LTC1404 LINER [Linear Technology], LTC1404 Datasheet
LTC1404
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LTC1404 Summary of contents
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... This easy-to-use device comes complete with a 160ns sample-and-hold and a precision reference. Unipolar and bipolar conversion modes add to the flexibility of the ADC. The LTC1404 has two power saving modes: Nap and Sleep. In Nap mode, it consumes only 7.5mW of power and can wake up and convert immediately. In the Sleep mode, it consumes power typically ...
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... Unipolar Operation .................. – 0. Bipolar Operation........... (V – 0.3V Power Dissipation.............................................. 300mW Operating Ambient Temperature Range LTC1404C................................................ LTC1404I............................................ – Junction Temperature.......................................... 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 POWER REQUIRE E TS SYMBOL ...
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... 4.75V 4.75V – 4.75V – 200 4.75V 160 4.75V 1.6mA CC O LTC1404 MIN TYP MAX UNITS 12 Bits 1 LSB 1 LSB 6 LSB 8 LSB 15 LSB 10 45 ppm/ C MIN TYP MAX UNITS – ...
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... LTC1404 U U DIGITAL I PUTS AND OUTPUTS SYMBOL PARAMETER I Hi-Z Output Leakage D OZ OUT C Hi-Z Output Capacitance D OZ OUT I Output Source Current SOURCE I Output Sink Current SINK CHARACTERISTICS SYMBOL PARAMETER f Maximum Sampling Frequency SAMPLE(MAX) t Conversion Time CONV t Acquisition Time (Unipolar Mode) ACQ ...
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... Signal-to-Noise Ratio (Without Harmonics) vs Input Frequency 600kHz SAMPLE 0 10 100 INPUT FREQUENCY (kHz) LTC1404 Bipolar Mode Differential Nonlinearity vs Output Code 1. 600kHz SAMPLE 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 –2048 –1024 0 3584 4096 –1536 –512 512 ...
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... LTC1404 W U TYPICAL PERFORMANCE CHARACTERISTICS Unipolar Mode Distortion vs Input Frequency 600kHz SAMPLE –10 –20 –30 –40 –50 –60 2ND HARMONIC –70 THD –80 –90 3RD HARMONIC –100 10 100 INPUT FREQUENCY (kHz) Unipolar Mode Intermodulation Distortion Plot at 300kHz 600kHz SAMPLE – ...
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... Reference Voltage vs Load Current 2.45 2.44 2.43 2.42 2.41 2.40 2.39 –8 –7 –6 –5 –4 –3 –2 – LOAD CURRENT (mA) 1404 G21 LTC1404 Unipolar Mode Peak Harmonic or Spurious Noise vs Input Frequency 600kHz SAMPLE –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 10 100 1000 ...
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... LTC1404 W U TYPICAL PERFORMANCE CHARACTERISTICS Unipolar Mode Temperature 600kHz SAMPLE 0 –50 – TEMPERATURE ( PIN FUNCTIONS V (Pin 1): Positive Supply, 5V. Bypass to GND ( tantalum in parallel with 0.1 F ceramic). A (Pin 2): Analog Input 4.096V (Unipolar), 2.048V IN (Bipolar). V (Pin 3): 2.43V Reference Output. Bypass to GND REF (10 F tantalum in parallel with 0 ...
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... TEST CIRCUITS D OUT 3k Hi SAMPLE 2.43V REF 12-BIT CAPACITIVE DAC 12 SUCCESSIVE APPROXIMATION REGISTER/PARALLEL TO SERIAL CONVERTER D OUT C LOAD Hi-Z LTC1404 ZEROING SWITCH V CC GND V SS COMP D OUT 1404 LOAD Hi Hi-Z OL 1404 TC01 9 ...
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... W U Dynamic Performance The LTC1404 has excellent high speed sampling capabil- ity. FFT (Fast Fourier Transform) test techniques are used to test the ADC’s frequency response, distortion and noise at the rated throughput. By applying a low distortion sine wave and analyzing the digital output using an FFT algo- rithm, the ADC’ ...
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... S/( the equation – where N is the effective number of bits of resolution and S/( expressed in dB. At the maximum sampling rate of 600kHz, the LTC1404 maintains very good ENOBs up to the Nyquist input frequency of 300kHz (refer to Figure 3 NYQUIST 10 FREQUENCY 9 8 ...
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... S/( becomes dominated by distortion at frequencies far be- yond Nyquist. Driving the Analog Input The analog input of the LTC1404 is easy to drive. It draws only one small current spike while charging the sample and-hold capacitor at the end of a conversion. During conversion, the analog input draws only a small leakage current ...
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... For zero full-scale error, apply an GND V analog input of 4.0945V (FS – 1.5LSB or last code transi- SS 1404 F06 tion) at the input and adjust R5 until the LTC1404 output –5V code flickers between 1111 1111 1110 and 1111 1111 1111. LTC1404 5V ...
