AD7829-1 Analog Devices, AD7829-1 Datasheet
AD7829-1
Specifications of AD7829-1
Related parts for AD7829-1
AD7829-1 Summary of contents
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... IN6 V IN7 V IN8 V MID The AD7829-1 is available in a 28-lead, wide body, small outline IC (SOIC_W) and a 28-lead thin shrink small outline package (TSSOP). PRODUCT HIGHLIGHTS 1. Fast Conversion Time. The AD7829-1 has a conversion time of 420 ns. Faster conversion times maximize the DSP processing time in a real-time system. ...
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... Circuit Description..................................................................... 10 REVISION HISTORY 7/06—Revision 0: Initial Version Typical Connection Diagram ................................................... 10 ADC Transfer Function............................................................. 11 Analog Input ............................................................................... 11 Power-Up Times......................................................................... 14 Power vs. Throughput................................................................ 14 Operating Modes........................................................................ 15 Parallel Interface......................................................................... 17 Microprocessor Interfacing........................................................... 18 AD7829-1 to 8051 ...................................................................... 18 AD7829-1 to PIC16C6x/PIC16C7x......................................... 18 AD7829-1 to ADSP-21xx .......................................................... 18 Interfacing Multiplexer Address Inputs .................................. 18 Outline Dimensions ....................................................................... 20 Ordering Guide .......................................................................... 20 Rev Page ...
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... V min 0.8 V max 2 V min 0.4 V max ±1 μA max 10 pF max Rev Page AD7829-1 Test Conditions/Comments kHz MHz IN SAMPLE fa = 27.3 kHz 28.3 kHz kHz IN See Analog Input section Input voltage span = 2.5 V Default V = 1.25 V MID Input voltage span = 2 V ...
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... AD7829-1 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage High Impedance Leakage Current High Impedance Capacitance CONVERSION RATE Track/Hold Acquisition Time Conversion Time POWER SUPPLY REJECTION V ± 10% DD POWER REQUIREMENTS Normal Operation Power-Down Power Dissipation ...
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... OUTPUT PIN C L 50pF 200µ Figure 2. Load Circuit for Access Time and Bus Relinquish Time Rev Page ± 10%, and the time required for an DD 2.1V AD7829-1 ...
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... AD7829-1 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to AGND DGND DD Analog Input Voltage to AGND IN1 IN8 Reference Input Voltage to AGND V Input Voltage to AGND MID Digital Input Voltage to DGND Digital Output Voltage to DGND Operating Temperature Range ...
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... Table 4. Pin Function Descriptions Pin No. Mnemonic Description Analog Input Channels. The AD7829-1 has eight analog input channels. The inputs have an input span of 2.5 V IN8 IN1 and 2 V, depending on the supply voltage (V using the V MID ( ± 10%). See the Analog Input section of the data sheet for more information. ...
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... The figure given is the worst case across all eight channels of the AD7829-1. Relative Accuracy or Endpoint Nonlinearity The maximum deviation from a straight line passing through the endpoints of the ADC transfer function ...
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... PSR (Power Supply Rejection) Variations in power supply affect the full-scale transition but not the converter’s linearity. Power supply rejection is the maximum change in the full-scale transition point due to a input of the AD7829-1. change in power supply voltage from the nominal value. Rev Page AD7829-1 ...
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... D0 voltage source that can vary from 4 5.5 V (see Table 5 in the Analog Input section). When V AD7829-1 powers low current mode, that is, power-down. Ensure that the CONVST line is not floating when V because this can put the AD7829-1 into an unknown state. Rev Page ...
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... LSB values (that is, 1 LSB, 2 LSBs, and so on). The LSB size is equal to V /256 ( V), or the LSB size is equal to (0.8 V REF V). The ideal transfer characteristic for the AD7829 shown in Figure 5V) DD 11111111 ...
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... V ± 2%. Analog Input Structure Figure 13 shows an equivalent circuit of the analog input structure of the AD7829-1. The two diodes, D1 and D2, provide ESD protection for the analog inputs. Care must be taken to ensure that the analog input signal never exceeds the supply rails by more than 200 mV. This causes these diodes to become AD7829-1 forward biased and start conducting current into the substrate ...
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... When returning IN1 selected is the IN Figure 15. Effective Number of Bits vs. Acquisition Time for the AD7829-1 The on-chip track-and-hold can accommodate input frequencies to 10 MHz, making the AD7829-1 ideal for subsampling applications. When the AD7829-1 is converting a 10 MHz input signal at a sampling rate of 2 MSPS, the effective ...
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... The power dissipation during normal operation is 36 mW, V time is 330 ns (@ +25°C), the AD7829-1 can be said to dissipate 36 mW (maximum) for 1.33 μs during each conversion cycle. If the throughput rate is 100 kSPS, the cycle time is 10 μs and the average power dissipated during each cycle is (1.33/10) × ...
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... CONVST pulse approximately 100 ns after the end of a conversion, that is, upon the rising edge of the Mode 1 Operation (High-Speed Sampling) When the AD7829-1 is operated in Mode not powered down between conversions. This mode of operation allows high throughput rates to be achieved. Figure 21 shows how this ...
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... AD7829-1 t POWER-UP CONVST EOC CS RD DB0 TO DB7 POWER DOWN HERE t 1 VALID DATA Figure 22. Mode 2 Operation Rev Page ...
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... AD7829-1 parallel interface. The multiplexer address is latched into the AD7829-1 on the falling edge of the RD input. The on- chip track/hold goes into hold mode on the falling edge of CONVST . A conversion is also initiated at this point. When the ...
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... Port 2. Port 2 latches remain stable when the AD7829-1 is addressed, because they do not have to be turned around (set to 1) for data input the case for Port 0. 1 ...
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... AD7829 ADDRESS A15 DECODE RD DB7 TO DB0 Figure 27. AD7829-1 Simplified Microinterfacing Scheme MICROPROCESSOR READ CYCLE A15 DB0 TO DB7 MUX ADDRESS (CHANNEL SELECTION A0 TO A2) LATCHED Rev Page AD7829-1 ADC I/O ADDRESS MUX ADDRESS A/D RESULT ...
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... AD7829-1 OUTLINE DIMENSIONS 28 0.30 (0.0118) 0.10 (0.0039) COPLANARITY 0.10 PIN 1 0.15 0.05 COPLANARITY ORDERING GUIDE Model Temperature Range AD7829BRU-1 −40°C to +85°C AD7829BRU-1REEL7 −40°C to +85°C 1 AD7829BRUZ-1 −40°C to +85°C 1 AD7829BRUZ-1REEL7 −40°C to +85°C AD7829BRW-1 −40°C to +85°C AD7829BRW-1RL7 −40°C to +85°C ...