LTC2435CGN Linear Technology, LTC2435CGN Datasheet
LTC2435CGN
Specifications of LTC2435CGN
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LTC2435CGN Summary of contents
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... The LTC2435/LTC2435-1 communicate through a flexible 3-wire digital interface which is compatible with SPI and TM MICROWIRE , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. No Latency ΔΣ trademark of Linear Technology Corporation. Protected by U.S. Patents including 6140950, 6169506 INTERNAL OSC/50Hz REJECTION (LTC2435) ...
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... W ORDER I FOR ATIO LEAD FREE FINISH TAPE AND REEL LT2435CGN#PBF LTC2435CGN#TRPBF LT2435IGN#PBF LTC2435CGN#TRPBF LT2435-1CGN#PBF LTC2435-1CGN#TRPBF LT2435-1IGN#PBF LTC2435-1IGN#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on nonstandard lead based finish parts. For more information on lead free part marking, go to: ...
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U CO VERTER CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS 2.5V ≤ REF Input Common Mode Rejection DC GND ≤ IN 2.5V ≤ REF Input Common Mode Rejection 60Hz ±2% (LTC2435) GND ≤ IN 2.5V ≤ REF ...
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LTC2435/LTC2435 DIGITAL I PUTS A D DIGITAL OUTPUTS operating temperature range, otherwise specifications are at T SYMBOL PARAMETER V High Level Input Voltage IH CS Low Level Input Voltage IL CS High ...
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CHARACTERISTICS range, otherwise specifications are at T SYMBOL PARAMETER f External Oscillator Frequency Range EOSC t External Oscillator High Period HEO t External Oscillator Low Period LEO t Conversion Time (LTC2435) CONV Conversion Time (LTC2435-1) ...
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LTC2435/LTC2435 TYPICAL PERFOR A CE CHARACTERISTICS Total Unadjusted Error ( 5V) REF –340 F = GND REF T = –45° 2.5V ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS RMS Noise vs Input Differential Voltage 1 1 REF V = 2.5V INCM 1 GND 25°C 1.2 A 1.1 1.0 0.9 ...
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LTC2435/LTC2435 TYPICAL PERFOR A CE CHARACTERISTICS Full-Scale Error vs Temperature –330 F = GND REF –340 V = 2.5V INCM +FS ERROR –350 –FS ERROR –360 –370 –60 –40 –20 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Conversion Current vs Temperature 240 V = 5.5V CC 230 220 CC 210 F = GND GND 200 SCK = NC SDO = NC 190 V = ...
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LTC2435/LTC2435 CTIO S GND (Pins 10, 15, 16): Ground. Multiple ground pins internally connected for optimum ground current flow and V decoupling. Connect each one of these pins ...
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CTIO AL BLOCK DIAGRA V CC GND + + IN ∫ ∫ – – REF – REF – + DAC TEST CIRCUITS SDO 1.69k C LOAD Hi ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO CONVERTER OPERATION Converter Operation Cycle The LTC2435/LTC2435-1 are low power, delta-sigma ana- log-to-digital converters with an easy to use 3-wire serial interface (see Figure 1). Their operation is made up of three ...
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U U APPLICATIO S I FOR ATIO The LTC2435/LTC2435-1 perform a full-scale calibration every conversion cycle. This calibration is transparent to the user and has no effect on the cyclic operation de- scribed above. The advantage of continuous calibration is ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO Output Data Format The LTC2435/LTC2435-1 serial output data stream is 24 bits long. The first 3 bits represent status information indicating the sign and conversion state. The next 21 bits are the ...
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U U APPLICATIO S I FOR ATIO tional to V (see Figure 4), several characteristics of this CC variation can be used to eliminate the effects. First, the variation with respect to supply voltage is linear. Second, the magnitude of ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO The LTC2435 internal oscillator provides better than 110dB normal mode rejection at the line frequency and its harmon- ics for 50Hz ±2% or 60Hz ±2%. For 60Hz rejection, F should be connected ...
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U U APPLICATIO S I FOR ATIO –60 –70 –80 –90 –100 –110 –120 –130 –140 –12 –8 – INPUT FREQUENCY DEVIATION FROM NOTCH FREQUENCY (%) 2435 F07a Figure 7a. LTC2435/LTC2435-1 Normal Mode Rejection When Using an ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO Serial Clock Input/Output (SCK) The serial clock signal present on SCK (Pin 13) is used to synchronize the data transfer. Each bit of data is shifted out the SDO pin on the ...
