MAX1402EVKIT Maxim Integrated Products, MAX1402EVKIT Datasheet
MAX1402EVKIT
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MAX1402EVKIT Summary of contents
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... 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 ♦ ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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. ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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, ...
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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 ...
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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. ...
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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, ...
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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 ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 8. Transfer-Function Register Mapping—Normal Mode ( SCAN DIFF ...
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Low-Power, Multichannel, Table 9. Transfer-Function Register Mapping—Offset-Cal Mode ( SCAN DIFF ...
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Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC Table 10. Transfer-Function Register Mapping—Gain-Cal Mode ( SCAN DIFF ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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, ...
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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 ...
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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 ...
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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) ...
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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 ...
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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 ...
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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 ...
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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 ...
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... 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 ...