EVAL-AD7946CBZ Analog Devices Inc, EVAL-AD7946CBZ Datasheet
EVAL-AD7946CBZ
Specifications of EVAL-AD7946CBZ
Related parts for EVAL-AD7946CBZ
EVAL-AD7946CBZ Summary of contents
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FEATURES 14-bit resolution with no missing codes Throughput: 500 kSPS INL: ±0.4 LSB typical, ±1 LSB maximum (±0.0061% of FSR) SINAD kHz THD: −100 kHz Pseudo differential analog input range ...
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... CS MODE 3-Wire, No BUSY Indicator .................................. 17 CS Mode 3-Wire with BUSY Indicator ................................... 18 CS Mode 4-Wire, No BUSY Indicator..................................... 19 CS Mode 4-Wire with BUSY Indicator ................................... 20 Chain Mode, No BUSY Indicator ............................................ 21 Chain Mode with BUSY Indicator........................................... 22 Application Guidelines .................................................................. 23 Layout .......................................................................................... 23 Evaluating the AD7946’s Performance.................................... 23 Outline Dimensions ....................................................................... 24 Ordering Guide .......................................................................... 24 Rev Page ...
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SPECIFICATIONS VDD = 4 5.5 V, VIO = 2 VDD, REF = VDD, T Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Absolute Input Voltage Analog Input CMRR Leakage Current at 25°C Input Impedance ACCURACY No ...
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AD7946 VDD = 4 5.5 V, VIO = 2 VDD, REF = VDD, T Table 3. Parameter Conditions REFERENCE Voltage Range Load Current 500 kSPS, REF = 5 V SAMPLING DYNAMICS −3 dB Input Bandwidth Aperture ...
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TIMING SPECIFICATIONS T = −40°C to +85°C, VDD = 4 5.5 V, VIO = 2 5 VDD + 0.3 V, whichever is the lowest, unless otherwise stated. A See Figure 2 and Figure 3 ...
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AD7946 ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Rating Analog Inputs IN IN− 1 GND − 0 VDD + 0 ±130 mA REF GND − 0 VDD + 0.3 V Supply Voltages VDD, ...
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PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS REF 1 10 VDD 2 9 AD7946 IN TOP VIEW (Not to Scale) IN– GND 5 6 Figure 4. 10-Lead MSOP Pin Configuration Table 6. Pin Function Descriptions 1 Pin No. ...
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AD7946 TYPICAL PERFORMANCE CHARACTERISTICS 1.0 POSITIVE INL = +0.17LSB 0.8 NEGATIVE INL = –0.26LSB 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 4096 8192 CODE Figure 6. Integral Nonlinearity vs. Code 300000 261120 250000 200000 150000 100000 50000 ...
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REFERENCE VOLTAGE (V) Figure 12. SNR, SINAD, and ENOB vs. Reference Voltage 90.0 87.5 85.0 82.5 80.0 –55 –35 – TEMPERATURE (°C) Figure 13. ...
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AD7946 1000 750 VDD 500 250 VIO 0 4.50 4.75 5.00 SUPPLY (V) Figure 18. Operating Current vs. Supply 1000 750 500 250 0 –55 –35 – TEMPERATURE (°C) Figure 19. Power-Down Current vs. Temperature 1000 750 ...
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TERMINOLOGY Integral Nonlinearity Error (INL) INL refers to the deviation of each individual code from a line drawn from negative full scale through positive full scale. The point used as negative full scale occurs ½ LSB before the first code ...
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AD7946 THEORY OF OPERATION IN+ REF GND IN– CIRCUIT INFORMATION The AD7946 is a fast, low power, single-supply, precise 14-bit ADC using a successive approximation architecture. The AD7946 can convert 500,000 samples per second (500 kSPS) and powers down between ...
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TYPICAL CONNECTION DIAGRAM Figure 25 shows an example of the recommended connection diagram for the AD7946 when multiple supplies are available REF (ADA4841 V– OR NOTE 3) NOTES 1. SEE REFERENCE SECTION FOR REFERENCE SELECTION. 2. ...
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AD7946 tolerated. The THD degrades as a function of the source impedance and the maximum input frequency, as shown in Figure 28. –80 –85 – 250Ω S –95 R =100Ω S –100 R = 50Ω ...
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POWER SUPPLY The AD7946 is specified uses two power supply pins: a core supply VDD and a digital input/output interface supply VIO. VIO allows direct interface with any logic between 1.8 V and ...
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AD7946 >5.2V ADR364 100nF 10µF 100nF ADA4841 0V TO 4.096V 33Ω 2.7nF Figure 32. Example of a Single-Supply Application Circuit DIGITAL INTERFACE Although the AD7946 has a reduced number of pins, it offers flexibility in its serial interface modes. The ...
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CS MODE 3-WIRE, NO BUSY INDICATOR This mode is usually used when a single AD7946 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 33 and the corresponding timing is given in Figure 34. With ...
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AD7946 CS MODE 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7946 is connected to an SPI-compatible digital host having an interrupt input. The connection diagram is shown in Figure 35, and the corresponding timing is ...
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CS MODE 4-WIRE, NO BUSY INDICATOR This mode is usually used when multiple AD7946s are connected to an SPI-compatible digital host. A connection diagram example using two AD7946s is shown in Figure 37, and the corresponding timing is given in ...
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AD7946 CS MODE 4-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7946 is connected to an SPI-compatible digital host, which has an interrupt input, and it is desired to keep CNV, which is used to sample ...
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CHAIN MODE, NO BUSY INDICATOR This mode can be used to daisy-chain multiple AD7946s on a 3-wire serial interface. This feature is useful for reducing component count and wiring connections, for example, in isolated multiconverter applications or for systems with ...
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AD7946 CHAIN MODE WITH BUSY INDICATOR This mode can be used to daisy-chain multiple AD7946s on a 3-wire serial interface while providing a BUSY indicator. This feature is useful for reducing component count and wiring connections, for example, in isolated ...
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... Figure 45 and Figure 46. EVALUATING THE AD7946’S PERFORMANCE Other recommended layouts for the AD7946 are outlined in the documentation of the evaluation board for the AD7946 (EVAL-AD7946CB). The evaluation board package includes a fully assembled and tested evaluation board, documentation, and software for controlling the board from a PC via the EVAL-CONTROL BRD3 ...
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... AD7946BCPZRL7 −40°C to +85°C 1 AD7946BCPZRL −40°C to +85° EVAL-AD7946CBZ EVAL-CONTROL BRD3Z RoHS Compliant Part. 2 This board can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRD3Z for evaluation/demonstration purposes. 3 This board allows control and communicate with all Analog Devices, Inc. evaluation boards ending in the CB designator. ...