No Latency ∆∑™ ADC with Easy Drive technology and a
2-wire, I
2
C interface. The patented sampling scheme elimi-
nates dynamic input current errors and the shortcomings
of on-chip buffering through automatic cancellation of
differential input current. This allows large external source
impedances and rail-to-rail input signals to be directly digi-
tized while maintaining exceptional DC accuracy.
The LTC2493 includes a high accuracy temperature
sensor and an integrated oscillator. This device can be
configured to measure an external signal (from combi-
nations of 4 analog input channels operating in single-
ended or differential modes) or its internal temperature
sensor. The integrated temperature sensor offers 1/30th °C
resolution and 2°C absolute accuracy.
The LTC2493 allows a wide common mode input range
(0V to V
CC
), independent of the reference voltage. Any
combination of single-ended or differential inputs can
be selected and the first conversion, after a new channel
is selected, is valid. Access to the multiplexer output en-
ables optional external amplifiers to be shared between all
analog inputs and auto-calibration continuously removes
their associated offset and drift.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
No Latency ∆∑ and Easy Drive are trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
n
n
n
n
n
n
n
n
n
n
n
n
n
Up to 2 Differential or 4 Single-Ended Inputs
Easy Drive™ Technology Enables Rail-to-Rail
Inputs with Zero Differential Input Current
Directly Digitizes High Impedance Sensors with
Full Accuracy
2-Wire I
2
C Interface with 9 Addresses Plus One
Global Address for Synchronization
600nV RMS Noise
Integrated High Accuracy Temperature Sensor
GND to V
CC
Input/Reference Common Mode Range
Programmable 50Hz, 60Hz or Simultaneous
50Hz/60Hz Rejection Mode
2ppm INL, No Missing Codes
1ppm Offset and 15ppm Full-Scale Error
2× Speed/Reduced Power Mode (15Hz Using Internal
Oscillator and 80µA at 7.5Hz Output)
No Latency: Digital Filter Settles in a Single Cycle,
Even After a New Channel Is Selected
Single Supply 2.7V to 5.5V Operation (0.8mW)
Internal Oscillator
Tiny 4mm × 3mm DFN Package
applicaTions
n
n
n
n
Direct Sensor Digitizer
Direct Temperature Measurement
Instrumentation
Industrial Process Control
Typical applicaTion
Data Acquisition System with Temperature Compensation
2.7V TO 5.5V
CH0
CH1
IN
+
REF
+
SDA
SCL
CA1
CA0
f
O
OSC
2493 vTA01a
Integrated High Performance Temperature Sensor
5
10µF
ABSOLUTE ERROR (°C)
4
3
2
1
0
–1
–2
–3
–4
–5
–55
–30
–5
20
45
70
TEMPERATURE (°C)
95
120
2493 TA02
V
CC
0.1µF
1.7k
2-WIRE
I
2
C INTERFACE
9-PIN SELECTABLE
ADDRESSES
CH2
CH3
COM
4-CHANNEL
MUX
24-BIT ∆∑ ADC
WITH EASY-DRIVE
IN
–
REF
–
TEMPERATURE
SENSOR
2493fe
For more information
www.linear.com/LTC2493
1
LTC2493
absoluTe MaxiMuM raTings
(Notes 1, 2)
pin conFiguraTion
f
O
CA0
CA1
SCL
SDA
GND
COM
1
2
3
4
5
6
7
15
14 REF
–
13 REF
+
12 V
CC
11 CH3
10 CH2
9 CH1
8 CH0
Supply Voltage (V
CC
) ................................... –0.3V to 6V
Analog Input Voltage
(CH0 to CH3, COM).................. –0.3V to (V
CC
+ 0.3V)
REF
+
, REF
–
.................................. –0.3V to (V
CC
+ 0.3V)
Digital Input Voltage..................... –0.3V to (V
CC
+ 0.3V)
Digital Output Voltage .................. –0.3V to (V
CC
+ 0.3V)
Operating Temperature Range
LTC2493C ................................................ 0°C to 70°C
LTC2493I .............................................–40°C to 85°C
Storage Temperature Range ..................–65°C to 150°C
DE PACKAGE
14-LEAD (4mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 37°C/W
EXPOSED PAD (PIN 15) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH
LTC2493CDE#PBF
LTC2493IDE#PBF
TAPE AND REEL
LTC2493CDE#TRPBF
LTC2493IDE#TRPBF
PART MARKING*
2493
2493
PACKAGE DESCRIPTION
14-Lead (4mm × 3mm) Plastic DFN
14-Lead (4mm × 3mm) Plastic DFN
TEMPERATURE RANGE
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.
