REF
+
= 2.5V, REF
–
= GND, IN
–
= IN
+
= GND, (Note 15)
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CONVERTER CHARACTERISTICS
MIN
130
140
140
140
110
110
87
130
TYP
140
MAX
UNITS
dB
dB
dB
dB
140
140
dB
dB
dB
140
110
120
120
120
dB
dB
dB
dB
dB
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 3)
SYMBOL
IN
+
IN
–
V
IN
REF
+
REF
–
V
REF
PARAMETER
Absolute/Common Mode IN
+
Voltage
Absolute/Common Mode IN
–
Voltage
Input Differential Voltage Range
(IN
+
– IN
–
)
Absolute/Common Mode REF
+
Voltage
Absolute/Common Mode REF
–
Voltage
Reference Differential Voltage Range
(REF
+
– REF
–
)
CONDITIONS
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ANALOG INPUT AND REFERENCE
MIN
GND – 0.3V
GND – 0.3V
–V
REF
/2
0.1
GND
0.1
TYP
MAX
V
CC
+ 0.3V
V
CC
+ 0.3V
V
REF
/2
V
CC
V
CC
– 0.1V
V
CC
UNITS
V
V
V
V
V
V
2411fa
For more information
www.linear.com/LTC2411
3
LTC2411/LTC2411-1
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 3)
SYMBOL
C
S
(IN
+
)
C
S
(IN
–
)
C
S
(REF
+
)
C
S
(REF
–
)
I
DC_LEAK
(IN
+
)
I
DC_LEAK
(IN
–
)
I
DC_LEAK
(REF
+
)
I
DC_LEAK
(REF
–
)
PARAMETER
IN
+
Sampling Capacitance
IN
–
Sampling Capacitance
REF
+
Sampling Capacitance
REF
–
Sampling Capacitance
IN
+
DC Leakage Current
IN
–
DC Leakage Current
REF
+
DC Leakage Current
REF
–
DC Leakage Current
CS
= V
CC
= 5.5V, IN
+
= GND
CS
= V
CC
= 5.5V, IN
–
= GND
CS
= V
CC
= 5.5V, REF
+
= 5V
CS
= V
CC
= 5.5V, REF
–
= GND
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ANALOG INPUT AND REFERENCE
CONDITIONS
MIN
TYP
6
6
6
6
MAX
UNITS
pF
pF
pF
pF
–10
–10
–10
–10
1
1
1
1
10
10
10
10
nA
nA
nA
nA
The
l
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. (Note 3)
SYMBOL
V
IH
V
IL
V
IH
V
IL
I
IN
I
IN
C
IN
C
IN
V
OH
V
OL
V
OH
V
OL
I
OZ
PARAMETER
High Level Input Voltage
CS,
F
O
Low Level Input Voltage
CS,
F
O
High Level Input Voltage
SCK
Low Level Input Voltage
SCK
Digital Input Current
CS,
F
O
Digital Input Current
SCK
Digital Input Capacitance
CS,
F
O
Digital Input Capacitance
SCK
High Level Output Voltage
SDO
Low Level Output Voltage
SDO
High Level Output Voltage
SCK
Low Level Output Voltage
SCK
Hi-Z Output Leakage
SDO
(Note 9)
I
O
= –800µA
I
O
= 1.6mA
I
O
= –800µA (Note 10)
I
O
= 1.6mA (Note 10)
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DIGITAL INPUTS AND DIGITAL OUTPUTS
CONDITIONS
2.7V ≤ V
CC
≤ 5.5V
2.7V ≤ V
CC
≤ 3.3V
4.5V ≤ V
CC
≤ 5.5V
2.7V ≤ V
CC
≤ 5.5V
2.7V ≤ V
CC
≤ 5.5V (Note 9)
2.7V ≤ V
CC
≤ 3.3V (Note 9)
4.5V ≤ V
CC
≤ 5.5V (Note 9)
2.7V ≤ V
CC
≤ 5.5V (Note 9)
0V ≤ V
IN
≤ V
CC
0V ≤ V
IN
≤ V
CC
(Note 9)
MIN
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TYP
MAX
UNITS
V
V
2.5
2.0
0.8
0.6
2.5
2.0
0.8
0.6
–10
–10
10
10
V
CC
– 0.5V
0.4
V
CC
– 0.5V
0.4
–10
10
10
10
V
V
V
V
V
V
µA
µA
pF
pF
V
V
V
V
V
V
V
V
µA
The
l
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 3)
SYMBOL
V
CC
I
CC
PARAMETER
Supply Voltage
Supply Current
Conversion Mode
Sleep Mode
Sleep Mode
CS
= 0V (Note 12)
CS
= V
CC
(Note 12)
CS
= V
CC
, 2.7V ≤ V
CC
≤ 3.3V (Note 12)
CONDITIONS
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POWER REQUIREMENTS
MIN
2.7
TYP
MAX
5.5
UNITS
V
µA
µA
µA
2411fa
200
4
2
300
10
4
For more information
www.linear.com/LTC2411
LTC2411/LTC2411-1
The
l
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 3)
SYMBOL
f
EOSC
t
HEO
t
LEO
t
CONV
PARAMETER
