604-00026 Parallax Inc, 604-00026 Datasheet
604-00026
Specifications of 604-00026
Related parts for 604-00026
604-00026 Summary of contents
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Rev 1; 3/99 General Description The MAX1270/MAX1271 are multirange, 12-bit data- acquisition systems (DAS) that require only a single +5V supply for operation, yet accept signals at their analog inputs that may span above the power-supply rail and below ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs ABSOLUTE MAXIMUM RATINGS V to AGND............................................................-0.3V to +6V DD AGND to DGND.....................................................-0.3V to +0.3V CH0–CH7 to AGND ......................................................... ±16.5V REF, REFADJ to AGND ..............................-0. SSTRB, DOUT to DGND.............................-0. SHDN, CS, ...
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ELECTRICAL CHARACTERISTICS (continued +5.0V ±5%; unipolar/bipolar range; external reference mode (50% duty cycle), 18 clock/conversion cycle, 110ksps; T PARAMETERS SYMBOL ANALOG INPUT ANALOG INPUT Track/Hold Acquisition Time t ACQ Small-Signal Bandwidth Input Voltage Range V Input ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs ELECTRICAL CHARACTERISTICS (continued +5.0V ±5%; unipolar/bipolar range; external reference mode (50% duty cycle), 18 clock/conversion cycle, 110ksps; T PARAMETERS SYMBOL Input Resistance REFADJ Threshold for Buffer Disable POWER REQUIREMENT POWER ...
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TIMING CHARACTERISTICS (V = +4.75V to +5.25; unipolar/bipolar range; external reference mode 2MHz unless otherwise noted. Typical values are T A MIN MAX PARAMETERS DIN to SCLK Setup DIN to SCLK Hold ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs (Typical Operating Circuit +5V; external reference mode 110ksps +25°C; unless otherwise noted.) A SUPPLY CURRENT vs. SUPPLY VOLTAGE ...
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Operating Circuit +5V; external reference mode 110ksps +25°C; unless otherwise noted.) A AVERAGE SUPPLY CURRENT vs. CONVERSION RATE (USING STANDBY 5V, INTERNAL REFERENCE 2MHz 7 CLK EXTERNAL ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs +5V 510k 100k REFADJ 0.01µF 24k Figure 1. Reference-Adjust Circuit Detailed Description Converter Operation The MAX1270/MAX1271 multirange, fault-tolerant ADCs use successive approximation and internal track/hold (T/H) circuitry to convert an analog signal to a ...
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The ADC’s input small-signal bandwidth depends on the selected input range and varies from 1.5MHz to 5MHz (see Electrical Characteristics). The MAX1270/ MAX1271 maximum sampling rate is 110ksps. By using undersampling techniques possible to digitize high-speed transient events ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs Table 1. Control-Byte Format Bit 7 Bit 6 Bit 5 (MSB) START SEL2 SEL1 BIT NAME First logic “1” after CS goes low defines the beginning of the control byte. 7 (MSB) START SEL2, ...
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Input data (control byte) is clocked in at DIN at the ris- ing edge of SCLK. CS enables communication with the MAX1270/MAX1271. After CS falls, the first arriving logic “1” bit represents the start bit (MSB) of the input control ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs CS t SDV SSTRB HIGH-Z SCLK • Figure 7. External Clock Mode SSTRB Detailed Timing CS SCLK 1 8 CONTROL BYTE Ø MSB LSB START SEL2 SEL1 SEL0 RNG BIP PD1 PD0 DIN 18 ...
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CS SCLK 1 DIN START SEL2 SEL1 SEL0 RNG MSB SSTRB HIGH-Z DOUT A/D STATE Figure 9. Internal Clock Mode, 20 SCLK/Conversion Timing • • • CSH • • • SSTRB • • • SCLK SCLK #8 Figure ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs CS SCLK 1 8 CONTROL BYTE Ø START SEL2 SEL1 SEL0 RNG BIP PD1 PD0 DIN 13 SCLK SSTRB HIGH-Z DOUT ACQUISITION CONVERSION A/D STATE Figure 11. Internal Clock Mode, 13 Clocks/Conversion Timing CS ...
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MAX1270 MAX1271 A = 1.638 V REFADJ 10k 2.5V Figure 13a. Internal Reference MAX1270 MAX1271 A = 1.638 V REFADJ 10k 2.5V Figure 13b. External Reference, Reference at REF MAX1270 MAX1271 A = 1.638 V REFADJ 10k 2.5V Figure 13c. ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs OUTPUT CODE FULL-SCALE 11... 111 TRANSITION 11... 110 11... 101 00... 011 00... 010 00... 001 00... 000 INPUT VOLTAGE (LSB) Figure 14a. Unipolar Transfer Function Transfer Function Output data ...
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DGND 2 N.C. 3 DGND 4 MAX1270 SCLK 5 MAX1271 CS 6 DIN 7 SSTRB 8 N.C. 9 DOUT 10 SHDN 11 AGND 12 DIP Ordering Information (continued) TEMP. PART PIN-PACKAGE RANGE 24 Narrow Plastic DIP MAX1270AENG ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs ________________________________________________________Package Information 7-186 ___________________________________________________________________________________ ...
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Multirange, +5V, 8-Channel, ____________________________________________________________________________________ Serial 12-Bit ADCs Package Information (continued) 7-187 ...
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Multirange, +5V, 8-Channel, Serial 12-Bit ADCs 7-188 ___________________________________________________________________________________ NOTES ...