LTC1608 LINER [Linear Technology], LTC1608 Datasheet
LTC1608
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LTC1608 Summary of contents
Page 1
... The ADC has P compatible,16-bit parallel output port. There is no pipeline delay in conversion results. A separate convert start input and a data ready signal (BUSY) ease connections to FlFOs, DSPs and microprocessors. , LTC and LT are registered trademarks of Linear Technology Corporation. Circuitry in the LTC1608 is covered under US Patent #5,764,175 ...
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... LTC1608CG 33 SHDN LTC1608ACG CONV OGND 27 BUSY C/W JA LTC1608A MAX MIN TYP MAX UNITS 16 16 Bits 4 0.5 2 LSB 0.7 LSB RMS 0.125 0.05 0.125 % FSR 0.5 ppm/ C 0.25 0.125 0.25 0.25 0.25 15 ppm/ C MIN TYP MAX UNITS 2.5 1 ...
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... DD OUT V = 4.75V 160 A DD OUT V = 4.75V 1.6mA DD OUT High OUT DD CS High (Note 11 OUT OUT DD LTC1608 MIN TYP MAX – 100 – – 350 MIN TYP MAX 2.475 2.500 2.515 15 0.01 0.01 7.5 4.375 denotes specifications that apply over the full ...
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... LTC1608 W U POWER REQUIRE E TS otherwise specifications are (Note 5) A SYMBOL PARAMETER V Positive Supply Voltage DD V Negative Supply Voltage SS I Positive Supply Current DD Nap Mode Sleep Mode I Negative Supply Current SS Nap Mode Sleep Mode P Power Dissipation D Nap Mode Sleep Mode ...
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... G02 Distortion vs Input Frequency 0 –10 –20 –30 –40 –50 –60 –70 –80 THD 3RD –90 2ND –100 –110 10k 1k 100k INPUT FREQUENCY (Hz) 1608 G05 LTC1608 S/( Input Frequency and Amplitude 100 V = 0dB –20dB –40dB ...
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... LTC1608 W U TYPICAL PERFOR A CE CHARACTERISTICS Intermodulation Distortion 500kHz SAMPLE f = 96.56kHz IN1 – 99.98kHz IN2 –40 –60 –80 –100 –120 –140 0 50 100 150 200 250 FREQUENCY (kHz) 1608 G07 CTIO (Pin 1): Positive Analog Input. The ADC converts the ...
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... U U APPLICATIO S I FOR ATIO CONVERSION DETAILS The LTC1608 uses a successive approximation algorithm and internal sample-and-hold circuit to convert an analog signal to a 16-bit parallel output. The ADC is complete with a sample-and-hold, a precision reference and an internal clock. The control logic provides easy interface to micro- processors and DSPs ...
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... This device can also talk to 3V digital systems: the digital input pins HOLD (SHDN, CS, CONVST and RD) of the LTC1608 recognize inputs. The LTC1608 has a dedicated output HOLD supply pin (OV digital output pins (D0 to D15, BUSY) and allows the part + to talk to either digital systems ...
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... After the conversion is complete, the processor can read the new result and initiate another conversion. DIFFERENTIAL ANALOG INPUTS Driving the Analog Inputs The differential analog inputs of the LTC1608 are easy to drive. The inputs may be driven differentially single- ended input (i.e., the A – ...
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... LTC1608 U U APPLICATIO S I FOR ATIO CONVST t 6 BUSY DATA (N – 1) DATA D15 TO D0 Figure 5. Mode 1a. CONVST Starts a Conversion. Data Outputs Always Enabled (CONVST = CONVST t 6 BUSY DATA (N – 1) DATA D15 TO D0 Figure 6. Mode 1b. CONVST Starts a Conversion. Data Outputs Always Enabled ...
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... During conversion, the analog inputs draw only a small leakage current. If the source impedance of the driving circuit is low, then the LTC1608 inputs can be driven directly. As source impedance in- creases so will acquisition time (see Figure 10). For minimum acquisition time with high source impedance, a buffer amplifier should be used ...
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... LTC1608 U U APPLICATIO S I FOR ATIO The best choice for an op amp to drive the LTC1608 will depend on the application. Generally applications fall into two categories: AC applications where dynamic specifi- cations are most critical and time domain applications where DC accuracy and settling time are most critical. ...
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... The input span of the ADC can then be adjusted to match the peak input signal, maximizing the signal-to-noise ratio. The filtering of the internal LTC1608 reference amplifier will limit the bandwidth and settling time of this circuit. A settling time of 20ms should be allowed for after a reference adjustment ...
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... BOARD LAYOUT AND GROUNDING Wire wrap boards are not recommended for high resolu- tion or high speed A/D converters. To obtain the best per- formance from the LTC1608, a printed circuit board with LTC1608 Figure 15a ...
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... DC PERFORMANCE The noise of an ADC can be evaluated in two ways: signal- to-noise raio (SNR) in frequency domain and histogram in time domain. The LTC1608 excels in both. Figure 19a demonstrates that the LTC1608 has an SNR of over 90dB + – and A leads ...
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... R15 10pF C16 10pF 100 R9 6 402 – U4B 7 R10 LT1469 – R16 C19 10k 1000pF Figure 17a. LTC1608 Suggested Evaluation Circuit Schematic –5V C28 TC7SH08FUTE85L 1 F GND 5V R4 10k R3 R5 JP3 ...
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... FFT algorithm, the ADC’s spectral content can be examined for frequencies outside the fundamental. Figures 19a and 19b show typical LTC1608 FFT plots. Signal-to-Noise Ratio The signal-to-noise plus distortion ratio [S/(N + D)] is the ...
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... FREQUENCY (kHz) Figure 19a. This FFT of the LTC1608’s Conversion of a Full-Scale 3kHz Sine Wave Shows Outstanding Response with a Very Low Noise Floor When Sampling at 500ksps 0 f SAMPLE f = 98.754kHz IN –20 SINAD = 86.7dB THD = –92.6dB – ...
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... The full-linear bandwidth is the input frequency at which the S/( has dropped to 84dB (13.66 effective bits). The LTC1608 has been designed to optimize input band- width, allowing the ADC to undersample input signals with frequencies above the converter’s Nyquist Frequency. The noise floor stays very low at high frequencies ...
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... LTC1608 U TYPICAL APPLICATIO Using the LTC1608 and Two LTC1391s as an 8-Channel Differential 16-Bit ADC System 5V + LTC1391 CH0 CH0 CH1 D – – CH2 CH3 D OUT 12 5 CH4 CH5 CH6 CLK CH7 CH7 ...