LTC2452.pdf 데이터시트 (총 20 페이지) - 파일 다운로드 LTC2452 데이타시트 다운로드

No Preview Available !

FEATURES
n ±VCC Differential Input Range
n 16-Bit Resolution (Including Sign), No Missing
Codes
n 2LSB Offset Error
n 4LSB Full-Scale Error
n 60 Conversions Per Second
n Single Conversion Settling Time for Multiplexed
Applications
n Single-Cycle Operation with Auto Shutdown
n 800μA Supply Current
n 0.2μA Sleep Current
n Internal Oscillator—No External Components
Required
n SPI Interface
n Ultra-Tiny 3mm × 2mm DFN and TSOT-23 Packages
APPLICATIONS
n System Monitoring
n Environmental Monitoring
n Direct Temperature Measurements
n Instrumentation
n Industrial Process Control
n Data Acquisition
n Embedded ADC Upgrades
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 6208279, 6411242, 7088280, 7164378.
www.DataSheet4U.com
LTC2452
Ultra-Tiny, Differential, 16-Bit
ΔΣ ADC with SPI Interface
DESCRIPTION
The LTC®2452 is an ultra-tiny, fully differential, 16-bit,
analog-to-digital converter. The LTC2452 uses a single
2.7V to 5.5V supply and communicates through an SPI
interface. The ADC is available in an 8-pin, 3mm × 2mm
DFN package or TSOT-23 package. It includes an integrated
oscillator that does not require any external components.
It uses a delta-sigma modulator as a converter core and
has no latency for multiplexed applications. The LTC2452
includes a proprietary input sampling scheme that reduces
the average input sampling current several orders of
magnitude when compared to conventional delta-sigma
converters. Additionally, due to its architecture, there is
negligible current leakage between the input pins.
The LTC2452 can sample at 60 conversions per second,
and due to the very large oversampling ratio, has extremely
relaxed antialiasing requirements. The LTC2452 includes
continuous internal offset and full-scale calibration algo-
rithms which are transparent to the user, ensuring accuracy
over time and over the operating temperature range. The
converter has an external REF pin and the differential input
voltage range can extend up to ±VREF.
Following a single conversion, the LTC2452 can automati-
cally enter a sleep mode and reduce its supply current to
less than 0.2μA. If the user reads the ADC once a second,
the LTC2452 consumes an average of less than 50μW
from a 2.7V supply.
TYPICAL APPLICATION
0.1μF
2.7V TO 5.5V
10μF
0.1μF
REF VCC
IN+
CS
10k 10k
IN
LTC2452
SCK 3-WIRE SPI
SDO INTERFACE
10k R 0.1μF
GND
2452 TA01a
Integral Nonlinearity, VCC = 3V
3
2
1
TA = –45°C, 25°C, 90°C
0
–1
–2
–3
–3
–2 –1 0 1 2
DIFFERENTIAL INPUT VOLTAGE (V)
3
2452 TA01b
2452fb
1

No Preview Available !

