MX7705EUE+ Maxim Integrated Products, MX7705EUE+ Datasheet
MX7705EUE+
Specifications of MX7705EUE+
Related parts for MX7705EUE+
MX7705EUE+ Summary of contents
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... PGA from 1 to 128 o Single (2.7V to 3.6V) or (4.75V to 5.25V) Supply o Low Power 1mW (max), 3V Supply 2μA (typ) Power-Down Current o SPI-/QSPI-/MICROWIRE-Compatible 3-Wire Serial Interface PART MX7705EUE+ + Denotes a lead(Pb)-free/RoHS-compliant package. Applications TOP VIEW Sigma-Delta ADC Features Ordering Information TEMP RANGE PIN- PACKAGE -40° ...
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Low-Power, 2-Channel, Sigma-Delta ADC ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V DD All Other Pins to GND.................................-0. Maximum Current Input into Any Pin ..................................50mA Continuous Power Dissipation (T = +70°C) A TSSOP (derate 9.4mW/°C above ...
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ELECTRICAL CHARACTERISTICS (continued 5V, GND = 1.225V for V DD REF+ 2.4576MHz, CLKDIV bit = GND = 0.1µF, C REF+ PARAMETER SYMBOL AIN Input Capacitance AIN Input Sampling Rate Input ...
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Low-Power, 2-Channel, Sigma-Delta ADC ELECTRICAL CHARACTERISTICS (continued 5V, GND = 1.225V for V DD REF+ 2.4576MHz, CLKDIV bit = GND = 0.1µF, C REF+ PARAMETER SYMBOL CLKIN INPUT CLKIN ...
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ELECTRICAL CHARACTERISTICS (continued 5V, GND = 1.225V for V DD REF+ 2.4576MHz, CLKDIV bit = GND = 0.1µF, C REF+ PARAMETER SYMBOL POWER REQUIREMENTS Power-Supply Voltage Power-Supply Current (Note 12) ...
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Low-Power, 2-Channel, Sigma-Delta ADC TIMING CHARACTERISTICS ( 5V, GND = 1.225V for V DD REF+ 2.4576MHz, CLKDIV bit = GND = 0.1µF, C REF+ (Figures 8, 9) PARAMETER SYMBOL DRDY ...
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TIMING CHARACTERISTICS (continued 5V, GND = 1.225V for V DD REF+ 2.4576MHz, CLKDIV bit = GND = 0.1µF, C REF+ (Figures 8, 9) Note 1: These errors are in the ...
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Low-Power, 2-Channel, Sigma-Delta ADC Table 1. Output RMS Noise vs. Gain and Output Data Rate (V FILTER FIRST -3dB FREQUENCY NOTCH AND OUTPUT DATA RATE BUFFERED (f = 1MHz) CLKIN 20Hz 5.24Hz 25Hz 6.55Hz 100Hz 26.2Hz 200Hz 52.4Hz UNBUFFERED ...
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Table 2. Peak-to-Peak Resolution vs. Gain and Output Data Rate (V FILTER FIRST NOTCH AND -3dB FREQUENCY OUTPUT DATA RATE BUFFERED (f = 1MHz) CLKIN 20Hz 5.24Hz 25Hz 6.55Hz 100Hz 26.2Hz 200Hz 52.4Hz UNBUFFERED (f = 1MHz) CLKIN 20Hz 5.24Hz ...
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Low-Power, 2-Channel, Sigma-Delta ADC Table 3. Output RMS Noise vs. Gain and Output Data Rate (V FILTER FIRST NOTCH AND -3dB FREQUENCY OUTPUT DATA RATE BUFFERED (f = 1MHz) CLKIN 20Hz 5.24Hz 25Hz 6.55Hz 100Hz 26.2Hz 200Hz 52.4Hz UNBUFFERED ...
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Table 4. Peak-to-Peak Resolution vs. Gain and Output Data Rate (V FILTER FIRST NOTCH AND -3dB FREQUENCY OUTPUT DATA RATE BUFFERED (f = 1MHz) CLKIN 20Hz 5.24Hz 25Hz 6.55Hz 100Hz 26.2Hz 200Hz 52.4Hz UNBUFFERED (f = 1MHz) CLKIN 20Hz 5.24Hz ...
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Low-Power, 2-Channel, Sigma-Delta ADC ( 5V 1.225V for V DD REF+ DD OFFSET ERROR vs. SUPPLY VOLTAGE (5V) 0.003 0.002 0.001 0 -0.001 -0.002 -0.003 4.75 4.85 4.95 5.05 5.15 ...
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V = 1.225V for V DD REF+ DD SUPPLY CURRENT vs. SUPPLY VOLTAGE (3V) 0.6 A 0 0.3 E 0.2 2.70 2.85 3.00 3.15 SUPPLY VOLTAGE (V) A: BUFFERED MODE B: ...
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Low-Power, 2-Channel, Sigma-Delta ADC ( 5V 1.225V for V DD REF+ DD SUPPLY CURRENT vs 0.5 0 0.3 E 0.2 0.4 0.6 0.8 1.0 1.2 ...
