AD7998BRU-0REEL Analog Devices Inc, AD7998BRU-0REEL Datasheet
AD7998BRU-0REEL
Specifications of AD7998BRU-0REEL
Related parts for AD7998BRU-0REEL
AD7998BRU-0REEL Summary of contents
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FEATURES 10- and 12-bit ADC with fast conversion time: 2 µs typ 8 single-ended analog input channels Specified for Low power consumption Fast throughput rate 188 kSPS Sequencer operation Automatic ...
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AD7997/AD7998 TABLE OF CONTENTS AD7997 Specifications..................................................................... 3 AD7998 Specifications..................................................................... Timing Specifications ................................................................ 7 Absolute Maximum Ratings............................................................ 9 ESD Caution.................................................................................. 9 Pin Configuration and Pin Function Descriptions.................... 10 Terminology .................................................................................... 11 Typical Performance Characteristics ........................................... 12 Circuit ...
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AD7997 SPECIFICATIONS Temperature range for B version is −40°C to +85°C. Unless otherwise noted, V specifications apply for 400 kHz; for the AD7997-1, all specifications apply for f SCL MIN ...
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AD7997/AD7998 Parameter LOGIC INPUTS (CONVST) Input High Voltage, V INH Input Low Voltage, V INL Input Leakage Current Input Capacitance LOGIC OUTPUTS (OPEN-DRAIN) Output Low Voltage Floating-State Leakage Current 3 Floating-State Output Capacitance ...
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AD7998 SPECIFICATIONS Temperature range for B version is −40°C to +85°C. Unless otherwise noted, V specifications apply for 400 kHz; for the AD7998-1, all specifications apply for f SCL MIN ...
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AD7997/AD7998 Parameter LOGIC INPUTS (CONVST) Input High Voltage, V INH Input Low Voltage, V INL Input Leakage Current Input Capacitance LOGIC OUTPUTS (OPEN-DRAIN) Output Low Voltage Floating-State Leakage Current 3 Floating-State Output Capacitance ...
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I C TIMING SPECIFICATIONS Guaranteed by initial characterization. All values measured with input filtering enabled measured between 0.3 VDD and 0.7 VDD. f High speed mode timing specifications apply to the AD7997-1/AD7998-1 only. Standard and fast mode ...
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AD7997/AD7998 Parameter Conditions Min t Standard mode 10 Fast mode 20 + 0.1 C High speed mode C = 100 pF max 400 pF max Standard mode 11 Fast mode 20 + 0.1 ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 4. Parameter V to GND DD Analog Input Voltage to GND Reference Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND Input Current to ...
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AD7997/AD7998 PIN CONFIGURATION AND PIN FUNCTION DESCRIPTIONS Table 5. Pin Function Descriptions Pin No. Mnemonic Function 1, 3, AGND Analog Ground. Ground reference point for all circuitry on the AD7997/AD7998. All analog input signals should referred to ...
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TERMINOLOGY Signal-to-Noise and Distortion Ratio (SINAD) The measured ratio of signal-to-noise and distortion at the out- put of the A/D converter. The signal is the rms amplitude of the fundamental. Noise is the sum of all nonfundamental signals up to ...
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AD7997/AD7998 TYPICAL PERFORMANCE CHARACTERISTICS 0 –20 –40 –60 –80 –100 –120 FREQUENCY (kHz) Figure 4. AD7998 Dynamic Performance with 5 V Supply and 2.5 V Reference, 121 kSPS, Mode 1 –10 –30 –50 –70 –90 –110 0 ...
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CODE Figure 10. Typical INL 2.7 V, Mode 1, 3.4 MHz f DD 1.0 0.8 0.6 0.4 0.2 0 –0.2 ...
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AD7997/AD7998 2.0 TEMPERATURE = +85°C 1.8 TEMPERATURE = +25°C TEMPERATURE = –40°C 1.6 TEMPERATURE = +85°C TEMPERATURE = +25°C MODE 2 - 147kSPS 1.4 TEMPERATURE = –40°C 1.2 1.0 MODE 1 - 121kSPS 0.8 0.6 0.4 0.2 0 2.7 3.2 ...
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CIRCUIT INFORMATION The AD7997/AD7998 are low power, 10- and 12-bit, single- supply, 8-channel A/D converters. The parts can be operated from a 2 5.5 V supply. The AD7997/AD7998 have an 8-channel multiplexer, an on- chip track-and-hold, an A/D ...
