LTC1852/LTC1853
8-Channel, 10-Bit/12-Bit,
400ksps, Low Power, Sampling ADCs
FEATURES
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DESCRIPTION
The 10-bit LTC
®
1852 and 12-bit LTC1853 are complete
8-channel data acquisition systems. They include a flexible
8-channel multiplexer, a 400ksps successive approxima-
tion analog-to-digital converter, an internal reference and a
parallel output interface. The multiplexer can be configured
for single-ended or differential inputs, two gain ranges and
unipolar or bipolar operation. The ADCs have a scan mode
that will repeatedly cycle through all 8 multiplexer channels
and can also be programmed to sequence through up to
16 addresses and configurations. The sequence can also
be read back from internal memory.
The reference and buffer amplifier provide pin strappable
ranges of 4.096V, 2.5V and 2.048V. The parallel output
includes the 10-bit or 12-bit conversion result plus the
4-bit multiplexer address. The digital outputs are pow-
ered from a separate supply allowing for easy interface
to 3V digital logic. Typical power consumption is 10mW
at 400ksps from a single 5V supply and 3mW at 250ksps
from a single 3V supply.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
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Flexible 8-Channel Multiplexer
Single-Ended or Differential Inputs
Two Gain Ranges
Unipolar or Bipolar Operation
Scan Mode and Programmable Sequencer
Eliminate Configuration Software Overhead
Low Power: 3mW at 250ksps
2.7V to 5.5V Supply Range
Internal or External Reference Operation
Parallel Output Includes MUX Address
Nap and Sleep Shutdown Modes
Pin Compatible up-grade 1.25Msps 10-Bit LTC1850
and 12-Bit LTC1851
APPLICATIONS
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High Speed Data Acquisition
Test and Measurement
Imaging Systems
Telecommunications
Industrial Process Control
Spectrum Analysis
BLOCK DIAGRAM
LTC1853
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
COM
2.5V
REFERENCE
8-CHANNEL
MULTIPLEXER
INTERNAL
CLOCK
CONTROL LOGIC
AND
PROGRAMMABLE
SEQUENCER
M1
SHDN
CS
CONVST
RD
WR
DIFF
A2
A1
A0
UNI/BIP
PGA
M0
OV
DD
BUSY
DIFF
OUT
/S6
A2
OUT
/S5
A1
OUT
/S4
A0
OUT
/S3
D11/S2
D10/S1
D9/S0
D8
D7
D6
D5
D4
D3
D2
D1
D0
OGND
18523 BD
Integral Linearity
1.0
0.5
INL ERROR (LSBs)
0
–0.5
REFOUT
+
–
12-BIT
SAMPLING
ADC
DATA
LATCHES
OUTPUT
DRIVERS
–1.0
0
REFIN
REF AMP
512 1024 1536 2048 2560 3072 3584 4096
CODE
1852 F01
REFCOMP
18523fa
1
LTC1852/LTC1853
ABSOLUTE MAXIMUM RATINGS
OV
DD
= V
DD
(Note 1, 2)
Supply Voltage (V
DD
) ..................................................6V
Analog Input Voltage (Note 3) ..... – 0.3V to (V
DD
+ 0.3V)
Digital Input Voltage (Note 4) .................... –0.3V to 10V
Digital Output Voltage ..................–0.3V to (V
DD
+ 0.3V)
Power Dissipation ...............................................500mW
