AD7992 Analog Devices, AD7992 Datasheet
AD7992
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AD7992 Summary of contents
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... CONVST pin command mode where conversions occur across I operations automatic conversion interval mode selected through software control. The AD7992 requires an external reference in the range of 1 This allows the widest dynamic input range to the ADC. DD ...
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... Writing Two Bytes of Data to a Limit Register or Hysteresis Register ........................................................................................ 22 Reading Data from the AD7992................................................... 23 ALERT/BUSY Pin .......................................................................... 24 SMBus ALERT............................................................................ 24 Placing the AD7992-1 into High Speed Mode....................... 24 The Address Select (AS) Pin ..................................................... 24 Modes of Operation ....................................................................... 25 Mode 1—Using the CONVST Pin ........................................... 25 Mode 2 – Command mode....................................................... 26 Mode 3—Automatic Cycle Mode............................................. 27 Outline Dimensions ...
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... LOGIC INPUTS (SDA, SCL) Input High Voltage, V INH Input Low Voltage, V INL Input Leakage Current Input Capacitance Input Hysteresis, V HYST 400 kHz; for the AD7992-1 all specifications apply for f B Version Unit 70.5 dB min 71 dB min –78 dB max 2 –79 dB max –90 dB typ – ...
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... AD7992 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 Output Coding CONVERSION RATE Conversion Time Throughput Rate ...
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... Guaranteed by initial characterization. All values measured with the input filtering enabled. C line. t and t measured between 0 High speed mode timing specifications apply to the AD7992-1 only. Standard and fast mode timing specifications apply to both the AD7992-0 and the AD7992-1. See Figure 2. Unless otherwise noted, V Table 3. Parameter Conditions f Standard mode ...
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... AD7992 Parameter Conditions t Standard mode 10 Fast mode High speed mode C = 100 pF max 400 pF max B t Standard mode 11 Fast mode High speed mode C = 100 pF max 400 pF max B t Standard mode 11A Fast mode High speed mode C = 100 pF max 400 pF max ...
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... device reliability. −0 0 ±10 mA −40°C to +125°C −65°C to +150° 150°C 200°C/W (MSOP) 44°C/W (MSOP) 240 (+0/−5)°C 260 (+0)°C 1.5 kV Rev Page AD7992 ...
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... AS Pin AD7992-0 GND AD7992-0 V AD7992-1 GND AD7992 AD7992-x Float 1 If the AS pin is left floating on any of the AD7992 parts, the device address is 010 0000. This gives each AD7992 device three different address options. CONVST SCL 1 10 AGND SDA AD7992 ALERT 3 ...
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... The AD7992 is tested using the CCIF standard where two input frequencies near the top end of the input bandwidth are used. In this case, the second-order terms are usually distanced in frequency from the original sine waves while the third-order terms are usually at a frequency close to the input frequencies ...
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... AD7992 TYPICAL PERFORMANCE CHARACTERISTICS 0 –20 –40 –60 –80 –100 –120 FREQUENCY (kHz) Figure 4. Dynamic Performance with 5 V Supply and 2.5 V Reference, 121 kSPS, Mode 1, Single-Channel Mode 0 –20 –40 –60 –80 –100 –120 FREQUENCY (kHz) Figure 5. Dynamic Performance with 5.5 V Supply and 5.5 V Reference, ...
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... POSITIVE DNL 0 NEGATIVE DNL 1.2 1.7 2.2 2.7 3.2 3.7 4.2 REFERENCE VOLTAGE ( Mode 1, 121 kSPS DD –40°C +25°C +85°C 0 2.7 3.2 3.7 4.2 4.7 SUPPLY VOLTAGE (V) MODE 2 VDD = 5V MODE 2 VDD = 3V 100 600 1100 1600 2100 2600 SCL FREQUENCY (kHz Bus Rate for V AD7992 4.7 5.2 MODE 1 VDD = 5V MODE 1 VDD = 3V 3100 = 3 V and ...
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... AD7992 12.0 11.8 ENOB 11.6 11.4 11.2 SINAD 11.0 10.8 10.6 10.4 1.200 2.048 2.500 2.700 3.000 3.300 4.096 4.500 5.000 REFERENCE VOLTAGE (V) Figure 16. ENOB/SINAD vs. Reference Voltage, Mode 1, 121 kSPS 74 ENOB SINAD Rev Page ...
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... ADC Transfer Function The output coding of the AD7992 is straight binary. The 2 C interface designed code transitions occur at successive integer LSB values (i.e., 1 LSB, 2 LSB, and so on). The LSB size for the AD7992 is REF /4096. Figure 19 shows the ideal transfer characteristic for IN the AD7992. ...