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/
2
2493fe
For more information
www.linear.com/LTC2493
LTC2493
elecTrical characTerisTics (norMal speeD)
PARAMETER
Resolution (No Missing Codes)
Integral Nonlinearity
Offset Error
Offset Error Drift
Positive Full-Scale Error
Positive Full-Scale Error Drift
Negative Full-Scale Error
Negative Full-Scale Error Drift
Total Unadjusted Error
CONDITIONS
0.1V ≤ V
REF
≤ V
CC
, –FS ≤ V
IN
≤ +FS (Note 5)
5V ≤ V
CC
≤ 5.5V, V
REF
= 5V, V
IN(CM)
= 2.5V (Note 6)
2.7V ≤ V
CC
≤ 5.5V, V
REF
= 2.5V, V
IN(CM)
= 1.25V (Note 6)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Note 13)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.75V
REF
, IN
–
= 0.25V
REF
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.75V
REF
, IN
–
= 0.25V
REF
–
2.5V ≤ V
REF
≤ V
CC
REF
, IN = 0.75V
REF
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.25V
REF
, IN
–
= 0.75V
REF
The
l
denotes the specifications which
apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C. (Notes 3, 4)
MIN
24
l
l
l
TYP
2
1
0.5
10
MAX
10
2.5
25
UNITS
Bits
ppm of V
REF
ppm of V
REF
µV
nV/°C
ppm of V
REF
ppm of V
REF
/°C
ppm of V
REF
ppm of V
REF
/°C
ppm of V
REF
ppm of V
REF
ppm of V
REF
µV
RMS
l
0.1
l
, IN
+
= 0.25V
25
0.1
15
15
15
0.6
27.8
28.0
93.5
28.2
5V ≤ V
CC
≤ 5.5V, V
REF
= 2.5V, V
IN(CM)
= 1.25V
5V ≤ V
CC
≤ 5.5V, V
REF
= 5V, V
IN(CM)
= 2.5V
2.7V ≤ V
CC
≤ 5.5V, V
REF
= 2.5V, V
IN(CM)
= 1.25V
2.7V < V
CC
< 5.5V, 2.5V ≤ V
REF
≤ V
CC
,
GND ≤ IN
+
= IN
–
≤ V
CC
(Note 12)
T
A
= 27°C (Note 13)
Output Noise
Internal PTAT Signal
Internal PTAT Temperature Coefficient
mV
µV/°C
elecTrical characTerisTics (2x speeD)
PARAMETER
Resolution (No Missing Codes)
Integral Nonlinearity
Offset Error
Offset Error Drift
Positive Full-Scale Error
Positive Full-Scale Error Drift
Negative Full-Scale Error
Negative Full-Scale Error Drift
Output Noise
CONDITIONS
0.1V ≤ V
REF
≤ V
CC
, –FS ≤ V
IN
≤ +FS (Note 5)
The
l
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. (Notes 3, 4)
MIN
24
l
l
TYP
2
1
0.2
100
MAX
10
2
25
UNITS
Bits
ppm of V
REF
ppm of V
REF
mV
nV/°C
ppm of V
REF
ppm of V
REF
/°C
ppm of V
REF
ppm of V
REF
/°C
µV
RMS
5V ≤ V
CC
≤ 5.5V, V
REF
= 5V, V
IN(CM)
= 2.5V (Note 6)
2.7V ≤ V
CC
≤ 5.5V, V
REF
= 2.5V, V
IN(CM)
= 1.25V (Note 6)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Note 13)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.75V
REF
, IN
–
= 0.25V
REF
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.75V
REF
, IN
–
= 0.25V
REF
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.25V
REF
, IN
–
= 0.75V
REF
2.5V ≤ V
REF
≤ V
CC
, IN
+
= 0.25V
REF
, IN
–
= 0.75V
REF
5V ≤ V
CC
≤ 5.5V, V
REF
= 5V, GND ≤ IN
+
= IN
–
≤ V
CC
l
0.1
l
25
0.1
0.85
converTer characTerisTics
PARAMETER
Input Common Mode Rejection DC
