ad1555xp Analog Devices, Inc., ad1555xp Datasheet
ad1555xp
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ad1555xp Summary of contents
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... CONTROL REGISTER STATUS REGISTER CSEL INPUT DIGITAL TDATA MUX FILTER DATA REGISTER CLOCK DIVIDER AD1556 CLKIN SYNC BW0...BW2 RESET PWRDN GND V © Analog Devices, Inc., 2002 f = 24.4Hz IN SNR = 116.7dB THD = –120.6dB 350 400 450 500 INPUT SHIFT DIN REGISTER SCLK CS R/W ...
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AD1555/AD1556 AD1555–SPECIFICATIONS Parameter Notes PGA Gain Settings 1, 2.5, 8.5, 34, 128 AC ACCURACY 1 Dynamic Range PGA Gain of 1 PGA Gain of 2.5 PGA Gain of 8.5 PGA Gain of 34 PGA Gain of 128 2 Total Harmonic ...
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Parameter Notes POWER SUPPLIES Recommended Operating Conditions +V A – Quiescent Currents 10 I(+ I(– I Power Dissipation PGA in Standby Mode In Power-Down Mode Reference Input = 3 ...
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AD1555/AD1556 Input and Gain MODIN Input Range 1.6 V rms Dynamic Range kHz (1/16 ms kHz (1/8 ms kHz (1/4 ms ...
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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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AD1555/AD1556 1 ABSOLUTE MAXIMUM RATINGS Analog Inputs Pins 7, 8, 23, 24, 25 –V A AIN(+), AIN(–) DC Input Current . . . . . . . . . . . ± 100 ...
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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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