MAX1402EVKIT Maxim Integrated Products, MAX1402EVKIT Datasheet

no-image

MAX1402EVKIT

Manufacturer Part Number
MAX1402EVKIT
Description
EVAL KIT FOR MAX1402
Manufacturer
Maxim Integrated Products
Datasheets

Specifications of MAX1402EVKIT

Number Of Adc's
1
Number Of Bits
18
Sampling Rate (per Second)
480
Data Interface
Serial
Inputs Per Adc
6 Single Ended
Input Range
±VREF/2
Power (typ) @ Conditions
26.7mW @ 480SPS
Voltage Supply Source
Analog and Digital
Operating Temperature
0°C ~ 70°C
Utilized Ic / Part
MAX1402
Interface Type
SMA
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With/related Products
MAX1402
The MAX1402 low-power, multichannel, serial-output
analog-to-digital converter (ADC) features matched
200µA current sources for sensor excitation. This ADC
uses a sigma-delta modulator with a digital decimation
filter to achieve 16-bit accuracy. The digital filter’s user-
selectable decimation factor allows the conversion res-
olution to be reduced in exchange for a higher output
data rate. True 16-bit performance is achieved at an
output data rate of up to 480sps. In addition, the modu-
lator sampling frequency may be optimized for either
lowest power dissipation or highest throughput rate.
The MAX1402 operates from a +5V supply.
This device offers three fully differential input channels
that may be independently programmed with a gain
between +1V/V and +128V/V. Furthermore, it can com-
pensate an input-referred DC offset up to 117% of the
selected full-scale range. These three differential chan-
nels may also be configured to operate as five pseudo-
differential input channels. Two additional, fully
differential system-calibration channels are provided for
gain and offset error correction.
The MAX1402 may be configured to sequentially scan all
signal inputs and provide the results via the serial inter-
face with minimum communications overhead. When
used with a 2.4576MHz or 1.024MHz master clock, the
digital decimation filter can be programmed to produce
zeros in its frequency response at the line frequency and
associated harmonics, ensuring excellent line rejection
without the need for further post-filtering.
The MAX1402 is available in a 28-pin SSOP package.
19-1423; Rev 2; 1/07
SPI and QSPI are trademarks of Motorola, Inc.
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.
MAX1402CAI
MAX1402EAI
PART
Portable Industrial Instruments
Portable Weigh Scales
Loop-Powered Systems
Pressure Transducers
-40°C to +85°C
TEMP RANGE
0°C to +70°C
________________________________________________________________ Maxim Integrated Products
Ordering Information
General Description
+5V, 18-Bit, Low-Power, Multichannel,
PIN-
PACKAGE
28 SSOP
28 SSOP
Applications
Oversampling (Sigma-Delta) ADC
CODE
A28-2
A28-2
PKG
♦ 18-Bit Resolution, Sigma-Delta ADC
♦ 16-Bit Accuracy with No Missing Codes to 480sps
♦ Low Quiescent Current
♦ Matched On-Board Current Sources (200µA) for
♦ 3 Fully Differential or 5 Pseudo-Differential Signal
♦ 2 Additional, Fully Differential Calibration
♦ Programmable Gain and Offset
♦ Fully Differential Reference Inputs
♦ Converts Continuously or On Command
♦ Automatic Channel Scanning and Continuous
♦ Operates with +5V Analog Supply and +3V or +5V
♦ 3-Wire Serial Interface—SPI™/QSPI™ Compatible
♦ 28-Pin SSOP Package
Sensor Excitation
Input Channels
Channels/Auxiliary Input Channels
Data Output Mode
Digital Supply
TOP VIEW
250µA (operating mode)
2µA (power-down mode)
MUXOUT+
MUXOUT-
CLKOUT
RESET
CLKIN
AGND
OUT2
OUT1
AIN1
AIN2
AIN3
AIN4
CS
V+
10
11
12
13
14
1
2
3
4
5
6
7
8
9
MAX1402
SSOP
Pin Configuration
28
27
26
25
24
23
22
21
20
19
18
17
16
15
SCLK
DIN
DOUT
INT
V
DGND
CALOFF+
CALOFF-
REFIN+
REFIN-
CALGAIN+
CALGAIN-
AIN6
AIN5
DD
Features
1

Related parts for MAX1402EVKIT

MAX1402EVKIT Summary of contents

Page 1

... SSOP MAX1402EAI -40°C to +85°C 28 SSOP SPI and QSPI are trademarks of Motorola, Inc. ________________________________________________________________ Maxim Integrated Products 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. Oversampling (Sigma-Delta) ADC ♦ 18-Bit Resolution, Sigma-Delta ADC ♦ ...

