MAX187BEWE-T Maxim Integrated, MAX187BEWE-T Datasheet
MAX187BEWE-T
Specifications of MAX187BEWE-T
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MAX187BEWE-T Summary of contents
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Low-Power, 12-Bit Serial ADCs General Description The MAX187/MAX189 serial 12-bit analog-to-digital con- verters (ADCs) operate from a single +5V supply and accept analog input. Both parts feature an 8.5Fs successive-approximation ADC, a fast track/hold (1.5Fs), ...
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... Harmonic) Spurious-Free Dynamic Range Small-Signal Bandwidth Full-Power Bandwidth CONVERSION RATE Conversion Time Track/Hold Acquisition Time Throughput Rate Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs Continuous Power Dissipation (T + 0.3V) 8-Pin PDIP (derate 9.1mW/NC above +70NC)..............727mW DD + 0.3V) 16-Pin Wide SO (derate 14.5mW/NC above 70NC).....1157mW DD + 0.3V) ...
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... SHDN Input High Voltage SHDN Input Low Voltage SHDN Input Current SHDN Input Mid voltage SHDN Voltage, Floating SHDN Maximum Allowed Leakage, Mid-Input Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs = 4.0MHz, external clock (50% duty cycle); MAX187—internal refer- CLK SYMBOL CONDITIONS t APR ...
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... Note 5: External load should not change during conversion for specified ADC accuracy. Note 6: DC test, measured at 4.75V and 5.25V only. Note 7: To guarantee acquisition time, t time needed for the signal to be acquired. Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs = 4.0MHz, external clock (50% duty cycle); MAX187—internal refer- CLK ...
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... TEMPERATURE 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0 -60 -20 20 TEMPERATURE (°C) SUPPLY vs. TEMPERATURE 2.2 1.8 MAX187 1.4 MAX189 1.0 0.6 0.2 -60 -20 20 TEMPERATURE (°C) Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs Typical Operating Characteristics 60 100 140 60 100 140 MAX187/MAX189 V vs. TEMPERATURE REF 4.090 4.089 4.088 4.087 4.086 4.085 4.084 4.083 4.082 4.081 4.080 -60 -20 20 ...
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... REF 5 — GND — 10 AGND — 11 DGND 6 12 DOUT SCLK — N.C. 9, 13. 14 Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs V SCLK 8 MAX187 N. MAX189 DOUT 6 N.C. GND 5 N.C. PDIP SHDN 6 N.C. REF 8 Supply Voltage. +5V, Q5% Sampling Analog Input REF Three-Level Shutdown Input. Pulling SHDN low shuts the MAX187/MAX189 down to 10FA (max) supply current ...
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... Figure 1. Load Circuits for DOUT Enable Time DOUT 3kI Figure 2. Load Circuits for DOUT Disable Time Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs A conversion is initiated by CS falling. The conversion result is available at DOUT in unipolar serial format. A high bit, signaling the end of conversion (EOC), followed by the data bits (MSB first), make up the serial data stream ...
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... At this instant, the T/H switches the input side GND. The retained charge on C sample of the input, unbalancing the node ZERO at the comparator’s input. In hold mode, the capacitive DAC adjusts during the remainder of the conversion cycle to restore node ZERO Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs 8 SCLK ANALOG INPUT 7 ...
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... Higher-frequency signals cause aliasing prob- lems unless undersampling techniques are used. CS SHDN DOUT Figure 5. MAX187/MAX189 Shutdown Sequence Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs Input Protection The MAX187 can be used with an internal or external ref- + 0.3V erence, while the MAX189 requires an external reference. ...
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... CONVERSIONS PER SECOND Figure 6. Average Supply Current vs. Conversion Rate Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs The actual conversion does not require the external clock. This frees the FP from the burden of running the SAR conversion clock, and allows the conversion result to be read back at the FP’ ...
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... CYCLE TIME Figure 8. MAX187/MAX189 Interface Timing Sequence CS t CS0 SCLK t DV DOUT t APR (TRACK) INTERNAL T/H Figure 9. MAX187/MAX189 Detailed Serial-Interface Timing Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs B11 B10 EOC EOC CLOCK OUTPUT DATA TRACK 0µ 0.250µs = 3.25µs TOTAL = 12.25µ ...
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... INPUT VOLTAGE (LSBs) Figure 10. MAX187/MAX189 UnipolarTransfer Function, 4.096V = Full Scale Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs fundamental input frequency. ADCs have traditionally been evaluated by specifications such as Zero and Full- Scale Error, Integral Nonlinearity (INL), and Differential Nonlinearity (DNL). Such parameters are widely accepted ...
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... INPUT FREQUENCY (kHz) Figure 12. Effective Bits vs. Input Frequency Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs The MAX187/MAX189 serial interface is fully compatible with SPI, QSPI, and MICROWIRE standard serial inter- faces serial interface is available, set the CPU’s serial inter- face in master mode so the CPU generates the serial clock ...
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... MSB D10 DOUT EOC Figure 14. SPI/MICROWIRE Serial Interface Timing (CPOL = CPHA = 0) Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs Set CPOL = CPHA = 0. Unlike SPI, which requires two 1-byte reads to acquire the 12 bits of data from the ADC, CS QSPI allows the minimum number of clock cycles neces- SCLK sary to clock in the data ...
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... MAX187 0.1µ SHDN AIN REF SCLK ANALOG 5 6 GND DOUT INPUT 4.7µF SIGNAL GROUND Figure 16. 12-Bit Isolated ADC Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs MSB D10 6N136 8 7 3kI 6 5 6N136 8 7 3kI 6 470I 5 6N136 ...
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... Minimize capacitor lead lengths for best supply-noise rejection. If the +5V power supply is very noisy, a 10I resistor can be connected as a lowpass filter to attenuate supply noise (Figure 17). Maxim Integrated +5V, Low-Power, 12-Bit Serial ADCs power supply may DD Figure 17. Power-Supply Grounding Condition ...
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... MAX187BCWE+ 0NC to +70NC MAX187CCWE+ 0NC to +70NC MAX187AEPA+ -40NC to +85NC MAX187BEPA+ -40NC to +85NC MAX187CEPA+ -40NC to +85NC MAX187AEWE+ -40NC to +85NC MAX187BEWE+ -40NC to +85NC MAX187CEWE+ -40NC to +85NC 0NC to +70NC MAX189ACPA+ MAX189BCPA+ 0NC to +70NC MAX189CCPA+ 0NC to +70NC MAX189ACWE+ 0NC to +70NC MAX189BCWE+ 0NC to +70NC ...
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... Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 2012 Maxim Integrated Products, Inc. © +5V, Low-Power, 12-Bit Serial ADCs DESCRIPTION The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc. MAX187/MAX189 Revision History PAgES CHANgED — ...