Ambient Operating Temperature Range
LTC1852C/LTC1853C .............................. 0°C to 70°C
LTC1852I/LTC1853I............................. –40°C to 85°C
Storage Temperature Range...................–65°C to 150°C
Lead Temperature (Soldering, 10 sec) ................. 300°C
PIN CONFIGURATION
LTC1852
TOP VIEW
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
COM
1
2
3
4
5
6
7
8
9
48 M1
47
SHDN
46
CS
45
CONVST
44
RD
43
WR
42 DIFF
41 A2
40 A1
39 A0
38
UNI/BIP
37 PGA
36 M0
35 OV
DD
34 OGND
33
BUSY
32 NC
31 NC
30 D0
29 D1
28 D2
27 D3
26 D4
25 D5
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
COM
1
2
3
4
5
6
7
8
9
LTC1853
TOP VIEW
48 M1
47
SHDN
46
CS
45
CONVST
44
RD
43
WR
42 DIFF
41 A2
40 A1
39 A0
38
UNI/BIP
37 PGA
36 M0
35 OV
DD
34 OGND
33
BUSY
32 D0
31 D1
30 D2
29 D3
28 D4
27 D5
26 D6
25 D7
REFOUT 10
REFIN 11
REFCOMP 12
GND 13
V
DD
14
V
DD
15
GND 16
DIFF
OUT
/S6 17
A2
OUT
/S5 18
A1
OUT
/S4 19
A0
OUT
/S3 20
D9/S2 21
D8/S1 22
D7/S0 23
D6 24
REFOUT 10
REFIN 11
REFCOMP 12
GND 13
V
DD
14
V
DD
15
GND 16
DIFF
OUT
/S6 17
A2
OUT
/S5 18
A1
OUT
/S4 19
A0
OUT
/S3 20
D11/S2 21
D10/S1 22
D9/S0 23
D8 24
FW PACKAGE
48-LEAD PLASTIC TSSOP
FW PACKAGE
48-LEAD PLASTIC TSSOP
T
JMAX
= 150°C,
θ
JA
= 110°C/W
T
JMAX
= 150°C,
θ
JA
= 110°C/W
ORDER INFORMATION
LEAD FREE FINISH
LTC1852CFW#PBF
LTC1852IFW#PBF
LTC1853CFW#PBF
LTC1853IFW#PBF
TAPE AND REEL
LTC1852CFW#TRPBF
LTC1852IFW#TRPBF
LTC1853CFW#TRPBF
LTC1853IFW#TRPBF
PART MARKING
LTC1852CFW
LTC1852IFW
LTC1853CFW
LTC1853IFW
PACKAGE DESCRIPTION
48-Lead Plastic TSSOP (6.1mm)
48-Lead Plastic TSSOP (6.1mm)
48-Lead Plastic TSSOP (6.1mm)
48-Lead Plastic TSSOP (6.1mm)
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 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/
18523fa
2
LTC1852/LTC1853
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 2.7V to 5.5V, REFCOMP < V
DD
(Notes 5,6)
PARAMETER
Resolution (No Missing Codes)
Integral Linearity Error
Differential Linearity Error
Offset Error (Bipolar and Unipolar)
Gain = 1 (PGA = 1)
Gain = 2 (PGA = 0)
Offset Error Match (Bipolar and Unipolar)
Unipolar Gain Error
Gain = 1 (PGA = 1)
Gain = 2 (PGA = 0)
Unipolar Gain Error Match
Bipolar Gain Error
Gain = 1 (PGA = 1)
Gain = 2 (PGA = 0)
Bipolar Gain Error Match
Unipolar Gain Error
Gain = 1 (PGA = 1)
Gain = 2 (PGA = 0)
Bipolar Gain Error
Gain = 1 (PGA = 1)
Gain = 2 (PGA = 0)
Full-Scale Error Temperature Coefficient
With External 2.5V Reference
Applied to REFCOMP
V
DD
= 2.7V to 5.5V, f
S
≤ 250kHz
With External 2.5V Reference
Applied to REFCOMP
V
DD
= 2.7V to 5.5V, f
S
≤ 250kHz
l
l
l
l
CONVERTER CHARACTERISTICS
CONDITIONS
MIN
l
LTC1852
TYP
±0.25
±0.25
±0.5
±1
MAX
±1
±1
±2
±4
±0.5
MIN
12
LTC1853
TYP
±0.35
±0.25
±1
±2
MAX
±1
±1
±6
±12
±1
±4
±8
±1
±4
±8
±1
UNITS
Bits
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
ppm/°C
10
(Note 7)
(Note 8)
REFCOMP ≥ 2V
l
l
l
l