Page 2

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC ABSOLUTE MAXIMUM RATINGS V+ to AGND, DGND .................................................-0. AGND, DGND ...............................................-0.3V to +6V DD AGND to DGND.....................................................-0.3V to +0.3V Analog Inputs to AGND................................-0.3V to (V+ + 0.3V) Analog Outputs ...

Page 3

Low-Power, Multichannel, ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL OFFSET DAC Offset DAC Range (Note 6) Offset DAC Resolution ...

Page 4

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL AIN and REFIN Input Sampling f S ...

Page 5

Low-Power, Multichannel, ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL POWER REQUIREMENTS V+ Voltage V Voltage V DD Power-Supply Rejection ...

Page 6

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC ELECTRICAL CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V wise noted. Typical values are +25°C.) A PARAMETER SYMBOL 5V Digital Supply Current ...

Page 7

Low-Power, Multichannel, Note 12: The input voltage range for the analog inputs is with respect to the voltage on the negative input of its respective differen- tial or pseudo-differential pair. Table 5 shows which inputs form differential pairs. ...

Page 8

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC TIMING CHARACTERISTICS (continued) (V+ = +5V ±5 +2.7V to +5.25V, AGND = DGND unless otherwise noted.) (Notes 19, 20, 21) PARAMETER SYMBOL CS Falling Edge to SCLK Falling t ...

Page 9

Low-Power, Multichannel, (V+ = +5V +5V +2.50V, REFIN- = AGND, f REFIN+ DD OUT1 AND OUT2 COMPLIANCE 250 200 150 100 COMPLIANCE VOLTAGE (V) V SUPPLY CURRENT ...

Page 10

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC (V+ = +5V +5V +2.50V, REFIN- = AGND REFIN+ V SUPPLY CURRENT vs. TEMPERATURE DD (240sps OUTPUT DATA RATE UNBUFFERED) 450 400 350 V DD 300 250 ...

Page 11

Low-Power, Multichannel, PIN NAME Clock Input. A crystal can be connected across CLKIN and CLKOUT. Alternatively, drive CLKIN with a 1 CLKIN CMOS-compatible clock at a nominal frequency of 2.4576MHz or 1.024MHz, and leave CLKOUT uncon- nected. Frequencies ...

Page 12

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC PIN NAME Negative Gain Calibration Input. Used for system-gain calibration. It forms the negative input of a fully differential input pair with CALGAIN+. Normally these inputs are connected to reference voltages in the ...

Page 13

Low-Power, Multichannel, _______________Detailed Description Circuit Description The MAX1402 is a low-power, multichannel, serial-output, sigma-delta ADC designed for applications with a wide dynamic range, such as weigh scales and pressure transducers. The functional block diagram in Figure 2 contains ...

Page 14

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC The MAX1402 can be configured to sequentially scan all signal inputs and to transmit the results through the serial interface with minimum communications over- head. The output word contains a result identification tag ...

Page 15

Low-Power, Multichannel, Selecting Clock Polarity The serial interface can be operated with the clock idling either high or low. This is compatible with Motorola’s SPI interface operated in CPOL = 1, CPHA = 1 or CPOL = 0, ...

Page 16

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC are held in reset, inhibiting normal self-timed operation. This bit may be used to convert on command to mini- mize the settling time to valid output data synchro- nize operation of ...

Page 17

Low-Power, Multichannel, pair. The exact sequence depends on the state of the DIFF bit (Table 4). When scanning, the calibration channels use the PGA gain, format, and DAC settings defined by the contents of Transfer Function Register 3. ...

Page 18

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 4. SCAN Mode Scanning Sequences (SCAN = 1) DIFF M1 M0 SEQUENCE AIN1–AIN6, AIN2–AIN6, AIN3–AIN6 AIN4–AIN6, AIN5–AIN6 AIN1–AIN6, AIN2–AIN6, AIN3–AIN6 AIN4–AIN6, AIN5–AIN6, CALOFF, CALGAIN AIN1–AIN6, AIN2–AIN6, ...

Page 19

Low-Power, Multichannel, Analog Inputs AIN1 to AIN6 Inputs AIN1 and AIN2 map to transfer-function register 1, regardless of scanning mode (SCAN = 1) or single- ended vs. differential (DIFF) modes. Likewise, AIN3 and AIN4 inputs always map to ...

