CDB5378 Cirrus Logic Inc, CDB5378 Datasheet
CDB5378
Specifications of CDB5378
Related parts for CDB5378
CDB5378 Summary of contents
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Low-power, High-performance Modulator Features Fourth-order ΔΣ Architecture • Clock-jitter-tolerant architecture • Input signal bandwidth kHz • Max AC amplitude • Max DC amplitude: ± 2.5 V High Dynamic Range • 127 dB ...
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TABLE OF CONTENTS 1. CHARACTERISTICS AND SPECIFICATIONS ........................................................................ 4 SPECIFIED OPERATING CONDITIONS ................................................................................. 4 TEMPERATURE CONDITIONS ............................................................................................... 5 ABSOLUTE MAXIMUM RATINGS ........................................................................................... 5 ANALOG INPUT CHARACTERISTICS ................................................................................... 6 ANALOG OUTPUT CHARACTERISTICS ............................................................................... 7 MODULATOR CHARACTERISTICS ........................................................................................ 8 PERFORMANCE PLOTS ......................................................................................................... ...
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DAC CAP± Connection ................................................................................................... 30 7.6 Analog Differential Signals .............................................................................................. 30 8. VOLTAGE REFERENCE ........................................................................................................ 31 8.1 VREF Power Supply ........................................................................................................ 31 8.2 VREF RC Filter ................................................................................................................ 31 8.3 VREF PCB Routing ......................................................................................................... 31 8.4 VREF Input Impedance ................................................................................................... ...
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CHARACTERISTICS AND SPECIFICATIONS • Min / Max characteristics and specifications are guaranteed over the • Typical performance characteristics and specifications are measured at nominal supply voltages and T • GND = 0 V. Single-ended voltages with respect to GND, ...
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TEMPERATURE CONDITIONS Parameter Ambient Operating Temperature Storage Temperature Range Allowable Junction Temperature Junction to Ambient Thermal Impedance (4-layer PCB) ABSOLUTE MAXIMUM RATINGS Parameter DC Power Supplies Analog Supply Differential Digital Supply Differential Input Current, Power Supplies Input Current, Any Pin ...
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ANALOG INPUT CHARACTERISTICS Parameter VREF Input {VREF+} - {VREF-} VREF- VREF Input Current, Modulator Only VREF Input Current, Modulator + DAC AC Mode VREF Input Current, Modulator + DAC DC Mode VREF Input Noise , Modulator INR± INF± Inputs External ...
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ANALOG OUTPUT CHARACTERISTICS Parameter DAC Analog OUT± Output ± Analog External Load at OUT (Note 10, 11) Differential Output Impedance Single-ended Output Impedance High-Z Impedance ± Crosstalk to BUF High-Z Output DAC Analog BUF± Output ± Analog External Load at ...
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MODULATOR CHARACTERISTICS Parameter Input Characteristics Input Signal Frequencies Full Scale Differential AC Input Full Scale Differential DC Input Input Voltage Range (Signal + V cm Input Common Mode Voltage Dynamic Performance Dynamic Range (Note 16) Signal Dependent Noise (Note 17, ...
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PERFORMANCE PLOTS Figure 2. Modulator + Test DAC Dynamic Performance DS703F2 Figure 1. Modulator Noise Performance CS5373A 9 ...
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DAC AC DIFFERENTIAL MODES Parameter AC Differential Characteristics Full-scale Differential AC Output Full-scale Bandwidth Impulse Amplitude AC Differential Accuracy Full-scale Accuracy Relative Accuracy Full-scale Drift DC Common Mode Characteristics Common Mode Common Mode Drift Notes: 22. Maximum ...
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DAC AC DIFFERENTIAL MODES (CONT.) Parameter Signal to Noise ± Signal to Noise (OUT Unloaded) (Note 25) ± Signal to Noise (BUF Unloaded) (Note 25, 26) ± Signal to Noise (BUF 1 kΩ load) (Note 25, 26) ...