With External 4.096V Reference
Applied to REFCOMP (Note 12)
V
DD
= 4.75V to 5.25V, f
S
≤ 400kHz
With External 4.096V Reference
Applied to REFCOMP (Note 12)
V
DD
= 4.75V to 5.25V, f
S
≤ 400kHz
±2
±4
±0.5
±2
±4
±0.5
±1
±2
±1
±2
15
±3
±6
±3
±6
±1.5
±3
±1.5
±3
15
±8
±16
±8
±16
The
l
denotes the specifications which apply over the full operating temperature range, otherwise
specifications are at T
A
= 25°C. (Notes 5)
SYMBOL
V
IN
PARAMETER
Analog Input Range (Note 9)
Unipolar, Gain = 1 (PGA = 1)
Unipolar, Gain = 2 (PGA = 0)
Bipolar, Gain = 1 (PGA = 1)
Bipolar, Gain = 2 (PGA = 0)
Analog Input Leakage Current
Analog Input Capacitance
Between Conversions (Gain = 1)
Between Conversions (Gain = 2)
During Conversions
CONDITIONS
2.7V ≤ V
DD
≤ 5.5V, REFCOMP ≤ V
DD
0 – REFCOMP
0 – REFCOMP/2
± REFCOMP/2
±REFCOMP/4
l
ANALOG INPUT
MIN
TYP
MAX
UNITS
V
V
V
V
I
IN
C
IN
±1
15
25
5
50
50
150
150
μA
pF
pF
pF
ns
ns
ns
ps
RMS
dB
t
ACQ
t
S(MUX)
t
AP
t
jitter
CMRR
Sample-and-Hold Acquisition Time
Multiplexer Settling Time (Includes t
ACQ
)
Sample-and-Hold Aperture Delay Time
Sample-and-Hold Aperture Delay Time Jitter
Analog Input Common Mode Rejection Ratio
V
DD
= 5V
V
DD
= 5V
– 0.5
2
60
DYNAMIC ACCURACY
SYMBOL
S/(N + D)
THD
SFDR
PARAMETER
Total Harmonic Distortion
Spurious Free Dynamic Range
T
A
= 25°C. (Notes 5)
CONDITIONS
40kHz Input Signal
40kHz Input Signal, First 5 Harmonics
40kHz Input Signal
MIN
TYP
72.5
–80
–85
MAX
UNITS
dB
dB
dB
18523fa
Signal-to-Noise Plus Distortion Ratio
3
LTC1852/LTC1853
INTERNAL REFERENCE
PARAMETER
REFOUT Output Voltage
REFOUT Output Temperature Coefficient
REFOUT Line Regulation
Reference Buffer Gain
REFCOMP Output Voltage
REFCOMP Impedance
External 2.5V Reference (V
DD
= 5V)
Internal 2.5V Reference (V
DD
= 5V)
Impedance to GND, REFIN = V
DD
T
A
= 25°C. (Notes 5, 6)
CONDITIONS
I
OUT
= 0
I
OUT
= 0
2.7 ≤ V
DD
≤ 5.5, I
OUT
= 0
1.6368
4.092
4.060
MIN
2.48
TYP
2.50
±15
0.01
1.6384
4.096
4.096
19.2
1.6400
4.100
4.132
MAX
2.52
UNITS
V
ppm/°C
LSB/V
V/V
V
V
kΩ
The
●
denotes the specifications which apply over the full
operating temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 5V (Note 5)
SYMBOL
V
IH
V
IL
I
IN
C
IN
V
OH
V
OL
I
OZ
C
OZ
I
SOURCE
I
SINK
PARAMETER
High Level Input Voltage
Low Level Input Voltage
Digital Input Current
Digital Input Capacitance
High Level Output Voltage
Low Level Output Voltage
V
DD
= 4.75V, I
O
= –10μA
V
DD
= 4.75V, I
O
= – 200μA
V
DD
= 4.75V, I
O
= 160μA
V
DD
= 4.75V, I
O
= 1.6mA
CS
High (Note 9)
V
OUT
= 0V
V
OUT
= V
DD
●
●
●
●
DIGITAL INPUTS AND DIGITAL OUTPUTS
CONDITIONS
V
DD
= 5.25V
V
DD
= 4.75V
V
IN
= 0V to V
DD
MIN
●
●
●
TYP
MAX
0.8
±5
UNITS
V
V
μA
pF
V
V
2.4
1.5
4.5
4
0.5
0.10
0.4
±10
15
–20
30
V
V
μA
pF
mA
mA
Hi-Z Output Leakage D11 to D0, A0, A1, A2
OUT
, DIFF
OUT
V
OUT
= 0V to V
DD
,
CS
High
Hi-Z Capacitance D11 to D0
Output Source Current
