EVAL-AD7940CBZ Analog Devices Inc, EVAL-AD7940CBZ Datasheet
EVAL-AD7940CBZ
Specifications of EVAL-AD7940CBZ
Related parts for EVAL-AD7940CBZ
EVAL-AD7940CBZ Summary of contents
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FEATURES Fast throughput rate: 100 kSPS Specified for Low power 4 mW typ at 100 kSPS with 3 V supplies 17 mW typ at 100 kSPS with 5 V supplies Wide input ...
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... Typical Connection Diagram ................................................... 12 Modes of Operation ....................................................................... 13 REVISION HISTORY 6/04—Revision 0: Initial Version Normal Mode.............................................................................. 13 Power-Down Mode.................................................................... 14 Power vs. Throughput Rate ........................................................... 15 Serial Interface ................................................................................ 16 Microprocessor Interfacing........................................................... 17 AD7940 to TMS320C541 .......................................................... 17 AD7940 to ADSP-218x.............................................................. 17 AD7940 to DSP563xx ................................................................ 18 Application Hints ........................................................................... 19 Grounding and Layout .............................................................. 19 Evaluating the AD7940 Performance ...................................... 19 Outline Dimensions ....................................................................... 20 Ordering Guide .......................................................................... 20 Rev Page ...
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SPECIFICATIONS 2.5 MHz SCLK Table 2. Parameter DYNAMIC PERFORMANCE 2 Signal-to-Noise + Distortion (SINAD) 2 Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) 2 Intermodulation Distortion ...
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AD7940 Parameter 4 Power Dissipation Normal Mode (Operational) Full Power-Down 1 Temperature range for B Version is –40°C to +85°C. 2 See the Terminology section. 3 Sample tested at initial release to ensure compliance. 4 See the Power vs. Throughput ...
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TIMING SPECIFICATIONS Sample tested at initial release to ensure compliance. All input signals are specified with (10 voltage level 5.5 V; ...
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AD7940 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 4. Parameter V to GND DD Analog Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND Input Current to Any Pin Except Supplies ...
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PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS SOT- AD7940 GND SDATA 2 5 TOP VIEW V SCLK (Not to Scale) Figure 3. SOT-23 Pin Configuration Table 5. Pin Function Descriptions Pin No. Pin No. ...
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AD7940 TERMINOLOGY Integral Nonlinearity This is the maximum deviation from a straight line passing through the endpoints of the ADC transfer function. The end- points of the transfer function are zero scale, a point 1/2 LSB below the first code ...
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TYPICAL PERFORMANCE CHARACTERISTICS Figure 5 shows a typical FFT plot for the AD7940 at 100 kSPS sample rate and 10 kHz input frequency. Figure 6 shows the signal-to-(noise + distortion) ratio performance versus the input frequency for various supply voltages ...
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AD7940 1 3.00V DD ° TEMP = 25 C 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 0 2000 4000 6000 8000 10000 12000 14000 16000 CODE Figure 9. AD7940 Typical INL 0 3.00V DD ° ...
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CIRCUIT INFORMATION The AD7940 is a fast, low power, 14-bit, single-supply ADC. The part can be operated from a 2. 5.5 V supply. When operated at either supply, the AD7940 is capable of ...
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AD7940 ADC TRANSFER FUNCTION The output coding of the AD7940 is straight binary. The de- signed code transitions occur at successive integer LSB values, i.e., 1 LSB, 2 LSBs. The LSB size is V /16384. The ideal transfer DD characteristic ...
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MODES OF OPERATION The mode of operation of the AD7940 is selected by controlling the (logic) state of the CS signal during a conversion. There are two possible modes of operation, normal and power-down. The point at which CS is ...
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AD7940 POWER-DOWN MODE This mode is intended for use in applications where slower throughput rates are required. Either the ADC is powered down between each conversion series of conversions may be performed at a high throughput rate, and ...
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POWER VS. THROUGHPUT RATE By using the power-down mode on the AD7940 when not converting, the average power consumption of the ADC decreases at lower throughput rates. Figure 19 shows how as the throughput rate is reduced, the part remains ...
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AD7940 SERIAL INTERFACE Figure 20 shows the detailed timing diagram for serial interfac- ing to the AD7940. The serial clock provides the conversion clock and also controls the transfer of information from the AD7940 during conversion. The CS signal initiates ...
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MICROPROCESSOR INTERFACING The serial interface on the AD7940 allows the part to be directly connected to a range of many different microprocessors. This section explains how to interface the AD7940 with some of the more common microcontroller and DSP serial ...
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AD7940 For example, if the ADSP-2189 had a 20 MHz crystal, such that it had a master clock frequency of 40 MHz, the master cycle time would be 25 ns. If the SCLKDIV register is loaded with the value 7, ...
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... PC via the evaluation board controller. The evaluation board con- troller can be used in conjunction with the AD7940 evaluation board, as well as many other Analog Devices evaluation boards ending in the CB designator, to demonstrate/evaluate the ac and dc performance of the AD7940. ...
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... This can be used as a standalone evaluation board or in conjunction with the Evaluation Controller Board for evaluation/demonstration purposes. 3 This board is a complete unit allowing control and communicate with all Analog Devices evaluation boards ending in the CB designators. To order a complete evaluation kit, the particular ADC evaluation board needs to be ordered, e.g., EVAL-AD7940CB, the EVAL-CONTROL BRD2, and transformer. See the Evaluation Board application note for more information. © ...