Rainbow Electronics MAX1031 User Manual

General Description

The MAX1027/MAX1029/MAX1031 are serial 10-bit ana­log-to-digital converters (ADCs) with an internal reference
and an internal temperature sensor. These devices fea­ture on-chip FIFO, scan mode, internal clock mode, inter­nal averaging, and AutoShutdown™. The maximum
sampling rate is 300ksps using an external clock. The
MAX1031 has 16 input channels, the MAX1029 has 12
input channels, and the MAX1027 has 8 input channels.
All input channels are configurable for single-ended or
differential inputs in unipolar or bipolar mode. All three
devices operate from a +5V supply and contain a 10MHz
SPI™/QSPI™/MICROWIRE™-compatible serial port.

The MAX1031 is available in 28-pin 5mm x 5mm QFN
with exposed pad and 24-pin QSOP packages. The
MAX1027/MAX1029 are only available in QSOP pack­ages. All three devices are specified over the extended

-40°C to +85°C temperature range.

________________________Applications

System Supervision

Data-Acquisition Systems

Industrial Control Systems

Patient Monitoring

Data Logging

Instrumentation

Features

♦ Internal Temperature Sensor (±1°C Accuracy)

♦ 16-Entry First-In/First-Out (FIFO)

♦ Analog Multiplexer with True Differential

Track/Hold

16-, 12-, 8-Channel Single Ended
8-, 6-, 4-Channel True Differential
(Unipolar or Bipolar)

♦ Accuracy: ±1 LSB INL, ±1 LSB DNL, No Missing

Codes Over Temperature

♦ Scan Mode, Internal Averaging, and Internal Clock

♦ Low-Power Single +3V Operation

1mA at 300ksps

♦ Internal 2.5V Reference or External Differential

Reference

♦ 10MHz 3-Wire SPI/QSPI/MICROWIRE-Compatible

Interface

♦ Space-Saving 28-Pin 5mm x 5mm QFN Package

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,

Temp Sensor, Internal Reference

________________________________________________________________ Maxim Integrated Products 1

Pin Configurations

19-2854; Rev 1; 7/03

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.

EVALUATION KIT

AVAILABLE

Ordering Information

*Future product—contact factory for availability.

Ordering Information continued at end of data sheet.

TOP VIEW

Pin Configurations continued at end of data sheet.

AutoShutdown is a trademark of Maxim Integrated Products, Inc.
SPI/QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.

PART TEMP RANGE PIN-PACKAGE

MAX1027ACEE-T* 0°C to +70°C 16 QSOP

MAX1027AEEE-T* -40°C to +85°C 16 QSOP

1

AIN0

AIN1

AIN2

AIN3

AIN4

AIN5

REF-/AIN6

CNVST/AIN7

1

2

3

MAX1027

4

5

6

7

8

QSOP

16

EOC

15

DOUT

14

DIN

13

CS

12

SCLK

V

11

DD

GND

10

REF+

9

AIN0

AIN1

AIN2

AIN4

AIN5

AIN6

AIN8

2

3

4

MAX1029

5

6

7

8

9

10

QSOP

20

EOC

19

DOUT

18

DIN

17

CSAIN3

16

SCLK

15

V

14

GND

REF+AIN7

13

12

CNVST/AIN11

11

REF-/AIN10AIN9

DD

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VDD= +2.7V to +3.6V, f

SAMPLE

= 300kHz, f

SCLK

= 4.8MHz (50% duty cycle), V

REF

= 2.5V, TA= T

MIN

to T

MAX

, unless otherwise

noted. Typical values are at T

A

= +25°C.)

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.