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DAC DC COMMON MODE 4 Parameter DC Common Mode Characteristics Common Mode Output Common Mode Drift DC Common Mode Accuracy ± Common Mode Match (OUT ) ± Common Mode Match (BUF ) Noise ± Noise (OUT Unloaded) (Note 25) ± ...
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DAC DC DIFFERENTIAL MODE 5 Parameter DC Differential Mode Characteristics Full-scale Differential DC Output (Note 28) DC Differential Accuracy ± Full-scale Accuracy (OUT ) ± Full-scale Accuracy (BUF ) Relative Accuracy Full-scale Drift DC Common Mode Characteristics Common Mode Common ...
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DAC AC COMMON MODE 6 Parameter AC Common Mode Characteristics Full-scale Common Mode AC Output (Note 29) Full-scale Bandwidth Impulse Amplitude AC Common Mode Accuracy ± Common Mode Match (OUT Unloaded) (Note 18, 27, 29) ± Common Mode Match (BUF ...
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DIGITAL CHARACTERISTICS Parameter Digital Inputs High-level Input Voltage Low-level Input Voltage Input Leakage Current Digital Input Capacitance Input Rise Times Except MCLK Input Fall Times Except MCLK Digital Outputs = -40 μA High-level Output Voltage, I out = 40 μA ...
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DIGITAL CHARACTERISTICS (CONT.) Parameter Master Clock Input MCLK Frequency MCLK Period MCLK Duty Cycle MCLK Rise Time MCLK Fall Time MCLK Jitter (In-band or aliased in-band) MCLK Jitter (Out-of-band) Master Sync Input MSYNC Setup Time to MCLK Rising MSYNC Period ...
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DIGITAL CHARACTERISTICS (CONT.) SYNC MCLK (2.048 MHz) MSYNC t 0 MDATA (512 kHz) MFLAG TDATA (256 kHz) MCLK (2.048 MHz) t mss MSYNC MDATA (2.048 MHz) MFLAG TDATA (256 kHz) DS703F2 Figure 4. System Timing Diagram t t msh mclk ...
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POWER SUPPLY CHARACTERISTICS Parameter Modulator Power Supply Current Analog Power Supply Current Digital Power Supply Current DAC AC Mode Supply Current Analog Power Supply Current Digital Power Supply Current DAC DC Mode Supply Current Analog Power Supply Current Digital Power ...
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GENERAL DESCRIPTION The CS5373A is a high-performance, fourth- order ΔΣ modulator integrated with a digital-to- analog converter (DAC). When combined with a CS3301A/02A differential amplifier and the CS5378 digital filter, a small low-power self- testing high-accuracy single-channel mea- surement ...
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SYSTEM DIAGRAM Geophone or M Hydrophone U Sensor X SENSOR TEST OUTPUT VA+ ELECTRONICS TEST OUTPUT 10 Ω 2.5 V VREF 100 µF VA- 680 Ω INPUT FROM 680 Ω CS 3301 A/02 A 680 Ω AMPLIFIER 680 Ω ...
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MODULATOR MODE 4. POWER MODES The CS5373A has five power modes. Modula- tor mode, AC test modes, and DC test modes are operational modes, while power down and sleep mode are non-operational standby modes. 4.1 Power Down If MCLK is ...
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OPERATIONAL MODES The CS5373A has seven operational modes and one sleep mode selected by the MODE2, MODE1, and MODE0 pins. Modes of Operation MODE Selection [2:0] Mode Description Modulator: enabled. DAC: sleep ...
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Modulator Idle Tones The CS5373A modulator is ΔΣ type and so can produce ‘idle tones’ in the measurement band- width when the differential input signal is a steady-state DC signal within ± mid- scale. Idle tones ...
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Differential AC test signals out of the CS5373A consist of two halves with equal but opposite magnitude, varying about a common mode voltage. A full-scale 5 V differential AC sig- PP nal centered on a -0.15 V common mode volt- ...
