General Description
The MAX1142/MAX1143 are 200ksps, 14-bit ADCs.
These serially interfaced ADCs connect directly to
SPITM, QSPITM, and MICROWIRETM devices without
external logic. They combine an input scaling network,
internal track/hold, a clock, +4.096V reference, and
three general-purpose digital output pins (for external
multiplexer or PGA control) in a 20-pin SSOP package.
The excellent dynamic performance (SINAD
81dB),
high-speed (200ksps), and low power (7.5mA) of these
ADCs, make them ideal for applications such as indus-
trial process control, instrumentation, and medical
applications. The MAX1142 accepts input signals of 0
to +12V (unipolar) or 12V (bipolar), while the
MAX1143 accepts input signals of 0 to +4.096V (unipo-
lar) or 4.096V (bipolar). Operating from a single
+4.75V to +5.25V analog supply and a +4.75V to
+5.25V digital supply, power-down modes reduce cur-
rent consumption to 1mA at 10ksps and further reduce
supply current to less than 20A at slower data rates.
A serial strobe output (SSTRB) allows direct connection
to the TMS320-family of digital signal processors. The
MAX1142/MAX1143 user can select either the internal
clock, or an external serial-interface clock for the ADC
to perform analog-to-digital conversions.
The MAX1142/MAX1143 feature internal calibration cir-
cuitry to correct linearity and offset errors. On-demand
calibration allows the user to optimize performance.
Three user-programmable logic outputs are provided
for the control of an 8-channel MUX or a PGA.
Applications
Industrial Process Control
Industrial I/O Modules
Data-Acquisition Systems
Medical Instruments
Portable and Battery-Powered Equipment
Features
o
200ksps (Bipolar) and 150ksps (Unipolar)
Sampling ADC
o
14-Bits, No Missing Codes
o
1LSB INL Guaranteed
o
81dB (min) SINAD
o
+5V Single-Supply Operation
o
Low Power Operation, 7.5mA (Unipolar Mode)
o
2.5A Shutdown Mode
o
Software-Configurable Unipolar & Bipolar Input
Ranges
0 to +12V and 12V (MAX1142)
0 to +4.096V and 4.096V (MAX1143)
Internal or External Reference
o
Internal or External Clock
o
SPI/QSPI/MICROWIRE-Compatible Wire Serial
Interface
o
Three User-Programmable Logic Outputs
o
Small 20-Pin SSOP Package
MAX1142/MAX1143
14-Bit ADC, 200ksps, +5V Single-Supply
with Reference
________________________________________________________________
Maxim Integrated Products
1
TOP VIEW
CS
SHDN
RST
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
AGND
AIN
CREF
AV
DD
AGND
REFADJ
REF
DIN
DV
DD
DGND
SCLK
P2
P1
P0
SSTRB
DGND
12
11
9
10
DOUT
MAX1142
MAX1143
SSOP
Pin Configuration
19-2037; Rev 0; 5/01
Ordering Information
PART
TEMP. RANGE
PIN-
PACKAGE
INL
(LSB)
MAX1142
ACAP
0
C to +70
C
20 SSOP
1
MAX1142BCAP
0
C to +70
C
20 SSOP
2
Functional Diagram appears at end of data sheet.
Typical Application Circuit appears at end of data sheet.
SPI and QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
Ordering Information continued at end of data sheet.
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
MAX1142/MAX1143
14-Bit ADC, 200ksps, +5V Single-Supply
with Reference
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
AV
DD
to AGND, DV
DD
to DGND .............................-0.3V to +6V
AGND to DGND.....................................................-0.3V to +0.3V
AIN to AGND.....................................................................16.5V
REFADJ, CREF, REF to AGND.................-0.3V to (AV
DD
+ 0.3V)
Digital Inputs to DGND.............................................-0.3V to +6V
Digital Outputs to DGND .........................-0.3V to (DV
DD
+ 0.3V)
Continuous Power Dissipation (T
A
= +70C)
20-SSOP (derate 8.00mW/C above +70C) ...............640mW
Operating Temperature Ranges
MAX114_CAP ......................................................0C to +70C
MAX114_EAP....................................................-40C to +85C
Storage Temperature Range .............................-60C to +150C
Junction Temperature ......................................................+150C
Lead Temperature (soldering, 10s) .................................+300C
ELECTRICAL CHARACTERISTICS
(AV
DD
= DV
DD
= +5V 5%, f
SCLK
= 4.8MHz, external clock (50% duty cycle), 24 clocks/conversion (200ksps), bipolar input, external
V
REF
= +4.096V, V
REFADJ
= AV
DD
, C
REF
= 2.2F, C
CREF
= 1F, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
T
A
= +25C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DC ACCURACY
(Note 1)
Resolution
14
Bits
Unipolar Mode
MAX114_A
1
Relative Accuracy (Note 2)
INL
MAX114_B
2
LSB
Differential Nonlinearity
DNL
Unipolar Mode
1
LSB
Transition Noise
0.34
LSB RMS
Unipolar
4
Offset Error
Bipolar
6
mV
Unipolar
0.2
Gain Error (Note 3)
Bipolar
0.3
%FSR
Offset D r i ft ( Bi p ol ar and U ni p ol ar )
Excluding reference drift
1
ppm/
o
C
G ai n D r i ft ( Bi p ol ar and U ni p ol ar )
Excluding reference drift
1
ppm/
o
C
DYNAMIC SPECIFICATIONS
(5kHz sine-wave input, 200ksps, 4.8MHz clock, bipolar input mode).