VDDto GND..............................................................-0.3V to +6V

CS, SCLK, DIN, EOC, DOUT to GND.........-0.3V to (V

DD

+ 0.3V)

AIN0–AIN13, REF-/AIN_, CNVST/AIN_,

REF+ to GND.........................................-0.3V to (V

DD

+ 0.3V)

Maximum Current into Any Pin............................................50mA

Continuous Power Dissipation (T

A

= +70°C)

16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW

20-Pin QSOP (derate 9.1mW/°C above +70°C)...........727mW

24-Pin QSOP (derate 9.5mW/°C above +70°C)...........762mW

28-Pin QFN 5mm x 5mm

(derate 20.8mW/°C above +70°C)........................1667mW

Operating Temperature Ranges

MAX10__C__.......................................................0°C to +70°C

MAX10__E__....................................................-40°C to +85°C

Storage Temperature Range .............................-60°C to +150°C

Junction Temperature......................................................+150°C

Lead Temperature (soldering, 10s) .................................+300°C

DC ACCURACY (Note 1)

Resolution RES 10 Bits

Integral Nonlinearity INL ±1.0 LSB

Differential Nonlinearity DNL No missing codes over temperature ±1.0 LSB

Offset Error ±0.5 ±2.0 LSB

Gain Error (Note 2) ±0.5 ±2.0 LSB

Offset Error Temperature
Coefficient

Gain Temperature Coefficient ±0.8 ppm/°C

Channel-to-Channel Offset
Matching

DYNAMIC SPECIFICATIONS (10kHz sine wave input, 2.5V

Signal-to-Noise Plus Distortion SINAD 70 dB

Total Harmonic Distortion THD Up to the 5th harmonic -82 dBc

Spurious-Free Dynamic Range SFDR 80 dBc

Intermodulation Distortion IMD f

Full-Power Bandwidth -3dB point 1 MHz

Full-Linear Bandwidth S / (N + D) > 68dB 25 kHz

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

= 9.9kHz, f

in1

, 300ksps, f

P-P

= 10.2kHz 76 dBc

in2

SCLK

= 4.8MHz)

±0.1 LSB

±2

ppm/°C

FSR

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,

Temp Sensor, Internal Reference

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +3.6V, f

SAMPLE

= 300kHz, f

SCLK

= 4.8MHz (50% duty cycle), V

REF

= 2.5V, TA= T

MIN

to T

MAX

, unless otherwise

noted. Typical values are at T

A

= +25°C.)

CONVERSION RATE

Power-Up Time t

Acquisition Time t

Conversion Time t

External Clock Frequency f

SCLK Duty Cycle 40 60 %

Aperture Delay 30 ns

Aperture Jitter <50 ps

ANALOG INPUT

Input Voltage Range

Input Leakage Current V

Input Capacitance During acquisition time (Note 6) 24 pF

INTERNAL TEMPERATURE SENSOR

Measurement Error (Note 7)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

PU

ACQ

CONV

SCLK

External reference 0.8

Internal reference (Note 3) 65

Internally clocked 3.5

Externally clocked (Note 4) 2.7

Externally clocked conversion 0.1 4.8

Data I/O 10

Unipolar 0 V

Bipolar (Note 5) - V

= V

IN

DD

Grade A, TA = +25°C ±0.3

Grade A, TA = -20°C to +85°C ±0.5 ±1

Grade A, TA = T

Grade B, TA = +25°C ±0.7

Grade B, T

A

= T

MIN

MIN

to T

to T

MAX

MAX

/ 2 V

RE F

±0.01 ±1 µA

±0.75 ±1.5

±1.2 ±2.5

0.6 µs

REF

/ 2

RE F

µs

µs

MHz

V

°C

Temperature Measurement Noise 0.1 °C

Temperature Resolution 1/8 °C

Power-Supply Rejection 0.3 °C/V

INTERNAL REFERENCE

REF Output Voltage 2.48 2.50 2.52 V

REF Temperature Coefficient TC

Output Resistance 6.5 kΩ

REF Output Noise 200 µV

REF Power-Supply Rejection PSRR -70 dB

EXTERNAL REFERENCE INPUT

REF- Input Voltage Range V

REF+ Input Voltage Range V

REF+ Input Current I

REF-

REF+

REF+

Grade A ±8

REF

Grade B ±30

V

V

REF+

REF+

= 2.5V, f

= 2.5V, f

= 300ksps 40 100

SAMPLE

= 0 ±0.1 ±5

SAMPLE

0 500 mV

1.0 VDD + 50mV V

RMS

ppm/°C

RMS

µA

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference

4 _______________________________________________________________________________________