External Oscillator Frequency Range
External Oscillator High Period
External Oscillator Low Period
Conversion Time
F
O
= 0V (LTC2411)
F
O
= V
CC
(LTC2411)
F
O
= 0V (LTC2411-1)
External Oscillator (Note 11)
Internal Oscillator (LTC2411) (Note 10)
Internal Oscillator (LTC2411-1) (Note 10)
External Oscillator (Notes 10, 11)
(Note 10)
(Note 9)
(Note 9)
(Note 9)
Internal Oscillator (LTC2411) (Notes 10, 12)
Internal Oscillator (LTC2411-1) (Notes 10, 12)
External Oscillator (Notes 10, 11)
(Note 9)
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TIMING CHARACTERISTICS
CONDITIONS
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MIN
2.56
0.25
0.25
TYP
MAX
500
390
390
UNITS
kHz
µs
µs
ms
ms
ms
ms
kHz
kHz
kHz
130.86
133.53
136.20
157.03
160.23
163.44
143.78
146.71
149.64
20510/f
EOSC
(in kHz)
19.2
17.5
f
EOSC
/8
45
250
250
1.64
1.80
1.67
1.70
1.83
1.86
256/f
EOSC
(in kHz)
32/f
ESCK
(in kHz)
0
0
0
50
220
15
50
50
200
200
200
55
2000
f
ISCK
Internal SCK Frequency
D
ISCK
f
ESCK
t
LESCK
t
HESCK
Internal SCK Duty Cycle
External SCK Frequency Range
External SCK Low Period
External SCK High Period
%
kHz
ns
ns
ms
ms
ms
ms
ns
ns
ns
ns
ns
ns
ns
ns
t
DOUT_ISCK
Internal SCK 32-Bit Data Output Time
t
DOUT_ESCK
External SCK 32-Bit Data Output Time
t
1
t
2
t
3
t
4
t
KQMAX
t
KQMIN
t
5
t
6
CS
↓
to SDO Low Z
CS
↑
to SDO High Z
CS
↓
to SCK
↓
CS
↓
to SCK
↑
SCK
↓
to SDO Valid
SDO Hold After SCK
↓
SCK Set-Up Before
CS
↓
SCK Hold After
CS
↓
(Note 10)
(Note 9)
(Note 5)
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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:
All voltage values are with respect to GND.
Note 3:
V
CC
= 2.7 to 5.5V unless otherwise specified.
V
REF
= REF
+
– REF
–
, V
REFCM
= (REF
+
+ REF
–
)/2;
V
IN
= IN
+
– IN
–
, V
INCM
= (IN
+
+ IN
–
)/2.
Note 4:
F
O
pin tied to GND or to V
CC
or to external conversion clock source
with f
EOSC
= 153600Hz unless otherwise specified.
Note 5:
Guaranteed by design, not subject to test.
Note 6:
Integral nonlinearity is defined as the deviation of a code from a
straight line passing through the actual endpoints of the transfer curve.
The deviation is measured from the center of the quantization band.
Note 7:
F
O
= 0V (internal oscillator) or f
EOSC
= 153600Hz ±2% (external
oscillator).
Note 8:
F
O
= V
CC
(internal oscillator) or f
EOSC
= 128000Hz ±2% (external
oscillator).
Note 9:
The converter is in external SCK mode of operation such that the
SCK pin is used as digital input. The frequency of the clock signal driving
SCK during the data output is f
ESCK
and is expressed in kHz.
Note 10:
The converter is in internal SCK mode of operation such that the
SCK pin is used as digital output. In this mode of operation the SCK pin
has a total equivalent load capacitance C
LOAD
= 20pF.
Note 11:
The external oscillator is connected to the F
O
pin. The external
oscillator frequency, f
EOSC
, is expressed in kHz.
Note 12:
The converter uses the internal oscillator.
F
O
= 0V or F
O
= V
CC
.
Note 13:
The output noise includes the contribution of the internal
calibration operations.
Note 14:
Guaranteed by design and test correlation.
Note 15:
F
O
= 0V (internal oscillator) or f
EOSC
= 139800Hz ±2% (external
oscillator).
2411fa
For more information
www.linear.com/LTC2411
5
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