AD1555AP Analog Devices Inc, AD1555AP Datasheet
AD1555AP
Specifications of AD1555AP
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AD1555AP Summary of contents
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FEATURES AD1555 Fourth Order - Modulator Large Dynamic Range 116 dB Min, 120 dB Typical @ 1 ms 117 dB Typical @ 0.5 ms Low Input Noise rms @ 4 ms with Gain of 34,128 Low Distortion: ...
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... –55 MIN MAX 2.990 –0.3 2.0 –10 – SINK = –2 mA 2.4 SOURCE –2– AGND = DGND = 0 V; MCLK = 256 kHz AD1555AP Typ Max Min Typ Max 120 116 120 119.5 115.5 119.5 117.5 114 117.5 109.5 104.5 109 –120 – ...
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... AD1556 output word rate, the inverse of the sampling rate. See Tables I, Ia, Ib for other output 2. 5.25 V; CLKIN = 1.024 MHz Notes All Filters Except F =16 kHz O F =16 kHz SINK I = –2 mA SOURCE kHz Power-Down Mode –3– AD1555/AD1556 AD1555AP Max Min Typ Max 5.25 4.75 5 5.25 –4.75 –5.25 –5 –4.75 5.25 4. 9 ...
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... kHz (1/2 ms) O 1.59 µV rms kHz (1 ms) O 1.13 µV rms F = 500 250 Hz (4 ms) 797 nV rms O Table Ia. Minimum Dynamic Performances (AD1555AP Only) Input and Gain MODIN kHz (1 ms) 116 500 Hz (2 ms) 119 250 Hz (4 ms) 122 O * Not tested in production. Guaranteed by design. ...
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TIMING SPECIFICATIONS 1 CLKIN Frequency CLKIN Duty Cycle Error 1 MCLK Output Frequency SYNC Setup Time SYNC Hold Time CLKIN Rising to MCLK Output Falling on SYNC CLKIN Falling to MCLK Output Rising CLKIN Falling to MCLK Output Falling MCLK ...
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AD1555/AD1556 CLKIN t 1 SYNC t 3 MCLK ( MDATA TDATA t 10 RESET CLKIN SYNC DRDY ERROR Figure 4. AD1556 RESET, DRDY, and Overwrite Timings DATA VALID ...
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RSEL DRDY R DOUT SCLK R SCLK t 31 MSB DIN REV. B MSB MSB– ...
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... Ground Voltage Differences DGND, AGND1, AGND2, AGND3 . . . . . . . . . . . ± 0.3 V Digital Inputs . . . . . . . . . . . . . . . . . . . . –0 Internal Power Dissipation AD1555 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8 W AD1556 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8 W Model AD1555AP AD1555APRL AD1555BP AD1555BPRL AD1556AS AD1556ASRL EVAL-AD1555/AD1556EB AD1555/56-REF *Contact factory for extended temperature range. CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection ...
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REV. B PIN CONFIGURATION 28-Lead PLCC (P-28A PIN 1 AIN(+) 5 25 AIN(– TIN(+) AD1555 TIN(– TOP VIEW (Not to Scale CB0 10 20 ...
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AD1555/AD1556 Pin No. Mnemonic Description 1 AGND1 Analog Ground 2 PGAOUT Programmable Gain Amplifier Output. The output of the on-chip programmable gain amplifier is available at this pin. Refer to Table III for PGA gain settings selection ...
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AD1556 PIN FUNCTION DESCRIPTIONS (continued) Pin No. Mnemonic Description 14 DOUT Serial Data Output. DOUT is used to access the conversion results or the contents of the Status Register, depending on the logic state of the RSEL pin. At the ...
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AD1555/AD1556 TERMINOLOGY DYNAMIC RANGE Dynamic range is the ratio of the rms value of the full scale to the total rms noise measured with the inputs shorted together in the bandwidth from the Nyquist frequency F value ...
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FREQUENCY – Hz TPC 1. FFT (2048 Points) Full-Scale MODIN Input 0 –20 –40 –60 –80 –100 –120 –140 –160 –180 –200 ...
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AD1555/AD1556 –128 –120 –113 –105 CMRR – dB TPC 7. Common-Mode Rejection Distribution (272 Units) 120 G = 8.5 115 110 105 G = 128 G ...
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FREQUENCY – Hz TPC 13. AD1556 Pass Band Ripple, F 0.20 0.15 0.10 0.05 0.00 –0.05 –0.10 –0.15 –0.20 0 1000 2000 FREQUENCY – Hz TPC 14. AD1556 ...
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AD1555/AD1556 CIRCUIT DESCRIPTION The AD1555/AD1556 chipset is a complete sigma-delta 24-bit A/D converter with very high dynamic range intended for the measurement of low frequency signals few kHz such as those in seismic applications. The AD1555 contains ...
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AIN are specifi- cally designed to ease the design. The external voltage spike is generally clamped by devices T1 and T2 at about hundred volts (for instance, devices T1 and T2 can be ...
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AD1555/AD1556 When the V input is selected, S4(+) and S4(–) are closed, all REF the other switches are opened, and a reference voltage (2.25 V) equal to half of the full-scale range is sampled. In this combina- tion, the gain ...
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DIGITAL FILTERING The AD1556 is a digital finite impulse response (FIR) linear phase low pass filter and serves as the decimation filter for the AD1555. It takes the output bitstream of the AD1555, filters and decimates user-selectable ...
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AD1555/AD1556 RESET Operation The RESET pin initializes the AD1556 in a known state. RESET is active on the next CLKIN rising edge after the RESET input is brought high as shown in Figure 4. The reset value of each bit ...
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DRDYBUF = 0 DRDYBUF = THE MICROPROCESSOR DRDY AD1556 AD1556 V DGND L AD1556 Figure 11. DRDY Output Pin Configuration Analog Input and Digital Output Data Format When operating with a nominal MCLK frequency ...
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AD1555/AD1556 Bit Number Name DB23 (MSB) ERROR DB22 OVWR DB21 MFLG DB20 X DB19 ACC DB18 DRDY DB17 FLSTL DB16 DRNG DB15 X DB14 X DB13 X DB12 X DB11 PWRDN DB10 CSEL DB9 X DB8 BW2 DB7 BW1 DB6 ...
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REV. B OUTLINE DIMENSIONS Dimensions shown in inches and (mm) 28-Lead PLCC (P-28A) 0.180 (4.57) 0.165 (4.19) 0.048 (1.21) 0.056 (1.42) 0.042 (1.07) 0.042 (1.07 PIN 1 IDENTIFIER 0.050 TOP VIEW (1.27) ...
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