Note 1: Tested at VDD= +2.7V, unipolar input mode.
Note 2: Offset nulled.
Note 3: Time for reference to power up and settle to within 1 LSB.
Note 4: Conversion time is defined as the number of clock cycles multiplied by the clock period; clock has 50% duty cycle.
Note 5: The operational input voltage range for each individual input of a differentially configured pair is from GND to V

DD

. The

operational input voltage difference is from -V

REF

/ 2 to +V

REF

/ 2.

Note 6: See Figure 3 (Input Equivalent Circuit) and the Sampling Error vs. Source Impedance curve in the Typical Operating

Characteristics section.

Note 7: Fast automated test, excludes self-heating effects.
Note 8: Supply current is specified depending on whether an internal or external reference is used for voltage conversions.

Temperature measurements always use the internal reference.

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +3.6V, f

SAMPLE

= 300kHz, f

SCLK

= 4.8MHz (50% duty cycle), V

REF

= 2.5V, TA= T

MIN

to T

MAX

, unless otherwise

noted. Typical values are at T

A

= +25°C.)

DIGITAL INPUTS (SCLK, DIN, CS, CNVST)

Input Voltage Low V

Input Voltage High V

Input Hysteresis V

Input Leakage Current I

Input Capacitance C
DIGITAL OUTPUTS (DOUT, EOC)

Output Voltage Low V

Output Voltage High V

Tri-State Leakage Current I

Tri-State Output Capacitance C

POWER REQUIREMENTS

Supply Voltage V

Supply Current (Note 8) I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Power-Supply Rejection PSR VDD = 2.7V to 3.6V; full-scale input ±0.2 ±1 mV

IL

IH

HYST

IN

IN

OL

OH

L

OUT

DD

DD

VIN = 0 or V

I

SINK

I

SINK

I

SOURCE

CS = V
CS = V

Internal
reference

External
reference

DD

= 2mA 0.4

= 4mA 0.8

= 1.5mA VDD - 0.5 V

DD

DD

During temp sense 2200 2700

f

SAMPLE

f

SAMPLE

Shutdown 0.2 5

During temp sense 1550 2000

f

SAMPLE

Shutdown 0.2 5

VDD x 0.7 V

2.7 3.6 V

= 300ksps 1550 1800

= 0, REF on 1000 1200

= 300ksps 880 1100

±0.01 ±1.0 µA

±0.05 ±1 µA

VDD x 0.3 V

200 mV

15 pF

15 pF

V

µA

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,

Temp Sensor, Internal Reference

_______________________________________________________________________________________ 5

Note 9: This time is defined as the number of clock cycles needed for conversion multiplied by the clock period. If the internal refer-

ence needs to be powered up, the total time is additive. The internal reference is always used for temperature measurements.

TIMING CHARACTERISTICS (Figure 1)

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0 256 512 768 1024

INTEGRAL NONLINEARITY

vs. OUTPUT CODE

MAX1027/29/31 toc01

OUTPUT CODE

INTEGRAL NONLINEARITY (LSB)

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0 256 512 768 1024

DIFFERENTIAL NONLINEARITY

vs. OUTPUT CODE

MAX1027/29/31 toc02

OUTPUT CODE

DIFFERENTIAL NONLINEARITY (LSB)

SINAD vs. FREQUENCY

MAX1027/29/31 toc03

FREQUENCY (kHz)

SINAD AMPLITUDE (dB)

100101

10

20

30

40

50

60

70

80

90

100

0

0.1 1000

Typical Operating Characteristics

(VDD= +3V, V

REF

= +2.5V, f

SCLK

= 4.8MHz, C

LOAD

= 30pF, TA= +25°C, unless otherwise noted.)