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U U APPLICATIO S I FOR ATIO External Serial Clock, Single Cycle Operation (SPI/MICROWIRE Compatible) This timing mode uses an external serial clock to shift out the conversion result and a CS signal to monitor and control the state of ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO CS TEST EOC BIT 0 SDO EOC Hi-Z Hi-Z SCK (EXTERNAL) SLEEP CONVERSION DATA OUTPUT SLEEP TEST EOC Figure 9. External Serial Clock, Reduced Data Output Length The external serial clock mode ...
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U U APPLICATIO S I FOR ATIO When testing EOC, if the conversion is complete (EOC = 0), the device will exit the sleep state and enter the data output state. In order to allow the device to return to ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO HIGH driven by an external oscillator of frequency then t is 3.6 pulled HIGH before EOSC EOCtest EOSC time t , the ...
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U U APPLICATIO S I FOR ATIO A similar situation may occur during the sleep state when CS is pulsed HIGH-LOW-HIGH in order to test the conver- sion status. If the device is in the sleep state (EOC = 0), ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO PRESERVING THE CONVERTER ACCURACY The LTC2435/LTC2435-1 are designed to reduce as much as possible conversion result sensitivity to device decoupling, PCB layout, antialiasing circuits, line fre- quency perturbations and so on. Nevertheless, ...
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U U APPLICATIO S I FOR ATIO Driving the Input and Reference The input and reference pins of the LTC2435/LTC2435-1 converters are directly connected to a network of sampling capacitors. Depending upon the relation between the differential input voltage and ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO REF R (TYP LEAK 20k V + REF I LEAK (TYP LEAK 20k LEAK ...
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U U APPLICATIO S I FOR ATIO + – tance driving When F is driven by an external O oscillator with a frequency f EOSC clock operation), the typical differential input resistance is 12 Ω and ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO gain errors will be insignificant (about 1% of their respec- tive values over the entire temperature and voltage range). Even for the most stringent applications, a one-time calibration operation may be sufficient. ...
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U U APPLICATIO S I FOR ATIO 100 REF – GND REF 3.75V 1μF, 10μF IN – 1.25V 70 IN ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO Output Data Rate When using its internal oscillator, the LTC2435 can pro- duce readings per second with a notch frequency of 60Hz (F = LOW) and 12.5 readings per ...
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U U APPLICATIO S I FOR ATIO –200 INCM REFCM –220 CC REF F = EXT OSC O –240 –260 –280 –300 –320 –340 T A –360 –380 –400 ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO Normal Mode Rejection and Antialiasing One of the advantages delta-sigma ADCs offer over con- ventional ADCs is on-chip digital filtering. Combined with a large oversampling ratio, the LTC2435/LTC2435-1 sig- nificantly simplifies antialiasing ...
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U U APPLICATIO S I FOR ATIO As a result of these remarkable normal mode specifica- tions, minimal (if any) antialias filtering is required in front of the LTC2435/LTC2435-1. If passive RC components are placed in front of the LTC2435/LTC2435-1, ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO 0 MEASURED DATA CALCULATED DATA –20 –40 –60 –80 –100 –120 150 175 200 100 125 INPUT FREQUENCY (Hz) Figure 38. Input Normal Mode Rejection vs Input Frequency ...
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U U APPLICATIO S I FOR ATIO Sample Driver for LTC2435/LTC2435-1 SPI Interface Figure 41 shows the use of an LTC2435/LTC2435-1 with a differential multiplexer. This is an inexpensive multi- plexer that will contribute some error due to leakage if ...
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LTC2435/LTC2435 APPLICATIO S I FOR ATIO // Basic data collection program for the LTC2435 using the // PIC16F73 microcontroller. Collects data as fast as possible // and sends it out the serial port at 57600 baud as six ...
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U U APPLICATIO S I FOR ATIO while(1) { output_low(CS_); // Enable LTC2435 while(input(SDO Wait for SDO to fall, indicating end of conversion.*/ } printf(“%2X”,spi_read(0)); // Read first byte, send 2 hex characters. printf(“%2X”,spi_read(0)); // Read second byte, ...
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... If the bridge is composed of four equal 350Ω resistors, the differential component associated with mismatch of R3 and R6 is nearly constant with either polarity of excitation and, as with offset, its contribution is canceled. C-Load is a trademark of Linear Technology Corporation. 4 filter at about 12Hz. The . RMS ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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 its circuits as described herein will not infringe on existing patent rights. ...
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... LTC2435 REF 0.1μ – – REF LT1219 GND + 0.1μF SHDN 30pF 30pF Noise P-P Noise, Pin Compatible with LTC2435 RMS Noise, 4ppm INL, RMS Noise RMS LT 0807 REV B • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2001 2435 F46 24351fb ...