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AD7997/AD7998 TYPICAL CONNECTION DIAGRAM The typical connection diagram for the AD7997/AD7998 is shown in Figure 22. In this figure, the address select pin (AS) is tied however, AS can also be tied to AGND or left DD ...
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For ac applications, removing high frequency components from the analog input signal is recommended, by using an RC band- pass filter on the relevant analog input pin. In applications where harmonic distortion and signal-to-noise ratio are critical, the analog input ...
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AD7997/AD7998 INTERNAL REGISTER STRUCTURE The AD7997/AD7998 contain 17 internal registers that are used to store conversion results, high and low conversion limits, and information to configure and control the device (see Figure 25). Sixteen are data registers and one is ...
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CONFIGURATION REGISTER The configuration register is a 16-bit read/write register that is used to set the operating mode of the AD7997/AD7998. The 4 MSBs of the register are unused. The bit functions of all 12 LSBs of the configuration register ...
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AD7997/AD7998 CONVERSION RESULT REGISTER The conversion result register is a 16-bit, read-only register that stores the conversion result from the ADC in straight binary format. A 2-byte read is necessary to read data from this register. Table 13 shows the ...
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Hysteresis Register (CH1/CH2/CH3/CH4) Each hysteresis register is a 16-bit read/write register, of which only the 12 LSBs are used. The hysteresis register stores the hysteresis value, N, when using the limit registers. Each pair of limit registers has a dedicated ...
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AD7997/AD7998 CYCLE TIMER REGISTER The cycle timer register is an 8-bit, read/write register that stores the conversion interval value for the automatic cycle interval mode of the AD7997/AD7998 (see the Modes of Operation section the cycle ...
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SERIAL INTERFACE Control of the AD7997/AD7998 is carried out via the I compatible serial bus. The devices are connected to this bus as slave devices under the control of a master device, such as the processor. SERIAL BUS ADDRESS 2 ...
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AD7997/AD7998 WRITING TO THE AD7997/AD7998 Depending on the register being written to, there are three different writes for the AD7997/AD7998. WRITING TO THE ADDRESS POINTER REGISTER FOR A SUBSEQUENT READ In order to read from a particular register, the address ...
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SCL SDA START BY MASTER SERIAL BUS ADDRESS BYTE 9 1 SCL (CONTINUED) SDA (CONTINUED MOST SIGNIFICANT DATA BYTE R/W ACK. BY AD7997/AD7998 FRAME ...
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AD7997/AD7998 READING DATA FROM THE AD7997/AD7998 Reading data from the AD7997/AD7998 2-byte operation. Reading back the contents of the alert status register or the cycle timer register is a single-byte read operation, as shown in Figure ...
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ALERT/BUSY PIN The ALERT/BUSY pin may be configured as an alert output busy output, as shown in Table 12. SMBus ALERT The AD7997/AD7998 ALERT output is an SMBus interrupt line for devices that want to trade their ...
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AD7997/AD7998 MODES OF OPERATION When supplies are first applied to the AD7997/AD7998, the ADC powers up in sleep mode and normally remains in this shutdown state while not converting. There are three methods of initiating a conversion on the AD7997/AD7998. ...
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MODE 2 – COMMAND MODE This mode allows a conversion to be automatically initiated any time a write operation occurs. In order to use this mode, the Command Bits the address pointer byte shown in Table ...
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AD7997/AD7998 1 SCL SDA 7-BIT ADDRESS S 1 SCL SDA Sr 7-BIT ADDRESS SCL SDA 7-BIT ADDRESS ACK BY AD7997/AD7998 SCL SDA Sr 7-BIT ADDRESS R A ACK BY AD7997/AD7998 ...
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... AD7997BRU-1REEL –40°C to +85°C 3 AD7997BRUZ-1 –40°C to +85°C 3 AD7997BRUZ-1REEL –40°C to +85°C AD7998BRU-0 –40°C to +85°C AD7998BRU-0REEL –40°C to +85°C 3 AD7998BRUZ-0 –40°C to +85°C 3 AD7998BRUZ-0REEL –40°C to +85°C AD7998BRU-1 –40°C to +85°C AD7998BRU-1REEL – ...
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AD7997/AD7998 NOTES 2 Purchase of licensed I C components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser under the Philips I 2 Rights to use these components system, ...