AD1556 Analog Devices, AD1556 Datasheet
AD1556
Specifications of AD1556
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AD1556 Summary of contents
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... CMOS transistors. The AD1555 and AD1556 are packaged, respectively, in 28-lead PLCC and 44-lead MQFP packages and are specified from –55°C to +85°C (AD1556 and AD1555 B Grade) and from 0°C to 85°C (AD1555 A Grade). FUNCTIONAL BLOCK DIAGRAM ...
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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 Distortion PGA Gain of 1 PGA Gain of 2.5 PGA Gain of 8.5 PGA Gain of 34 PGA Gain of 128 ...
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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 = – ...
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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 kHz (1/2 ms) 117 kHz (1 ms) 120 500 Hz (2 ms) 123 250 Hz (4 ms) 126 dB O Equivalent Input Noise ...
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... MCLK frequency. 1.6mA OUTPUT PIN C L 50pF I 500 A OH Figure 2. Load Circuit for Digital Interface Timing –5– AD1555/AD1556 = 5 V 5%, AD1556 unless otherwise noted MIN MAX Min Typ Max 0.975 1.024 1.075 ...
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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 VALID Figure 3. AD1555/AD1556 Interface Timing –6– ...
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... DOUT SCLK R SCLK t 31 MSB DIN REV. B MSB MSB– Figure 5. Serial Read Timing MSB–1 Figure 6. Serial Write Timing –7– AD1555/AD1556 HI-Z LSB+1 LSB LSB+1 LSB ...
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... AGND . . . . . . . . . . . . . . . . . . . . . . . – +0 DGND . . . . . . . . . . . . . . . . . . . . . . . . –0 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. ...
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... PGA1 3 PGA2 4 PGA3 5 AD1556 PGA4 6 TOP VIEW (Not to Scale) BW0 7 BW1 8 9 BW2 10 H CONNECT –9– AD1555/AD1556 REFIN REFCAP2 REFCAP1 AGND3 –V A – CLKIN 31 SYNC 30 TDATA 29 CSEL PWRDN ...
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... AD1555. When used with the AD1556, these pins are generally directly tied to the CB0–CB4 output pins of the AD1556. CB0–CB2 are generally used to set the PGA gain or cause it to enter in the PGA standby mode (refer to Table III). CB3 and CB4 select the mux input voltage applied to the PGA as described in Table III ...
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... CLKIN Clock Input. The clock input signal, nominally 1.024 MHz, provides the necessary clock for the AD1556. This clock frequency is divided by four to generate the MCLK signal for the AD1555. 35 MCLK Modulator Clock. Provides the modulator sampling clock frequency. The modulator always samples at one-fourth the CLKIN frequency ...
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... IMD is expressed in decibels. OFFSET The offset is the difference between the ideal midscale input volt- age (0 V) and the actual voltage producing the midscale output code (code 000000H) at the output of the AD1556. The offset specification is referred to the output. This offset is intentionally /2. The O set at a nominal value of – ...
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... TPC 5. Dynamic Range Distribution (272 Units) 150 f = 24.4Hz IN SNR = 68.2dB 140 THD = –120dB 130 120 110 100 90 3000 3500 4000 –55 TPC 6. Common-Mode Rejection vs. Temperature –13– AD1555/AD1556 2 8 128 –35 – 105 TEMPERATURE – C –121 –119 –117 –118 DYNAMIC RANGE – ...
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... TPC 11. AD1556 Pass Band Ripple, F 0.20 0.15 0.10 0.05 0.00 –0.05 –0.10 –0.15 –0.20 100 125 0 = 250 Hz (4 ms) TPC 12. AD1556 Pass Band Ripple –14– 50 100 150 200 250 FREQUENCY – 500 Hz (2 ms) O 100 200 300 400 500 FREQUENCY – kHz (1 ms) ...
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... FREQUENCY – Hz TPC 14. AD1556 Pass Band Ripple, F REV. B 0.20 0.15 0.10 0.05 0.00 –0.05 –0.10 –0.15 –0.20 1500 2000 kHz (1/4 ms) TPC 15. AD1556 Pass Band Ripple 3000 4000 = 8 kHz (1/8 ms) O –15– AD1555/AD1556 4000 6000 8000 2000 FREQUENCY – kHz (1/16 ms) O ...
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... F The AD1555 operates from a dual analog supply (± 5 V), while the digital part of the AD1555 operates from supply. The AD1556 operates from a single 3 supply. Each device exhibits low power dissipation and can be configured for standby mode. Figure 7 illustrates a typical operating circuit. ...
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... CB0 to CB4 according to the Table III. This table is only valid when MCLK is toggling; otherwise, the AD1555 is powered down. When used in combination with the AD1556, this control bus could either be loaded by hardware (H/S pin high) or via the serial interface of the AD1556 (H/S pin low). ...
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... TPC 3. This high frequency noise is attenuated by the AD1556 digital filter. However, when the output word rate (OWR) of the AD1556 is higher than 4 kHz (–3 dB frequency is higher than 1634 Hz), the efficiency of this filtering is limited and slightly reduces the dynamic range, as shown in the Table I ...
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... Architecture The functional block diagram of the filter portion of the AD1556 is given in Figure 10. The basic architecture is a two-stage filter. The second stage has a decimation ratio of 4 for all filters except ...
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... CB0 Configuring and Interfacing the AD1556 The AD1556 configuration can be loaded either by hardware (H/S pin high) or via the serial interface of the AD1556 (H/S pin low). To operate with the AD1556, the CLKIN clock must be kept running at the nominal frequency of 1.024 MHz. Table V gives the description of each bit of the configuration register and Table VI defines the selection of the filter bandwidth ...
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... However, care should still be taken with regard to grounding layout. The printed circuit board that houses the AD1555 and the AD1556 should be designed so the analog and digital sections are separated and confined to certain areas of the board. This facilitates the use of ground planes that can be easily separated. ...
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... PGA Gain Select PGA Gain Select PGA Gain Select Evaluating the AD1555/AD1556 Performance Performances of the AD1555/AD1556 can be evaluated with the evaluation board EVAL-AD1555/AD1556EB. The evaluation board package includes a fully assembled and tested evaluation board, documentation, and software for controlling the board from a PC via the PC printer port. – ...
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... MAX SQ 0.390 (9.90) 0.041 (1.03) 0.029 (0.73 SEATING PLANE TOP VIEW (PINS DOWN) 11 0.010 (0.25 MAX 0.009 (0.23) 0.005 (0.13) 0.018 (0.45) 0.031 (0.80) BSC 0.012 (0.30) 0.083 (2.10) 0.077 (1.95) –23– AD1555/AD1556 0.025 (0.63) 0.015 (0.38) 0.021 (0.53) 0.013 (0.33) 0.430 (10.92) 0.390 (9.91) 0.032 (0.81) 0.026 (0.66) 0.040 (1.01) 0.025 (0.64 0.315 (8.00) REF 23 ...
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