Input Common Mode Rejection 50Hz ±2%
Input Common Mode Rejection 60Hz ±2%
Input Normal Mode Rejection 50Hz ±2%
Input Normal Mode Rejection 60Hz ±2%
Input Normal Mode Rejection 50Hz/60Hz ±2%
Reference Common Mode Rejection DC
Power Supply Rejection DC
Power Supply Rejection, 50Hz ±2%, 60Hz ±2%
CONDITIONS
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 3)
MIN
l
l
l
l
l
l
l
TYP
MAX
UNITS
dB
dB
dB
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Note 5)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Notes 5, 7)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Notes 5, 8)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Notes 5, 7)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Notes 5, 8)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Notes 5, 9)
2.5V ≤ V
REF
≤ V
CC
, GND ≤ IN
+
= IN
–
≤ V
CC
(Note 5)
V
REF
= 2.5V, IN
+
= IN
–
= GND
V
REF
= 2.5V, IN
+
= IN
–
= GND (Notes 7, 8, 9)
140
140
140
110
110
87
120
140
120
120
120
120
dB
dB
dB
dB
dB
dB
2493fe
For more information
www.linear.com/LTC2493
3
LTC2493
analog inpuT anD reFerence
SYMBOL
IN
+
IN
–
PARAMETER
Absolute/Common Mode IN
+
Voltage
(IN
+
Corresponds to the Selected Positive Input Channel)
Absolute/Common Mode IN
–
Voltage
(IN
–
Corresponds to the Selected Negative Input Channel
to COM)
Input Voltage Range (IN
+
– IN
–
)
Full-Scale of the Input (IN
+
– IN
–
)
Least Significant Bit of the Output Code
Absolute/Common Mode REF
+
Voltage
Absolute/Common Mode REF
–
Voltage
Reference Voltage Range (REF
+
– REF
–
)
IN
+
Sampling Capacitance
IN
–
Sampling Capacitance
V
REF
Sampling Capacitance
IN
+
DC Leakage Current
IN
–
DC Leakage Current
Sleep Mode, IN
+
= GND
Sleep Mode, IN
–
= GND
Sleep Mode, REF
+
= V
CC
Sleep Mode, REF
–
= GND
V
IN
= 2V
P-P
DC to 1.8MHz
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. (Note 3)
CONDITIONS
MIN
GND – 0.3V
GND – 0.3V
TYP
MAX
V
CC
+ 0.3V
V
CC
+ 0.3V
+FS
UNITS
V
V
V
IN
FS
LSB
REF
+
REF
–
V
REF
CS(IN
+
)
CS(IN
–
)
CS(V
REF
)
I
DC_LEAK(IN+)
I
DC_LEAK(IN–)
Differential/Single-Ended
Differential/Single-Ended
l
l
l
l
l
l
–FS
0.5V
REF
FS/2
24
0.1
GND
0.1
11
11
11
–10
–10
–100
–100
1
1
1
1
50
120
V
V
V
CC
REF
+
– 0.1V
V
CC
V
V
V
pF
pF
pF
10
10
100
100
nA
nA
nA
nA
ns
dB
I
DC_LEAK(REF+)
REF
+
DC Leakage Current
I
DC_LEAK(REF–)
REF
–
DC Leakage Current
t
OPEN
QIRR
MUX Break-Before-Make
MUX Off Isolation
i
2
c inpuTs anD DigiTal ouTpuTs
SYMBOL
V
IH
V
IL
V
IHA
V
ILA
R
INH
R
INL
R
INF
I
I
V
HYS
V
OL
t
OF
I
IN
C
CAX
PARAMETER
High Level Input Voltage
Low Level Input Voltage
Low Level Input Voltage for Address Pins CA0, CA1 and
Pin f
O
High Level Input Voltage for Address Pins CA0, CA1
Resistance from CA0, CA1 to V
CC
to Set Chip Address
Bit to 1
Resistance from CA0, CA1 to GND to Set Chip Address
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