LTC1419 LINER [Linear Technology], LTC1419 Datasheet
LTC1419
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LTC1419 Summary of contents
Page 1
... Two digitally selectable power shutdown modes provide flexibility for low power systems. The LTC1419 has a full-scale input range of 2.5V. Out- standing AC performance includes 81.5dB S/( and 93dB THD with a 100kHz input; 80dB S/( and 86dB THD at the Nyquist input frequency of 400kHz. ...
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... SS Digital Input Voltage (Note 4) ......... (V Digital Output Voltage ........ (V – 0.3V Power Dissipation............................................. 500mW Operating Temperature Range LTC1419C............................................... LTC1419I........................................... – Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................. 300 VERTER C HARA TERISTICS C PARAMETER ...
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... High OUT DD CS High (Note OUT OUT DD (Note 5) CONDITIONS (Notes 10, 11) (Note 10) SHDN = 0V SHDN = 0V SHDN = 0V SHDN = 0V LTC1419 MIN TYP MAX UNITS 78 81.5 dB 80.0 dB – 93 – – – 95 – – MHz ...
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... LTC1419 W U POWER REQUIRE E TS SYMBOL PARAMETER P Power Dissipation DIS Nap Mode Sleep Mode CHARACTERISTICS SYMBOL PARAMETER f Maximum Sampling Frequency SAMPLE(MAX) t Conversion Time CONV t Acquisition Time ACQ t Acquisition + Conversion Time ACQ + CONV Setup Time CONVST Setup Time ...
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... –90 DGND –100 1k 10k 100k 1M 2M RIPPLE FREQUENCY (Hz) 1419 G08 LTC1419 Distortion vs Input Frequency 0 –10 –20 –30 –40 –50 –60 –70 –80 THD –90 2ND –100 3RD – 110 1k 10k 100k 1M 2M ...
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... LTC1419 CTIO (Pin 1): 2.5V Positive Analog Input. IN – A (Pin 2): 2.5V Negative Analog Input (Pin 3): 2.5V Reference Output. Bypass to AGND REF with 1 F. REFCOMP (Pin 4): 4.06V Reference Output. Bypass to AGND with 10 F tantalum in parallel with 0 ceramic. AGND (Pin 5): Analog Ground. ...
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... The SAR contents (a 14-bit data word) which represents HOLD the difference output latches. COMP DYNAMIC PERFORMANCE The LTC1419 has excellent high speed sampling capabil- ity. FFT (Fast Fourier Transform) test techniques are used D13 to test the ADC’s frequency response, distortion and noise OUTPUT • ...
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... ADC and is directly related to the S/( the equation: = 800kHz N = [S/( – 1.76]/6.02 where N is the effective number of bits of resolution and S/( expressed in dB. At the maximum sampling rate of 800kHz the LTC1419 maintains near ideal ENOBs up to the Nyquist input frequency of 400kHz (refer to Figure 3). 300 350 400 1419 F02a Figure 3 ...
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... The inputs draw only one small current spike while charging the sample-and-hold capacitors at the end of conversion. During conversion the analog inputs draw only a small leakage current. If the source impedance of the driving circuit is low, then the LTC1419 inputs can be driven directly. As source impedance in- 300 350 400 creases so will acquisition time (see Figure 6) ...
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... If slower op amps are used, more settling time can be provided by increasing the time between conversions. The best choice for an op amp to drive the LTC1419 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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... Metal film surface mount resistors are much less susceptible to both problems. Input Range The 2.5V input range of the LTC1419 is optimized for low noise and low distortion. Most op amps also perform well over this same range, allowing direct coupling to the analog inputs and eliminating the need for special transla- tion circuitry ...
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... IN Full-Scale and Offset Adjustment Figure 11a shows the ideal input/output characteristics for the LTC1419. The code transitions occur midway between successive integer LSB values (i.e., – 0.5LSB, – 1.5LSB, – 2.5LSB,... FS – 1.5LSB, FS – 0.5LSB). The output is two’s complement binary with 1LSB = FS – ...
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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 performance from the LTC1419, a printed circuit board with ground plane is required. Layout should ensure that digital and analog signal lines are separated as much as possible ...
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... LTC1419 U U APPLICATIONS INFORMATION ...
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... U U APPLICATIONS INFORMATION Figure 13b. Suggested Evaluation Circuit Board—Component Side Silkscreen Figure 13c. Suggested Evaluation Circuit Board—Component Side Layout W U LTC1419 15 ...
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... The guaranteed maximum acquisition time is 300ns. In addition, a throughput time of 1.25 s and a minimum sampling rate of 800ksps are guaranteed. Power Shutdown The LTC1419 provides two power shutdown modes, nap and sleep, to save power during inactive periods. The nap mode reduces the power by 95% and leaves only the digital logic and reference powered up ...
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... After the conversion is complete, the processor can read the new result and initiate another conversion. t CONV (SAMPLE DATA (N – 1) DATA N DB13 TO DB0 DB13 TO DB0 ) LTC1419 1419 F15 Figure 15 CONVST Set-Up Timing DATA ( DB13 TO DB0 1419 F16 17 ...
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... LTC1419 U U APPLICATIONS INFORMATION CONVST BUSY DATA (N – 1) DATA DB13 TO DB0 Figure 17. Mode 1b. CONVST Starts a Conversion. Data Outputs Always Enabled (CONVST = CONVST BUSY RD DATA Figure 18. Mode 2. CONVST Starts a Conversion. Data is Read (SAMPLE CONVST t 6 BUSY ...
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... Plastic SSOP (0.209) (LTC DWG # 05-08-1640 – 8 0.0256 (0.65) BSC 0.010 – 0.015 (0.25 – 0.38) LTC1419 DATA N DB13 TO DB0 1419 F20 0.397 – 0.407* (10.07 – 10.33 0.301 – 0.311 (7.65 – 7.90 0.068 – ...
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... LTC1419 PACKAGE DESCRIPTIO 0.291 – 0.299** (7.391 – 7.595) 0.010 – 0.029 45 (0.254 – 0.737) 0.009 – 0.013 NOTE 1 (0.229 – 0.330) 0.016 – 0.050 (0.406 – 1.270) NOTE: 1. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE MANUFACTURING OPTIONS. ...