LTC2452
www.DataSheet4U.com
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2)
Supply
Analog
Voltage (VCC)
Input Voltage
................................... –0.3V
(VIN+, VIN–).. –0.3V to (VCC +
to 6V
0.3V)
Reference Voltage (VREF) .............. –0.3V to (VCC + 0.3V)
Digital Voltage (VSDO, VSCK, VCS).. –0.3V to (VCC + 0.3V)
Storage Temperature Range................... –65°C to 150°C
Operating Temperature Range
LTC2452C ................................................ 0°C to 70°C
LTC2452I.............................................. –40°C to 85°C
PIN CONFIGURATION
TOP VIEW
SCK 1
8 SDO
GND 2
7 CS
REF 3 9 6 IN+
VCC 4
5 IN
DD8 PACKAGE
8-LEAD (3mm s 2mm) PLASTIC DFN
C/I GRADE TJMAX = 125°C, θJA = 76°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
TOP VIEW
SCK 1
GND 2
REF 3
VCC 4
8 SDO
7 CS
6 IN+
5 IN
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
C/I GRADE TJMAX = 125°C, θJA = 140°C/W
ORDER INFORMATION
Lead Free Finish
TAPE AND REEL (MINI) TAPE AND REEL
PART MARKING* PACKAGE DESCRIPTION
LTC2452CDDB#TRMPBF LTC2452CDDB#TRPBF LDNJ
8-Lead Plastic (3mm × 2mm) DFN
LTC2452IDDB#TRMPBF LTC2452IDDB#TRPBF LDNJ
8-Lead Plastic (3mm × 2mm) DFN
LTC2452CTS8#TRMPBF LTC2452CTS8#TRPBF LTDPK
8-Lead Plastic TSOT-23
LTC2452ITS8#TRMPBF LTC2452ITS8#TRPBF
LTDPK
8-Lead Plastic TSOT-23
TRM = 500 pieces. *Temperature grades are identified by a label on the shipping container.
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on 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/
TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Note 2)
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Resolution (No Missing Codes)
(Note 3)
l 16
Bits
Integral Nonlinearity
(Note 4)
l
1 10
LSB
Offset Error
l
2 10
LSB
Offset Error Drift
0.02 LSB/°C
Gain Error
l 0.01 0.02 % of FS
Gain Error Drift
0.02 LSB/°C
Transition Noise
Power Supply Rejection DC
2.2 μVRMS
80 dB
2452fb
2

No Preview Available !

www.DataSheet4U.com
LTC2452
ANALOG INPUTS AND REFERENCES The l denotes the specifications which apply over the full
operating temperature range, otherwise specifications are at TA = 25°C.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
VIN+ Positive Input Voltage Range
VIN– Negative Input Voltage Range
l0
l0
VCC V
VCC V
VREF
VOR+, VUR+
VOR–, VUR–
CIN
IDC_LEAK(IN+)
IDC_LEAK(IN–)
Reference Voltage Range
Overrange/Underrange Voltage, IN+
Overrange/Underrange Voltage, IN–
IN+, INSampling Capacitance
IN+ DC Leakage Current
INDC Leakage Current
VREF = 5V, VIN– = 2.5V (See Figure 3)
VREF = 5V, VIN+ = 2.5V (See Figure 3)
VIN = GND (Note 10)
VIN = VCC (Note 10)
VIN = GND (Note 10)
VIN = VCC (Note 10)
l 2.5
VCC
8
8
0.35
l –10
l –10
1
1
10
10
l –10
l –10
1
1
10
10
V
LSB
LSB
pF
nA
nA
nA
nA
IDC_LEAK(REF)
REF DC Leakage Current
VREF = 3V (Note 10)
l –10
1
10
nA
ICONV
Input Sampling Current (Note 5)
50 nA
POWER REQUIREMENTS The l denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
VCC Supply Voltage
ICC Supply Current
Conversion
Sleep
CS = GND (Note 6)
CS = VCC (Note 6)
l 2.7
l
l
5.5
800 1200
0.2 0.6
V
μA
μA
DIGITAL INPUTS AND DIGITAL OUTPUTS The l denotes the specifications which apply over the full
operating temperature range,otherwise specifications are at TA = 25°C. (Note 2)
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
VIH High Level Input Voltage
VIL Low Level Input Voltage
IIN Digital Input Current
CIN Digital Input Capacitance
VOH
High Level Output Voltage
IO = –800μA
VOL
Low Level Output Voltage
IO = 1.6mA
IOZ Hi-Z Output Leakage Current
l VCC – 0.3
l
l –10
l VCC – 0.5
l
l –10
10
0.3
10
0.4
10
V
V
μA
pF
V
V
μA
2452fb
3

No Preview Available !

