LTC1287 LINER [Linear Technology], LTC1287 Datasheet
LTC1287
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LTC1287 Summary of contents
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... The low voltage operating capability and the low power consumption of this device make it ideally suited for battery applications. Given the ease of use, small U package size and the minimum number of interconnects for I/O, the LTC1287 can be used for remote sensing applications. LTCMOS is a trademark of Linear Technology Corporation 22 F TANTALUM V ...
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... Analog and Reference Inputs .... –0. Digital Inputs........................................ –0.3V to 12V Digital Outputs .......................... –0. Power Dissipation............................................. 500mW Operating Temperature Range LTC1287BI, LTC1287CI ................... – LTC1287BC, LTC1287CC ....................... Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec.)................ 300 ...
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... Note 9: Increased leakage currents at elevated temperatures cause the droop, therefore it is recommended that f f 3kHz CLK LTC1287 LTC1287B/LTC1287C MIN TYP MAX 50 40 100 40 100 600 800 100 5.0 14 100 (Note 3) LTC1287B/LTC1287C MIN TYP MAX 2.1 0.45 2.5 –2.5 2.90 2.7 2.85 0.05 0.10 0.3 3 –3 – levels, as high level analog CC 30kHz and ...
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... CLK = 500kHz 0.4 0.3 0.2 0 –40 – 3.0 AMBIENT TEMPERATURE (°C) LTC1287 G5 D Delay Time vs Temperature OUT 350 300 MSB-FIRST DATA 250 200 LSB-FIRST DATA 150 100 50 0 100 –40 – AMBIENT TEMPERATURE (°C) LTC1287 G8 2.5 3.0 LTC1287 G3 100 60 80 LTC1287 100 LTC1287 G9 ...
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... CTIO S # PIN FUNCTION DESCRIPTION 1 CS Chip Select Input A logic low on this input enables the LTC1287 +IN, –IN Analog Inputs These inputs must be free of noise with respect to GND. 4 GND Analog Ground GND should be tied directly to an analog ground plane Reference Input The reference input defines the span of the A/D converter and must be kept free of noise with respect to GND ...
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... CLK OUTPUT 6 D SHIFT OUT REGISTER 12-BIT SAR CONTROL AND TIMING V REF LTC1287 BD Delay Time, t OUT 0.45V t dDO Rise and Fall Times, t OUT Voltage Waveforms for t dis 2.1V t dis NOTE 1: WAVEFORM 1 IS FOR AN OUTPUT WITH INTERNAL CONDITIONS SUCH THAT THE OUTPUT IS HIGH UNLESS DISABLED BY THE OUTPUT CONTROL. ...
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... This provides OUT easy interface to MSB- or LSB-first serial ports. Bringing CS high resets the LTC1287 for the next data exchange. Logic Levels The logic level standards for this supply range have not been well defined. What standards that do exist are not universally accepted ...
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... The LTC1287 can be driven with 5V logic even when 3.3V. This is due to a unique input protection device that is found on the LTC1287. Microprocessor Interfaces The LTC1287 can interface directly (without external hard- ware) to most popular microprocessor (MPU) synchro- nous serial formats MPU without a serial interface is used, then three of the MPU’ ...
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... Source Resistance The analog inputs of the LTC1287 look like a 100pF capacitor (C value for R R will be reduced. For example, with – ...
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... BIT TEST (–) INPUT MUST SETTLE DURING THIS TIME Figure 8a. Setup Time ( Met SUCS t SMPL HI-Z 1ST BIT TEST (–) INPUT MUST SETTLE DURING THIS TIME Figure 8b. Setup Time ( Met SUCS + < 4.0k and C1 < SOURCE B11 B10 B9 LTC1287 F8a B11 B10 B9 LTC1287 F8b ...
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... Placing an RC network at the output of the op amps will inprove the settling response and also reduce the broadband noise. Figure 10. Poor Op Amp Settling Can Cause A/D Errors LTC1287 B11 B10 1ST BIT TEST (–) INPUT MUST SETTLE DURING THIS TIME LTC1287 F8c HORIZONTAL: 20 s/DIV 11 ...
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... For 0.25LSB error (150 V) the maximum input sinusoid with a 2.5V peak amplitude that can be digitized is 0.4Hz. Reference Input The voltage on the reference input of the LTC1287 determines the voltage span of the A/D converter. The reference input has transient capacitive switching cur- rents due to the switched capacitor conversion tech- nique (see Figure 12) ...
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... Offset and Noise are factors that must be considered when operating at low V Offset with Reduced V The offset of the LTC1287 has a larger effect on the output code when the A/D is operated with a reduced reference voltage. The offset (which is typically a fixed voltage) becomes a larger fraction of an LSB as the size of the LSB is reduced ...
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... The +IN input can accept a resistor value of 1k but the –IN input cannot accept more than 200 when clocked at its maximum clock frequency of 500kHz. If the LTC1287 is clocked at the maximum clock frequency and 200 is not enough to current limit the input source then the clamp diodes are recommended (Figures 16 and 17) ...
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... LTC1287 –IN GND TO OSCILLOSCOPE Figure 20. Scope Trace of the LTC1287 “Quick Look” Circuit Showing A/D Output 1010101010 (AAA Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of circuits as described herein will not infringe on existing patent rights. ...
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... LTC1287 PACKAGE DESCRIPTIO 0.290 – 0.320 (7.366 – 8.128) 0.008 – 0.018 0° – 15° (0.203 – 0.460) 0.038 – 0.068 0.385 ± 0.025 (0.965 – 1.727) (9.779 ± 0.635) 0.014 – 0.026 (0.360 – 0.660) 0.300 – 0.320 (7.620 – 8.128) ...