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In mode 4, both sets of analog outputs (OUT and BUF) are enabled. 5.3.2 DC Differential The second DC test mode (MODE 5) enables the modulator and DC test circuitry to create a precision differential ...
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VA+ 2.5 V VREF VA- INPUT FROM CS 3301 A/ PLIFIER 6. DIGITAL SIGNALS The CS5373A is designed to operate with the CS5378 digital filter. The digital filter gener- ates the master clock and synchronization sig- nals (MCLK ...
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MDATA Connection The CS5373A modulator outputs a ΔΣ serial bit stream to the MDATA pin, with a one’s den- sity proportional to the differential amplitude of the analog input signal. The output bit rate from the MDATA output is ...
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VA+ 2.5 V VREF VA- INPUT FROM CS 3301 A/ PLIFIER 7. ANALOG SIGNALS The CS5373A has multiple differential analog inputs and outputs. The modulator analog in- puts are separated into rough and fine charge differential pairs (INR±, ...
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The -3 dB corner of the input anti-alias filter is nominally set to the internal analog sampling rate divided by 64, which itself is a division the MCLK input rate. • MCLK Frequency = 2.048 MHz • ...
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One external input is typically dedicated to sensor measurements and the other to testing the electronics channel. The OUT± outputs are enabled in all opera- tional modes except modulator (MODE 0), “AC BUF Only” ...
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From VA+ Regulator 100 μF From VA- Regulator 100 μF 8. VOLTAGE REFERENCE The CS5373A requires a 2.500 V precision voltage reference to be supplied to the VREF pins. 8.1 VREF Power Supply To guarantee proper regulation headroom for the ...
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MCLK. The voltage reference external RC filter series resistor creates a voltage divider with the VREF input impedance to reduce the effective applied input voltage. To minimize gain error resulting from this voltage divider effect, the RC filter series ...
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To VA+ Regulator To VA- Regulator 100 uF 9. POWER SUPPLIES The CS5373A has a positive analog power supply pin (VA+), a negative analog power supply pin (VA-), a digital power supply pin (VD), and a ground pin (GND). For ...
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SCR Latch-up The VA- pin is tied to the CS5373A CMOS substrate and must always be the most-nega- tive voltage applied to the device to ensure SCR latch-up does not occur. In general, latch-up may occur when any pin ...
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Full-scale Accuracy - Variation in the measured output voltage from the theoretical full-scale output voltage at 1x attenuation. The following formula is used to calculate full-scale accuracy full scale accuracy = • Relative Accuracy - Variation in ...
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PIN DESCRIPTION Positive Capacitor Output Negative Capacitor Output Positive Buffered Output Negative Buffered Output Positive High Precision Output Negative High Precision Output Positive Analog Power Supply Negative Analog Power Supply Negative Voltage Reference Positive Voltage Reference Positive Analog Rough ...
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Pin Pin # I/O Name ATT2, 22, I Attenuation Range. Selects the output attenuation range. 23, ATT1, 24 ATT0 Selection MODE2, 25, I Mode Selection. Determines the operational mode of the device. ...
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PACKAGE DIMENSIONS 28L SSOP PACKAGE DRAWING TOP VIEW INCHES DIM MIN 0.002 A2 0.064 b 0.009 D 0.390 E 0.291 E1 0.197 e 0.022 L 0.025 ∝ 0° Notes: 1. “D” ...
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INFORMATION Model CS5373A-ISZ (lead free) 14.ENVIRONMENTAL, MANUFACTURING, & HANDLING INFORMATION Model Number CS5373A-ISZ (lead free) * MSL (Moisture Sensitivity Level) as specified by IPC/JEDEC J-STD-020. 15.REVISION HISTORY Revision Date PP1 NOV 2005 Preliminary release for CS5373A. PP2 NOV 2005 ...
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Contacting Cirrus Logic Support For all product questions and inquiries contact a Cirrus Logic Sales Representative. To find the one nearest to you go to IMPORTANT NOTICE Cirrus Logic, Inc. and its subsidiaries ("Cirrus") believe that the information contained in ...