SCLK Clock Period t

SCLK Duty Cycle t

SCLK Fall to DOUT Transition t

CS Rise to DOUT Disable t
CS Fall to DOUT Enable t

DIN to SCLK Rise Setup t

SCLK Rise to DIN Hold t
CS to SCLK Rise Setup t
SCLK Rise to CS Hold t

CNVST Pulse Width

CS or CNVST Rise to EOC

Low (Note 9)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CP

CH

DOT

DOD

DOE

DS

DH

CSS

CSH

t

CSW

Externally clocked conversion 208

Data I/O 100

40 60 %

C

= 30pF 40 ns

LOAD

C

= 30pF 40 ns

LOAD

C

= 30pF 40 ns

LOAD

40 ns

0ns

40 ns

0ns

CKSEL = 00, CKSEL = 01 (temp sense) 40 ns

ns

CKSEL = 01 (voltage conversion) 1.4 µs

t

T S

t

R P

Temp sense 56

Voltage conversion 7

Reference power-up 65

µs

2.4974

2.4970

2.4982

2.4978

2.4986

2.4990

2.7 3.0 3.3 3.6

INTERNAL REFERENCE VOLTAGE

vs. SUPPLY VOLTAGE

MAX1027/29/31 toc10

SUPPLY VOLTAGE (V)

INTERNAL REFERENCE VOLTAGE (V)

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD= +3V, V

REF

= +2.5V, f

SCLK

= 4.8MHz, C

LOAD

= 30pF, TA= +25°C, unless otherwise noted.)

120

SFDR vs. FREQUENCY

100

80

60

40

SFDR AMPLITUDE (dB)

20

0

0.1 1000
FREQUENCY (kHz)

MAX1027/29/31 toc04

100101

SUPPLY CURRENT vs. SAMPLING RATE

700

600

500

400

SUPPLY CURRENT (µA)

300

200

1 1000

SAMPLING RATE (ksps)

10010

SHUTDOWN SUPPLY CURRENT

vs. SUPPLY VOLTAGE

0.5

0.4

0.3

0.2

0.1

SHUTDOWN SUPPLY CURRENT (µA)

MAX1027/29/31 toc07

SUPPLY CURRENT vs. SUPPLY VOLTAGE

700

650

MAX1027/29/31 toc05

600

SUPPLY CURRENT (µA)

550

500

2.7 3.6

SUPPLY CURRENT vs. TEMPERATURE

625

fS = 300ksps

620

615

SUPPLY CURRENT (µA)

610

MAX1027/29/31 toc06

3.33.0

SUPPLY VOLTAGE (V)

MAX1027/29/31 toc08

SHUTDOWN SUPPLY CURRENT (µA)

0

2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)

SHUTDOWN SUPPLY CURRENT

vs. TEMPERATURE

0.5

0.4

0.3

0.2

0.1

0

-40 10-15 35 60 85

TEMPERATURE (°C)

MAX1027/29/31 toc09

605

-40 10-15 35 60 85
TEMPERATURE (°C)

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,

Temp Sensor, Internal Reference

_______________________________________________________________________________________ 7

Typical Operating Characteristics (continued)

(VDD= +3V, V

REF

= +2.5V, f

SCLK

= 4.8MHz, C

LOAD

= 30pF, TA= +25°C, unless otherwise noted.)