(MAX1142, 24Vp-p. MAX1143, 8.192Vp-p)
f
IN
= 5kHz
81
SINAD
f
IN
= 100kHz
82
dB
f
IN
= 5kHz
82
SNR
f
IN
= 100kHz
82
dB
f
IN
= 5kHz
-88
THD
f
IN
= 100kHz
91
dB
f
IN
= 5kHz
90
SFDR
f
IN
= 100kHz
95
dB
ANALOG INPUT
Unipolar
0
12
MAX1142
Bipolar
-12
12
Unipolar
0
4.096
Input Range
MAX1143
Bipolar
- 4.096
4.096
V
MAX1142/MAX1143
14-Bit ADC, 200ksps, +5V Single-Supply
with Reference
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(AV
DD
= DV
DD
= +5V 5%, f
SCLK
= 4.8MHz, external clock (50% duty cycle), 24 clocks/conversion (200ksps), bipolar input, external
V
REF
= +4.096V, V
REFADJ
= AV
DD
, C
REF
= 2.2F, C
CREF
= 1F, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
T
A
= +25C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Unipolar
7.5
10.0
MAX1142
Bipolar
5.9
7.9
Unipolar
100
1000
Input Impedance
MAX1143
Bipolar
3.4
4.5
k
Input Capacitance
32
pF
CONVERSION RATE
Internal Clock Frequency
4
MHz
Aperture Delay
t
AD
10
ns
Aperture Jitter
t
AJ
50
ps
MODE 1 (24 External Clock Cycles per Conversion)
Unipolar
0.1
3
External Clock Frequency
f
SCLK
Bipolar
0.1
4.8
MHz
Unipolar
4.17
125
Sample Rate
f
S
= f
SCLK
/24
Bipolar
4.17
200
ksps
Unipolar
8
240
Conversion Time (Note 4)
t
CONV+ACQ
=
24 / f
SCLK
Bipolar
5
240
s
MODE 2
(Internal Clock Mode)
External Clock Frequency
(Data Transfer Only)
8
MHz
Conversion Time
SSTRB Low Pulse Width
4
6
s
Unipolar
1.82
Acquisition Time
Bipolar
1.14
s
MODE 3
(32 External Clock Cycles per Conversion)
External Clock Frequency
f
SCLK
Unipolar or Bipolar
0.1
4.8
MHz
Sample Rate
f
S
= f
SCLK
/32
Unipolar or Bipolar
3.125
150
ksps
Conversion Time (Note 4)
t
CONV+ACQ
=
32 / f
SCLK
Unipolar or Bipolar
6.67
320
s
INTERNAL REFERENCE
Output Voltage
V
REF
4.056
4.096
4.136
V
REF Short Circuit Current
24
mA
Output Tempco
20
ppm/
o
C
Capacitive Bypass at REF
0.47
10
F
Maximum Capacitive Bypass at
REFADJ
10
F
REFADJ Output Voltage
4.096
V
REFADJ Input Range
For small adjustments from 4.096V
100
mV
MAX1142/MAX1143
14-Bit ADC, 200ksps, +5V Single-Supply
with Reference
4
_______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(AV
DD
= DV
DD
= +5V 5%, f
SCLK
= 4.8MHz, external clock (50% duty cycle), 24 clocks/conversion (200ksps), bipolar input, external
V
REF
= +4.096V, V
REFADJ
= AV
DD
, C
REF
= 2.2F, C
CREF
= 1F, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at
T
A
= +25C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
REFADJ Buffer Disable
Threshold
To power-down the internal reference
AV
DD
-
0.5V
AV
DD
-
0.1V
V
Buffer Voltage Gain
1
V/V
EXTERNAL REFERENCE (Reference buffer disabled. Reference applied to REF)
Input Range (Notes 5 and 6)
3.0
4.096
4.2
V
V
REF
= 4.096V, f
SCLK
= 4.8MHz
250
V
REF
= 4.096V, f
SCLK
= 0
230
Input Current
In power-down, f
SCLK
= 0
0.1
A
DIGITAL INPUTS