LTC2452
www.DataSheet4U.com
TIMING CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature
range,otherwise specifications are at TA = 25°C.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
tCONV
Conversion Time
l 13
16.6
23
ms
fSCK SCK Frequency Range
l 2 MHz
tlSCK SCK Low Period
l 250
ns
thSCK
SCK High Period
t1
CS Falling Edge to SDO Low Z
(Notes 7, 8)
t2
CS Rising Edge to SDO High Z
(Notes 7, 8)
t3 CS Falling Edge to SCK Falling Edge
l 250
l0
l0
l 100
ns
100 ns
100 ns
ns
tKQ
SCK Falling Edge to SDO Valid
(Note 7)
l0
100 ns
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. VCC = 2.7V to 5.5V
unless otherwise specified.
VREFCM = VREF/2, FS = VREF
VIN = VIN+ – VIN–, –VREF ≤ VIN ≤ VREF; VINCM = (VIN+ + VIN–)/2.
Note 3. Guaranteed by design, not subject to test.
Note 4. Integral nonlinearity is defined as the deviation of a code from a
straight line passing through the actual endpoints of the transfer curve.
Guaranteed by design and test correlation.
Note 5: CS = VCC. A positive current is flowing into the DUT pin.
Note 6: SCK = VCC or GND. SDO is high impedance.
Note 7: See Figure 4.
Note 8: See Figure 5.
Note 9: Input sampling current is the average input current drawn from the
input sampling network while the LTC2452 is actively sampling the input.
Note 10: A positive current is flowing into the DUT pin.
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C, unless otherwise noted)
Integral Nonlinearity, VCC = 5V
3
2
1 TA = 90°C
0
TA = –45°C, 25°C
–1
–2
–3
–5 –4 –3 –2 –1 0 1 2 3 4 5
DIFFERENTIAL INPUT VOLTAGE (V)
2452 G01
Integral Nonlinearity, VCC = 3V
3
2
1
TA = –45°C, 25°C, 90°C
0
–1
–2
–3
–3
–2 –1 0 1 2
DIFFERENTIAL INPUT VOLTAGE (V)
3
2452 G02
Maximum INL vs Temperature
3
2
1 VCC = VREF = 5V, 4.1V, 3V
0
–1
–2
–3
–50 –25
0
25 50 75
TEMPERATURE (°C)
100
2452 G03
2452fb
4

No Preview Available !

www.DataSheet4U.com
LTC2452
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C, unless otherwise noted)
Offset Error vs Temperature
5
4
3
2
1
0 VCC = VREF = 5V
–1
–2 VCC = VREF = 4.1V
–3 VCC = VREF = 3V
–4
–5
–50 –25
0
25 50 75
TEMPERATURE (°C)
100
2452 G04
Gain Error vs Temperature
5
4 VCC = VREF = 3V
3
2
1 VCC = VREF = 4.1V
0
VCC = VREF = 5V
–1
–2
–3
–4
–5
–50 –25
0
25 50 75
TEMPERATURE (°C)
100
2452 G05
Transition Noise vs Temperature
10
9
8
7
6
5
4 VCC = 5V
3
2
VCC = 3V
1
0
–50 –25
0
25 50 75 100
TEMPERATURE (°C)
2452 G06
Conversion Mode Power Supply
Current vs Temperature
900
800
700 VCC = 5V
600
500 VCC = 3V
400
VCC = 4.1V
300
200
100
0
–50 –25
0
25 50 75 100
TEMPERATURE (°C)
2452 G07
Sleep Mode Power Supply
Current vs Temperature
250
Average Power Dissipation
vs Temperature, VCC = 3V
10000
200
VCC = 5V
150
100 VCC = 4.1V
50
VCC = 3V
0
–50 –25
0
25 50 75
TEMPERATURE (°C)
100
2452 G08
1000
100
10
25Hz OUTPUT SAMPLE RATE
10Hz OUTPUT SAMPLE RATE
1Hz OUTPUT SAMPLE RATE
0
–50 –25
0
25 50 75 100
TEMPERATURE (°C)
2452 G09
Power Supply Rejection
vs Frequency at VCC
0
–20
–40
–60
–80
–100
–120
1
10 100 1k 10k 100k 1M 10M
FREQUENCY AT VCC (Hz)
2452 G10
Conversion Time vs Temperature
21
20
19
VCC = 5V, 4.1V, 3V
18
17
16
15
14
–50 –25
0
25 50 75
TEMPERATURE (°C)
100
2452 G11
2452fb
5