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... Therefore, if operating the AD7992 in either standard or fast mode five AD7992 devices can be connected to the bus (3 × AD7992-0 and 2 × AD7992 × AD7992-1 and 2 × AD7992-0). In high speed mode three AD7992-1 devices can be connected to the bus. Wake up from power-down prior to a conversion is approx- imately 1 µ ...
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... INPUT FREQUENCY (kHz) Figure 22. THD vs. Analog Input Frequency for Various Supply Voltages, F –40 –50 –60 –70 –80 –90 R SOURCE –100 1 INPUT FREQUENCY (kHz) Figure 23. THD vs. Analog Input Frequency for Various Source Impedances for V Rev Page AD7992 V = 2.5V REF ...
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... LSBs are used as pointer bits to store an address that points to one of the AD7992’s data registers. The 4 MSBs are used as command bits when operating in Mode 2 (see the Modes of Operation section). The first byte following each write address is the ...
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... CONFIGURATION REGISTER The configuration register is a 8-bit, read/write register that is used to set the operating modes of the AD7992. The MSB of the register is unused and is a don’t care bit. The bit functions of the configuration register are outlined in Table 9. A single-byte write is necessary when writing to the configuration register ...
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... ADC in straight binary format. A 2-byte read is needed to read data from this register. Table 12 shows the contents of the first byte to be read from the AD7992, and Table 13 shows the contents of the second byte. Table 12. Conversion Value Register (First Read) D15 ...
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... The cycle timer register is an 8-bit read/write register that stores the conversion interval value for the automatic cycle mode of registers the AD7992 (see the Modes of Operation section). The 5 MSBs LOW of the cycle timer register are unused and should contain 0s at all times (see the Sample Delay and Bit Trial Delay section). On power-up, the cycle timer register contains all 0s, thus disabling automatic cycle operation of the AD7992 ...
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... Like all I C-compatible devices, the AD7992 has a 7-bit serial address. The 3 MSBs of this address for the AD7992 are set to 010. The device comes in two versions, the AD7992-0 and the AD7992-1. The two versions have three different I available, which are selected by either tying the address select ...
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... WRITING TO THE AD7992 Depending on the register being written to, there are three different writes for the AD7992. WRITING TO THE ADDRESS POINTER REGISTER FOR A SUBSEQUENT READ In order to read from a particular register, the address pointer register must first contain the address of that register does ...
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... MOST SIGNIFICANT DATA BYTE If the master is write-addressing the AD7992, it can write to more than one register with out re-addressing the ADC. After the first write operation has completed for the first data register, during the next byte, the master writes to the address pointer byte to select the next data register for a write operation ...
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... When reading data back from a register, such as the conversion result register, if more than two read bytes are supplied, the same or new data is read from the AD7992 without the need to re-address the device. This allows the master to continuously read from a data register without having to re-address the AD7992 ...
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... STOP condition. When the STOP condition is issued, the devices all return to fast mode. THE ADDRESS SELECT (AS) PIN The address select pin on the AD7992 is used to set the I address for the AD7992 device. The AS pin can be tied AGND, or left floating. The selection should be made as close as possible to the AS pin ...
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... CONVST still initiates a conversion, but the result is invalid because the AD7992 is not fully powered up when the conversion takes place. To maintain the performance of the AD7992 in this mode recommended that the I is quiet when a conversion is taking place. The cycle timer register and Command Bits the address pointer register should contain all 0s when operating the AD7992 in this Mode 1 ...
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... Command Bit, C1, has been clocked in midway through the write to the address pointer register. Following this, the AD7992 must be addressed again to tell it that a read operation is required. The read then takes place from the conversion result register. This read accesses the result from the conversion selected via the command bits ...
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... An automatic conversion cycle can be selected and enabled by writing a value to the cycle timer register. A conversion cycle interval can be set up on the AD7992 by programming the relevant bits in the 8-bit cycle timer register, as decoded in Table 23. Only the 3 LSBs are used; the 5 MSBs should contain 0s (see the Sample Delay and Bit Trial Delay section) ...
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... AD7992BRMZ-1REEL –40°C to +125°C EVAL-AD7992CB 1 2 The AD7992-0 supports standard and fast I C interface modes. The AD7992-1 supports standard, fast, and high speed I 2 Linearity error here refers to integral nonlinearity Pb-free part. Purchase of licensed components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser under the Philips I ...