-1.0

-0.5

0

0.5

1.0

0426810

SAMPLING ERROR

vs. SOURCE IMPEDANCE

MAX1027/29/31 toc17

SOURCE IMPEDANCE (kΩ)

SAMPLING ERROR (LSB)

INTERNAL REFERENCE VOLTAGE

vs. TEMPERATURE

2.510

2.506

2.502

2.498

2.494

INTERNAL REFERENCE VOLTAGE (V)

2.490

-40 10-15 35 60 85
TEMPERATURE (°C)

GAIN ERROR vs. SUPPLY VOLTAGE

0.6

0.4

0.2

GAIN ERROR (LSB)

0

MAX1027/29/31 toc11

0.6

0.5

0.4

0.3

0.2

OFFSET ERROR (LSB)

0.1

0

2.7 3.0 3.3 3.6

MAX1027/29/31 toc14

OFFSET ERROR

vs. SUPPLY VOLTAGE

SUPPLY VOLTAGE (V)

MAX1027/29/31 toc12

GAIN ERROR vs. TEMPERATURE

0.5

0.4

0.3

0.2

GAIN ERROR (LSB)

0.1

OFFSET ERROR

vs. TEMPERATURE

0.6

0.5

0.4

0.3

0.2

OFFSET ERROR (LSB)

0.1

0

-40 10-15 35 60 85
TEMPERATURE (°C)

MAX1027/29/31 toc15

MAX1027/29/31 toc13

-0.2

2.7 3.6

TEMPERATURE SENSOR ERROR

1.00

0.75

0.50

0.25

0

-0.25

-0.50

TEMPERATURE SENSOR ERROR (LSB)

-0.75

-1.00

-40 10-15 35 60 85

3.33.0

SUPPLY VOLTAGE (V)

vs. TEMPERATURE

GRADE A

GRADE B

TEMPERATURE (°C)

MAX1027/29/31 toc16

0

-40 -15 35 85
TEMPERATURE (°C)

6010

MAX1027/MAX1029/MAX1031

10-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference

8 _______________________________________________________________________________________

Pin Description

MAX1031

QFN

2–12, 26,

27, 28

——1–10 — AIN0–9 Analog Inputs

———1–6AIN0–5 Analog Inputs

13 15 ——REF-/AIN14

——11 — REF-/AIN10

——— 7 REF-/AIN6

14 16 ——

——12 —

——— 8

15 17 13 9 REF+ Positive Reference Input. Bypass to GND with a 0.1µF capacitor.

16 18 14 10 GND Ground

18 19 15 11 V

20 20 16 12 SCLK

MAX1031

QSOP

1–14 ——AIN0–13 Analog Inputs

MAX1029 MAX1027 NAME FUNCTION

Negative Input for External Differential Reference/Analog Input 14.
See Table 3 for details on programming the setup register.

Negative Input for External Differential Reference/Analog Input 10.
See Table 3 for details on programming the setup register.

Negative Input for External Differential Reference/Analog Input 6.
See Table 3 for details on programming the setup register.

CNVST/

AIN15

CNVST/

AIN11

CNVST/

AIN7

DD

Active-Low Conversion Start Input/Analog Input 15. See Table 3
for details on programming the setup register.

Active-Low Conversion Start Input/Analog Input 11. See Table 3
for details on programming the setup register.

Active-Low Conversion Start Input/Analog Input 7. See Table 3 for
details on programming the setup register.

Power Input. Bypass to GND with a 0.1µF capacitor.

Serial Clock Input. Clocks data in and out of the serial interface.
(Duty cycle must be 40% to 60%.) See Table 3 for details on
programming the clock mode.

21 21 17 13 CS

22 22 18 14 DIN

23 23 19 15 DOUT

24 24 20 16 EOC End of Conversion Output. Data is valid after EOC pulls low.

1, 17, 19,

25

———N.C. No Connection. Not internally connected.

Active-Low Chip Select Input. When CS is low, the serial interface
is enabled. When CS is high, DOUT is high impedance.

Serial Data Input. DIN data is latched into the serial interface on
the rising edge of SCLK.

Serial Data Output. Data is clocked out on the falling edge of
SCLK. High impedance when CS is connected to V

DD

.