MAX1245ACAP Maxim Integrated, MAX1245ACAP Datasheet
MAX1245ACAP
Specifications of MAX1245ACAP
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MAX1245ACAP Summary of contents
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... Low Power: 0.8mA (100ksps) o Internal Track/Hold, 100kHz Sampling Rate o SPI/QSPI/MICROWIRE/TMS320-Compatible 4-Wire Serial Interface o Software-Configurable Unipolar or Bipolar Inputs o 20-Pin DIP/SSOP Packages ________________Ordering Information PART* MAX1245ACPP MAX1245BCPP MAX1245ACAP MAX1245BCAP MAX1245AEPP MAX1245BEPP MAX1245AEAP MAX1245BEAP * Contact factory for availability of alternate surface-mount packages. ___________________Pin Configuration TOP VIEW V DD 0.1µ ...
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Low-Power, 8-Channel, Serial 12-Bit ADC ABSOLUTE MAXIMUM RATINGS V to AGND, DGND .............................................. -0.3V to +6V DD AGND to DGND.................................................... -0.3V to +0.3V CH0–CH7, COM to AGND, DGND ............ -0. VREF to AGND........................................... -0. Digital ...
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ELECTRICAL CHARACTERISTICS (continued +2.375V to +3.3V 0V, f COM DD VREF = 2.048V applied to VREF pin PARAMETER SYMBOL ANALOG/COM INPUTS Input Voltage Range, Single- Ended and Differential (Note 6) Multiplexer Leakage Current Input ...
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Low-Power, 8-Channel, Serial 12-Bit ADC TIMING CHARACTERISTICS (V = +2.375V to +3.3V 0V, T COM DD PARAMETER SYMBOL Acquisition Time t DIN to SCLK Setup DIN to SCLK Hold SCLK Fall to Output Data Valid CS Fall ...
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Operating Characteristics (continued 2.5V, VREF = 2.048V 1.5MHz CLK INTEGRAL NONLINEARITY vs. TEMPERATURE 0. 2.375V 0.45 DD 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0 -55 - ...
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Low-Power, 8-Channel, Serial 12-Bit ADC ____________________________Typical Operating Characteristics (continued 2.5V, VREF = 2.048V 1.5MHz CLK AVERAGE SUPPLY CURRENT vs. CONVERSION RATE 1000 REF = 2.5V DD CODE = 101010100000 = ...
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Description PIN NAME 1–8 CH0–CH7 Sampling Analog Inputs Ground reference for analog inputs. Sets zero-code voltage in single-ended mode. Must be stable to 9 COM ±0.5LSB. Three-Level Shutdown Input. Pulling SHDN low shuts the MAX1245 down to 10µA (max) ...
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Low-Power, 8-Channel, Serial 12-Bit ADC _______________Detailed Description The MAX1245 analog-to-digital converter (ADC) uses a successive-approximation conversion technique and input track/hold (T/H) circuitry to convert an analog sig- nal to a 12-bit digital output. A flexible serial interface provides easy ...
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R = 12kΩ the source impedance of the IN S input signal, and t is never less than 2.0µs. Note ACQ that source impedances below 1kΩ do not significantly affect the AC performance of the ADC. Higher ...
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Low-Power, 8-Channel, Serial 12-Bit ADC Table 1. Control-Byte Format BIT 7 BIT 6 BIT 5 (MSB) START SEL2 SEL1 BIT NAME DESCRIPTION The first logic “1” bit after CS goes low defines the beginning of the control byte. 7(MSB) ...
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ADC, and two more 8-bit transfers to clock out the 12-bit conversion result). See Figure 17 for MAX1245 QSPI connections. Simple Software Interface Make sure the CPU’s serial interface runs in ...
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Low-Power, 8-Channel, Serial 12-Bit ADC CS t CSS t CSH SCLK DIN t DV DOUT Figure 7. Detailed Serial-Interface Timing CS t SDV SSTRB SCLK Figure 8. External-Clock-Mode SSTRB Detailed Timing In internal clock mode, ...
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CS SCLK SEL2 SEL1 SEL0 UNI/ DIN BIP START SSTRB DOUT A/D STATE IDLE Figure 9. Internal Clock Mode Timing CS • • • t CSH SSTRB • • • SCLK • • • PD0 ...
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Low-Power, 8-Channel, Serial 12-Bit ADC The fastest the MAX1245 can run is 15 clocks per conver- sion with CS held low between conversions. Figure 11a shows the serial-interface timing necessary to perform a conversion every 15 SCLK cycles in ...
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CLOCK MODE SHDN SETS EXTERNAL CLOCK MODE DIN DOUT 12 DATA BITS MODE POWERED UP Figure 12a. Timing Diagram Power-Down Modes, External Clock CLOCK MODE SETS INTERNAL CLOCK MODE DIN S X ...
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Low-Power, 8-Channel, Serial 12-Bit ADC Table 6. Full Scale and Zero Scale UNIPOLAR MODE Full Scale VREF + COM also specify the clock mode. When software shutdown is asserted, the ADC continues to operate in the last speci- fied ...
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OUTPUT CODE FULL-SCALE TRANSITION 111 110 101 011 010 001 000 0 ...
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Low-Power, 8-Channel, Serial 12-Bit ADC 1 CH0 2 CH1 CH2 3 4 ANALOG CH3 MAX1245 INPUTS 5 CH4 6 CH5 7 CH6 8 CH7 9 COM 10 SHDN Figure 17. MAX1245 QSPI Connections High-Speed Digital Interfacing with QSPI The ...
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TMS320LC3x-to-MAX1245 Interface Figure 18 shows an application circuit to interface the MAX1245 to the TMS320 in external clock mode. The tim- ing diagram for this interface circuit is shown in Figure 19. Use the following steps to initiate a conversion ...
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Low-Power, 8-Channel, Serial 12-Bit ADC Chip Information TRANSISTOR COUNT: 2554 20 ______________________________________________________________________________________ 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 RoHS ...
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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 ____________________ 21 © 2009 Maxim Integrated Products +2 ...