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... ANALOG INPUT 2.048V 1 FS/2 – 1LSB 1404 F09 Figure 10c. LTC1404 Bipolar Offset and Full-Scale Adjust Circuit Bipolar Offset and Full-Scale Error Adjustments A IN Bipolar offset and full-scale errors are adjusted in a similar fashion to the unipolar case. Bipolar offset error adjust- ment is achieved by applying an input voltage of – 0.5mV LTC1404 (– ...
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... Figure 11 shows the recommended system ground con- nections. All analog circuitry grounds should be termi- nated at the LTC1404 GND pin. The ground return from the LTC1404 Pin 4 to the power supply should be low imped- ance for noise free operation. Digital circuitry grounds must be connected to the digital supply common ...
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... The digital interface requires only three digital lines. CLK and CONV are both inputs, and the D the conversion result in serial form. Figure 13 shows the digital timing diagram of the LTC1404 during the A/D conversion. The CONV rising edge starts voltage ramp-up time the conversion. Once initiated, it can not be restarted until the conversion is completed ...
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... HOLD D10 REFRDY BIT + 12-BIT DATA WORD t CONV t SAMPLE Figure 13. ADC Digital Timing Diagram CLK OUT V OL Figure 14. CLK to D Delay OUT LTC1404 ACQ SAMPLE ...
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... F Logic Analyzer Waveforms Show 2.05 s Throughput Rate (Input Voltage = 1.606V, Output Code = 0110 0100 0110 = 1606 NOTE: THE TMS320C50-40MHz HAS A LIMITED SERIAL PORT CLOCK SPEED OF 7.8MHz. TO ALLOW THE LTC1404 TO RUN AT ITS MAXIMUM SPEED OF 9.6MHz, THE TMS320C50-57 OR TMS320C50-80MHz IS NEEDED Data from the LTC1404 Loaded into the TMS320C50’s TRCV Register X Data Stored in the TMS320C50’ ...
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... AND #1FFFh, 0 SACL *+, 0 LACC AR7 SUB #0F05h,0 BCND END_TRCV, GEQ ; If the end sample address has exceeded jump SPLK #040h, IMR RETE *After Obtained the Data from LTC1404, Program Jump to END_TRCV* END_TRCV: SPLK #002h, IMR CLRC INTM SUCCESS: B SUCCESS *Fill the Unused Interrupt with RETE, to avoid program get “lost”* ...
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... LTC1404 U TYPICAL APPLICATIONS LTC1404 Interface to the ADSP2181’s SPORT0 (Frame Sync is Generated from RFS0 Logic Analyzer Waveforms Show 1.67 s Throughput Rate (Input Voltage = 1.604V, Output Code = 0110 0100 0100 = 1604 NOTE: WITHOUT THE EXTERNAL CLOCKING SIGNAL, THE ADSP2181 SCLK0 CAN BE PROGRAMMED TO RUN AT 8.3MHz ...
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... U TYPICAL APPLICATIONS THIS PROGRAM DEMONSTRATES THE LTC1404 INTERFACE TO THE ADSP-2181. FRAME SYNC PULSE IS GENERATED FROM RFS. DATA SHIFT CLOCK IS EXTERNALLY GENERATED. /*Section 1: Initialization*/ .module/ram/abs = 0 adspltc; /*define the program module*/ jump start; /*jump over interrupt vectors*/ nop; nop; nop; rti; rti; rti; rti; ...
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... TYPICAL APPLICATIONS Quick Look Circuit for Converting Data to Parallel Format 0.1 F ANALOG INPUT 2 (0V TO 4.096V) 2.43V 3 REFERENCE + OUTPUT 0 CONV LTC1404 7 CONV CLK V REF 5 GND D OUT 3-WIRE SERIAL INTERFACE LINK CLK 5V 10 SRCLR 12 15 RCK ...
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... DWG # 05-08-1610) 8 0.228 – 0.244 (5.791 – 6.197 0.053 – 0.069 (1.346 – 1.752) 0 – 8 TYP 0.014 – 0.019 (0.355 – 0.483) LTC1404 0.189 – 0.197* (4.801 – 5.004 0.150 – 0.157** (3.810 – 3.988 0.004 – 0.010 (0.101 – ...
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... LTC1404 U TYPICAL APPLICATIONS LTC1404 Interface to TMS320C50 Running at 5MHz without External Clock + 10 F LTC1404 Interface to ADSP2181 Running at 8.3MHz without External Clock + 10 F RELATED PARTS 12-Bit Parallel Output ADCs PART NUMBER DESCRIPTION LTC1273/LTC1275/ Complete 5V Sampling 12-Bit ADCs with 70dB LTC1276 SINAD at Nyquist LTC1274/LTC1277 ...