Input High Voltage
V
IH
2.4
V
Input Low Voltage
V
IL
0.8
V
Input Leakage
I
IN
V
IN
= 0 or DV
DD
1
A
Input Hysteresis
V
HYST
0.2
V
Input Capacitance
C
IN
10
pF
DIGITAL OUTPUTS
Output High Voltage
V
OH
I
SOURCE
= 0.5mA
DV
DD
-
0.5
V
I
SINK
= 5mA
0.4
Output Low Voltage
V
OL
I
SINK
= 16mA
0.8
V
Three-State Leakage Current
I
L
CS = DV
DD
10
A
Three-State Output
Capacitance
CS = DV
DD
10
pF
POWER SUPPLIES
Analog Supply (Note 7)
AV
DD
4.75
5
5.25
V
Digital Supply (Note 7)
DV
DD
4.75
5
5.25
V
Unipolar Mode
5
8
Bipolar Mode
8.5
11
mA
Analog Supply Current
I
ANALOG
SHDN = 0, or softw are power -down mode
0.3
10
A
Unipolar or Bipolar Mode
2.5
3.5
mA
Digital Supply Current
I
DIGITAL
SHDN = 0, or softw are power -down mode
2.2
10
A
Power Supply Rejection Ratio
(Note 8)
PSRR
AV
DD
= DV
DD
= 4.75V to 5.25V,
72
dB
MAX1142/MAX1143
14-Bit ADC, 200ksps, +5V Single-Supply
with Reference
_______________________________________________________________________________________
5
Note 1:
Tested at AV
DD
= DV
DD
= +5V, bipolar input mode.
Note 2:
Relative accuracy is the deviation of the analog value at any code from its theoretical value after the gain error and offset
error have been nulled.
Note 3:
Offset nulled.
Note 4:
Conversion time is defined as the number of clock cycles multiplied by the clock period, clock has 50% duty cycle.
Includes the acquisition time.
Note 5:
ADC performance is limited by the converter's noise floor, typically 300Vp-p.
Note 6
When an external reference has a different voltage than the specified typical value, the full scale of the ADC will scale
proportionally.
Note 7:
Electrical characteristics are guaranteed from AV
DD(MIN)
= DV
DD(MIN)
to AV
DD(MAX)
= DV
DD(MAX)
. For operations beyond
this range, see the
Typical Operating Characteristics. For guaranteed specifications beyond the limits, contact
the factory.
Note 8:
Defined as the change in positive full-scale caused by a 5% variation in the nominal supply voltage.
TIMING CHARACTERISTICS (Figures 5 and 6)
(AV
DD
= DV
DD
= +5V 5%, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNIT
Acquisition Time
t
ACQ
1.14
s
DIN to SCLK Setup
t
DS
50
ns
DIN to SCLK Hold
t
DH
0
ns
SCLK to DOUT Valid
t
DO
70
ns
CS Fall to DOUT Enable
t
DV
C
LOAD
= 50pF
80
ns
CS Rise to DOUT Disable
t
TR
C
LOAD
= 50pF
80
ns
CS to SCLK Rise Setup
t
CSS
100
ns
CS to SCLK Rise Hold
t
CSH
0
ns
SCLK High Pulse Width
t
CH
80
ns
SCLK Low Pulse Width
t
CL
80
ns
SCLK Fall to SSTRB
t
SSTRB
C
LOAD
= 50pF
80
ns
CS Fall to SSTRB Enable
t
SDV
C
LOAD
= 50pF, External clock mode
80
ns
CS Rise to SSTRB Disable
t
STR
C
LOAD
= 50pF, External clock mode
80
ns
SSTRB Rise to SCLK Rise
t
SCK
Internal clock mode
0
ns
RST Pulse Width
t
RS
208
ns
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