Output Sink Current
The
●
denotes the specifications which apply over the full
operating temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 5V (Note 5)
SYMBOL
V
IH
V
IL
I
IN
C
IN
V
OH
V
OL
I
OZ
C
OZ
I
SOURCE
I
SINK
PARAMETER
High Level Input Voltage
Low Level Input Voltage
Digital Input Current
Digital Input Capacitance
High Level Output Voltage
Low Level Output Voltage
V
DD
= 2.7V, I
O
= –10μA
V
DD
= 2.7V, I
O
= – 200μA
V
DD
= 2.7V, I
O
= 160μA
V
DD
= 2.7V, I
O
= 1.6mA
CS
High (Note 9)
V
OUT
= 0V
V
OUT
= V
DD
●
●
●
●
DIGITAL INPUTS AND DIGITAL OUTPUTS
CONDITIONS
V
DD
= 3.3V
V
DD
= 2.7V
V
IN
= 0V to V
DD
MIN
●
●
●
TYP
MAX
0.45
±5
UNITS
V
V
μA
pF
V
V
1.9
1.5
2.5
2
0.05
0.10
0.4
±10
15
–10
15
V
V
μA
pF
mA
mA
Hi-Z Output Leakage D11 to D0, A0, A1, A2
OUT
, DIFF
OUT
V
OUT
= 0V to V
DD
,
CS
High
Hi-Z Capacitance D11 to D0
Output Source Current
Output Sink Current
18523fa
4
LTC1852/LTC1853
POWER REQUIREMENTS
SYMBOL
V
DD
OV
DD
I
DD
P
DISS
I
DDPD
PARAMETER
Analog Positive Supply Voltage
Output Positive Supply Voltage
Positive Supply Current
Power Dissipation
Power Down Positive Supply Current
Nap Mode
Sleep Mode
Power Down Power Dissipation
Nap Mode
Sleep Mode
Power Down Power Dissipation
Nap Mode
Sleep Mode
The
●
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 5)
CONDITIONS
(Note 10)
(Note 10)
V
DD
= OV
DD
= 5V, f
S
= 400kHz
V
DD
= OV
DD
= 2.7V, f
S
= 250kHz
V
DD
= OV
DD
= 5V, f
S
= 400kHz
V
DD
= OV
DD
= 2.7V, f
S
= 250kHz
SHDN
= Low,
CS
= Low
SHDN
= Low,
CS
= High
V
DD
= V
DD
= OV
DD
= 5V, f
S
= 400kHz
SHDN
= Low,
CS
= Low
SHDN
= Low,
CS
= High
V
DD
= V
DD
= OV
DD
= 3V, f
S
= 250kHz
SHDN
= Low,
CS
= Low
SHDN
= Low,
CS
= High
●
●
●
●
●
●
MIN
2.7
2.7
TYP
MAX
5.5
5.5
UNITS
V
V
mA
mA
mW
mW
mA
μA
mW
mW
mW
mW
2
0.83
10
2.25
0.5
20
2.5
0.1
1.5
0.06
3
1.33
15
4
The
●
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 5)
SYMBOL
f
SAMPLE(MAX)
PARAMETER
Maximum Sampling Frequency
Acquisition + Conversion
t
CONV
t
ACQ
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
Conversion Time
Acquisition Time
CS
to
RD
Setup Time
CS
to
CONVST
Setup Time
CS
to
SHDN
Setup Time
SHDN
to
CONVST
Wake-Up Time
CONVST
Low Time
CONVST
to
BUSY
Delay
Data Ready Before
BUSY
●
TIMING CHARACTERISTICS
CONDITIONS
V
DD
= 5.5V
V
DD
= 2.7V
V
DD
= 5.5V
V
DD
= 2.7V
V
DD
= 5.5V
V
DD
= 2.7V
(Note 13)
(Notes 9, 10)
(Notes 9, 10)
(Notes 9, 10)
Nap Mode (Note 10)
Sleep Mode (Note 10)
(Notes 10, 11)
C
L
= 25pF
●
●
●
●
●
●
●
●
●
●
●
MIN
400
250
TYP
MAX
UNITS
kHz
kHz
2.5
4.0
2.0
3.5
150
0
10
200
200
10
50
10
60
20
15
50
–5
20
35
45
45
60
30
35
40
35
μs
μs
μs
μs
ns
ns
ns
ns
ns
ms
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
18523fa
Delay Between Conversions
Wait Time
RD
After
BUSY
Data Access Time After
RD
(Note 10)
●
●
C
L
= 25pF
C
L
= 100pF
●
25
●
t
11
BUS Relinquish Time
0°C to 70°C
– 40°C to 85°C
●
●
●
10
t
12
RD
Low Time
t
10
5