Page 20

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 8. Transfer-Function Register Mapping—Normal Mode ( SCAN DIFF ...

Page 21

Low-Power, Multichannel, Table 9. Transfer-Function Register Mapping—Offset-Cal Mode ( SCAN DIFF ...

Page 22

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 10. Transfer-Function Register Mapping—Gain-Cal Mode ( SCAN DIFF ...

Page 23

Low-Power, Multichannel, DS1, DS0: The status of the auxiliary data input pins. These are latched on the first falling edge of the SCLK signal for the current data register read access. CID2–0: Channel ID tag (Table 11). Switching ...

Page 24

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC have low absolute temperature coefficients and tight TC matching. Optimized for transducer excitation, the current sources possess tight temperature tracking allowing accurate compensation of errors due to IR drops in long transducer cable ...

Page 25

Low-Power, Multichannel, Table 13c Values for Less than 16-Bit Gain Error in Unbuffered (BUFF = 0) EXT EXT Mode—4x Modulator Sampling Frequency (MF1, MF0 = 10 ); X2CLK = 0; CLKIN = 2.4576MHz PGA GAIN ...

Page 26

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 14 Values for Less than 16-Bit Gain Error in Buffered (BUFF = 1) EXT EXT Mode—All Modulator Sampling Frequencies (MF1, MF0 = XX); X2CLK = 0; CLKIN = 2.4576MHz ...

Page 27

Low-Power, Multichannel, Table 15. Modulator Operating Frequency, Sampling Frequency, and 16-Bit Data Output Rates MCLK MCLK FREQ. FREQ. X2CLK = 0 X2CLK = 1 DEFAULT f CLKIN f CLKIN (MHz) (MHz) 1.024 2.048 1.024 2.048 1.024 2.048 1.024 ...

Page 28

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 16b. MAX1402 Noise vs. Gain and Output Data Rate—Buffered Mode 2.5V 2.4576MHz REF CLKIN OUTPUT -3dB DATA FREQ. RATE (Hz) (sps 13.1 6.05 4.13 60 ...

Page 29

Low-Power, Multichannel, The noise shown in Table 16 is composed of device noise and quantization noise. The device noise is rela- tively low, but becomes the limiting noise source for high gain settings. The quantization noise is dependent ...

Page 30

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC when valid data is available, a minimum of three data- word periods later. The digital filter can be bypassed by setting the MDOUT bit in the global setup register. When MDOUT = 1, ...

Page 31

Low-Power, Multichannel, The digital filter does not provide any rejection close to the harmonics of the modulator sample frequency. However, due to the high oversampling ratio of the MAX1402, these bands occupy only a small fraction of the ...

Page 32

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC /* Assumptions: ** The MAX140X's CS pin is tied to ground ** The MAX140X's INT pin drives a falling-edge-triggered interrupt ** MAX140X's DIN is driven by MOSI, DOUT drives MISO, and SCLK drives ...

Page 33

Low-Power, Multichannel P3.0 8051 P3.1 Figure 14. MAX1402 to 8051 Interface /* Low-level function to write 8 bits ** The example shown here is for a bit-banging system with (CPOL=1, CPHA=1) */ void WriteByte (BYTE x) ...

Page 34

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC ANALOG SUPPLY REFIN+ R REF REFIN- ACTIVE R GAUGE SWITCHING AIN1 NETWORK AIN2 ADDITIONAL DUMMY R ANALOG GAUGE AND CALIBRATION CHANNELS OUT1 OUT2 Figure 16. Strain-Gauge Application with MAX1402 THERMOCOUPLE R JUNCTION AIN1 ...

Page 35

Low-Power, Multichannel, 4–20mA Loop-Powered Transmitters Low power, single-supply operation, and easy interfac- ing with optocouplers make the MAX1402 ideal for loop-powered 4–20mA transmitters. Loop-powered transmitters draw their power from the 4–20mA loop, limiting the transmitter circuitry to a ...

Page 36

Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC R L1 RTD Figure 19. 3-Wire RTD Application perature drift of the RTD current source and compen- sated for by the variation in the reference voltage. A common resistance ...

Page 37

Low-Power, Multichannel, +5V V+ 200µA OUT2 REFIN+ R REF REFIN- 200µA OUT1 AIN1 RTD PGA AIN2 AGND DGND Figure 20. 4-Wire RTD Application board is dedicated to ground planes while signals are placed on the solder side. Good ...

Page 38

... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 38 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products ...

Related keywords