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V = 1.225V for V DD REF+ DD POWER-DOWN SUPPLY CURRENT vs. SUPPLY VOLTAGE (3V) 100 2.70 2.85 3.00 3.15 3.30 3.45 3.60 SUPPLY VOLTAGE (V) ...
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Low-Power, 2-Channel, Sigma-Delta ADC PIN NAME Serial Clock Input. Apply an external serial clock to transfer data to and from the device at data rates 1 SCLK 5MHz. Clock Input. Connect a crystal/resonator between CLKIN and ...
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AIN1+ AIN1- SWITCHING NETWORK AIN2+ AIN2- S1 AND S2 ARE OPEN IN BUFFERED MODE AND CLOSED IN UNBUFFERED MODE REF+ REF- Detailed Description The MX7705 low-power, 2-channel, serial-output ADC uses a sigma-delta modulator with a digital filter to achieve 16-bit ...
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Low-Power, 2-Channel, Sigma-Delta ADC To minimize gain errors in unbuffered mode, select a source impedance less than the maximum values shown in Figures 2 and 3. These are the maximum external resistance/capacitance combinations allowed before gain errors greater than ...
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Table 5. Input Sampling Capacitor vs. Gain GAIN INPUT SAMPLING CAPACITOR (C 1 3. 8–128 30 Increasing the gain increases the resolution of the ADC (LSB size decreases), but reduces the differential input voltage range. Calculate ...
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Low-Power, 2-Channel, Sigma-Delta ADC The MX7705 performs analog-to-digital conversions using a single-bit, 2nd-order, switched-capacitor, sigma-delta modulator. The sigma-delta modulation converts the input signal into a digital pulse train whose average duty cycle represents the digitized signal infor- mation. A ...
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External Oscillator The oscillator requires time to stabilize when enabled. Startup time for the oscillator depends on supply voltage, temperature, load capacitances, and center frequency. Depending on the load capacitance, a 1MΩ feedback resistor across the crystal can reduce the ...
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Low-Power, 2-Channel, Sigma-Delta ADC DIN RS2 RS1 RS0 COMMUNICATIONS REGISTER SETUP REGISTER (8 BITS) CLOCK REGISTER (8 BITS) DATA REGISTER (16 BITS) DOUT TEST REGISTER (8 BITS)* OFFSET REGISTER (24 BITS) GAIN REGISTER (24 BITS) *THE TEST REGISTER IS ...
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Table 6. Communications Register FIRST BIT (MSB) COMMUNICATION FUNCTION START/DATA READY Name 0/DRDY Defaults 0 Table 7. Register Selection RS2 RS1 RS0 ...
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Low-Power, 2-Channel, Sigma-Delta ADC Table 10. Operating-Mode Selection MD1 MD0 0 0 Normal Mode. Use this mode to perform normal conversions on the selected analog input channel. Self-Calibration Mode. This mode performs self-calibration on the selected channel determined from ...
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This register is reserved for factory testing of the device. For proper operation of the MX7705, do not change this register from its default power-on reset values. Offset and Gain-Calibration Registers The MX7705 contains one offset register and one gain ...
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Low-Power, 2-Channel, Sigma-Delta ADC Drive RESET low to reset the MX7705 to power-on reset status. DRDY goes high and all communication to the MX7705 is ignored while RESET is low. Upon releasing RESET, the device must be reconfigured to ...
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POLL DRDY OUTPUT 1 (DATA NOT READY) 0 (DATA READY) Figure 11. Sample Flow Diagram for Data Conversion ______________________________________________________________________________________ 16-Bit, Low-Power, 2-Channel, POWER-ON RESET INITIALIZE μC/μP SERIAL PORT WRITE TO THE COMMUNICATIONS REGISTER. SELECT CHANNEL 1 AND SET NEXT OPERATION ...
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Low-Power, 2-Channel, Sigma-Delta ADC When FSYNC = 1, the digital filter and analog modula- tor are in a reset state, inhibiting normal operation. Set FSYNC = 0 to begin calibration or conversion. When configured for normal operation (MD0 and ...
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Next, an internally generated voltage (V applied across AIN+ and AIN-. This condition results in the full-scale calibration. Start self-calibration by setting MD1 = 0, MD0 = 1, and FSYNC = 0 in the setup register. Self-calibration com- pletes in ...
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Low-Power, 2-Channel, Sigma-Delta ADC Applications Information Applications Examples Strain-Gauge Measurement Connect the differential inputs of the MX7705 to the bridge network of the strain gauge. In Figure 12, the ana- log positive supply voltage powers the bridge network and ...
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Integral Nonlinearity Integral nonlinearity (INL) is the deviation of the values on an actual transfer function from a straight line. This straight line is either a best-straight-line fit or a line drawn between the endpoints of the transfer function, once ...
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Low-Power, 2-Channel, Sigma-Delta ADC Chip Information TRANSISTOR COUNT: 42,000 PROCESS: BiCMOS 32 ______________________________________________________________________________________ Package Information For the latest package outline information and land patterns www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 33 © 2010 Maxim Integrated Products ...