MAX187BCPA+ Maxim, MAX187BCPA+ Datasheet
MAX187BCPA+
Specifications of MAX187BCPA+
Related parts for MAX187BCPA+
MAX187BCPA+ Summary of contents
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... BUFFER ENABLE/DISABLE MAX189 NOTE: PIN NUMBERS SHOWN ARE FOR 8-PIN DIPs ONLY. ™ SPI and QSPI are trademarks of Motorola. Microwire is a trademark of National Semiconductor. ________________________________________________________________ Maxim Integrated Products Call toll free 1-800-998-8800 for free samples or literature. ________________________________Features 12-Bit Resolution ± 1 ⁄ ...
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... DOUT Current ..................................................................±20mA 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 ...
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Low-Power, 12-Bit Serial ADCs ELECTRICAL CHARACTERISTICS (continued +5V ±5%; GND = 0V; unipolar input mode; 75ksps reference 4.096V, 4.7µF capacitor at REF pin, or MAX189—external reference: V REF capacitor at REF pin; T ...
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... SHDN Input Low Voltage V INSL SHDN Input Current I INS SHDN Input Mid Voltage V IM SHDN Voltage, Floating V FLT SHDN Maximum Allowed Leakage, Mid Input DIGITAL OUTPUT (DOUT) Output Voltage Low V OL Output Voltage High V OH Three-State Leakage Current I L Three-State Output ...
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... CONDITIONS CS = high (Note 7) MAX18_ _C 100pF LOAD MAX18_ 100pF LOAD C = 100pF LOAD is the maximum time the device takes to acquire the signal, and is also the minimum MIN TYP MAX UNITS 1.5 µs 20 150 ns 20 200 100 ns 100 ...
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Low-Power, 12-Bit Serial ADCs ________________________________________________Typical Operating Characteristics POWER-SUPPLY REJECTION vs. TEMPERATURE 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0 -60 - TEMPERATURE (°C) SUPPLY CURRENT vs. TEMPERATURE 2.2 1.8 MAX187 1.4 MAX189 1.0 0.6 0.2 -60 ...
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Low-Power, 12-Bit Serial ADCs _______________________________________________________________________Pin Description PIN NAME DIP WIDE AIN SHDN REF 5 — GND — 10 AGND — 11 DGND 6 12 DOUT ...
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Low-Power, 12-Bit Serial ADCs DOUT 3k DGND a. High and Figure 1. Load Circuits for DOUT Enable Time DOUT 3k DGND High-Z Figure 2. Load Circuits for ...
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Low-Power, 12-Bit Serial ADCs 4 SCLK 2 7 ANALOG INPUT MAX187 AIN +5V SHUTDOWN 3 6 SHDN DOUT INPUT OFF REF GND 4.7 F Figure ...
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... Figure 5. MAX187/MAX189 Shutdown Sequence 10 ______________________________________________________________________________________ Input Bandwidth ed by the 75ksps sample rate of the MAX187/MAX189. Therefore, the maximum sinusoidal input frequency allowed is 37.5kHz. Higher-frequency signals cause aliasing problems unless undersampling techniques are used. The MAX187 can be used with an internal or external ref- erence, while the MAX189 requires an external reference. ...
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Low-Power, 12-Bit Serial ADCs 10000 1000 MAX187 100 MAX189* 10 *REF CONNECTED 0 100 1000 10000 CONVERSIONS PER SECOND Figure 6. Average Supply Current vs. Conversion Rate ____________________Serial Interface Initialization After Power-Up and Starting ...
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Low-Power, 12-Bit Serial ADCs CS SCLK DOUT EOC CONVERSION INTERFACE IDLE EOC IN PROGRESS CONVERSION A/D TRACK 0 STATE 8 CONV MINIMUM CYCLE TIME Figure 8. MAX187/MAX189 Interface Timing Sequence CS t CS0 SCLK ...
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Low-Power, 12-Bit Serial ADCs OUTPUT CODE FULL-SCALE TRANSITION 11 111 11 110 11 101 00 011 00 010 00 001 00 000 INPUT VOLTAGE (LSBs) Figure 10. MAX187/MAX189 Unipolar Transfer Function, 4.096V = Full Scale ...
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Low-Power, 12-Bit Serial ADCs 12.2 12.0 11.8 11.6 11.4 11.2 11.0 10.8 10.6 10.4 (UNDERSAMPLED) 10 100 INPUT FREQUENCY (kHz) Figure 12. Effective Bits vs. Input Frequency The effective resolution (effective number of bits) the ADC provides ...
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... CPU generates the ser- ial clock. Choose a clock frequency up to 2.5MHz. 1. Use a general-purpose I/O line on the CPU to pull CS low. Keep SCLK low. 2. Wait the for the maximum conversion time specified before activating SCLK. Alternatively, look for a DOUT rising edge to determine the end of conversion. ...
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... When using SPI or QSPI, set CPOL = 0 and CPHA = 0. Conversion begins with a CS falling edge. DOUT goes low, indicating a conversion in progress. Wait until DOUT goes high or the maximum specified 8.5µs con- version time. Two consecutive 1-byte reads are required to get the full 12 bits from the ADC. DOUT out- put data transitions on SCLK’ ...
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Low-Power, 12-Bit Serial ADCs The ADC results are transmitted across a 1500V isola- tion barrier provided by three 6N136 opto-isolators. Isolated power must be supplied to the converter and the isolated side of the opto-couplers. 74HC595 three- state shift ...
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Low-Power, 12-Bit Serial ADCs __Ordering Information (continued) TEMP. RANGE PIN-PACKAGE ERROR PART MAX187AEPA -40°C to +85°C 8 Plastic DIP MAX187BEPA -40°C to +85°C 8 Plastic DIP MAX187CEPA -40°C to +85°C 8 Plastic DIP MAX187AEWE -40°C to +85°C 16 Wide ...
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Low-Power, 12-Bit Serial ADCs ___________________Chip Topography MAX187/MAX189 V SCLK DD AIN SHDN REF AGND 0.117" (2.97mm) TRANSISTOR COUNT: 2278; SUBSTRATE CONNECTED ______________________________________________________________________________________ CS 0.151" (3.84mm) DOUT DGND AGND 19 ...
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... E H 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. 20 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © ...