LTC1290BISW Linear Technology, LTC1290BISW Datasheet
LTC1290BISW
Specifications of LTC1290BISW
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LTC1290BISW Summary of contents
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... This allows easy interface to shift registers and a variety of processors. , LTC and LT are registered trademarks of Linear Technology Corporation. LTCMOS is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5287525. 12-Bit 8-Channel Sampling Data Acquisition System ...
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... Storage Temperature Range ................ – 65°C to 150°C CC Lead Temperature (Soldering, 10 sec.)................ 300° ACLK SCLK OUT CS + REF – REF – V AGND ORDER PART NUMBER LTC1290BCSW LTC1290CCSW LTC1290DCSW LTC1290BISW LTC1290CISW LTC1290DISW TOP VIEW CH0 CH1 2 19 ACLK CH2 3 18 SCLK CH3 CH4 5 16 ...
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VERTER A D ULTIPLEXER CHARACTERISTICS which apply over the full operating temperature range, otherwise specifications are at T PARAMETER CONDITIONS Offset Error (Note 4) Linearity Error (INL) (Notes 4, 5) Gain Error (Note 4) Minimum Resolution ...
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LTC1290 AC CHARACTERISTICS otherwise specifications are 25°C. (Note 3) A SYMBOL PARAMETER f Shift Clock Frequency SCLK f A/D Clock Frequency ACLK t Delay Time from CS↓ Data Valid ACC OUT t Analog Input Sample ...
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U DIGITAL A D ELECTRICAL C DC apply over the full operating temperature range, otherwise specifications are at T SYMBOL PARAMETER V High Level Input Voltage IH V Low Level Input Voltage IL I High Level Input Current IH I ...
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LTC1290 W U TYPICAL PERFOR A Supply Current vs Supply Voltage 26 ACLK = 4MHz T = 25° SUPPLY VOLTAGE, V (V) CC 1290 • TPC01 Change in Linearity vs ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Filter Resistor vs Cycle Time 10k 1k 100 R FILTER + V IN ≥ 1µF C FILTER 10 – 1.0 10 100 1000 10000 CYCLE TIME, t (µs) CYC 1290 • TPC10 ...
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LTC1290 CTIO S D (Pin 17): Digital Data Input. The A/D configuration IN word is shifted into this input after CS is recognized. SCLK (Pin 18): Shift Clock. This clock synchronizes the serial data transfer. ...
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TEST CIRCUITS D ACLK CS D OUT WAVEFORM 1 (SEE NOTE 1) D OUT WAVEFORM 2 (SEE NOTE 2) NOTE 1: WAVEFORM 1 IS FOR AN OUTPUT WITH INTERNAL CONDITIONS SUCH THAT THE OUTPUT IS HIGH UNLESS DISABLED BY THE ...
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LTC1290 PPLICATI FOR ATIO The LTC1290 is a data acquisition component which contains the following functional blocks: 1. 12-bit successive approximation capacitive A/D converter 2. Analog multiplexer (MUX) 3. Sample-and-hold (S/H) 4. Synchronous, full ...
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PPLICATI S I FOR ATIO MUX Address The first four bits of the input word assign the MUX configuration for the requested conversion. For a given channel selection, the converter will measure the voltage between the ...
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LTC1290 PPLICATI S I FOR ATIO Unipolar/Bipolar (UNI) The fifth input bit (UNI) determines whether the conver- sion will be unipolar or bipolar. When UNI is a logical one, a unipolar conversion will be performed on ...
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PPLICATI S I FOR ATIO MSB-First/LSB-First Format (MSBF) The output data of the LTC1290 is programmed for MSB- first or LSB-first sequence using the MSBF bit. For MSB first output data the input word clocked to ...
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LTC1290 PPLICATI S I FOR ATIO 8-Bit Word Length CS SCLK 1 (SB) D OUT B11 B10 MSB-FIRST D OUT B0 B1 LSB-FIRST 12-Bit Word Length CS 1 SCLK (SB) D OUT B11 B10 MSB-FIRST D ...
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PPLICATI S I FOR ATIO SHIFT MUX ADDRESS SAMPLE ANALOG IN CS SCLK B11 B10 OUT SHIFT MUX ADDRESS SAMPLE ANALOG IN CS SCLK B11 ...
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LTC1290 PPLICATI S I FOR ATIO A Table 2. Microprocessors with Hardware Serial Interfaces Compatible with the LTC1290** PART NUMBER TYPE OF INTERFACE Motorola MC6805S2, S3 SPI MC68HC11 SPI MC68HC05 SPI RCA CDP68HC05 SPI Hitachi HD6305 SCI ...
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PPLICATI S I FOR ATIO Hardware and Software Interface to Motorola MC68HC05C4 Processor LTC1290 CS SCLK • ANALOG • INPUTS D IN • • D OUT D from LTC1290 Stored in MC68HC05C4 RAM OUT MSB* B11 ...
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LTC1290 PPLICATI FOR ATIO 8051 Code MNEMONIC COMMENTS MOV P1,#02H Bit 1 Port 1 Set as Input CLR P1.3 SCLK Goes Low SETB P1.4 CS Goes High CONT MOV A,#0EH D Word for LTC1290 ...
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PPLICATI S I FOR ATIO 22µF TANTALUM ANALOG GROUND PLANE Figure 6. Example Ground Plane for the LTC1290 Figure 6 shows an example of an ideal ground plane design for a ...
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LTC1290 PPLICATI S I FOR ATIO “+” INPUT R + SOURCE 4TH SCLK C1 “–” INPUT R – LAST SCLK SOURCE V – Figure 9. Analog Input Equivalent Circuit “+” Input ...
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PPLICATI S I FOR ATIO maximum clock rates (ACLK = 4MHz and SCLK = 2MHz). Figures 11 and 12 show examples of adequate and poor op amp settling. HORIZONTAL: 500ns/DIV Figure 11. Adequate Settling of Op ...
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LTC1290 PPLICATI S I FOR ATIO Differential Inputs With differential inputs or when the COM pin is not tied to ground, the A/D no longer converts just a single voltage but rather the difference between two ...
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PPLICATI FOR ATIO 6. Reduced Reference Operation The effective resolution of the LTC1290 can be increased by reducing the input span of the converter. The LTC1290 exhibits good linearity and gain over a wide ...
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LTC1290 PPLICATI FOR ATIO f = 1kHz SAMPLE SNR = 73.25dB –20 –40 –60 –80 –100 –120 –140 FREQUENCY (kHz) Figure 17a. LTC1290 FFT Plot f ...
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PPLICATI S I FOR ATIO 1k V CH0 LTC1290 – V DGND AGND Figure 20. Overvoltage Protection for MUX How the various power supplies to the LTC1290 are applied can also lead to ...
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LTC1290 O U TYPICAL A PPLICATI A “Quick Look” Circuit for the LTC1290 Users can get a quick look at the function and timing of the LTC1290 by using the following simple circuit. REF D are tied to V selecting ...
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... CH6 IN (–) CH7 2MHz CLOCK 1ST CONVERSION (–) CH6 V MC68HC05C4 IN SCLK (+) CH7 MOSI MISO 2ND CONVERSION CO 1290 TA04 0.1µF –5V SNEAK-A-BIT is a trademark of Linear Technology Corp. LTC1290 SNEAK-A-BIT 1ST CONVERSION 4096 STEPS SOFTWARE 2ND CONVERSION 4096 STEPS –5V –5V 27 8191 ...
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LTC1290 O U TYPICAL A PPLICATI SNEAK-A-BIT Code D from LTC1290 in MC68HC05C4 RAM OUT Sign LOCATION $77 B12 B11 B10 LSB LOCATION $ Filled with 0s D Words for LTC1290 IN ...
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O U TYPICAL A PPLICATI Power Shutdown For battery-powered applications it is desirable to keep power dissipation at a minimum. The LTC1290 can be powered down when not in use reducing the supply current from a nominal value of 5mA ...
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LTC1290 PACKAGE DESCRIPTIO CORNER LEADS 0.300 BSC OPTION 0.015 – 0.060 (4 PLCS) (0.762 BSC) (0.381 – 1.524) 0.023 – 0.045 (0.584 – 1.143) HALF LEAD OPTION 0.008 – 0.018 0.045 – 0.068 (0.203 – 0.457) (1.143 – 1.727) FULL ...
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... MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 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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... Micropower Serial ADC Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● COMMENTS 1- or 2-Channel, Autoshutdown 6 8-Channel with Shutdown Output 4- or 8-Channel, 3V Versions Available www.linear.com ● 1290fe LT/LT 0805 REV E • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 1991 ...